rn rar aen Nature, | December 14, 1899. Nature A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE Se ‘oe Soy MaTionat WE * [ Nature, December 14, 1899 Nature, ] December 14, 1899 Nature A WEEKLY MIMSTRATED JOURNAL OF SCIENCE VOEUME LX MAY 1899 to OCTOBER 1899 “To the solid ground Of Nature trusts the mind which builds for aye.’—WoORDSWORTH ARSON oS” v4, Re LIBRE Vondon NeA CiVinlvie AGN A N Deo} simrreD NEW YORK: THE MACMILLAN COMPANY Nature, December 14 1899 RICHARD CLAY AND Sons, LIMITED, LONDON AND BUNGAY. Nature, December 14. 1899 PND EX ABAcuS, Calculation by, Maurice d’Ocagne, 363 Abbe (Prof. Cleveland), the Height of the Aurora, 130; Meteor- | ological Services in Russia, 299 ; Tornadoes, 328 Abbot (General H. J.), Climatology of Panama, 427 Abbott (A.), Progressive Lessons in Science, 543 Abelous (E.), Soluble Animal Ferment reductive of Nitrates, 264; Reducing Power of Extract of Animal Organs, 312 Abney (Captain W. de W., F.R.S.), Colour Sensations in Terms of Luminosity, 237 Aborigines of Australia, Cave Shelters and the, H. Ling Roth, 545 Abraham (H.), the Instantaneous Disappearance of the Kerr Phenomenon, 336 Abraham (M.), the Sterilising of Potable Water by Ozone, 24 Abt (A.), Magnetic Properties of Hematite, 540 Academies, the International Association of, 613 Acetylene, Velocity of Detonations of, Daniel Berthelot and H. Le Chatelier, 456 Achlya Americana, a Welsh Variety of, A. H. Trow, 37 Acids on Starch, the Action of, Dr. G. H. Morris, 608 Aclogue (A.), Faune de France, Mammifeéres, 410 Acoustics : Observations with Resonators for determining how Modulus of Decay is Affected, Dr. A. Pochettino, 17 ; Distant Sounds, W. F-. Sinclair, 125 ; the Boyle Lecture on the Per- ception of Musical Tone, Prof. McKendrick, 163 ; Transverse Tones of Caoutchouc Threads, V. von Lang, 384; Beats given by Vibrating Strings, C. Maltézos, 456 ; the Audibility of Sound in Air, Rev. J. M. Bacon, 484 Acqua (Dr. F. dell’), Meat Consumption in Italy, 352 Addenbrooke (Mr.), Quadrant Electrometer for Application to Alternating Current Measurements, 70 Adie (R. H.), an Introduction to the Carbon Compounds, 271 Aerolite,-the Bjurholm, 110 Aeronautics, Results of International Balloon Ascent, Dr. H. Hergesell, 66; the Report of the International Aeronautical | Society, 183 ; Experiments on best forms of Curves for use with Flying Machines, A. A. Merrill, 257; Mathematical Investigation of Theoretical Vertical Movements of Free | Balloon, Dr. Hergesell, 400; Death and Obituary Notice of Gaston Tissandier, 511; Death and Obituary Notice of Percy S. Pilcher, 546 Africa: Remarkable Meteorites at Mount Zomba, 85; the Harmattan Wind, Dr. von Danckelmann, 112; the Spring- buck ‘‘ Trek” in Cape Colony, C. Schreiner, 135 ; Eruptive Rocks of Cape Blanc, Algeria, and Duparc, E. Ritter, 144; Les Plantes Utiles du Sénégal, Le R. P. A. Sébire, J. M. Hillier, 148 ; Monkey Destruction on Gold Coast, R. Morley, 185 ; Mosquitoes and Malaria, Major Ronald Ross, 229, 398, 535, 574; Life History of the Parasites of Malaria, Major Ronald Ross, 322; the Cause and Prevention of Malaria, Major Ronald Ross, 357 ; West African Studies, Mary H. Kingsley, 243; Great and Small Game of Africa ; an Account of the Distribution, Habits, and Natural History of the Sporting Mammals, with Personal Hunting Experiences, 270; Cyclo- pean Ruins in Portuguese Africa, Dr. Karl Peters, 280; | Flora of Africa, 337; W. T. Thiselton-Dyer, F.R.S., 337 ; the Forests of the Sudan, Sir William Garstin, 401 ; the Vai Language, M. Delafosse, gor; Dr. Livingstone’s Tree, 425 ; the Extermination of Locusts by Fungus Inoculation, 426 ; Return of Major Ronald Ross, 574; Death and Obituary Notice of Dr. Oscar Baumann, 594; Death and Obituary Notice of Dr. J. W. Hicks, Bishop of Bloemfontein, 595 ; the Parent-Rock of the South African Diamond, Prof. T. G. Bonney, F.R.S., 620 Agamennone (G.), Methods of determining position of Epicentre in Distant Earthquakes, 46 Agriculture: Year-Book of the United States Department of Agriculture, 1898, 315 ; the West Indian Bulletin, 371 ; Agri- cultural Chemistry, Chimie végétale et agricole, M. Berthelot, 541; on the Chemical Effect on Agricultural Soils of the Salt Water Flood of November 29, 1897, on the East Coast, T. S. Dymond, 609; F. Hughes, 609; Official Report of the National Poultry Conference held at Reading in July 1899, 615 Air, the Audibility of Sound in, Rev. J. M. Bacon, 484 Air, Liquid, and the Liquefaction of Gases, T. O’Conor Sloane, 268 Aitken (R. G.), Double Star Catalogue, 354 Algebra, the Fundamental Principles of, Prof. Alexander Mac- farlane, 515 Algz, Iodine in Chlorophyll-containing, 336 Algae, Method of Preparing, for observation, 597 Algol Variable, the New, 354; New Variable of Algol Type,. M. Ceraski, 114; the New Algol Variable in Cygnus, 232, 442, 53 Allegheny Observatory, the New, 260 Allen (Dr.), the Squirrels North of Mexico, 537 Allen (Dr. F. J.), the Nature and Origin of Life, 623 Allen (W. J.), the Destruction of Orange-tree Pests by Fumiga- tion, 548 Alloys, Report of the Committee on the Heat of Combination of Metals in the Formation of, Prof. Vernon Harcourt, 586 Alpine Gardening, 6 Alps: Torsion Structure in the, M. Ogilvie, 443 Aluminium Iodide, Explosion of, Prof. P. L. Narasu, 520 Amagat (E. H.), New Form of Relations /(Z, v, T) = o for Fluids, 376 America: the Chief of the American Nautical Almanac, Prof. Wm. Harkness, 8; the Western Interior Coal-fields of America, H. F. Bain, 36; Bulletin of American Mathe- matical Society, 46, 117, 263, 308; American Journal of Mathematics, 90, 359; American Journal of Science, 117, 212, 383, 455, 516, 611; the Fresh-water Pearls of America, 150; Chapters on the Natural History of the United States, R. W. Shufeldt, 170; United States Geological Survey, 182; Recent Earth Movements of North American Lake Region, G. K. Gilbert, 182; ‘‘Amerind,” a Suggested Designation for American Aborigines, 188; Impressions of America, T. C. Porter, 291 ; a Problem in American Anthro- pology, Prof. Frederic Ward Putnam, 451; American Asso- ciation, 515 ‘* Amerind,” a Suggested Designation for American Aborigines, 188 Ames (J. P.), the Free Expansion of Gases, Memoirs by Gay- Lussac, Joule, and Joule and Thomson, 7 Ammon (Otto), Zur Anthropologie der Badener, 145 Amsterdam Academy of Sciences, 96, 216, 312 Anatomical Diagrams for the Use of Art Students, James M. Dunlop, 410 Anatomy: the Caéary avis common to all Mammalian Brains, Dr. Elliot Smith, 36; the Dog, its External and Internal Organisation, 435 Anderson (Dr. T. D.), Two New Variable Stars, 551 Armand Gautier, Prof. Suess, Dr. Maria Vi Index André (Ch.), a Remarkable Meteor, 408 ; Luminous Trains of Shooting Stars, 432 Andrews (C. W.), Geology of Christmas Island, 191 Animalium Index, C. Davies Sherborne, 174 Animals in Motion, E. Muybridge, 220 L’ Année Biologique, 195 Anomalurus, Myology of, F. C. Parsons, 118 Antarctica: the Work of the Belgian Expedition, Lieut. Gerlache, 13; the Soundings of the Aelevca, Henryk Arctowsky, 352; the Plans for Antarctic Exploration, 202 ; Government Grant in Aid of Antarctic Exploration, 256 Antelope, Larvae from the Head of an, Richard Crawshay, 150 ; Walter F. H. Blandford, 150 Anthrax Bacillus, Enzyme Negativing Action of, R. Emmerich and O. Low, 185 Anthropology: the Story of the British Race, John Munro, 52; the Origin of Religion, C. L. Henning, 135; Zur Anthropologie der Badener, Otto Ammon, 145 ; the Struggle between Peoples, Felix Regnault, 185; ‘‘Amerind” a Suggested Designation for American Aborigines, 188 ; Physical Measurements of Public Schoolboys, 198 ; the Winter Solstice Altars at Hano Pueblo, Dr. J. W. Fewkes, 258; the History of Mankind, Prof. Friedrich Ratzel, 269 ; Die Spiele der Menschen, Karl Groos, 363; Death and Obituary Notice of Dr. D, G. Brinton, 374; Three Crania rom Swiss Lake Sites, E. Pitard, 4o1; the Vai Language, M. Delafosse, 401 ; the Cambridge Anthropological Expedi- tion to Torres Straits and Sarawak, Prof. Alfred C. Haddon, F.R.S., 413; the Negritos; the Distribution of the Negritos in the Phillipine Islands and Elsewhere, Dr. A. B. Meyer, Prof. A. C. Haddon, F.R.S., 4333; a Problem in American Anthropology, Prof. Frederic Ward Putman, 451; Cave Shelters and the Aborigines of Tasmania, H. Ling Roth, 545 Anticyclones, Prevalence of, 366 Anti-Kathode, the Heating of the, in X-Ray Work, Dr. J. Macintyre, 1o1 Antiquities from the City of Benin, &c., in the British Museum, C. H. Read, O. M. Dalton, H. Ling Roth, 219 Ants, Harvesting, Prof. G. H. Bryan, F.R.S., 174 Apercus de Taxinomie Générale, J.-P. Durand (de Gros), 489 Appell (M.), on Rolling Motion, 384 Applied Geology, J. V. Elsden, 148 Apse Line of a Geminorum, Motion of, A. Belopolsky, 377 Arachnid: Maternal Devotion of Spiders, Francis J. Row- botham, 413 Archeology : Antiquities from the City of Benin in the British Museum, C. H. Read, O. M. Dalton, H. Ling Roth, 219; Cyclopean Ruins in Portuguese Africa, Dr. Karl Peters, 280 ; a Problem in American Anthropology. Prof. Frederic Ward Putnam, 451; Rock-Carving in Vancouver Island, 485 Arctica : the Glacial Phenomena of Spitzbergen, E. J. Garwood, 239; Death and Obituary Notice of Sir Alexander Armstrong, 257; Return of the Wellman Expedition, 399, 426; Bird Life in an Arctic Spring, the Diaries of Dan Meinertzhagen and R. P. Hornby, 542; Results of Lieutenant Peary’s Ex- plorations, 595 Arctowsky (Henryk), the Soundings of the Felezca, 352 Arithmetic: the New Science and Art of Arithmetic for the use of Schools, A. Sonnenschein and H. A. Nesbit, 7; a School Arithmetic, R. F. Macdonald, 7; the Arithmetic of Chemistry, John Waddell, 100 Arloing (S.), Influence of Manner of Introduction on Thera- peutic Effects of Anti-Diphtheritic Serum, 215 ; Preventive Qualities of Blood Serum of Immunised Heifer against Con- tagious Peripneumonia in Cattle, 636 Armstrong (Sir Alexander), Death and Obituary Notice of, 257 Armstrong (H. E.), Laws governing Substitution in Benzenoid Compounds, 214; on Laws of Substitution especially in Benzenoid Compounds, 609 ; Symbiotic Fermentation, 609 Arrhenius (Prof.), Causes of Secular Variations of Temperature at Earth’s Surface, 184 Arsonval (M. d’), Action of Gases on Caoutchouc, 239 Art Students, Anatomical Diagrams for the use of, James M. Dunlop, 410 Art of Topography, the, 101 Artificial Rearing of Young Sea-fish, W. Garstang, 631 Aschkinass (E.), Electric Oscillations and Moist Contacts, 117 Nature, December 14, 1899 Ashton (A. W.), Magnetic Hysteresis of Cobalt, 213 Asia: the Land of Rice, Taylor White, 8 Astertonella Formosa, G. C. Whipple and D. D. Jackson, 624 Astronomy : Scientific Worthies, Simon Newcomb, M. Loewy, 1 ; Our Astronomical Column, 18, 38, 63, 88, 114, 136, 161, 186, 207, 231, 260, 281, 301, 330, 354, 377, 402, 420, 442, 487, 513, 538, 551, 577; 597, 625; Second Washington Star Catalogue, 18 ; Spectra of Stars of Class III.4, Prof. W. C. Dunér, 18 ; Comet 1899a@ (Swift), 18, 38, 88, 114, 136, 161, 186, 260, 354; Prof. E. E. Barnard, 231; Prof. C. D. Perrine, 231; Comet 1898a (Swift), Herr H. Kreutz, 63; Tempel’s Comet 1899¢ (1873 II.), 18, 38, 114, 161, 186, 207, 232, 260, 281, 301, 330; M. L. Schulhof, 63; Saturn’s New Satellite, Prof. E. C. Pickering, 21; Primitive Constellations, R. Brown, jun., 31 ; on the Chemical Classification of the Stars, Sir Norman Lockyer, K.C.B., F.R.S., 52; on the Distribu- tion of the Various Chemical Groups of Stars, Sir Norman Lockyer, K.C.B., F.R.S., 617; Death of P. T. Main, 60; Holmes’ Comet 1899¢ (1892 III ), 161, 232, 281, 354, 377, 402, 429, 442, 487, 513, 577, 597, 625; Return of Holmes’ Comet (1892 III.), H. J. Zwiers, 63 ; Partial Eclipse of the Sun, June 7, 63; the Total Eclipse of the Sun, May 1900, C. H. Davis, 133; the Sun’s Heat, Prof. T. J. J. See, 4o2; the Rotation of the Sun, C. A. Schultz Steinheil, 577; the Main- tenance of Solar Energy, 615; Rotation Period of Mars, W. F. Denning, 64; Mars during Opposition 1898-1899, 330; New Star in Sagittarius, 88 ; Nova Sagittarii, 625 ; the New Algol Variable, 354; New Variable of Algol Type, M. Ceraski, 114 ; the New Algol Variable in Cygnus, 232, 442, 538; Lwo New Variable Stars, M. Luizet, 161; Dr. T. D. Anderson, 551; Southern Variable Stars, R. T. A. Innes, 513; Astronomical Occurrences in June, 114; in July, 207; in August, 301; in September, 429; in October, 5513 Motion of Apse Line of a Geminorum, A. Bélopol- sky, 377; the Royal Observatory, Greenwich, 136; White Spot on Jupiter, Ph. Fauth, 161; Fifth Satellite of Jupiter, Prof. E. E. Barnard, 207 ; the Red Spot on Jupiter, W. F. Denning, 210; Opposition of Jupiter, 1899, 597; Spectra of Red Stars (Class III. 6), Mr. Ellerman and Prof. G. E. Hale, 186; Spectra of Red Stars (Secchi’s Type IV.) Messrs. G, E. Hale and F. Ellerman, 429; Oxygen in Atmosphere of Fixed Stars, David Gill, F.R.S., 190; a Short History of Astronomy, Arthur Berry, 196 ; Oxford University Observatory, 207 ; Cambridge Observatory, 208 ; Gravitation in Gaseous Nebule, F. E. Nipher, 212; Maxima of Mira, A, A. Nyland, 232 ; the Life ofa Star, Prof. J. Perry, F.R.S., 247; Dr. T. J. J. See, 519 ; the New Allegheny Observatory, 260 ; Leeds Astronomical Society, 260 ; Theory of the Motion of the Moon, E. W. Brown, F.R.S., 260; the New Lunar Photographic Atlas, 491 ; Longitude from Moon Culmina- tions, D. A. Pio, 538; Annals of the Astronomical Observa- tory of Harvard, 266; Dynamical Theory ot Nebule, Dr. E. J. Wilczynski, 281 ; the Natal Observatory, E. Nevil, 28r ; Temperature changesin Yerkes Object-Glass, Prof. Barnard, 281; Stellar and Nebular Spectra with Concave Grating, 302 ; Photography of Nebule and Star Clusters, 330 ; Double Star Catalogue, R. G. Aitken, 354; Elements of Cometary Orbits, G. Fayet, 354; Mr. Tebbutt’s Observatory, 377; ‘Temperature in Gaseous Nebule, F. E. Nipher, 377; the Recent Perseid Meteoric Shower, W. F. Denning, 377 ; the Paris Observatory, 402; the Bulletin Astronomique, 402; Photometry of the Pleiades, Herrn G. Miiller and P, Kempf, 429; the System of Sirius, Herr H. J. Zwiers, 429; Cata- logue of Astronomical Instruments, Sir Howard Grubb, 430; Harvard College Observatory, Prof. Pickering, 442 ; Vana- dium in Meteorites, M. B. Hasselberg, 487 ; Cordoba Photo, graphs of Star-Clusters, 488 ; the Indian Eclipse, 1898, E.W; Maunder, 489; the Story of Eclipses, G. F. Chambers, 489 - The Bulletin de la Societe Astr. de France, 513 ; New Spec- troscopic Multiple Star, Prof. W. W. Campbell, 513 ; Stellar Parallax, Osten Bergstrand, 538 ; Precession Tables, Dr. Downing, 538; Histoire Abregée de l’Astronomie, Ernest Lebon, 543: the Melbourne Observatory Annual Report, P. Barrachi, 551; Comet Giacobini (1899 E) 551,577, 597; P. Chofardet, 612 ; the Polaris Multiple Star, Prof. W. W. Campbell, 577 ; Astronomical Camera Doublets, 578; Ob- servation of Leonids, 578; the Coming Shower of Leonids, W. F. Denning, 592 ; Law Connecting Motions in Planetary Variable Radial Velocity of ¢ Geminorum, 114; _ Nature, ] December 14, 1899, L[ndex vii System, Ch. V. Zenger, 597 ; Orbit of Eros, Herr Hans Osten, 625 ; Strassburg Observatory, 625 Astrosclera Willeyana, J. J. Lister, 631 Athénes, Annales de l’Observatoire National d’, publiées par Demetrius Eginitis, 266 Athens, Meteorology at, 157 Atkinson (E. H. de V.), Text-book of Practical Solid Geometry, 122 Atlantic Cable ; the Life Story of Sir Charles Tilston Bright : with which is Incorporated the Story of the Atlantic Cable and the first Telegraph to India, Edward Brailsford Bright and Charles Bright, 613 Atmospheric Railway, the South Devon, Sir Frederick Bram- well, 327-8 Atomic Weights, Proposal to Establish an International Com- mittee on, Prof. Tilden, 609 Atoms, on the Existence of Masses Smaller than the, Prof. J. Thomson, M. Broca, Prof. Riicker, Sir Norman Lockyer, Prof. Oliver Lodge, 586 Auden (H. A.), the Synthesis of Camphoric Acid, 214 Auerbach (Felix), Kanon der Physik, 314 Aurora, the Height of the, Prof. Cleveland Abbe, 130 Australasian Association, the, 82 Australia: Meteorology of South Australia, Sir Charles Todd, 134; in the Australian Bush and on the Coast of the Coral Sea: being the Experiences and Observations of a Naturalist in Australia, New Guinea and the Moluccas, Richard Semon, 169 Ayrton (Mrs. W. S.), the Reason for the Hissing of the Electric Arc, 282, 302 Babes (V), Prevention and Cure of Toxic Epilepsy by Injection of Normal Nerve Substance, 312 Backhouse (T. W.), Remarkable Lightning Flashes, 520 Bacon (Rev. J. M.), the Audibility of Sound in Air, 484 Bacteriology: Bacteria and Tobacco, G. C. Nuttall, 159; Enzyme Negativing Action of Anthrax Bacillus, R. Emmerich and O. Low, 185; a Polymorphous Bacterium, S. Hashi- moto, 185; Malaria and Mosquitoes, Prof. Grassi, 157 ; Major Ronald Ross, 229, 398, 535, 574; Prof. Koch, 595 ; Life-History of the Parasites of Malaria, Major Ronald Ross, 322; the Cause and Prevention of Malaria, Major Ronald Ross, 357; Investigations on Mosquitoes and Malaria, Dr. Daniels, 333; the Present Position of the Investigation of the Malarial Parasite, 439; Investigation of the Malarial Para- site, 546 ; Action of Quinine on the Parasite of Malaria, Dr. D. L. Monaco and L. Panichi, 576; Bacteria, Dr. George Newman, F.R.S., Dr. A. C. Houston, 434 Bacoucea (M.), Prevention and Cure of Toxic Epilepsy by In- jection of Normal Nerve Substance, 312 Baden, the Anthropology of, Otto Ammon, 145 Bailey (G. H.), Advanced Inorganic Chemistry, 76 Baillie (Charles William), Death and Obituary Notice of, 204 Bain (H. F.), the Western Interior Coal-field of America, 36 Baker (C. H.), a Gigantic Annual Plant, 485 Balance, Gravity, Quartz Thread, R. Threlfall and J. A. Pollock, 69 Balance, Gravity, a Portable, Profs. Threlfall and Pollock, 587 Balbiani (Prof.), Death of, 327 ; Obituary Notice of, 399 Baldwin (Prof. J. Mark), the Story of the Mind, 172 ; Heredity and Variation, 591 Balland (M.), Change of Flour-gluten with Age, 360 Balloons: Wireless Telegraphy between two, 278 ; Unmanned Balloon Ascent, 351 ; Mathematical Investigation of Theo- retical Vertical Movements of a Free Balloon, Dr. Hergesell, 400 Barcera (Mariano de la), Death of, 35 Barnard (Prof. E. E.), Fifth Satellite of Jupiter, 207; Comet, 1899 a (Swift), 231 ; Temperature Changes in Yerkes Object- glass, 281 Barnes (Prof. C. R.), Progress and Problems of Plant Physio- logy, 563 Barral (Et.), Preparation of Phenylic Chlorocarbonates, 240 Barrachi (P.), the Melbourne Observatory Annual Report, 551 Barrett (Prof. W. F., F.R.S.), Historical Note on Recalescence, 173; the Thermo-electric Properties of an Alloy Contain- ing Iron 68°8 per cent., Nickel 25-0, Manganese 5’0, and Carbon 12, 586 Barton (Dr.), Criterion for Oscillatory Discharge of Condenser, 70 Basset (A. B., F.R.S.), Bessel’s Functions, ror, 174 Bats and their Insect Prey, C. Oldham, 624 Baubigny (H.), the Separation of Traces of Bromine existing in Chlorides, 72; Separation and Estimation of Traces of Bromine in presence of large excess of Chlorides, 95 ; Estimation of Traces of Chlorine in presence of very large excess of Bromine, 143 Baumann (Dr. Oscar), Death and Obituary Notice, 594 Baxendell (J.), Self-recording Anemoscope, 215 Bay of Fundy, W. Bell Dawson, 161; Tides in the, Sir J. W. Dawson, F.R.S., 291; W. H. Wheeler, 461 Beasley (H. C.), Cast from Footprint in Stourton Trias, 143 Beattie (Prof. J. C.), Electrical Leakage from Charged Bodies, 95 Becquerel Rays, Profs. Elster and Geitel, 623, 635 Becquerel Rays and Magnetic Field, Profs. Elster and Geitel, 230 Beddard (Frank E., F.R.S.), a Note upon Phosphorescent Earthworms, 52 Bedeutung der Reize fiir Pathologie und Therapie im Lichte der Neuronlehre Die, De A. Goldschneider, 73 Bedford (F. P.), Gecko Cannibalism, 8 Bee-culture in United States, Frank Benton, 352 Beeton (Mary), Inheritance of Longevity in Man, 356 Békel (A.), Mixed Anhydrides of Formic Acid, 192 Belgian Antarctic Expedition, the Work of the, Lieut. Gerlache, 13; the Soundings of the Ae/gica, Henryk Arctowsky, 352 Bell (Ernest D.), Mammalian Longevity, 30 Belopolsky (A.), Motion of Apse Line of a Geminorum, 377 Beman (W. W.), New Plane and Solid Geometry, 517 Benham (Prof. Wm. Blaxland), the Development of the Tuatara, 79; the Skull of Hatteria, 567; Phosphorescent Earthworms, 591 Benin, Antiquities from the City of, in the British Museum, C. H. Read, O. M. Dalton, H. Ling Roth, 219 Benton (Frank), Bee Culture in United States, 352 Benzaldehyde, on the Action of Caustic Soda on, Dr. C. A. Kohn, 609; Dr. W. Trantom, 609 Benzenoid Compounds, on Laws of Substitution, especially in, Prof. Armstrong, 609 Bergens Museum, Report on Norwegian Marine Investigations, 1895-97, Dr. Johan Hjort, O. Nordgaard, and H. H. Gran, 313 Bérgstrand (Osten), Stellar Parallax, 538 Berlin Tuberculosis Congress (1899), Dr. 108, 154 Berry (Arthur), a Short History of Astronomy, 196 Berthelot (M.), the Formation of Alcohol by Plants, 167 ; Argon and its Combinations, 288 ; Combination of Sulphide of Carbon with Hydrogen and Nitrogen, 312; Ammoniacal Silver Nitrate, 384 ; Metallic Derivatives of Acetylene, 408 ; Reaction of Argon and Nitrogen with Mercury Alkyls, 408 ; Velocity of Detonations of Acetylene, 456; Chimie végétale et agricole, 541; Trimethylene, 564 Bertin (L. E.), Marine Boilers, 289 Bertrand (Gabriel), Properties of Dioxyacetone, 384 Bessel’s Functions, A. B. Basset, F.R.S., 101, 174; Prof. A Gray, F.R.S., 149 Bevan (E. J.), Oxidation of Furfural by Hydrogen Peroxide, 118 Bicycle; La Bicvclette, sa Construction et sa Forme, Dr. C. Bourlet, 77 Bidwell (Shelford, F.R.S.), Magnetic Strain in Bismuth, 222 ; Curiosities of Light and Sight, 389; Dark Lightning Flashes, F. W. Tunnicliffe, 591 Billow Clouds, Wave or, 235 Biology : a Biological Aspect of Cancer, F. J. Faraday, 23; Obituary Notice of Charles Naudin, 58; Results of the Scientific Expedition to Sokotra, 116; L’Année Biologique, 195; Thatsachen und Auslegungen in Bezug auf Regener- ation, August Weismann, 242 ; Die Methode der Variations- statistik, Georg Duncker, 338; the Soluble Ferments and Fermentation, J. Reynolds Green, F.R.S., 361; the Living Organism, an Introduction to the Problems of Biology, Alfred Earl, 458; Death of Johannes Miiller, Prof. Virchow, 595; the Nature and Origin of Life, Dr. F. J. Allen, 623 ; Marine Biology, Survey of Western English Channel, Walter Garstang, 157; an Account of the Deep Sea Ophiuroidea collected by the Royal Indian Marine Survey Ship Zzvestigator, R. Koehler, 459 Birds: Cries and Calls of Wild Birds, C. A. Witchell, 171; Habits of the Cuckoo, Wm. H. Wilson, 175; an Illustrated vill Manual of British Birds, Howard Saunders, 241 ; Bower- birds, A. J. Campbell, 275 ; Sedge-warblers Seizing Butter- flies, Oswald H. Latter, 520; Bird Life in an Arctic Spring : the Diaries of Dan Meinertzhagen and R. P. Hornby, 542 Bismuth; Magnetic Strain in, Shelford Bidwell, F.R.S., Dr. C. G. Knott, 222 Bjurholm Aerolite, the, 110 Blackford (Dr. Charles Minor), a Curious Salamander, 389 Blake (Dr. E. M.), Ruled Surfaces Generated by Plane Move- ments, whose Centrodes are Congruent Conics Tangent at Homologous Points, 359 Blake (H. W., F.R.S.), Death of, 229 Blake (R. F.), Amount and Causes of Carbonic Anhydride of Atmosphere, 94 Blandford (Walter F. H.), Larva from the Head of an Ante- lope, 150 Blatchford (T.), Geology of Coolgardie Goldfields, 300 Blondel (A.), Coherers, 87 Blondlot (R.), Electromotive Force Produced in Flame by Magnetic Action, 215 Blood, the Electrical Resistance of the, Dr. Dawson Turner, 24 Blood, Horse, Existence of a Preventive of Milk-coagulation in, A. Briot, 144 Bloxam (W. B.), Hydrosulphides, Sulphides and Polysulphides of Potassium and Sodium, 167 Blue Ray of Sunrise over Mont Blanc, Lord Kelvin, F.R.S., 411 Boas (Dr. Franz), Biological Significance of Cephalic Index, 442 Bock (A.), the Blue Steam Jet, 540 Boilers, Marine, L. E. Bertin, 289 Bollemont (E. G. de), Methylic, Ethylic and Amylic Cyan- acetates, 264 Bolletino della Societa Sismologica Italiana, 46, 237, 287 Bollingen (Dr.), Milk and Pigs as a Source of Tubercular In- fection to Mankind, 108 Bone (W. A.), Symmetrical Di-isopropylsuccinic Acid, 167 Bonetti (F.), Method of Determining Position of Epicentre in Distant Earthquakes, 46 Bonney (Prof. T. G., F.R.S.), Volcanoes : their Structure and Significance, 27 ; the Geology of Mont Blanc, 152; Theory of the Earth, with Proofs and Illustrations, James Hutton, 220; the Early Mountaineers, Francis Gribble, 274; the Parent-rock of the South African Diamond, 620 Bonnier (Gaston), Anatomical and Physiological Characters of Plants rendered Artificially Alpine, 71 Book of the Dead, the, E. A. Wallis Budge, 385 Books of Science, Forthcoming, 601 Bordage (E.), Regeneration of Front Pair of Appendages in Leaping Orthoptera, 312 Bordier (H.), Electrolytic Action in Neighbourhood of Crookes’ Tube, 216 Bore at Moncton, Bay of Fundy, the, W. Bell Dawson, 161 Bort (T. de), Temperature-variation of Free Air, 576 Bosphorus and Elsewhere, Investigations of Double Currents in the, Vice-Admiral S. Makaroff, 261 Botany : a Welsh Variety of Achlya Americana, A. H. Trow, 37; Morphology of Spore-producing Members. IV. Lepto- sporangiate Ferns, Prof. F. Bower, F.R.S., 46; Obituary Notice of Charles Naudin, 58; Journal of Botany, 67, 263, 488; Anatomical and Physiological Characters of Plants rendered artificially Alpine, Gaston Bonnier, 71 ; Mangroves Growing in Japan, Tokutaro Ito, 79; a Horn-destroying Fungus, Prof. H. M. Ward, F.R.S., 92; Linnean Society, 93, 118, 190, 214; the Flora of Cheshire, the late Lord de Tabley, 100 ; Spontaneous Asphyxia and Alcohol production in deeper Tissues of Ligneous Stems, H. Devaux, 143; Les Plantes Utiles du Sénégal Le R. P. A. Sébire, J. M. Hillier, 148; on Buds and Stipules, Right Hon. Sir John Lubbock, F.R.S., 149; the Formation of Alcohol by Plants, M. 3erthelot, 167; Mode of Impregnation in Lilium Martagon, M. Guignard, 185; Catalogue of the Library of the Royal Botanic Gardens, Kew, 244; Hybridisation, Dr. Maxwell T. Masters, F.R.S., 286; the International Conference on Hybridisation and Cross-Breeding, Wilfred Mark Webb, 305 ; Iodine in Chlorophyll-containing Algz, Armand Gautier, 336 ; ‘‘ Flora Capensis : being a Systematic Description of the Plants of the Cape Colony, Caffraria and Port Natal (and Neighbouring Territories), by Various Botanists, W. T. Thiselton-Dyer, F.R.S., 337; Flora of Tropical Africa, Index Nature, December 14, 1899 W. T. Thiselton-Dyer, F.R.S., 337; the Trinidad Cacao- Fungus, G. Massee, 353; the Improvement of the Sugarcane by Chemical Selection upon Sir William Thiselton-Dyer’s Method, 375; Anatomical Structure of Vanzlla aphylla, Edouard Heckel, 384 ; the Forests of the Sudan, Sir William Garstin, gor; Les Végétaux et les Milieux Cosmiques (Adaptation-Evolution), J. Constantin, 409; India-Rubber and the India-Rubber Industry, 426 ; New Algze, -Pleurococcus sulphurarius, Dr. A. Galdieri, 485; New Parasitic Tea- plant Disease, G. Massee, 485; a Gigantic Annual, C. H. Baker, 485; a Cross-bred Orchid, H. Peirson, 485; the Constant Difference between Normal and Adventitions Buds of Trees, C. de Candolle, 550; Progress and Problems of Plant Physiology, Prof. C. R. Barnes, 563 ; Phenomena of Cellular Disorganisation, V. Boulet, 564; Method of pre- paring Algz for Observation, 597; a Gutta-percha Plant capable of cultivation in Temperate Climate, MM. Dybowski and G. Fron, 612 ; Action of Anzesthetic Vapours on Dry and Moist Seeds, H. Coupin, 612; Astertonella formosa, D. D. Jackson, 624; Production of Mannose during Germination of Carob Seed, E. Bourquelot and H. Heérissey, 636 Boudouard (O.), Decomposition of Carbonic Oxide in presence of Metallic Oxides, 216; Decomposition of Carbonic Anhy- dride in presence of Carbon, 216 Boulder Pavement, a, G. K. Gilbert, 159 Boulet (V.), Phenomena of Cellular Disorganisation, 504 Boulvin (J.), the Entropy Diagram and its Application, 3 Bourlet (Dr. C.), La Bicyclette: sa Construction et sa Forme, 77 Bourquelot (E.), Pectins, 95 ; the Estimation of Mannose, 384 ; Composition of Carob Seed Albumen, 408; Production of Mannose during Germination of Carob Seed, 636 Bouty (E. J.), Do Rarefied Gases possess Electrolytic Conduc- tivity ? 312; Di-electric Cohesion of Rarefied Gases, 336 Bouveault (L.), Use of Tetrachlorohydroquinone for Characteri- sation and Separation of Fatty Acids, 264 Bower (Prof. F. O., F.R.S.), Morphology of Spore-producing Members IV. Leptosporangiate Ferns, 46 Bower-Birds, A. J. Campbell, 275 Boyle Lecture on the Perception of Musical Tone, the, Prof. McKendrick, 163 Bradford (J. R., F.R.S.), Organism of Tsetse Fly Disease, 309 Brain, the ; the Calcar Avis common to all Mammalian Brains, Dr. Elliot Smith, 36 Brain of Hermann von Helmholtz, the, 61 Bramwell (Sir Frederick), the South Devon Atmospheric Rail- way, 327-8 Branly (Edouard), Radioconductors with Metallic Spheres, 47 Brazilian Marmosets Breeding in England, Pair of, Dora Whitmore, 199 Breakell (Mr.), the Treatment of Refractory Silver Ores by Lixiviation, 15 Breitenbach (P.), Viscosity of Gases, 117 Breithaupt (G.), Optical Properties of Burnt-in Gold and Platinum Films, 212 Brenol (W. A.), the Story of Ice in the Present and Past, 615 Brewster (E. T.), Variation and Sexual Selection in Man, 4o1 Bright (Sir Charles Tilston), the Life Story of, with which is Incorporated the Story of the Atlantic Cable and the First Telegraph to India and the Colonies, Edward Brailsford Bright and Charles Bright, 613 Brinton (Dr. D. G.), Death and Obituary Notice of, 374 Briot (A.), Existence in Horse-blood of a Preventive of Milk- coagulation, 144 BRITISH ASSOCIATION: Dover Meeting of the, 463, 521; W. H. Pendlebury, 180, 370, 420, 495 ; Inaugural Address by Prof. Sir Michael Foster, K.C.B., Sec. R. S., President of the Association, 464; Evening Address ‘‘ La Vibration Nerveuse,” Prof. Charles Richet, 625 Section A (Mathematics and Phystcs).—Opening Address by Prof. J. H. Poynting, F.R.S., President of the Section, 470; Dr. Francis;Galton on ‘The Median Estimate,” 584; Prof. Forsyth on a System of Invariants for Parallel Configurations in Space, 5843; Prof. Everett on the Nota- tion of the Calculus of Differences, 584; Prof. A. C. Dixon on the Partial Differential Equation of the Second Order, 584; Dr. Irving Stringham on the Fundamental Differential Equations of Geometry, 584; Report on the Problem of Three Bodies, Mr. E. T. Whittaker, 585 ; on the Spectroscopic Examination of Contrast Phenomena, Nature December 14, “seuil Lndex ix Mr. G. J. Burch, Sir George Stokes, Principal Glazebrook, 585 ; Preliminary Results of a Research on the Variation of the Specific Heat of Water with Temperature, Prof. Callendar, 585 ; on a Flaw in Nernst’s Theory of Electro- lytic Solution Pressure, Dr. R. A. Lehfeldt, 585 ; on the Stability of an Ether containing long, thin, empty Vortex Filaments, Prof. Fitzgerald, 585; on the Absence of Hydrogen and Helium from the Earth’s Atmosphere, Prof. Bryan, 585; the Thermo-Electric Properties of an Alloy containing Iron 68°8 per cent., Nickel 25°0, Manganese 570, and carbon 1°2, Prof. W. F-. Barrett, 586; Report of the Committee on the Heat of Combination of Metals in the Formation of Alloys, Prof. Vernon Harcourt’s Criticism, 586 ; Preliminary Report of the Committee on Radiation from a Source of Light in a Magnetic Field, 586; on the Production in Rarefied Gases of Luminous Rings in Rota- tion about Lines of Magnetic Force, Mr. C. E. S. Phillips, 586 ; Note on Deep Sea Waves, Mr. V. Cornish, 586; on the Existence of Masses smaller than the Atoms, Prof. J. J. Thomson, M. Broca, Prof. Riicker, 586 ; Sir Norman Lockyer, Prof. Oliver Lodge, 587; Preliminary Results of a Year’s Work with the Seismograph at Mauritius, Mr. T. F. Claxton, 587 ; on the Progress Achieved during the Past Year at Blue Hill, Massachusetts, in the Exploration of the Air with Kites, Mr. A. L. Rotch, 587 ; the Hydro- Aérograph, F. Napier Denison, 587; a Portable Gravity Balance, Profs. Threlfall and Pollock, 587 ; Discussion on Platinum Thermometry, Prof. Callendar, Dr. J. A. Harker, Dr. Chappuis, Mr. E. H. Griffiths, Prof. Carey Foster, Prof. Burstall, Principal Glazebrook, Dr. Chree, Prof. Threlfall, Mr. W. N. Shaw, 587; on the Spectral Sensi- tiveness of Mercury Vapour in an Atmosphere of Hydrogen, Dr. E. P. Lewis, 587 Section B (Chemistry)—Opening Address by Dr. Horace T. Brown, F.R.S., President of the Section: Fixation of Carbon by Plants, 474; a Correction, 544; the Excretory Products of Plants, Prof. Hanriot, 608 ; Chemical Pro- cesses involved in the Saccharification of Starch by Malt- diastase, Dr. A. Fernbach, 608 ; on the Combined Action o Diastase and Yeast on Starch Granules, Dr. G. H. Morris, 608 ; the Action of Acids on Starch, Dr. G. H. Morris, 608; Symbiotic Fermentation, Prof. Marshall Ward, Sir Henry Roscoe, Prof. Armstrong, M. Van Laar, 609; Industrial Symbiotic Fermentations, Dr. Calmette, 609; Remarkable Result observed on the Exposure of Metallic Silver to Light, Colonel Waterhouse, 609 ; Pro- posal to Establish an International Committee on Atomic Weights, Prof. Tilden, 609; on Laws of Substitution, especially in Benzenoid Compounds, Prof. Armstrong, 609 ; Researches on Oxidation in Presence of Iron, Mr. Fenton, 609 ; Experiments on the Action of Hydrogen Peroxide on Carbohydrates in presence of Iron Salts, Messrs. Morrell and Crofts, 609; on the Influence of Solvents on the Optical Activity of Organic Compounds, W. J. Pope, 609 ; on the Action of Caustic Soda on Benzaldehyde, Drs. C. A. Kohn and W. Trantom, 609: on the Chemical Effect on Agricultural Soils of the Salt-water Flood of November 29, 1897, on the East Coast, Messrs. T. S. Dymond and F. Hughes, 609. Section C (Geology)—Opening Address by Sir Archibald Geikie, D.C.L., D.Sc., F.R.S., President of the Section, 496 ; Coal Exploration in Kent, R. Etheridge, Prof. W. Boyd Dawkins, 610; Investigations among the Upper Carboniferous Rocks of North Staffordshire, Mr. W. Gibson, 610; on a Recent Boring through the Chalk and Gault near Dieppe, A. L. Jukes-Browne, 610; the Origin of Flint, Prof. W. J. Sollas, 610; on Extra-morainic Drainage in Yorkshire, Prof. P. F. Kendall, 610; Homo- taxy and Contemporaneity, Prof. Sollas, 610; on a Smoothed and Grooved Surface of Mount Sorrel Granite underlying Undisturbed Keuper Marl, Prof. W. W. Watts, 610; Prof. A. Renard on the Origin of Chondritic Meteorites, 610; Prof. W. Boyd Dawkins on the Geology of the Channel Tunnel, 610; Mr. F. W. Harmer on a Proposed New Classification of the Pliocene Deposits of the East of England, 610; Mrs. M. M. (Ogilvie) Gordon on Sigmoidal Curves in the Earth’s Crust, 611. Sectzon D (Zoology)—Opening Address by Adam Sedgwick, M.A., F.R.S., President of the Section: Variation and Some Phenomena connected with Reproduction and Sex, 502; J. J. Lister on Astrosclera willeyana, 631; Prof. Johnson-Symington on the Morphology of the Cartilages of the Monotreme Larynx, 631; N. Bishop Harman, the Palpebral and Oculo-motor Apparatus in Fishes, 631 ; W. Garstang, First Report on the Periodic Investigation of the Plankton and Physical Conditions of the English Channel during 1899, 631 ; Dr. J. F. Gemmill on Negative Evidence regarding the Influence of Nutrition in Determining Sex, 631; Sir John Murray on Dr. Peterson’s Experiments in the Cattegat, with the Marking and Measuring of Plaice in order to determine Distribution and Growth, 631; W. Garstang on the Artificial Rearing of Young Sea-fish, 631 ; Prof. McIntosh on the Occurrence of the Grey Gurnard (Trigla gurnardus, L.) and its Spawning in Inshore and Off- shore Waters, 631 ; T. H. Taylor on the Embryolog of the Polyzoa, 631; Prof. MacBride on the Rearing of Larvee of Echinide, 631 Section E (Geography)—Opening Address by Sir John Murray, K.C.B,, F.R.S., LL.D., President of the Section, 521 Section G (Mechanical Sctence)—Opening Address by Sir William White, K.C.B., LL.D., F.R.S., President of the Section, 527 Section H (Anthropology)—Opening Address by C. H. Read, President of the Section, 554 Section I (Phystology)—Opening Address by J. N. Langley, F.R.S,, President of the Section, 557; Evening Address by Prof. Charles Richet, ‘‘ La Vibration Nerveuse,” 625 Section K (Botany)—Opening Address by Sir George King, K.C.I.E., LL.D., F.R.S., President of the Section: ‘* A Sketch of the History of Indian Botany, 581, 604 British Birds, an Illustrated Manual of, Howard Saunders, 241 British Medical Association, Meeting of the, at Portsmouth, Dr. F. W. Tunnicliffe, 341 British Race, the Story of the, John Munro, 52 Brizard (L.), Double Nitrite of Ruthenium and Potassium, 336 Broca (M.), on the Existence of Masses Smaller than the Atoms, 586 Brongniart (Dr. C.), Death of, 14 Brooks (A. H.), Age of Franklin White Limestone of Sussex County, New Jersey, 182 Brown (Ernest W.), Theory of the Motion of the Moon, 260 Brown (Dr. Horace T., F.R.S.), Opening Address in Section B of the British Association, ‘‘ Fixation of Carbon by Plants,” 474; a Correction, 544 Brown (R. junr.), Primitive Constellations, 31 Browning (Robert), and Meteorology, 245 Brouardel (Dr. P.), Progress during Past 100 Years, 510 Bruce (William S.), on the Use of the Fahrenheit Scale for Observations on Sea Temperatures, 545 ~ Bruyn (Prof. L. de), Influence of Water in Rapidity of Ether- formation, 312 Bryan (Prof. G. H., F.R.S.), Harvesting Ants, 174; the Volta Centenary Exhibition at Como, 181; on the Absence of Hydrogen and Helium from the Earth’s Atmosphere, 585 Bubble, Effect of Vibration on a Level, A. Mallock, 615 Buchanan (J. Y., F.R.S.), Meteorology of Ben Nevis in Clear and Foggy Weather, 311 ; Thermometric Scales for Meteoro- logical Use, 364 Biichner (Dr. Ludwig), Death of, 14 Budge (E. A. Wallis), the Book of the Dead, 385 Budgett (J. S.), Batrachians of Paraguayan Chaco, 513 Buds and Stipules, on, Right Hon. Sir John Lubbock, F.R.S., 149 Buguet (A.), Radio-graphic Bulb with Cold Antikathode, 636 Bukowski (G.), Geology of Southern Dalmatia, 135 Bulletin of American Mathematical Society, 46, 117, 263, 308 Bulletin Astronomique, 402 Bulletin de la Société Astr. de France, 513 Bunsen (Prof.), Death of, 398; Obituary Notice of, Sir Henry E. Roscoe, F.R.S., 424 Burbury (S. H., F.R.S.), Scoring at Rifle Matches, 412 Burch (G. J.), on the Spectroscopic Examination of Contrast Phenomena, 585 Burdon-Sanderson (Sir J., Bart., F.R.S.), the Relation of Motion in Animals and Plants to the Electrical Phenomena associated with it, 343 Burgess (G. K.), Method for determining Newtonian Constant, 432 Burghard (F. F.), a Manual of Surgical Treatment, 291 x Lndex Nature, December 14, 1809 Burstall (Prof.), Platinum Thermometry, 587 Burton (W.), Lead Compounds in Pottery Glazes, 18 Biitschli (O.), Untersuchungen iiber Strukturen, 124 Butterflies, Illustrations of Mimicry and Common Warning Colours in, Mark L. Sykes, 222 Butterflies, Sedge-Warblers seizing, Oswald H. Latter, 520 Cacao-Fungus, the Trinidad, G. Massee, 353 Calculation by Abacus, Maurice d’Ocagne, 363 Calculation, on the, of Differential Coefficients from Tables involving Differences, with an Interpolation Formula, W. F. Sheppard, 390 Calculus, the Origin of the Doctrine of Compensation of Errors in the Infinitesimal, Philip E. B. Jourdain, 245 Calculus of Differences, the Notation of the, Prof. Everett, 584 Callendar (Prof.), Preliminary Results of a Research on the Variation of the Specific Heat of Water with Temperature, 585; Platinum Thermometry, 587 Calmette (Dr.), Industrial Symbiotic Fermentation, 609 Cambridge Anthropological Expedition to Torres Straits and Sarawak, the, Prof. Alfred C. Haddon, F.R.S., 413 Cambridge Observatory, 208 Cambridge Philosophical Society, 119 Campbell (A. J.), Bower-Birds, 275 Campbell (Prof. E. D.), the Constitution of Steel, 403 Campbell (Prof. W. W.), New Spectroscopic Multiple Star, 513; the Polaris Multiple Star, 577 Camphoric Acid, the Synthesis of, H. A. Auden, W. H. Perkin, jun., and J. L. Rose, 214 Camus (L.), on State Refractory to Eel Serum, 336 Canada, Petrolenm in, Dr. G. M. Dawson, 159; the Bore at Moncton, Bay of Fundy, W. Bell Dawson, 161 ; the Devonian System of Canada, J. P. Whiteaves, 515 Cancer, a Biological Aspect of, F. J. Faraday, 23 Cancer, a Parasitic Fungus in Cancerous Tumours, J. Chevalier, 120 Candolle (C. de), the Constant Difference between Normal and Adventitious Buds of Trees, 550 Cannibalism, Gecko, F. P. Bedford, 8 Caoutchouc Threads, Transverse Tones of, V. von Lang, 384 Caoutchouc, Action of some Gases on, M. D’Arsonval, 239 Cape Observatory, the, 430 Carbohydrates, Experiments on the Action of Hydrogen Peroxide on, in Presence of Iron Salts, Mr. Morrell, 609 ; Mr. Crofts, 609 Carbon, Fixation of, by Plants, Dr. Horace T. Brown, F.R.S., 474, 544 ; Carbon Compounds, an Introduction to the, R. H. Adie, 271 Carlier (Dr. C. W.), Digestive Changes in Cells of Newt's Stomach, 95 Carpenter (George H.), Insects: their Structure and Life, 315 Carpenter (H. C. H.), Action of Ethylene and Trimethylene Dibromides on Sodium Derivative of Ethylic Cyanacetate, 118 Cartography: Leitfaden der Kartenentwurfslehre, Prof. Dr. Karl Zoppritz, Sir C. W. Wilson, F.R.S., 435 Carvell’s Nursery Handbook, J. M. Carvell, 518 Case (Edward), Death and Obituary Notice of, 536 Catalogue of Astronomical Instruments, Sir Howard Grubb, 430 Catslopue of the Lepidoptera of Northumberland, Durham, and Newcastle-upon-Tyne, J. E. Robson, 590 Catalogue of the Library of the Royal Botanic Gardens, Kew, 24. Garsteae Second Washington Star, 18 Cataloguing, a Manual of Library, J. Henry Quinn, 124 Cattle-Disease ; Preventive Qualities of Blood Serum of Im- munised Heifer against Contagious Peripneumonia, MM. S. Arloing and Duprez, 636 Cauro (J.), La Liquéfaction des Gaz, 490 Cause of Undercurrents, the, Admiral S. Makaroff, 544 Caustic Soda, on the Action on Benzaldehyde of, Dr. C, A. Kohn, 609 ; Dr. W. Trantom, 609 Cave Shelters and the Aborigines of Tasmania, H. Ling Roth, 4 Beenie and the Duration of the Human Race, T. E. Young, 73 Centenary of the Royal Institution, 129 Ceraski (M.), New Variable of Algol Type, 114 Chabaud (V.), Radio-graphic Bulb with Cold Antikathode, 636 Chalmers (R.), Gold Deposits of South Eastern Quebec, 428 Chambers (G. F.), the Story of Eclipses, 489 Channel, Western English, Survey of, Walter Garstang, 157 Channel, First Report on the Periodic Investigation of the Plankton and Physical Conditions of the, during 1899, W. Garstang, 631 Channel Tunnel, on the Geology of the, Prof. W. Boyd Dawkins, 610 Chaplin (Rt. Hon, H.), the Progress of Vaccination, 350 Chapman (D. L.), Allotropic Modifications of Phosphorus, 47 Chappius (Dr. P.), Comparison of Platinum and Gas Ther- mometers, 238 ; Platinum Thermometry, 587 Chapters on the Natural History of the United States, R. W. Shufeldt, 170 Characteristics of a University, on the, Prof. Riicker, F.R.S., 598 Charpentier (Dr. A. L.), Death of, 155 Chats about the Microscope, Henry C. Shelley, 518 Chattaway (F. D.), Series of Substituted Nitrogen Chlorides, 167 Chauveau (A.), Thermogenesis and Use of Energy of Man in Raising and Lowering His Own Weight, 360 Chauveau (A. B.), Diurnal Variation of Atmospheric Electricity, 564 Chemistry : the Temperature of Liquid Hydrogen, Prof. Dewar, 14 ; the Solidification of Hydrogen, Prof. Dewar, 456, 488 ; Solid Hydrogen, Prof. James Dewar, F.R.S., 514 ; Displace- ment of Mercury by Hydrogen, Albert Colson, 48; Ratio of Atomic Weights of Hydrogen and Oxygen, A. Leduc, 71 : the Flame of Hydrogen, MM. Schlagdenhauffen and Pagel, 72; Action of Hydrogen Peroxide on Carbohydrates in Presence of Iron, R. S. Morrell and J. M. Crofts, 47; Oxi- dation of Furfural by Hydrogen Peroxide, C. F. Cross, E. J. Bevan and T. Heiberg, 118; Hydrogen Peroxide and its Action on Photographic Plates, Dr. W. J. Russell, V.P.R.S., 208 ; Action of Hydrogen Peroxide on Formaldehyde, A. Harden, 214 ; Estimation of Hydrogen Phosphide in Gaseous Mixtures, A. Joannis, 143; Action of Phosphoretted Hydrogen on Copper and Copper Salts, E. Rubénovitch, 168, 384; the Oxides of Sodium and the Chemical Function of Water as compared with that of Hydrogen Sulphide, M. de Forcrand, 216; Decomposition of Silicates by Hydrogen Sulphide, P. Didier, 119; Combination of Sulphide of Carbon with Hydrogen and Nitrogen, Daniel Berthelot, 312 ; Osazones from Oxycelluloses, Léo Vignon, 24 ; Outlines of Industrial Chemistry, Frank Hall Thorp, 27; Recueil de données Numeriques Publié par la Société Francaise de Physique, Optique, H. Dufet, 28; Triboluminescence, Prof. A. S. Herschel, F.R.S., 29; Chemical Society, 47, 70, 118, 167, 214; Synthesis of 88’-dipyridyl Derivatives trom Citra- zinic Acid, W. J. Sell and H. Jackson, 47 ; Condensation of Oxalic Acid and Resorcinol, J. T. Hewitt and A. E. Pitt, 47; Ethyl Ammonium Sulphite, E. Divers and M. Ogawa, 47 ; Allotropic Modifications of Phosphorus, D. L. Chapman, 47; Terebic and Terpenylic Acids, W. T. Law- rence, 47; Fencholenic Acid, G. B. Cockburn, 47 ; Iodine in Sea Water, Armand Gautier, 47; A Crystallised Double Carbonate of Cerium Peroxide, André Job, 48 ; Supposed Fluorine in Mineral Waters, F. Parmentier, 48 ; Oxidising Power of Alkaline Periodates, E. Péchard, 48; On the Chemical Classification of the Stars, Sir Norman Lockyer, K.C.B., F.R.S., 52; On the Distribution of the Various. Chemical Groups of Stars, Sir Norman Lockyer, K.C.B., F.R.S., 617 ; Obituary Notice of Prof. Charles Friedel, Dr. J. H. Gladstone, F.R.S., 57 ; Silicomesoxalic Acid, Prof. Gattermann, 63 ; Combustion of Carbon Disulphide, H. B. Dixon and E. J. Russell, 70; Action of Nitric Acid on Nitrogen Peroxide, H. B. Dixon and J. D. Peterkin, 71 ; Mode of Burning of Carbon, H. B. Dixon, 71 ; Crystalline Glycollic Aldehyde, H. J. H. Fenton and H. Jackson, 71 ; the Blue Salt. of Fehling’s Solution, O. Masson and B. D. Steele, 71; New Compound of Arsenic and Tellurium, E. C. Szarwasy and C. Messinger, 71; the Enantiomorphously- Related Tetrahydroquinaldines, W. J. Pope andS. J. Peachey, 71 ; the Separation of Traces of Bromine existing in Chlorides, H. Baubigny, 72; Separation and Estimation of Traces of Bromine in presence of large excess of Chlorides, IH. Bau- higny, 95; Estimation of Traces of Chlorine in presence of very large excess of Bromine, H. Baubigny, 143 ; Action of Bromine in presence of Aluminium Chloride on Chloro- Nature, ] December 14, 1899 Index Xi Benzenes, A. Mouneyrat and Ch. Pouret, 636; Action of Bromine on Isobutyl Bromide in presence of Anhydrous Aluminium Bromide and Aluminium Chloride, A. Mouneyrat, 336; Magnesium Phosphide, H. Gautier, 72 ; Hydrogenation of Acetylene in presence of Nickel, Paul Sabatier and J. B. Senderens, 72; Metallic Derivatives of Acetylene, MM. Berthelot and Delépine, 408 ; Velocity of Detonations of Acety- lene, Daniel Berthelot and H. Le Chatelier, 456; Qualitative Chemical Analysis, Chapman Jones, 76; Practical Inorganic Chemistry for Advanced Students, Chapman Jones, 76; Advanced Inorganic Chemistry, G. H. Bailey, 76; The Spirit of Inorganic Chemistry, Arthur Lachman, 73; Ele- mentary Physics and Chemistry, Prof. R. A. Gregory and A. T. Simmons, 78; Simple Verification of Archimzedean Principle for Gases, P. Métral, 87 ; Amount and Causes of Variation of Carbonic Anhydride of Atmosphere, Prof. Letts and R. F. Blake, 94 ; Tungsten Pentabromide, Ed. Defacqz, 95; Mixed Halogen Salts of Lead, V. Thomas, 95; Activity of Manganese relatively to Phosphorescence of Strontium Sulphide, J. R. Mourelo, 95; Pectins, E. Bourquelot, 95 ; the Arithmetic of Chemistry, John Waddell, 100 ; Wiede- mann’s Annalen, 117, 212, 383, 456, 540, 635; Experiments with Endothermic Gases, W. G. Mixter, 117 ; Hypothetical Explanation of Partial Non-Explosive Combination of Explosive Gases and Gaseous Mixtures, W. G. Mixter, 117; Volatilisation of Iron Chlorides in Analysis and Separation of Oxides of Iron and Aluminium, F. A. Gooch and F. S, Havens, 117; Viscosity of Gases, P. Breitenbach, 117; Radius of Molecular Action, W. Mueller-Erzbach, 117; Corydaline (vi.), J. J. Dobbie and A. Lauder, 118 ; Action of Ethylene and Trimethylene Dibromides on Sodium Derivative of Ethylic Cyanacetate, H. C. H. Carpenter and W. H. Perkin, jun., 118; New Aldehyde Compounds of Camphor, A. Haller, 119 ; Di-Isoamylacetic Acid, H. Four- nier, 119; Fluorine in Mineral Waters, Charles Lepierre, 120; Molecular Refractions, Dispersion and _ Specific Rotatory Power of Combinations of Camphor with Aro- matic Aldehydes, A. Haller and P. T. Miiller, 167; Hydrosulphides, Sulphides and Polysulphides of Potassium and Sodium, W. P. Bloxam, 167 ; Dimethyl-pyrone Chloride, J. R. Collier and T. Tickle, 167 ; Symmetrical Di-isopro- pylsuccinic Acids, W. A. Bone and C. H. G. Sprankling, 167 ;. Active and Inactive Phenylalkyloxyacetic Acids, A. McKenzie, 167; Chemical Composition of Oleo-resin of Dacryodes hexandra, A. More, 167 ; Constitution of Tri- ethyl Orcintricarboxylate determined, D. S. Jerdan, 167; Series of substituted Nitrogen Chlorides, F. D. Chattaway and K. J. P. Orton, 167; Use of Potassium Chlorate in Explosives of Ammonium Nitrate Class. H. Le Chatelier, 168; Analysis of Croizat Spring Water, F. Parmentier, 168; Diazo-Compounds, New Method of carrying out Reaction, Dr. L. Gattermann, 186; Copper reduced at Low Temperature, A. Colson, 192; Mixed Anhydrides of Formic Acid, A. Béhal, 192; the Preparation of Hederine, M. Houdas, 192 ; Iodine in Royat Mineral Waters, A. Duboin, 192; Outlines of Physical Chemistry, A. Reychler, 197; School Laboratory Plans, Hugh Richardson, 199; A. E. Munby, 222, 292; T. S. Dymond, 245; Isomeric Salts of Hydrindamine containing Pentavalent Nitrogen, F. S. Kipping, 214 ; Organic Compound containing Silicon, F. S. Kipping and L. L. Lloyd, 214; Laws governing Substitution in Benzenoid Compounds, H. E. Armstrong, 214; the Decomposition of Chlorates, W. Sodeau, 214; Colouring Matter of Cotton Flowers, A. G. Perkin, 214 ; the Synthesis of Camphoric Acid, H. A. Auden, W. H. Perkin, jun., and J. L. Rose, 214; Dextro-ac-Tetrahydro-6-Naph- thylamine, W. J. Pope, 214; Resolution of Racemic Tetra- hydroparatoluquinaldine into optically-active Constituents, W. J. Pope and E. M. Rich, 214; Vapours emitted by Two Varieties of Mercuric Iodide, D. Gernez, 216; Decomposi- tion of Carbonic Oxide in Presence of Metallic Oxi les, O. Boudouard, 216; Decomposition of Carbonic Anhydride in Presence of Carbon, O. Boudouard, 216; a Lower Homo- logue of Citric Acid, Augustin Durand, 216; Crystallisation of Blood-Albumin, S. Gruzewska, 216 ; Practical Dictionary of Electrical Engineering and Chemistry in German, English and Spanish, Paul Heyne, Dr. E. Sanchez-Rosal, 221; Chemical Composition of Tetrahedrite, G. T. Prior and L. J. Spencer, 238; Preparation of Fluorine by Electrolysis in Copper Apparatus, Henri Moissan, 239 ; Action of Gases on Caoutchouc, M. d’Arsonval, 239; Temperature of Maximum Density of Aqueous Solutions of Alkali Chlorides, L. C. de Coppet, 240; Constitution of Oxides of Rare Metals, G. Wyrouboff and A. Verneuil, 240; Action of Ferric Chloride on Paradibromobenzene, V. Thomas, 240; Preparation of Phenylic Chlorocarbonates, Et Barraland Albert Morel, 240; Cerine and Friedeline, C. Istrati and A. Ostrogovich, 240 ; New Reactions of Indolic Bases and Albuminoid Compounds, Julius Gnezda, 240; Different Structural Forms of Diacetyl- succinic Ester, Prof. Knorr, 259; Condition of Dissolved Substances in Non-aqueous Solutions, A. F. Walden, 259 ; Variation of Iodine Compounds in Sea-water from different Depths, Armand Gautier, 264; Volumetric Estimation of Zinc, M. Pouget, 264 ; Preparation of Arsenides of Strontium, Barium and Lithium, P. Lebeau, 264; Methylic, Ethylic and Amylic Oxymethylene Cyanacetates, E. G. de Bollemont, 264; Use of Tetrachlorohydroquinone for Characterisation and Separation of Fatty Acids, L. Bouveault, 264; Soluble Animal Ferment reductive of Nitrates, E. Abelous and E. Gérard, 264; Reducing Power of Urine, H. Helier, 264; an Introduction to the Carbon Compounds, R. H. Adie, 271; Argon and its Combinations, Daniel Berthelot, 288 ; Reaction of Argon and Nitrogen with Mercury Alkyls, Daniel Berthelot, 408 ; Action of Nitric Oxide on Chromous Salts, M. Chesnau, 288; Metallic Sulphantimonites, M. Pouget, 288 ; an Oxyptomaine, O. de Coninck, 288; New Method for Acidmetric Estimation of Alkaloids, E. Faliéres, 288 ; Ben- zoyl-furfurane, R. Marquis, 288 ; the Egols, New General Anti- septics, E. Gautrelet, 288; Echidnase, C. Phisalix, 288; Lehrbuch der Anorganischen Chemie, Prof. Dr. H. Erdmann, 289; Tables . for Quantitative Metallurgical Analysis for Laboratory Use, J. James Morgan, 291; the Absorption of Nitrogen by Metals, Dr. Hempel, 297 ; Re- ducing Power of Extracts of Animal Organs, E. Abelous and E. Gérard, 312; Influence of Water on Ether-Formation, Prof. L. de Bruyn and Dr. A. Steger, 312 ; Photographic Researchés on Phosphorescent Spectra : on Victorium, a New Element associated with Yttrium, Sir William Crookes, F.R.S., 317; the Purification of Iridium, E. Leidié, 336 ; Double Nitrite of Ruthenium and Potassium, L. Brizard, 236; Oxidation of Propylglycol by Bromine Water, André Kling, 336; Dichlor-3°4-Butanoic Acid, R. Lespieau, 336 ; Analysis of Waters of Salt Lake of Urmi, R. F. Giinther and J. J. Manley, 359; Action of Magnesium on Saline Solu- tions, G. Lemoine, 360; Dissolution of Mercurdiammonium Iodide, Maurice Francois, 360; ‘Change in Flour Gluten with Age, M. Balland, 360; Physique et Chimie Viticoles, A. de Saporta, 364; Obituary Notice of Sir Edward Frank- land, K.C.B., F.R.S., 372; Ammoniacal Silver Nitrate, Messieurs Daniel Berthelot and Delépine, 384; Action of Chlorine on Mixture of Silicon, Silica and Aluminium, Emile Vigouroux, 384; the Estimation of Mannose, E. Bourquelot and H. Hérissey, 384 ; Production of Mannose during Ger- mination of Carob Seed, E. Bourquelot and H. Heérissey, 636 ; Properties of Dioxyacetone, Gabriel Bertrand, 384; Vari- ations in Production of Glycerol during Alcoholic Ferment- ation of Sugar, J. Laborde, 384; a Short History of the Progress of Scientific Chemistry in our own Times, Prof. W. A. Tilden, 387; Death of . Prof. Bunsen, 398; Obituary Notice of, Sir Henry E. Roscoe, F.R.S., 424; the Black Pottery Earths, H. Le Chatelier, 408 ; Action of Sodammonium and Potassammonium on Tellurium and Sulphur, C. Hugot, 408 ; Composition of Carob-seed Albumen, E. Bourquelot and H. Heérissey, 408 ; Estimation of Free Phosphorus in Oils and Fats, E. Louise, 408 ; Chemistry for Continuation Schools, R. L. Taylor, 411 ; Constitution of Tourmaline, F. W. Clarke, 455; Determin- ation of Tellurous Acid in presence of Halvid Salts, F. A. Gooch and C. A. Peters, 455; Iodometric Method for Estimation of Boric Acid, L. C. Jones, 456; Recommend- ations of Committee of American Chemical Society as to Chemical Measurements, 484 ; the Definition of the Element, Prof. F. P. Venable, 515 ; Explosion of Aluminium Iodide, Prof. P. L. Narasu, 520; the Blue Steam-Jet, A. Bock, 540; Trimethylene, Daniel Berthelot, 504 ; Electro-Chemical Fire-Alarm, 575 ; Two Chloro-bromides of Tungsten, E. Defacqz, 588 ; Copper Hypophosphite and its Decomposition by Precipitated Palladium, R. Engel, 588; Death of H. J. Kastner, 595; the Stereochemistry of Nitrogen, J. A. Le Bel, 612; the Reversible Liquefaction of Albuminoids, M. Xii Index Nature, December 14, 1899: Tsvett, 612; Volumetric Estimation of Quinones derived from Benzene, Amand Valeur, 612; Production of Ozone by Decomposition of Water with Fluorine, M. Moissan, 635 ; Heat of Oxidisation of Tungsten, MM. Delépine and Hallopeau, 636 ; Action of Potassium-Ammonium on Arsenic, C. Hugot, 636; Agricultural Chemistry: Chimie végétale et agricole, M. Berthelot, 541 Cheshire, the Flora of, by the late Lord de Tabley, 100 Chesnau (M.), Action of Nitric Oxide on Chromous Salts, 288 Chevalier (J.), A Parasitic Fungus in Cancerous Tumours, 120 Cheyne (W. Watson, F.R.S.), A Manual of Surgical Treatment, 291 Chicks, Experiments on, Dr, E. Thorndike, 112 Chief, the, of the American Nautical Almanac, Prof. Wm. Harkness, 8 Chinoy (Dr.), ee beter ae: Chofardet (P.), the Giacobini Comet (1899 e), 612 Chondritic Meteorites, on the Origin of, Prof. A. Renard, 610 Chree (Dr. C., F.R.S.), Collimator Magnets and Determination of Earth’s Horizontal Magnetism, 213 Chree (Dr.), Platinum Thermometry, 587 Christie (Richard Copley), the Presentation of the Freedom of the City of Manchester to, 578 Chronology, an Absolute Measure of Time based on Newtonian Constant of Gravitation, J. Lippmann, 400 Clark (William J.), Commercial Cuba, 7 Clarke (F. W.), Constitution of Tourmaline, 455 Classification: Apergus de Taxinomie Générale, J.-P. Durand (de Gros), 489 Claude (Georges), Magnetic Properties of Iron at Low Temper- atures, 432 Claxton (T. F.), Preliminary Results of a Year’s Work with the Seismograph at Mauritius, 587 Clayton (H. Helm), Thermometric Scales for Meteorological Use, 491 Climatology of Panama, General H. J. Abbot, 427 Clock-Rates and Barometric Pressure, Ensign Everett Hayden, 351 Clouds, Wave or Billow, 235 Coal: the Western Interior Coal-field of America, H. F. Bain, 36 Coal Exploration in Kent, R. Dawkins, 610 Cobalt, Magnetic Hysteresis of, Prof. Fleming, A. W. Ashton, and igh J. Tomlinson, 213 Cockburn (G. B.), Fencholenic Acid, 47 Cole (R. S.), Tee with a Liquid Surface studied by In- stantaneous Photography, 93 Collie (J. N.), Dimethyl-pyrone Chloride, 167 Collimator, Method of Setting a, G. Lippmann, 635 Columbia, the Ores of, H. W. Nichols, 442 Colour-Photography, the Diffraction Process of, Prof. R. W. Wood, 199 Colour-printing Machine, Ivan Orloff, 299 Colour Sensations in Terms of Luminosity, Captain W. de W. Abney, F.R.S., 237 Colours: Mimicry and Warning, Edward B. Poulton, F.R.S., 55; Prof. R. Meldola, F.R.S., 55 Colours in Butterflies, Illustrations of Mimicry and Common Warning, Mark L. Sykes, 222 Colson (Albert), Displacement of Mercury by Hydrogen, 48 ; Copper reduced at Low Temperature, 192 Comets : Comet 1899 a (Swift), 18, 38, 88, 114, 136, 161, 186, 260, 354, Prof. E. E. Barnard, 231 ; Prof. C. D. Perrine, 231 ; Comet 1898 a (Swift), Herr H. Kreutz, 63 ; Tempel’s Comet 1899 c (1873, II.), 18, 38, 114, 161, 186, 207, 232, 260, 281, 301, 330; M. L. Schulhof, 63; Holmes’ Comet 1899 d (1892, III.), 161, 232, 281, 354, 377, 402, 429, 442,'487, 513, 577, 597, 625; Return of Holmes’ Comet (1892, III.), H. J. Zwiers, 63 ; Elements of Cometary Orbits, G. Fayet, 354; Comet Giacobini (1899, E.), 551, 577, 597, P. Chofardet, 612 Commercial Cuba, William J. Clark, 7 Como, the Volta Centenary Exhibition at, F.R.S., 181 Compass, the Magnetic, and Nickel Cases, Rev. F. J. Jervis Smith, F.R.S., 173 Compensation of Errors in the Infinitesimal Calculus, the Origin of the Doctrine of, Philip E. B. Jourdain, 245 Concave Grating, Stellar and Nebular Spectra with, 302 Success of Indian Inoculation against Plague, Etheridge and Prof. W. Boyd Prof. G. H. Bryan, ‘Congress, Berlin Tuberculosis (1899), Dr. Conchology, Cowries of Caput-Serpentis Group, Melvill and Standen, 596 Conglomerate, Paleolithic Implements of Hertfordshire, Worth- ington G. Smith, 390 Messrs. F. W. Tunnicliffe, 108, 154 Congress, Science at the Women’s International, 228 Congress, the Seventh International Geographical, 227 Coninck (O. de), an Oxyptomaine, 288 Considére (M.), Variations of Volume in Portland Cement re- sulting from Setting and Hygrometric State, 540 Constantin (J.), Les Végétaux et les Milieux Cosmiques (Adaptation-Evolution), 409 Constellations, Primitive, R. Brown, jun., 31 Consumptives, Sanatoria for, in various parts of the World, F. Rufenacht Walters, 221 Continuation Schools, Chemistry for, R. L. Taylor, 411 Cook (J.), Polarisation Experiment, 8 Coolgardie Goldfields, Geology of, T. Blatchford, 300 Cooper (W. J.), Sewerage Analysis, 172 Coppet (L. C. de), Temperature of Maximum Density of Aqueous Solutions of Alkali Chlorides, 240 Cord (Ernest), Geology of the Lozeére, 135 Cordoba Photographs of Star-Clusters, 487 Cornish (V.), Deep-Sea Waves, 586 Cornu (Prof. A.), the Rede Lecture, the Wave Theory of Light, its Influence on Modern Physics, 292 Cordeaux (John), Obituary Notice of, 398 Cosmic Origin of Moldavite, the, 276 Country Schoolmaster, a, James Shaw, of Tynron, Dumfries- shire, 341 Coupin (H.), Action of Anzsthetic Vapours on Dry and Moist Seeds, 612 Cowries of Caput-Serpentis Group, Messrs. Melvill and Standen, 596 Craniology : Craniology of Hill Tribes of North-East Indian Frontier and of the Burmese, Prof. Sir W. Turner, 311 ; Improved form of Craniometer, Dr. Hepburn, 3113; Bio- logical Significance of Cephalic Index, Dr. Franz Boas, 442 Crawshay (Richard), Larve from the Head of an Antelope, 150 Cries and Calls of Wild Birds, C. A. Witchell, 171 Critical Pressure—a suggested New Definition, Dr. Jude, 412 Crofts (J. M.), Action of Hydrogen Peroxide on Carbohydrates. in Presence of Iron, 47; Experiments on the Action of Hydrogen Peroxide on Carbohydrates in Presence of Iron. Salts, 609 Crookes (Sir W., F.R.S.), new Photographic Researches on Phosphorescent Spectra, 44 Cross (C. F.), Oxidation of Furfural by Hydrogen Peroxide, 118 Cross-Breeding, the International Conference on Hybridisation and, Wilfred Mark Webb, 305 Crustacea, Mepluneopsis gilchrestt, a New Marine Gastropod,. G. R. Sowerby, 549 Cuba, Commercial, William J. Clark, 7 Cuckoo, Habits of the, Wm. H. Wilson, 175 Culminations, Moon, Longitude from, D. A. Pio, 538 Curliness of Hair, Natural, how Produced, Prof. Arthur Thom- son, 44 Currents, Double, in the Bosphorus and Elsewhere, Investiga- tions of, Vice-Admiral S. Makaroff, 261 Cyclone in Missouri, 14 Cyclopean Ruins in Portuguese Africa, Dr. Karl Peters, 280 Cygnus, the New Algol Variable in, 232, 442, 538 IRs Tale Dakyns (J. R.), Limestone Knolls in Craven District, 94 Dallas (James), Vole, 546 Dalton (O. M.), Antiquities from the City of Benin in the British Museum, 219 Daly (Chief Justice C. P.), Death of, 575 Danckelmann (Dr. von), the Harmattan Wind, 112 Daniels (Dr.), Investigations on Mosquitoes and Malaria, 333 Darbishire (Robert Dukinfield), the Presentation of the Free- dom of the City of Manchester to, 578 Darjeeling District, Earthquake in, 535 ; aster, Prof. J. Milne, F.R.S., 545 Darmstadt Museum, the, 164 the Darjeeling Dis- Lndex Xiil Nature, ] December 14, 1899. Dark Lightning Flashes, Apparent, Lord Kelvin, F.R.S., 341 ; Dr. William J. S. Lockyer, F.R.S., 391, 570; Prof. R. W. Wood, 460; Shelford Bidwell, F.R.S., 591; Ribbon and Dark Lightning, 423 Darwin, Reminiscences of, Sir Joseph D. Hooker, F.R.S., 187 Darwin (Horace), Expansion of Solids by Heat, 149 Data, Tables and, W. W. F. Pullen, 567 Davis (C. H.), the Total Eclipse of the Sun, May 1900, 133 Davis (J, and W.), the Larvze Collector’s Guide and Calendar, 244 Davis (Prof. W. M.), the Origin of Peneplains, 16 Davison (Dr. Charles), Spurious Earthquakes, 139; the Here- ford Earthquake of December 17, 1896, 194 Dawkins (Prof. W. Boyd), on the Geology of the Channel Tunnel, 610; Coal Exploration in Kent, 610 } Dawn of Reason, the, James Weir, 100 Dawson (Dr. G. W.), Petroleum in Canada, 159 Dawson (Sir J. W., F.R.S.), Tides of the Gulf and River St. Lawrence, and Bay of Fundy, 291 Dawson (W. Bell), the Bore at Moncton, Bay of Fundy, 161 Day (A. L.), the Gas Thermometer at High Temperatures, 516 Dead, the Book of the, E. A. Wallis Budge, 385 Dearborn (Dr. G. V. N.), the Emotions of Joy, 258 Debierne (A.), Radio-active Material from Pitchblende, 636 eee Exploring Expedition, United States, H. M. Smith, 37 Deep-Sea Ophiuroidea, an Account of the, collected by the Royal Indian Marine Survey Ship Zzwestégator, R. Koehler, 459 Deep-Sea Waves, V. Cornish, 586 Defacqz (Ed.), Tungsten Pentabromide, 95; Two Chloro- bromides of Tungsten, 588 Defective Eyesight, Dr. D. B. St. John Roosa, 341 Delafosse (M.), the Vai Language, 4or1 Delepine (M.), Ammoniacal Silver Nitrate, 384; Metallic Derivatives of Acetylene, 408 ; Heat of Oxidisation of Tungsten, 636 Bendy (Dr. A.), the Parietal Eye of New Zealand Tuatera, 104 Denison (F. Napier), the Hydro-Aérograph, 587 Denning (W. F.), Rotation Period of Mars, 64; the Red Spot on Jupiter, 210; the Recent Perseid Meteoric Shower, 377 Dentistry, the Hygiene of the Mouth, R. Denison Pedley, 172 Derby (O. A.), Argillaceous Rocks associated with Quartz Veins in Diamantina (Brazil) Region, 117 Devaux (H.), Spontaneous Asphyxia and Alcohol-production in Deeper Tissues of Ligneous Stems, 143 Dewar (Prof.), the Temperature of Liquid Hydrogen, 14; the Solidification of Hydrogen, 456, 488 ; Solid Hydrogen, 514 Diamond, the Parent-Rock of the South African, Prof. T. G. Bonney, F.R.S., 620 Diastase, Malt, Chemical Processes involved in the Sacchari- fication of Starch by, Dr. A. Fernbach, 608 Diastase and Yeast, the Combined Action on Starch Granules of, Dr. G. H. Morris, 608 Diatoms, Asterionella formosa, G. C. Whipple and D. D. Jackson, 624 Didier (P.), Decomposition of Silicates by Hydrogen Sulphide, 119 Diener (Prof. C.), the Depressions of the Northern Dolomites, 440 Dieppe, on a recent Boring through the Chalk and Gault near, A. L. Jukes-Browne, 610 Diet and Food considered in Relation to Strength and Power of Endurance, Training and Athletics, Alexander Haig, 73 Differential Coefficients, on the Calculation of, from Tables involving Differences with an Interpolation Formula, W. F. Sheppard, 390 Differential Equation, the Partial, of the Second Order, Prof. A. C, Dixon, 584 Differential Equations of Geometry, on the Fundamental, Dr. Irving Stringham, 584 Diffraction Process of Colour-Photography,' the, Prof. R. W. Wood, 199 Digestion, the Natural History of, A. Lockhart Gillespie, PRs 73 Dignet (Léon), the Formation of Pearls in Meleagrina margar- ztifera, 240 Diller (J. S.), Paleetrochis, 117 Discant (W. L.), Mimicry, 428 Dissociation Theory, on the Applicability of the, to the Electro- lysis of Aqueous Solutions containing two Electrolytes with a common Ion, J. G. McGregor, 86 Distant Sounds, W. F. Sinclair, 125 Divers (E.), Ethyl Ammonium Sulphite, 47 Dixon (Prof. A. C.), on the Partial Differential Equation of the Second Order, 584 Dixon (H. B.), Combustion of Carbon Disulphide, 70 ; Action of Nitric Oxide on Nitrogen Peroxide, 71; Mode of Burn- ing of Carbon, 71 Dobbie (J. J.), Corydaline, vi., 118 Doctrine of Compensation of Errors in the Infinitesimal Calculus, the Origin of the, Philip E, B. Jourdain, 245 Dodge (Raymond), Psychologische Untersuchungen iiber das Lesen, 172 Dog, the, its External and Internal Organisation, 435 Donaldson (John), Death of, 575 Double Currents in the Bosphorus and elsewhere, Investigations of, Vice-Admiral S. Makaroff, 261 Dover, Meeting of the British Association at, 463, 521; W. H. Pendlebury, 180, 370, 420, 495 ; Inaugural Address by Sir Michael Foster, K.C.B., Sec.R.S., President of the Association, 464 Downing (Dr.), Precession Tables, 538 Drawing, Geometrical, E. C. Plant, 122 Dreyer (Dr. J. L. E., F.R.S.), Giuvres Completes de Christian Huygens publiées par la Societé Hollandaise des Sciences, 457 Dublin Royal Society, 94 Duboin (A.), Iodine in Royat Mineral Waters, 192 Duddell (W.), Oscillograph for tracing Alternate-current Wave- forms, 77 Dufét (H.), Recueil de données Numeriques publié par la Société francaise de Physique, Optique, 28 Duncker (Georg), Die Methode der Variations statistik, 338 Dunlop (James), Anatomical Diagrams for the Use of Art Students, 410 Dunér (Prof. W. C.), Spectra of Stars of Class III.4, 18 Dupare (L.), Eruptive Rocks of Cape Blanc, Algeria, 144 ; Recherches Géologiques et Petrographiques sur le Massif du Mont Blanc, 152 Duporcq (E.), Premiers Principes de Géomeétrie Moderne, 314 Duprez (M.), Preventive Qualities of Blood Serum of Immunised Heifer against Contagious Peripneumonia in Cattle, 636 Durand (Augustin), a Lower Homologue of Citric Acid, 216 Durand (J. P.) (de Gros), Apercus de Taxinomie Générale, 489 Durham and Newcastle-upon-Tyne, Catalogue of the Lepi- doptera of Northumberland, J. E. Robson, 590 Dust-fall in Mediterranean, G. T. Prior, 205 Duties of Provincial Professors, the, 255, 292; Veritas, 316 Dybowski (M.), a Gutta-percha Plant capable of Cultivation in Temperate Climates, 612 Dymond (T. S.), School Laboratory Plans, 245; on the Chemical Effect on Agricultural Soils of the Salt Water Flood of November 29, 1897, on the East Coast, 609 Dynamics: a Treatise on the Dynamics of a Particle, Edward John Routh, F.R.S., 74; Dynamical Theory of Nebulz, Dr. E. J. Wilczynski, 281 Eakle (A. S.), Andesites from Fiji, 301 Earl (Alfred), the Living Organisms: an Introduction to the Problems of Biology, 458 Earth, Theory of the, with Proofs and Illustrations, James Hutton, Prof. T. G. Bonney, F.R.S., 220 Earth, the Theory of the Physics of the, P. Rudski, 623 Earth’s Atmosphere, on the Absence of Hydrogen and Helium from the, Prof. Bryan, 585 Earth’s Crust, the Sigmoidal Curves in the, Mrs. M. M. (Ogilvie) Gordon, 611 Earthquakes : Spurious Earthquakes, Dr. Charles Davison, 139; the Hereford Earthquake of December 17, 1896, Charles Davison, Prof. J.- Milne, F.R.S., 194; Relation between Hereford Earthquake of 1896 and Geological Structure of Bangor-Anglesey District, E. Greenly, 375; Earthquakes, Prof. C. G. Knott, 311; Prof. F. Omori on Earthquake- Motion, 431; Earthquake in Darjeeling District, 535; the Darjeeling Disaster, Prof. J. Milne, F.R.S., 545; Earth- quake in Ceram Island, 594 Earthworms, Phosphorescent, Prof. W. Blaxland Benham, 591 ; a Note upon, Frank E. Beddard, F.R.S., 52 XiV Index Nature, December 14, 1899 Ebert (H.), Law of Development of Hittorfs Dark Space, 635 Fchinidz, the Rearing of Larva of, Prof. MacBride, 631 Eclairage 4 Incandescence, |’, P. Truchot, 517 Eclipses : Partial Eclipse of the Sun, -June 7, 63; the Total Eclipse of the Sun, May 1900, C. H. Davis, 133; the Indian Eclipse, 1898, EF. W. Maunder, 489; the Story of Eclipses, G. F. Chambers, 489 Economic Entomology, 175 Edgecombe (Dr. Wilfrid), Why People go to Spas, 416 Edinburgh Chair of Physiology, the, 84 Edinburgh Mathematical Society, 215 Edinburgh Royal Society, 95, 191, 239, 311 Edington (Alexander), Red-Water or Texas Fever, 91 Edington’s (Dr.), Fungus-process for destroying Locusts, 16 Edser (Edwin), on the Phase-changes associated with the Reflection of Light from a Fuchsine Film, 44 ; Measurement and Weighing, 221; a Lecture Experiment on the Relative Thermal Conductivities of various Metals, 244 Education: Higher Education in Paris, A. T. Simmons, 10; Report of the London Technical Education Board, 141; Local University Colleges for London, 201; Science and Education, 324 ; Science Schools and Classes, 381 ; Chemistry for Continuation Schools, R. L. Taylor, 411; Sir Andrew Noble, F.R.S., on the Best Education for Engineers, 551, 568; Rural Education, John C. Medd, 616; Prof. R. Meldola, F.R.S., 616 Egg within Yolk of another, One Ilen’s, Mr. Herrick, 158 Eginitis (D.), Seismic Observations in Greece, 1893-8, 240; Annales de l’Observatoire National d’Athénes, publiées par, 266 Egyptology : the Book of the Dead, E. A. Wallis Budge, 385 Electricity : Wehnelt Interrupter, Dr. J. Macintyre, 8 ; Action of Wehnelt Interrupter, H. T. Simon, 383; Wehnelt’s Electrolytic Interrupter, A. Voller and B. Walter, 456; Experiments with Wehnelt’s Interrupter, E. Lecher, 456; Wireless Telegraphy, Prof. D. E. Hughes, 353; Oscil- lograph for Tracing Alternate-Current Wave-Forms, 44 ; Radio-constructors with Metallic Spheres, Edouard Branly, 47; an Improved Resistance-Box, 64 ; Luminosity of Rare Earths heated in vacuo by Kathode Rays, A. A. C. Swinton, 69 ; Kathode Rays, A. Wehnelt, 456, 576; Canaland Kathode Rays, P. Ewers, 635 ; Electrical Conductivity of Flames containing Salt Vapours, H. A. Wilson, 69 ; Criterion for Oscillatory Discharge of Condenser, Prof. W. B. Morton and Dr. Barton, 79; Quadrant Electrometer for application to Alternating Current Measurements, Mr. Addenbrooke, 70; an Intense Source of Monochromatic Light, Ch. Fabry and A. Perot, 71; Rontgen Rays and Convection Currents, John Zeleny, 86; Influence of Gaseous Pressure on Electric Currents due to Rontgen Rays, W. Hillers, 383 ; on the Applicability of the Dissociation Theory to the Electrolysis of Aqueous Solu- tions containing Two Electrolytes with a Common Ion, J. G. McGregor, 86 ; Diffusion of Ions into Gases, J. S. Townsend, 212 ; Comparative Efficiency of Condensation Nuclei of Posi- tively and Negatively Charged Ions, C. T. R. Wilson, 238; the Nature of Electric Sparks, B. Walter, 87 ; Coherers, A. Blondel, 87; Quantitative Investigation of Coherer, New Spectroscopic Multiple Star, Prof. W. W. Campbell, 513; Stellar Parallax, Osten Bergstrand, 538; Stellar and Nebular Spectra with Concave Grating, 302; the Polaris Multiple Star, Prof. W. W. Campbell, 577 Statistical Methods applied to Biology, 338 Steam Navigation, Sir William White, K.C.B., LL.D., F.R.S., 27 Steele (B.D.), the Blue Salt of Fehling’s Solution, 71 Steger (Dr. A.), Influence of Water on Ether Formation, 312 Steinheil (C. A. Schultz), the Rotation of the Sun, 577 Stellar Parallax, Osten Bergstrand, 538 Stellar and Nebular Spectra with Concave Grating, 302 Sterilisation of Potable Waters by Ozone, MM. Marmier and Abraham, 24 Stevens (H. S.), an Elementary Course of Mathematics, 518 Stipules, on Buds and, Right Hon. Sir John Lubbock, F.R.S. , 14 Bistes (Sir George Gabriel, F.R.S.), the Jubilee of, rog, 125 Strain in Bismuth, Magnetic, Shelford Bidwell, F.R.S., Dr. C. G. Knott, 222 Strassburg Observatory, 625 Strawberry Cure for Gout, 125 ; Donald Ferguson, 150 Stringham (Dr. Irving), on the Fundamental Differential Equations of Geometry, 584, Stromeyer (C. E.), Induced Lightning Flash, 511 ; Remark- able Lightning Flashes, 520 Stroud (Prof. Henry), Remarkable Lightning Flashes, 520 Nature, J December 14, 1899 Lndex XXXII Strukturen, Untersuchungen iiber, O. Biitschli, 124 Stuart-Menteath (Charles G.), Is Insusceptibility to Vaccine produced by Small-pox, 436 Subjective Impressions due to Retinal Fatigue, W. J. Millar, I Substitution, on Laws of, especially in Benzenoid Compounds, Prof. Armstrong, 609 Sudan, the Forests of the, Sir William Garstin, 401 Suess (Prof.), Torsion Structure in the Alps, 443 Sugar Cane, the Improvement of the, by Chemical Selection upon Sir W. Thiselton-Dyer’s Method, 375 Sun: Partial Eclipse of the, June 7, 63; the Total Eclipse of the Sun, May 1900, C. H. Davis, 133; the Sun’s Heat, Prof. T. J. J. See, 402; Blue Ray of Sunrise over Mont Blanc, Lord Kelvin, F.R.S., 411; the Indian Eclipse 1898, E. W. Maunder, 489 ; the Story of Eclipses, G. F. Chambers, 489 ; the Rotation of the Sun, C. A. Schultz Steinheil, 577; the Maintenance of Solar Energy, 615 Sundorph (T.), Cause of Change in Conductivity of Metallic Powder, 456 Supan (Dr.), the Results of the Va/dvia Expedition, 114 Surgery: Obituary Notice of Surgeon-Major G. C. Wallich, 13; a Manual of Surgical Treatment, W. Watson Cheyne, F.R.S., and F. F. Burghard, 291 ; Surgery and the Rontgen Rays, Dr. C. M. Moullin, 426 Swift’s Comet (1899 a), 18, 38, 88, 114,:136, 161, 186, 260, 354, Prof. E. E. Barnard, 231 ; Prof. C. D. Perrine, 231 Swinton (A. A. C.), Luminosity of Rare Earths heated in Vacuo by Kathode Rays, 69 ; an Improved Liquid Interrupter for Induction Coils, 226 Switzerland: Visit of the Institution of Electrical Engineers to Switzerland, Prof. Richard Threlfall, F.R.S., 578 Sykes (Mark L.), Natural Selection in the Lepidoptera, 222 Symbiotic Fermentation, Prof. Marshall Ward, 609; Sir Henry Roscoe, 609; Prof. Armstrong, 609; M. Van Laar, 609 ; Industrial Symbiotic Fermentation, Dr. Calmette, 609 Symington (Prof. Johnson), on the Morphology of the Car- tilages of the Monotreme Larynx, 631 Symons (Mr.), Meteorological Extremes, 308; Influence of Altitude on Rainfall, 400 Symons’s Monthly Meteorological Magazine, 90, 212, 308 Szarvasy (E. C.), New Compound of Arsenic and Tellurium, 71 Szily (Coloman de), Effect of Torsion on Resistance of Wires, 352 Tables and Data, W. W. F. Pullen, 567 Tables, Mathematical, James P. Wrapson, W. W. Haldane Gee, 590 Tables, Precession, Dr. Downing, 538 Tabley (the Late Lord de), the Flora of Cheshire, 100 Taff (J. A.), an Albertite-like Asphalt, 516 Tait (Prof. Peter Guthrie), Scientific Papers, 98 Tammann (G.), Limits of Solid State, 540 Tasmania, Cave Shelters and the Aborigines of, H. Ling Roth, 4 Tea vem : Apercus de Taxinomie Générale, J. P. Durand (de Gros), 489 Taylor (A. E.), Psychologische Untersuchungen iiber des Lesen, 172 ; the Story of the Mind, 172 Taylor (R. L.), Chemistry for Continuation Schools, 411 Taylor (T. H.), on the Embryology of the Polyzoa, 631 Tchistovitch (Dr. T. H.), the Mechanism of Immunity, 302 Tebbutt’s (Mr.), Observatory, 377 Technical Education: Report of the London Technical Educa- tion Board, 141 Telegony, Experimental Investigations in, Prof. J. C. Ewart, F.R.S., 330 Telegraphy: the Life Story of the late Sir Charles Tilston Bright, with which is incorporated the Story of the Atlantic Cable and the First Telegraph to India and the Colonies, Edward Brailsford Bright and Charles Bright, 613 Telegraphy, a new System of, 548 Telegraphy, Wireless, Prof. D. E. Hughes, 35 Telegraphy, Wireless, between two Balloons, 278 Telescopy: Method of Setting a Collimator, G. Lippmann, 35 Tempel’s Comet 1899 ¢ (1873 II.), 18, 38, 114, 161, 186, 207, 232, 260, 281, 301, 330, M. L. Schulhof, 63 Peigeemare Changes in Yerkes Object-glass, Prof. Barnard, 281 Temperature, Preliminary Results of a Research on the Nenatee of the Specific Heat of Water with, Prof. Callendar, 595 Temperature, Causes of Secular Variations of, at Earth’s Surface, Prof. Arrhenius, 184 Temperature—Entropy Diagram, the, J. Boulvin, Prof. John Perry, F.R.S., 3 Temperatures in Gaseous Nebule, F. E. Nipher, 377 Tennant (W. J.), the Slide Valve Simply Explained, 149 Terrestrial Gegenschein, the, Prof. S. Newcomb, 544 Thatsachen und Auslegungen in Bezug auf Regeneration, August Weismann, 242 Theory of the Earth, with Proofs and Illustrations, James Hutton, Prof. T. G. Bonney, F.R.S., 220 Theory of Reality, a, Prof. George Trumbull Ladd, 270 Therapeutics : Why People go to Spas, Dr. Wilfrid Edgecombe, 416 Thermal Conductivities of Various Metals, a Lecture Experi- ment on the Relative, Edwin Edser, 244 Thermodynamics: the Entropy Diagram and its Applications, J. Boulvin, Prof. John Perry, F.R.S., 3 Thermo-electric Properties of an Alloy containing Iron 68°8 per cent., Nickel 25:0, Manganese 5°0, and Carbon 1°2, Prof. W. F. Barrett, 586 Thermometers, Comparison of Platinum and Gas Thermometers, Drs. J. A. Harker and P. Chappius, 238 Thermometers, on the Use of the Fahrenheit Scale for Observ- ations on Sea Temperatures, William S. Bruce, 545 Thermometric Scales for Meteorological Use, J. Y. Buchanan, F.R.S., 364; H. Helm Clayton, 491 Theim (Dr.), the Ignition of Fire-damp by Electricity, 350 Thiselton-Dyer (Sir William, F.R.S.), Flora Capensis : being a Systematic Description of the Plants of the Cape Colony, Caffraria and Port Natal (and Neighbouring Territories) by Various Botanists, 337 ; Flora of Tropical Africa, 337; the Improvement of the Sugar-Cane by Chemical Selection upon the Method of, Sir William Thiselton-Dyer, 375 Thomas (V.), Mixed Halogen Salts of Lead,g5; Action of Ferric Chloride on Paradibromobenzene, 240 Thompson (Mrs. Elizabeth), Death of, 350 Thompson (J. O.), Experiments on Fatigue of Metals, 86 Thompson (Silvanus P., F.R.S.), Michael Faraday, his Life and Work, 123 Thomson (Prof. Arthur), How Natural Curliness of the Hair is Produced, 44 Thomson (Prof. Elihu), the Field of Physical Experimental Research, 515 Thomson (Prof. J. J.), on the Existence of Masses smaller than the Atoms, 586 Thorndike (Dr. E.), Experiments on Chicks, 112 Thorne (Sir Richard Thorne, K.C.B., F.R.S.), the Ad- ministrative Control of Tuberculosis, 73 Thornhill (Mark), Haunts and Hobbies of an Indian Official, 5 Thorp (Frank Hall), Outlines of Industrial Chemistry, 27 Thorpe (Prof. T. E., F.R.S.), Lead Compounds in Pottery Glazes, 18 Three Bodies, Report on the Problem of, E. T. Whittaker, 584 Threlfall (Prof. R., F.R.S.), Quartz Thread Gravity Balance, 69; a Portable Gravity Balance, 587; Visit of Institution of Electrical Engineers to Switzerland, 578; the Rheinfelden Power Station, 579; the Oerlikon Power Works, 579; the Selnau Transformer Station, 579; the Ziirich Polytechnicum, 580; the Kander Power Station, 580; the Burgdorf-Thun Railway, 580; Platinum Thermometry, 587 “Thunder”’-storm, the so-called ; Prevalence of Anticyclones, 366 Tick-Fever, Protective Inoculation against, Frank Tidswell, 62 Tickle (T.), Dimethyl-pyrone Chloride, 167 Tides: the Bore at Moncton, Bay of Fundy, W. Bell Dawson, 161; Tides of the Gulf and River St. Lawrence and Bay of Fundy, Sir J. W. Dawson, F.R.S., 291 ; Tides in the Bay of Fundy, W. H. Wheeler, 461; the Tides Simply Explained with Practical Hints to Mariners, Prof. J. H. S. Moxly, 340 Tidswell (Frank), Protective Inoculation against Tick-fever, 62 Tilden (Prof. W. A.), a Short History of the Progress of Scien- tific Chemistry in our own Times, 387 ; Proposal to establish an International Committee on Atomic Weights, 609 XXXIV Index Nature, December 14, 1899 Time, Geological, Rev. O. Fisher, 544 Tin Trade of Prehistoric Europe, the, Salomon Reinach, 596 Tissandier (Gaston), Death and Obituary Notice of, 511 Tobacco, Bacteria and, G. C. Nuttall, 159 Todd (Sir Charles), Meteorology of South Australia, 134 Todhunter (I., F.R.S.), the Elements of Euclid, 290 Tomlinson (H. J.), Magnetic Hysteresis of Cobalt, 213 Top, Mathematics of the Spinning, F. Klein and A. Sommer- feld, 319, 346; Prof. A. G. Greenhill, F.R.S., 319, 346, 391 Topography, the Art of, ror Tornadoes, J. R. Musick, Prof. Cleveland Abbe, 328 Torpedoes, Ether Wave Apparatus for Directing, Walter Jamie- son and John Trotter, 85 Torres Straits and Sarawak, the Cambridge Anthropological Expedition to, Prof. Alfred C. Haddon, F.R.S., 413 Torsion Structure in the Alps, Prof. Suess and Dr. Maria M. Ogilvie, 443 Tortoises, the Giant, of the Galapagos, W. Herbert Purvis, 199 Townsend (J. S.), Diffusion of Ions into Gases, 212 Transmission, a Measure of the Intensity of Hereditary, Francis Galton, F.R.S., 28 Transparency and Opacity, the Right Hon. Lord Rayleigh, F.R.S., 64 Trantom (Dr. W.) on the Action of Caustic Soda on Benzalde- hyde, 609 Travels in New Guinea, H. Cayley Webster, 49 Triboluminescence, Prof. A. S. Herschel, F.R.S., 29 Trinidad Cacao-Fungus, the, G. Massee, 353 Trotter (John), Ether Wave Apparatus for directing Torpedoes, 8 sree (A. H.), a Welsh Variety of Achlya amerzcana, 37 Trowbridge (A.), Quantitative Investigation of Coherer, 516 Trowbridge (J.), Explosive Effect of Electrical Discharges, 611 Trucot (P.), L’éclairage 4 Incandescence, 517 Tsetse Fly Disease, Organism of, H. J. Plimmer and J. R. Bradford, F.R.S., 309 Tsvett (M.), the Reversible Liquefaction of Albuminoids, 612 Tuatara, the Development of the, Prof. Wm. Blaxland Benham, 79; the Parietal Eye of New Zealand Tuatara, Dr. A. Dendy, 184 i Tuberculosis, the Administrative Control of, Sir Richard Thorne Thorne, K.C.B., F.R.S., 73 ; Berlin Tuberculosis Congress (1899), Dr. F. W. Tunnicliffe, 108, 154; Milk and Pigs asa Source of Infection to Mankind, Dr. Bollingen, 108 ; Relation of Tubercle Bacillus to Tuberculosis, Prof, Fliigge, 109 ; Nature and Modus operandi of Infection, Prof. C. Frankel, 109; Mixed Infection, Prof. Pfeiffer, 109; Heredity and Tuberculosis, Prof. Loffler, 109 ; Presence of Tubercle Bacillus in Berlin Market Milk and Butter, Dr. K. Obermiiller, 109; Tubercle Infection from Cows, Drs. Rabinowitsch and Kempner, 206 ; Zoological Distribution of Tuberculosis, Dr. W. Hutchinson, 215 ; Sanatoria for Consumptives in various Parts of the World, F. Rufenacht Walters, 221 Tunnicliffe, (Dr. F. W.), Berlin Tuberculosis Congress (1899), 108, 154; Meeting of the British Medical Association at Portsmouth, 341 Turner (Dr. Dawson), the Electrical Resistance of the Blood, 245 Turner (H. W.), Rosccelite, 212 Turner (Prof. Sir W.), Craniology of Hill Tribes of North-east Indian Frontier and of the Burmese, 311 Tutton, (A. E.), Thermal Expansion of Pure Nickel and Cobalt, 93 Tyrrell (J. B.), the Klondyke Gold Field, 159 Under-currents, Rear-Admiral Sir W. J. L. Wharton, K.C.B., F.R.S., 316 Under-currents, the Cause of, Admiral S. Makaroff, 544 Underground Fires, the Extinguishment by Carbonic Acid Gas of, George Spencer, 375 United States: Chapters on the Natural History of the United States, R. Shufeldt, 170; United States Geological Survey, 182; the United States National Museum, 225 ; the Proposed Magnetic Survey of the United States, 235 ; Year-Book of the United States Department of Agriculture (1898), 315; Bee Culture in the United States, Frank Benton, 352; United States Deep-Sea Exploring Expedition, H. M. Smith, 378 Universities : Higher Education in. Paris, A. T. Simmons, 10; University Intelligence, 22, 44, 65, 90, 117, 141, 164, 189, 211, 237, 263, 287, 307, 335, 358, 382, 407, 431, 455, 488, 516, 539, 563, 588, 611, 634; Local University Colleges for London, 201; the University of London, 246, 325; the Housing of the Offices of the University of London, 232 ; on the Characteristics of a University, Prof. Riicker, F.R.S., 598 Unscientific Notes, 5 Urmi Salt Lake, Physical and Chemical Investigation of Waters of, R. T. Giinther and J. J. Manley, 359 Vaccination, the Progress of, Right Hon. H. Chaplin, 350 Vaccine : Is Insusceptibility to, produced by Small-pox, Charles G. Stuart-Menteath, 436; Prof. G. Sims Woodhead, 436 Vai Language, the, M. Delafosse, gor Valdivia Expedition, the Results of the, Dr. Supan, 114 Valeur (Amand), Volumetric Estimation of Quinones derived from Benzene, 612 Vallentin (Rupert), the Sea-Elephant, 190 Vanadium in Meteorites, M. B. Hasselberg, 487 Vancouver Island, Rock Carving in, 485 Variable Stars: Variable Radial Velocity of ¢ Geminorum, 114 ; the New Algol Variable, 354; M. Ceraski, 114; Two New Variable Stars, M. Luizet, 161; Dr. T. D. Anderson, 551 ; New Algol Variable in Cygnus, 232, 442, 538 ; New Spectro- scopic Multiple Star, Prof. W. W. Campbell, 513 ; Southern Variable Stars, R. T. Innes, 513 ; the Polaris Multiple Star, Prof. W. W. Campbell, 577 Variation, Heredity and, Prof. J. Mark Baldwin, 591 Variation and some Phenomena connected with Reproduction and Sex, Adam Sedgwick, M.A., F.R.S., 502 Variation and Sexual Selection in Man, E. T. Brewster, 401 Variation of Species, J. W. Sharpe, 102 Variationsstatistik, die Methode der, Georg Duncker, 338 Vast (A.), Action of Toluylene- Diamine on Red Blood Corpuscles, Vegétaux, les, et les Milieux Cosmiques (Adaptation-Evolution), J. Constantin, 409 Venable (Prof. F. P.), the Definition of the Element, 515 Verneuil (A.), Constitution of Oxides of Rare Metals, 240 Verworn (Max), General Physiology, 565 Vibrating Strings, Beats given by, C. Maltézos, 456 Vibration, Effect of, on a Level Bubble, A. Mallock, 615 Victorium, on, a New Element associated with Yttrium, Sir William Crookes, F.R.S., 317 Views on some of the Phenomena of Nature, James Walker, 197 Vignon (Léo,, Osazones from Oxycelluloses, 24 Vigouroux (Emile), Action of Chlorine on Mixture of Silicon, Silica and Aluminium, 384 Vilmorin (H. L. de), Death of, 440 Virchow (Prof.), Death of Johannes Miiller, 595 Visit of the Institution of Electrical Engineers to Switzerland, Prof. Richard Threlfall, F.R.S , 578 Viticulture ; Late Watering of Vine, A. Miintz, 215% Physique et Chimie Viticoles, A. de Saporta, 364 Vivisection, the Ethics of, 329 Vivisection in 1898, Statistics of, 156 Volcanoes, their Structure and Significance, T. G. Bonney, F.R.S., 27; Early Tertiary Volcanoes of Absaroka Range, Arnold Hague, 112 Vole, James Dallas, 546 Voller (A.), Spectrum of Wehnelt Spark, 456 Volta Centenary Exhibition at Como, the, Prof. G. H. Bryan, BRS. or Waddell (John), the Arithmetic of Chemistry, 100 Waite (E. R.), the “‘ Palu” Fish, 536 Walden (A. F.), Condition of Dissolved Substances in Non- Aqueous Solutions, 259 Walker (James), Views on some of the Phenomena of Nature, 197 Wallich (Surgeon-Major G. C.), Obituary Notice of, 13 Walrus, Kumagusu Minakata, 150 Walter (B.), the Nature of Electric Sparks, 87; Spectrum of Wehnelt Spark, 456 Nature, ] December 14, 1899. Lndex Walters (1°. Rufenacht), Sanatoria for Consumptives in Various Parts of the World, 221 Wanklyn (J. Alfred), Sewerage Analysis, 172 Warning Colours in Butterflies, Illustrations of Mimicry and Common, Mark L. Sykes, 222 Warning Colours, Mimicry and, Edward B. Poulton, F.R.S., Prof. R. Meldola, F.R.S., 55 Ward (Prof. H. M., F.R.S.), a Horn-Destroying Fungus, 92 Ward (Prof. Marshall), Symbiotic Fermentation, 609 Warren (E.), Inheritance in Parthenogenesis, 142 Warships, Mechanical Engineering in, Sir Wm. H. White, K.G.B:, B.R.S:,20 Washington (H. S.), Italian Volcanic Rocks, 612 Washington Navy Yard, New Experimental Basin in, 374 Washington Star Catalogue, Second, 18 Water : the Microscopy of Drinking-Water, G. C. Whipple, 146; Examination of Water, W. P. Mason, 146 ; Preliminary Results of a Research on the Variation of the Specific Heat Water with Temperature, Prof. Callendar, 585 Waterhouse (General), the Sensitiveness of Polished Silver to Light, 539 Waterhouse (Colonel), on a Remarkable Result observed on the Exposure of Metallic Silver to Light, 609 Watson and Son’s (Messrs.) ‘‘ Kromaz” Colour Photographic Apparatus, 539 Watts (Prof. W. W.), on a Smoothed and Grooved Surface of Mount Sorrel Granite underlying Undisturbed Keuper Marl, 610 Wave or Billow Clouds, 235 Wave Theory of Light, the, its Influence on Modern Physics, Prof. A. Cornu, 292 Waves, Deep-Sea, V. Cornish, 586 Wearing away of Sand Beaches, the, W. H. Wheeler, 115 Weather, Sea Gulls and, Prince Kropotkin, 439 Weather, Movement of Sea-Gulls with a coming Change of, Lieut.-Colonel H. H. Godwin-Austen, F.R.S., 491; W. F. Sinclair, 545 Weathers (John), die Alpen Pflanzen in der Gartenkultur der Tieflander, Erich Wocke, 6; das Heidelberger Schloss und seine Garten in alter und neuer Zeit und der Schlossgarten zu Schwetzingen, H. R. Jung, W. Schroder, 52 Webb (Wilfred Mark), the Exhibition of Recent Acquisitions at the Natural History Museum, 12; the International Con- ference on Hybridisation and Cross-breeding, 305 Weber (R. H.), Resistance of Alloys, 540 Webster (H. Cayley), through New Guinea and Cannibal Countries, 49 Wehnelt (A.), Kathode Rays, 456; Experiments on Kathode Rays, 576 Wehnelt interrupter, Dr. J. Macintyre, $8; A. Voller and B. Walter, 456; Action of, H. T. Simon, 383 ; Experiments with, E. Lecher, 456 Weighing, Measurement and, E. Edser, 221 Weir (James), the Dawn of Reason, 100 Weismann (August), Thatsachen und Auslegungen in Bezug auf Regeneration, 242 Wells (W.), Essentials of Plane and Solid Geometry, 290 Wellman Polar Expedition, 426 ; Return of, 399 Welt als That, die, J. Reinke, 490 West Indian Bulletin, the, 371 West Indian Hurricane of August 3—September 12, 1899, the, 622 West Indies, Commercial Cuba, William J. Clark, 7 Weston (C. P.), Determination of Modulus of Elasticity for Copper, Brass and Steel under Small Loads, 485 Wharton (Rear-Admiral Sir W. J. L., K.C.B., F.R.S.), Under- currents, 316 Wheeler (W. H.), the Wearing away of Sand Beaches, 115; Tides in the Bay of Fundy, 461 Whipple (G. C.), the Microscopy of Drinking-Water, 146 ; Ostertonella Formosa, 624 White (Taylor), Asia, the Land of Rice, 8; the New Zealand Godwit (Zimosa Novae-Zelandiae), 29 White (Sir William, K.C.B., F.R.S.), Mechanical Engineering in Warships, 20; Opening Address in Section G of the British Association, Steam Navigation, 527 White Spot on Jupiter, Ph. Fauth, 161 Whiteaves (J. F.), the Devonian System of Canada, 515 Whitehead (C. S.), Electro-magnetic Theory, Vol. ii., 589 XXXV Whitehead (John), Death of, 204 Whiteley (M.A.), Study of Variability and Correlation of Hand, gI Whitmore (Dora), Pair of Brazilian Marmosets Breeding in England, 199 Whittaker (E. T.), Report on the Problem of Three Bod 584. Wiborgh (Prof. J.), the Use of Finely Divided Iron Ore, 402 Wiedemann (E.), Experiments on Kathode Rays, 576 Wiedemann’s Annalen, 117, 212, 383, 456, 540, 635 Wiener (O.), Observations of Fringes in Development of Daguerre Plates with Wedge-shaped Silver Iodide Layers, 8 Wiesbaden, the Scientific Conference at, 634 Wilczynski (Dr. E. J.), Dynamical Theory of Nebule, 281 Williams (H. S.), Palzeotrochis, 117 Wilson (C. T. R.), Comparative Efficiency as Condensation Nuclei of Positively and Negatively Charged Ions, 238 Wilson (Sir C. W.) K.C.B., F.R.S., Leitfaden der Kartenent- wurfslehre, Prof. Dr. Karl Zoppritz, 435 Wilson (H. A.), Electrical Conductivity of Flames containing Salt Vapours, 69 Wilson (Wm. H.), Habits of the Cuckoo, 175 Wind (Dr. C.), the Diffraction of Rontgen Rays, 300 Wine-making : Improvement of Wines by preliminary Heating of Must, A. Rosenstiehl, 24 Wireless Telegraphy, Prof. D. E. Hughes, 35 Wireless Telegraphy between Two Balloons, 278 Witchell (C. A.), Cries and Calls of Wild Birds, 171 Wocke (Erich), die Alpen Pflanzen in der Gartenkultur der Tieflander, 6 Wolff (J. E.), Age of Franklin White Limestone of Sussex County, New Jersey, 182 Women’s International Congress, Science at the, 228 Wood (Prof. R, W.), the Diffraction Process of Colour-Photo - graphy, 199; Dark Lightning, 460 Wood (Walter J.), Graduated Test Papers in Elementary Mathematics, 52 Woodhead (Prof. G. Sims), Is Insusceptibility to Vaccine Pro- duced by Small-pox, 436 Woodworth (J. B.), Glacial Wash-Plains of Southern New England, 258 Woodworth (Dr. R. S.), the Accuracy of Voluntary Movement, 549 Worthington (A. M.), Impact with a Liquid Surface studied by Instantaneous Photography, 93 Wortman’s (Dr. J. L.) Expedition to Wyoming for Dinosaurs, 577 Wrapson (James P.), Mathematical Tables, 590 Wyrouboff (G.), Constitution of Oxides of Rare Metals, 240 Year-Book of the United States Department of Agriculture, 1898, 315 Yeast, on the Combined Action of Diastase and, on Starch Granules, Dr. G. H. Morris, 608 Yerkes Object-glass, Temperature Changes in, Prof. Barnard, 281 Yorkshire, Extra-Morainic Drainage in, Prof. P. F. Kendall, 610 Yttrium, on Victorium, a New Element Associated with, Sir William Crookes, F.R.S., 317 Young (Prof. S.), Thermal Properties of Normal Pentane (Part IL.), 118 Young (T. E.), Centenarians and the Duration of the Human Race, 73 Younghusband (Major G. J.), the Philippines and Round About, 149 Zander, (Dr. E.), Abdominal Bristle-like Apparatus o Hy- menoptera, 432 Zeitschrift fiir Wissenschaftliche Zoologie, 117, 432 Zeleny (John), Rontgen Rays and Convection Currents, 86 Zenger (Ch. V.), Law Connecting Motion in Planetary System, 597 Zenneck (J.), Accurate Control of Frequency of Alternating Cur- rents, 384 XXXVI Index Zoology: Obituary Notice of Surgeon-Major G. C. Wallich, 13; Report of Zoological Society, 14; Additions to the Zoological Gardens, 17, 38, 63, 88, 114, 136, 160, 186, 207, 231, 260, 281, 301, 330, 354, 376, 402, 429, 442, 487, 513, 538, 550, 577, 597, 625; Phosphorescent Earth- worms, Frank E. Beddard, F.R.S., 52; Prof. W. Blaxland Benham, 591; the Development of the Tuatara, Prof. Wm. Blaxland Benham, 79; the Parietal Eye of New Zealand Tuatara, Dr. A. Dendy, 184; External Features in Development of Lefedosiren paradoxa, J. G. Kerr, 93; Zeitschrift fiir Wissenschaftliche Zoologie, 117, 432; the Springbuck ‘‘ Trek ” in Cape Colony, C. Schreiner, 135; in the Australian Bush, and on the Coast of the Coral Sea: being the Experiences and Observations of a Naturalist in Australia, New Guinea and the Moluccas, Richard Semon, 169; the Sea-Elephant, Rupert Vallentin, 190; Zoological Nature, December 14, 1899 Society, 190, 215; the Giant Tortoises of the Galapagos, W. Herbert Purvis, 199; Zoological Distribution of Tuber- culosis, Dr. W. Hutchinson, 215; the Geography of Mammals, W. L. and P. L. Sclater, 217 ; Cours Elémentaire de Zoologie, Remy Perrier, 364 ; a Curious Salamander, Dr. Charles Minor Blackford, 389 ; Sewellels, Dr. D. G. Elliott, 427 ; the Ground Sloth of Patagonia, Dr. R. Hauthal, 512; Batrachians of Paraguayan Chaco, J. S. Budgett, 513; the Squirrels, North Mexico, Dr. Allen, 537; Two New Mice, Barrett Hamilton, 549 ; Importance and Promise in Study of Domestic Animals, Prof. S. H. Gage, 562; the Skull of Hatteria, Prof. W. Blaxland Benham, 567 Zoppritz (Prof. Dr. Karl), Leitfaden der Kartenentwurfslehre, 435 Zwiers (I. J.), Return of Holmes’ Comet (1892 III.), 63; the System of Sirius, 429 ICHARD CLAY AND SONS, LIMITED, LONDON AND BUNGAY SUPPLEMENT TO NATURE, MAY 474 1899 77 A jet QU LVL PPIAO A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. “To the solid ground Of Nature trusts the mind which buzlds for aye.” —WORDSWORTH. THURSDAY, MAY 4, 1899. S CLE MEDLEL GC WOR TRIPLES. XXXII.—SIMON NEWCOMB. EWCOMB must be considered, without contradic- tion, as one of the most celebrated astronomers of our time, both on account of the immensity of his work and the unity of view which marks the choice of | the subjects treated by him. All is linked together in our solar system: the study of the motion of each one of the celestial bodies forming part of it is based upon the knowledge of a great | number of numerical data, and there exists no funda- | mental element whose influence is not repercussed on the entire theory of these bodies. To endeavour to build up the theory of our whole planetary world on an absolutely homogeneous basis of constants was an almost | superhuman task. The evaluation of each one of these data demands, indeed, that one should attentively go over most of the | previous researches, and continue them by more thorough methods. All Newcomb’s work, followed up with rare perseverance, has constantly tended to this ideal end: | the ingenious method suggested by Léon Foucault. first to arrive at a more exact knowledge of the magni- tudes serving as points of reference, and then to establish the theory, not only of all the planets, but also of their satellites on a system of constants as precise as modern observations permit. Wishing to realise in a complete manner this vast programme, Newcomb has recognised that the published observations do not always furnish the necessary information for obtaining with exactness all the looked-for elements. Abandoning, therefore, the domain of pure speculation, he has given himself up to researches which proclaim him possessed of a talent of observation of the highest order. By personal studies he has succeeded in filling many of the gaps which seriously impeded the progress of theory. Thus, in order to determine the masses of Neptune and Uranus and the elements of their satellites, he madea series of ob- servations of great value, on which are partially founded the ephemerides inserted in all nautical almanacs. NO. 1540, VOL. 60] I shall simply mention here in a few words some of the preparatory work preceding the construction of the magnificent edifice of which I have indicated the plan, on the happy completion of which the scientific world is to be congratulated. Throughout its execution one recognises the sign of a master-mind whose conclusions assume a definite character and remain acquired to science. The solar parallax is one of the most essential data which intervene in all researches concerning the planetary system. Newcomb undertook to fix its value by the dis- cussion of all the transits of Venus observed previously to 1882. In a very detailed memoir, he calls astro- nomers’ attention to the danger to which they are exposed by giving an exaggerated confidence to certain modern methods. The systematic exclusion of the ancient observations cannot sufficiently be justified by discordances which exist between their results and those obtained more recently. By a minute and impartial discussion of all existing documents, Newcomb arrived at a value almost identical with the one adopted in 1896 by the International Conference of Paris. Again, in order to obtain by an altogether independent means the value of this same constant, Newcomb under- took a determination of the velocity of light, based on These researches of a physical nature opened the way to an important advance in our knowledge of the heavens. In fact, we had all reason to hope that the value obtained for the velocity of light, combined with the constant of aberration, would allow us to determine the solar parallax more accurately than by the usual astro- nomical methods. Newcomb holds that multiplicity of methods is an essential condition of success ; this motive led him to choose Foucault’s methcd, which he applied with rare sagacity. The agreement between the different results obtained in this way by Cornu, Michelson and Newcomb is an admirable one, and testifies to the knowledge and skill of the experimenters. With the help of the values found for the velocity of light, it would have been possible to deduce the parallax, if recent observa- tions had not revealed the uncertainty which still hovers over the real value of the aberration constants. B 2 NAGOTRE [May 4, 1899 I cannot close the list of these preparatory studies without referring to a subject which interests the highest problems of astronomy of precision. The observations of the planets and of the moon depend on the coordinates of the fundamental stars, of which unfortunately we possess as yet no catalogue ab- solutely free from systematic errors. One of Newcomb’s constant preoccupations was to try to constitute a uni- form system of points of reference, at least in right ascension, this coordinate having we ghty importance in the case of observations of moving bodies. The cata- logues drawn up by him, and by Auwers, for the funda- mental and bright stars of the ecliptic, have shared in equal measure up to a very recent date the favour of astronomers. But the use, in the same scientific research, of elements derived from different sources, presents in- conveniences acknowledged for a long time. A reform in this direction had become very desirable. This cir- cumstance has again afforded Newcomb the opportunity of manifesting the inexhaustible resources of his activity and talent. An international conference, held in Paris in 1896, under the auspices of the Bureau des Longi- tudes, had as its object to elaborate a common system of constants and fundamental stars to be employed in the astronomical ephemerides. Newcomb took one of the most important parts in the discussions and resolutions of this conference. At its suggestion he has under- taken, not only the research of the definitive values to adopt for the lunar-solar precession and the planetary precession, but also the construction of a new catalogue of fundamental stars in accordance with the system of elements chosen by the Paris meeting of astronomers. Newcomb has consecrated these two later years to the accomplishing of this arduous task. The catalogue of fundamental stars, which he has just finished, will come into use in the beginning of Igor, and will realise in the work of astronomers that unity and simplification so long desired. I now come to the labours which have absorbed the greatest part of Newcomb’s scientific activity : they refer to the domain of celestial mechanics. At the time when the great work of Le Verrier had only reached the tables of Jupiter, Newcomb published an excellent theory of the two planets furthest from us, Uranus and Neptune. These tables, from the moment of their appearance, have been used by astronomers of every country. Among the greatest triumphs of Newcomb’s career must be counted his many and fruitful researches on the motion of the moon The theory of the moon bristles with difficulties. No one has yet succeeded in establish- ing a complete harmony between theory and observation. In his lunar tables, Hansen, in order to obtain this accordance for a limited interval of time, was obliged to attribute to an inequality arising from the action of Venus an empirical coefficient of an excessive amount, and to adopt besides an acceleration of the secular move- ment twice as great as that which results from the law of universal gravitation according to the calculations of two illustrious geometricians, Adams and Delaunay. Should we, as a great number of savan¢s think, attribute to Hansen’s number, so far from the theoretical value, an indisputable reality, and try to discover the physical NO. 1540, VOL. 60} causes of the anomaly ; or should we see the origin of the disagreement in an erroneous interpretation of his- torical documents? Newcomb did not recoil before the difficulties which the solution of this problem entailed. He discussed all the occultations observed since the invention of the telescope up to a recent time ; he him- self examined forgotten observations, buried for one. hundred and fifty years in the registers of the Paris Observatory. These neglected documents have thrown a vivid light on the question. In thus utilising an abun- dant harvest of new information, and correcting Hansen’s theory by the exclusion of every empirical coefficient, Newcomb arrived at results of fundamental importance. He proved, agreeing in this with Tisserand’s researches, that the eclipses of the Almagest, and those of the Arabs, as well as the ancient occultations, agree very well with the theoretical value of the secular acceleration ; and further, as a corollary, that the most ancient solar eclipses, the representation of which would seem to de- mand an increase of the secular acceleration, can without scruple be left out of consideration, either because the reality of the phenomenon remains doubtful, or because there exists too great an uncertainty in the hour and place of observation. One might withont inconvenience, therefore, adopt the theoretical acceleration of 6”, correcting the mean motion and the longitude of the epoch. But whatever value is chosen, and this was not anticipated, one must, after having suppressed Hansen’s erroneous inequality, resign oneself to introduce another notable empiric term of a- period of about two hundred and seventy years, and of an unexplained origin ; one simply notes that this ampli-. tude is nearly that of an inequality due to Venus, the existence of which is not doubtful. Besides this empiric inequality, Newcomb has dis- covered another, less. pronounced, with a coefficient superior to 1”, with an amplitude of about twenty-seven days, and appearing to be associated with a long period perturbation of the excentricity and perigee. These delicate deductions have since been confirmed by the theoretical researches of Messrs. Neison and Hill, which show that the terms in question are due to the action of Jupiter. By all these investigations, Newcomb has elucidated, in a masterly way, the actual state of the theory of the motion of our satellite. The two theories of the moon which must be con- sidered the best are those of the two celebrated geometricians, Delaunay and Hansen ; they are founded on totally different methods. By the help of a long, minute and tedious transformation, because it is a question of formule occupying several quarto volumes, Newcomb has rendered their expressions immediately comparable, bringing them moreover to a system of precise and uniform constants. Further, by this comparison, he has shown that, in spite of the difference of method, the two theories lead to identical results for solar perturbations, which form the essential part of them and are indeed the only ones which were calculated by Delaunay. I must now pass very briefly to some of Newcomb’s other memoirs. One of his most original researches is relative to Hyperion, Saturn’s seventh satellite, dis- covered almost simultaneously by Bond and Lassell. ee May 4, 1899] NATURE > o The movement observed was in disaccord with the pre- diction of theory. In fact the major axis of Hyperion’s orbit, instead of moving, directly, round Saturn in a century, accomplished a revolution in the opposite direc- tion in the short period of eighteen years. Newcomb has proved that this rapid retrograde revo- ution is caused by the perturbing action of the next satellite Titan. - In the various volumes of “ The Astronomical Papers for the use of the American Nautical Almanac,” New- 2menorhinus rhombeatus), two Crossed Snakes (Psammophis crucifer) from South Africa, presented by Mr. J. E. Matcham; a Common Snake (Zyopzdonotus natrix), British, presented by Mr. E. C. Brook ; two Common Marmosets (Hafale jacchus) from South- east Brazil, a Reticulated Python (Python reticulatus) from the | East Indies, a Spiny-tailed Iguana (Ctexosaura acanthura) from ‘Central America, a South Albemarle Tortoise (Zestado vicina) | from the Galapagos Islands, deposited ; (Lemur coronatus), born in the Gardens. NO. 1542, VOL. 60] MATORE two Crowned Lemurs | OUR ASTRONOMICAL COLUMN. PARTIAL ECLIPSE OF THE SUN, JUNE 7.—This eclipse will be visible at Greenwich and throughout Northern Europe and Northern Asia. The Greatest Eclipse will be visible in latitude 67° 18’ N., and longitude 99° 5’ W. of Greenwich, on June 7d. 18h. 34" om. ; the magnitude being 0611 (sun’s diameter = 1). The following table gives the details for British stations, Green- wich mean time being used in all cases except that of Dublin, where local mean time is taken. Station | Begins Gsine Ends Mise, h. m. h. m. h. m. Greenwich ... 16 42'8 17 17°4 17 53°4 o'188 Cambridge ... 16 43°2 17 186 | 17 55°5 O°197 Oxford... 16 42°8 D7 LSs20 s\n) SS 0°200 Liverpool ... 16 43°8 17, 20-5) || 18: (O:Olo2Rg Edinburgh ... 16 45°7 17 25°9 18 7°8 0'263 Dublin... 16 18°6 16 57°3 17 37°6 | 0°253 | = At Greenwich and approximately throughout the British Isles the contacts are as follows :— Angle from f First contact 42° towards the eS Fo North Point | Last ,, BOE. 3 fat Bast di ¥ Angle from f First ,, Gero 5» West (7/726 Vertexg alle lcastamurctmn One) 5s i, Bast) (Sse: Comer 1898 a (Swirt).—The following ephemeris is by Herr H. Kreutz, in Astr. Mach., No. 3556 :— ae Fe) jet 12h. Berlin Mean Time. 1899- = Decl. Br. as Ss. May 18 ... 22 34 21 +43 42°9 19 .. 23 37 45 23°71 1°77 20) Fs 22a O a7 MAL) 21 . 21 58 20 48 44°5 1°79 22 43 29 50 22°7 23 26 59 51 56°5 179 24 eno 53 23°9 25 les 20145, 31 +54 41°8 7, During the ‘enh the comet passes through ieee without being near any conspicuous stars. Onthe 21st it enters Cygnus, being about 10° north-east of a Cygni on the 24th. TEMPEL’s CoMET (1873 II.).—M. L. Schulhof gives the following ephemeris for. this comet in Ast. Nach., No. 3554):— Ephemerts yah 12k. Parts Mean Time. R.A. 1899. Decl. Br. m, ‘s. Ch yee /3 May 18 ... 19 T2eLO3t —- 355 17 TOM 13) 5320) -. BrSe is 9). oe S.A Yf he 3 51 28... 0°764 21 Ge MORO born 3.49 55 22 18 41°8 ... 3 48 38 23 20 17'3 ..- 3 47 3 24s ZTE 5253... 3 46 53... 0869 25 . 19 23 27°0... — 3 46 2 The comet is moving slowly in a north-easterly direction through the constellation Aquila. RETURN OF HOLMEs’ COMET (1892, III.).—The following ephemeris is by Mr. H. J. Zwiers in Astr, Nach., No. 3553- Ephemerts erat uae Greenwich Mean Time. 1899. : Decl. Br. hs mes. Sa May 18 © 34 532 ... + 10 12 50 00208 ZO Ree 38 22°5 10 50 0 ‘0301 22 41 511 Li 2706S “0304. 2 45 19°! 12) 4y13 0306 26 48 46°2 12 41 15 0309 28 2p Tait 13 18 14 0312 39 5) SURG. some tes “0315 June I 059 44 . + 14 31 58 0318 No information as to any observations of this comet has yet | been received. The positions given above would indicate it to be moving to the north-east through Pisces ; at the end of the | month it will be about half-way between Vy Pegasi and B Arietis, but after this it will probably be lost owing to its nearing the ( sun, 64 NATURE ROTATION PERIop OF Mars.—Mr. W. F. Denning has recently secured some measures of the times of transit of the Syrtis Major (Kayser Sea), which in conjunction with observ- ations made by him in 1884 and 1869 give a critical value for the period (Odservatory, May 1899, p. 195). On February 4, 1869, the Syrtis Major was in mid-transit at 11h., while on February 14, 1884, when Mars was similarly situated with reference to the Earth, the transit occurred at 5h. 55m. Other transits were taken as February 15, 6h. 35m. ; February 19, gh. 5m.; February 22, 11h. 4m. Now, after another interval of fifteen years, the transit on March 7, 1899, occurred at 8h. 31m. The whole period between 1869 February 4, Ith. and 1899 March 7, 8h. 31m., comprises 10,987 days, 21 hours, 31 minutes, during which Mars has performed 10,710 rotations. The mean period during this interval thus becomes 24h. 37m. 22°70s. This value is intermediate between those of Proctor and Bakhuyzen. AN IMPROVED RESISTANCE-BOX. MESSRS. GAMBRELL BROS. have recently introduced a resistance-box of improved design, which gives promise of eliminating several of the disadvantages of the usual post- office pattern. Fig. 1 shows the appearance of the box with the cover removed to show the working parts. The coils, which hang vertically in the lower part of the box, are brought up to Fic. 1.—General view of the box, from above, showing the numbered slide rods, the contact shoes and the terminal studs of the coils. The handle (H) at the right is for clamping all the contact shoes simultaneously. terminal studs (T) seen in Fig. 2, arranged in five rows, one of which, in two sections, forms the ‘‘ ratios” used as two arms of the bridge. The upper surfaces of these studs are semi- circular, fitting the concave surfaces of the sliding contact shoes (s). The four rows other than the ‘‘ ratios” provided for thou- sands, hundreds, tens and units, reckoned from the side nearest the terminals and key. Each of these contact shoes slides with slight friction on a brass bar running the length of the box, and supported at each end by metal pillars held down by springs in- side the box. To move the shoes from one stud to another other Fic. 2.—Showing construction of slider, spring contact bar, &c. brass rods are attached, which slide through ebonite bushes on the end of the box. On these rods are engraved the figures giving the amount of resistance in use, the value of any par- ticular resistance in circuit being indicated by the number show- ing just outside the ebonite bush. To ensure the contact shoe being properly fixed on the studs, a spring detent (p, Fig. 2) is provided under each bar, so that the resistances may be changed without the experimenter needing to watch the bar. All the bars being arranged to give the resistance required, it will be evident that its total amount can be read straight off at the end NO. 1542, VOL. 60] [May 18, 1899 of the box, being given by the row of figures close to the four ebonite bushes. For example, the reading of the resistance in circuit, as shown in Fig. 1, is 2310. This is itself a great con- venience, and will prevent any chance error in adding. Asan additional help to maintaining the contacts as constant and perfect as possible, when the proper resistance has been found, all the four shoes are drawn tightly down on to the terminal studs by turning the handle H, seen under the ends of the rods in Fig. 1. This actuates a cam inside, which moves the small pillars at each end of the brass bars passing through the contact shoes. At the same time, the arrangement acts as a clamp, so that while the handle is turned the resistances cannot be changed, All the pillars are held down by springs, so that when not clamped by the handle H the sliding to and fro is accompanied by sufficient friction to keep the contact surfaces clean. In consequence of the ingenious method adopted for reading off the figures, rendering access to the contacts themselves quite unnecessary, the whole of the system of studs and sliding bars is covered in permanently, so that they and the ebonite insulating block are kept free from dust and corrosion. The studs, being a considerable distance apart, should permit of a very high in- sulation resistance, while at the same time allowing a large surface contact between the shoe and the stud. It will be seen that this new form of box has many advantages to recommend it to notice. The simplicity and rapidity of read- ing, its compactness, and its non-liability to deterioration, should cause it to find favour both in laboratory and testing-room experience. TRANSPARENCY AND OPACITY} ONE kind of opacity is due to absorption ; but the lecture dealt rather with that deficiency of transparency which depends upon irregular reflections and refractions. One of the best examples is that met with in Christiansen’s experiment. Powdered glass, all from one piece and free from dirt, is placed in a bottle with parallel flat sides. In this state it is quite opaque ; but if the interstices between the fragments are filled up with a liquid mixture of bisulphide of carbon and benzole, carefully adjusted so as to be of equal refractivity with the glass, the mass becomes optically homogeneous, and_ therefore transparent. In consequence, however, of the different dis- persive powers of the two substances, the adjustment is good for one part only of the spectrum, other parts being scattered in transmission much as if no liquid were employed, though, of course, in a less degree. The consequence is that a small source of light, backed preferably by a dark ground, is seen in its natural outlines but strongly coloured. The colour depends upon the precise composition of the liquid, and further varies with the temperature, a few degrees of warmth sufficing to cause a transition from red through yellow to green. The lecturer had long been aware that the light regularly transmitted through a stratum from 15 to 20 mm. thick was of a high degree of purity, but it was only recently that he found to his astonishment, as the result of a more particular observation, that the range of refrangibility included was but two and a half times that embraced by the two D-lines. The poverty of general effect, when the darkness of the background is not attended to, was thus explained, for the highly monochromatic and accord- ingly attenuated light from the special source is then overlaid by diffused light of other colours. More precise determinations of the range of light transmitted were subsequently effected with thinner strata of glass powder contained in cells formed of parallel glass. The cell may be placed between the prisms of the spectroscope and the object- glass of the collimator. With the above-mentioned liquids a stratum 5 mm. thick transmitted, without appreciable disturb- ance, a range of the spectrum measured by 11°3 times the interval of the D’s. In another cell of the same thickness an effort was made to reduce the difference of dispersive powers. To this end the powder was of plate glass and the liquid oil of cedar-wood adjusted with a little bisulphide of carbon. The general transparency of this cell was the highest yet observed. When it was tested upon the spectrum, the range of refrangibility transmitted was estimated at thirty-four times the interval of the D’s. As regards the substitution of other transparent solid materia) 1 A discourse delivered at the Royal Institution on Friday, Mareh 24, by the Right Hon. Lord Rayleigh, F.R.S. May 18, 1899] NATURE 65 for glass, the choice is restricted by the presumed necessity of avoiding appreciable double refraction. Common salt is singly refracting, but attempts to use it were not successful. Opaque patches always interfered. With the idea that these might be due to included mother liquor, the salt was heated to incipient redness, but with little advantage. Transparent rock-salt artificially broken may, however, be used with good effect, but there is some difficulty in preventing the approximately rect- angular fragments from arranging themselves too closely. The principle of evanescent refraction may also be applied to the spectroscope. Some twenty years ago an instrument had been constructed upon this plan. Twelve 90° prisms of Chance’s ‘‘dense flint” were cemented ina row upon a strip of glass (Fig. 1), and the whole was immersed in a liquid mix- ture of bisulphide of carbon with a little benzole. The dis- persive power of the liquid exceeds that of the solid, and the difference amounts to about three-quarters of the dispersive power of Chance’s ‘‘extra dense flint.” The resolving power of the latter glass is measured by the number of centimetres of available thickness, if we take the power required to resolve the D-lines as unity. The compound spectroscope had an available thickness of 12 inches or 30 cm., so that its theoretical resolving power (in the yellow region of the spectrum) would be about 22. With the aid of a reflector the prism could be used twice over, and then the resolving power is doubled. One of the objections to a spectroscope depending upon bi- sulphide of carbon is the sensitiveness to temperature. In the ordinary arrangement of prisms the refracting edges are vertical. | If, as often happens, the upper part of a fluid prism is warmer than the lower, the definition is ruined, one degree (Centigrade) of temperature making nine times as great a difference of refrac- tion as a passage from D, to D,. The objection is to a great extent obviated by so mounting the compound prism that the refracting edges are horizontal, which of course entails a | encountering a large number. and liquid that would more nearly assimilate the two cases. If, for example, the glass consisted of equal spheres resting against one another in cubic order, some rays might pass entirely through glass and others entirely through liquid, and then the quarter wave-length of relative retardation would enter at the same total thickness in both cases. But such an arrangement would be highly unstable ; and, if the spheres be packed in close order, the extreme relative retardation would be much less. The latter arrangement, for which exact results could readily be calculated, represents the glass powder more nearly than does the cubic order. A simplified problem, in which the element of chance is retained, may be constructed by supposing the particles of glass replaced by thin parallel discs which are distributed entirely at random over a certain stratum. We may go further and imagine the discs limited to a particular plane. Each disc is supposed to exercise a minute retarding influence on the light which traverses it, and they are supposed to be so numerous that it is improbable that a ray can pass the plane without A certain number (vz) of encounters is more probable than any other, but if every ray encountered the same number of discs, the retardation would be uniform and lead to no disturbance. It is a question of probabilities to determine the chance of a prescribed number of encounters, or of a prescribed deviation from the mean. In the notation of the integral calculus the chance of the deviation from mm lying between + 7 is (see Phd. Mag., 1899, vol. xlvii. p. 251) 2 ie -a cee GES oho. NJ o where t=7//(2). This is equal to 84 when t=1'0, or r= ./(2m); so that the chance is comparatively small of a deviation from 7 exceeding + ,/(2 72). To represent the glass powder occupying a ie | stratum of 2cm, thick, we may perhaps suppose Fic. 1. horizontal slit. The disturbance due to a stratified temperature is then largely compensated by a change of focus. In the instrument above described the dispersive power is great—the D.-lines are seen widely separated with the naked eye —but the aperture is inconveniently small (4-inch). In the new instrument exhibited, the prisms (supplied by Messrs. Watson) are larger, so that a line of ten prisms occupies 20 inches. Thus, while the resolving power is much greater, the dispersion is less than before. In the course of the lecture the instrument was applied to show the duplicity of the reversed soda lines. The interval on the screen between the centres of the dark lines was about half an inch. It is instructive to compare the action of the glass powder with that of the spectroscope. In the latter the disposition of the prisms is regular, and in passing from one edge of the beam to the other there is complete substitution of liquid for glass over the whole length. For one kind of light there is no relative retardation ; and the resolving power depends upon the question of what change of wave-length is required in order that its relative retardation may be altered from zero to the quarter wave- length. All kinds of light for which the relative retardation is less than this remain mixed. In the case of the powder we have similar questions to consider. medium is optically homogeneous, 2z.e. the retardation is the same along all rays. If we now suppose the quality of the light slightly varied, the retardation is no longer precisely the same along all rays; but if the variation from the mean falls short of the quarter wave-length it is without importance, and the medium still behaves practically as if it were homogeneous. The difference between the action of the powder and that of the regular prisms in the spectroscope depends upon this, that in the latter there is complete substitution of glass for liquid along the extreme rays, while in the former the paths of all the rays lie partly through glass and partly through liquid in nearly the same proportions. rays is thus a question of a deviation from an average. For one kind of light the | The difference of retardations along various | that #2 = 72. There would thus be a moderate chance of a difference of retardations equal to, say, one-fifth of the extreme difference corre- sponding to a substitution of glass for liquid throughout the whole thickness. The range of wave-lengths in the light regularly transmitted by the powder would thus be about five times the range of wave- lengths still unseparated in a spectroscope of equal (2 cm.) thickness. Of course, no calculation of this kind can give more than a rough idea of the action of the powder, whose disposition, theugh partly a matter of chance, is also influenced by mechanical considerations ; but it appears, at any rate, that the character of the light regularly transmitted by the powder is such as may reasonably be explained. As regards the size of the grains of glass, it will be seen that as great or a greater degree of purity may be obtained in a given thickness from coarse grains as from fine ones, but the light not regularly transmitted is dispersed through smaller angles. Here again the comparison with the regularly disposed prisms of an actual spectroscope is useful. At the close of the lecture the failure of transparency which arises from the presence of particles small compared to the wave-length of light was discussed. The tints of the setting sun were illustrated by passing the light from the electric lamp through a liquid in which a precipitate of sulphur was slowly forming (of. cét., 1881, vol. xii. p. 96). The lecturer gave reasons for his opinion that the blue of the sky is not wholly, or even principally, due to particles of foreign matter. The molecules of air themselves are competent to disperse a light not greatly inferior in brightness to that which we receive from the sky. UNIVERSITY AND EDUCATIONAL INTELLIGENCE. OXx¥FORD,—The honorary degree of M.A. was conferred in Convocation on Tuesday upon Mr. Roland Trimen, F.R.S. Convocation has passed the decree accepting the offer of the Royal Geographical Society of 400/. for five years for the furtherance of geographical studies in Oxford, and providing an equal contribution from the funds of the University. CAMBRIDGE.—The following is the speech delivered on It is true that we may imagine a relative distribution of glass | May 11 by the Public Orator, Dr. Sandys, of St. John’s NO. 1542, VOL. 60] 66 NATURE [May 18, 1899 College, in presenting Prof. Kowalevsky, of St. Petersburg, for the honorary degree of Doctor in Science :— Russorum ab imperio maximo legatus ad nos subito advectus est vir illustris, qui investigandi rationes novas inter primos secutus, animantium formas quasdam inferiores ex alia in aliam paullatim mutatas identidem indagavit; qui in confinio inter genera vertebris instructa et vertebris carentia iampridem moratus, Amphioxi speciem ambiguam primus explicavit ; qui larvae denique Ascidianae cum vertebrato animalium genere affinitatem imprimis indicavit. Atqui, ne talium quidem virorum praeceptis attonitus, larvae illius degeneris propin- quitatem reformidabit homo non terrestris tantum sed etiam caelestis originis conscius, qui angelis paullo minor, gloria et honore est coronatus, super oves et boves, super feras omnes, super volucres et pisces, super omnia quae maris per vias pererrant, a Deo constitutus. Duco ad vos Zoologiae Professorem Petropolitanum, ALEX- ANDRUM KOWALEVSKY. The General Board have issued a report recommending that the stipends of the Reader in Botany (Mr. F. Darwin), the Lecturer in Organic Chemistry (Mr. Ruhemann), the Lecturer in Experimental Psychology (Dr. Rivers), and the Curator in Zoology (Mr. D. Sharp), should be increased; and that new Lectureships in Paleozoology and in Physical Anthropology should be established. A University Lectureship in Applied Mathematics will be vacant at Michaelmas by the resignation of Mr. Love, now Sedleian Professor at Oxford. Candidates are to send their names to the Vice-Chancellor by May 30. The stipend is 50/. a year. The new Professorship of Agriculture, with a stipend of 800/. a year contributed by the Drapers’ Company, was established by grace of the Senate on May It. THE Board of Education Bill was read for a third time, and passed, in the House of Lords on Monday. THE foundation-stone of a new school and technical insti- tute, connected with the Sir John Cass Foundation, in Jewry Street, Aldgate, was laid on Thursday last by the Bishop of London. The plans of Mr. A. W. Cooksey have been accepted for the new buildings, which will be in English Renaissance style, and will cost 45,000/. Mr. ANDREW CARNEGIE has written to the Right Hon. Joseph Chamberlain with reference to the proposed establish- ment of a University at Birmingham. and the correspondence is published in the Bzrmingham Dazely Post. Mr. Carnegie refers in the correspondence to the great advantage which the iron and steel industries of the United States have derived from the Cornell University, and goes on to remark that ‘‘if Bir- mingham were to take that University as its model, where the scientific has won first place in the number of students, and give degrees in science as in classics, I should be delighted to contribute the last 50,000/. of the sum you have set out to raise to establish the scientific department.” In addition to this Mr. Chamberlain, writing to the Lord Mayor of Birmingham, announces that an anonymous friend who had _ previously promised 25,000/. has agreed to increase his offer to 37,500/. on condition that the full amount of 250,000/. required for the minimum endowment is obtained. There still remains 12,000/, to be raised before the quarter of a million required is reached. AY the annual celebration of Presentation Day of London University, held on May 10, the Earl of Kimberley presided for the first time as Chancellor. Referring to the Act passed last year, the Chancellor remarked that under the provisions of that Act and under the statutes made, the examination part of the University, by which the University had hitherto been known and in which it had done most excellent work, would be duly preserved. What was to be added was very important indeed, and it would become, he hoped, a great teaching Uni- versity. They were at last beginning to appreciate the great changes which had taken place in the world, and in the advance- ment of science especially. Those changes had required others in the framing of the highest education. Not that they should for one moment abandon the old system of laying a good broad foundation of education, but that they should add to it the greater cultivation of the sciences, of economic science, and of all those arts which had grown to be of such great importance to this country.. What they wanted was to bring together, as NO. 1542, VOL. 60] far as possible, all those various agencies provided for higher education in the metropolis. INQUIRIES as to the schools in which leading men in various professions were educated have been made by Zhe School World, and the results for men of science are published in the current number. Of 250 representative men of science—mostly Fellows of the Royal Society—chosen for the present inquiry, one-fifth re- ceived their early education either in private schools or at home under tutors. The schools which claim the greatest number of old pupils in the selected list are Edinburgh High School, Edin- burgh Academy, and Aberdeen Grammar School. The Scotch schools are followed, as regards the number of old pupils of distinguished eminence in science, by the City of London School and King’s College School. Eton, Harrow, and Rugby succeed these, and are in turn followed by Liverpool College, Royal Institution School (Liverpool), and St. Paul’s. The remarkable point brought out by this comparison is the small part the great public schools have taken in training the leaders in science of the present day. When the men who are now in the foremost rank among philosophers were receiving their early education science was almost, if not quite, omitted from the public school curriculum, with the result that comparatively few boys from such schools have become eminent in the scientific world. The neglect of science in comparison with other subjects is shown by the fact that Eton, Harrow, Rugby, Winchester, Westminster, and one or two other public schools, though com- paratively poor in their scientific record, are shown by Zhe School World to have furnished the greatest number of leading men in Parliament, the Church, and the Law, Eton leading the way as regards numbers in each of these classes. THE proposal to utilise the buildings of the Imperial Institute for the purposes of the new London University was referred to in the report read at the annual meeting of the Fellows of the Institute on Monday. Lord James of Hereford, who has suc- ceeded the late Lord Herschell as chairman of the governing body, in moving the adoption of the report remarked thata new lease of life had been brought within the purview of the Insti- tute. Those responsible for its management had been ap- proached by the Government, who had to find accommodation for the London University. In the Institute they possessed a very great area of accommodation not needed by them, which could be devoted with very little adaptation for the purposes of the University. In the first place, to bring a great seat of learning under the roof of the Institute seemed to the governing body to be in accordance with the objects for which the Insti- tute came into existence. But it was only right that he should tell them that in affording this accommodation to the London University they were receiving from the Government a very substantial return. He was not in the position to enter into any details, because all the arrangements had not yet been com- pleted, but he might say that the negotiations were proceeding, and that by the financial return for the provision of the neces- sary accommodation for the University the governors of the In- stitute would be relieved of many burdens. The real result would be that they would have all anxiety removed with regard to the future conduct of the Institute. SCIENTIFIC SERIALS. Meteorologische Zeitschrift, February.—Results of the inter- national balloon ascent, by Dr. H. Hergesell. This is the first of a proposed series of papers ; the present one deals principally with the range of temperature, as shown by observations made in a captive balloon at Strassburg on June 7 and 8, 1898. The results prove that in strata of free air, whose height exceeds a few hundred metres, the temperature possesses an extremely small diurnal range. During the night it scarcely amounts to a few tenths of a degree ; while in the daytime a variation of some three or four degrees Centigrade may occur, even at a height of 800 metres, when vertical air currents exist. In the absence of these, the range would, in all probability, sink to a very low value.—On the characteristics of mild winters, by Dr. G. Hellmann. The last two mild winters have induced the author to revise his previous researches upon this subject, and he gives particulars of the 51 mild winters experienced in Berlin during the last 180 years. The principal results arrived at are: that mild winters scarcely ever occur singly, but in groups of two or three; that they are usually of long duration, from November to February or March ; severe and long, late winters (February and March) seldom occur after mild mid- May 18, 1899] NATURE 67 winters ; in’ mild mid-winters the greatest variations of temper- ature usually occur in January. After a very mild winter, a warm summer is more probable than after a winter which is only moderately mild. Dr. Hellmann pleads for synoptic charts for the whole globe—at least for short intervals, if longer periods cannot be undertaken. ; In the Journal of Botany for April and May, Mr. A. Lister describes and figures some new or interesting species of Mycet- ozoa; Mr. E. A. N. Arber discusses the relationship to one another of the various forms of indefinite inflorescence ; Mr. A. Gepp records the detection in Britain of a genus of Sapro- legneous fungi, Apedachlya ; Mr. G. S. West continues his ac- count of the alga-flora of Cambridgeshire ; Mr. F. S. Williams, his critical notes on species of Cerxastzum ; and Mr. H. C. Hart, his account of a botanical excursion in Donegal. SOCIETIES AND ACADEMIES. Lonpon. Royal Society, March 16.—‘‘ Experiments in Micro-metal- lurgy :—Effects of Strain. Preliminary Notice.” By Prof. Ewing, F.R.S., and Walter Rosenhain, 1851 Exhibition Research Scholar, Melbourne University. _ Much information has been obtained regarding the structure of metals by the methods of microscopic examination initiated by Sorby and successfully pursued by Andrews, Arnold, Charpy, Martens, Osmond, Roberts-Austen, Stead, and others. When a highly polished surface of metal is lightly etched and examined under the microscope, it reveals a structure which shows that the metal is made up in general of irregularly shaped grains with well-defined bounding surfaces. The exposed face of each grain has been found to consist of a multitude of crystal facets with a definite orientation. Seen under oblique illumination, these facets exhibit themselves by reflecting the light in a uniform manner over each single grain, but in very various manners over different grains, and, by changing the angle of incidence of the light, one or another grain is made to flash out comparatively brightly over its whole exposed surface, while others become dark. The grains appear to be produced by crystallisation proceed- ing, more or less simultaneously, from as many centres or nuclei as there are grains, and the irregular more or less polygonal boundaries which are seen on a polished and etched surface result from the meeting of these crystal growths. The grains are, in fact, crystals, except that each of their bounding surfaces is casually determined by the meeting of one growth with another. f The experiments, of which this is a preliminary account, have been directed ‘to examine the behaviour of the crystalline grains when the metal is subjected to strain. For this purpose we have watched a polished surface under the microscope while the metal was gradually extended until it broke. By arranging a small straining machine on the stage of the microscope, we have been able to keep under continuous observation a particular group of crystalline grains while the piece was being stretched, and have obtained series of photo- graphs showing the same group at various stages in the process. Strips of annealed sheet iron, sheet copper, and other metals have been examined in this way. We have also observed the effects of strain on the polished surfaces of bars in a 50-ton testing machine by means of a microscope hung from the bar itself, and have further observed the effects of compression and of torsion. . ’ When a piece of iron or other metal exhibiting the usual granular structure is stretched beyond its elastic limit, a remark- able change occurs in the appearance of the polished and etched ; surface, as seen by the usual method of ‘* vertical” illumination. A number of sharp ‘black lines appear on the faces of the crystalline grains: at first they appear on a few grains only, and as the straining is continued they appear on more and more grains On each grain they are more or less straight and parallel, but their directions are different on different grains. At first, just as the yield-point of the material is passed, the few lines which can be seen are for the most part transverse to the direction of the pull. As the stretch becomes greater oblique systems of lines on other grains come into view. The photograph, Fig. 1, taken from a strip of transformer plate (rolled from Swedish iron and annealed after rolling), gives a characteristic view of these lines as they appear after a moderate amount of permanent stretching, but long before the iron has reached its breaking limit. NO. 1542, VOL. 60] The appearance of each grain is so like that of a crevassed glacier, that these dark lines might readily be taken for cracks, The real character of the lines is apparent when the crystal- line constitution of each grain is considered.. They are not cracks, but s/¢ps along planes of cleavage or gliding planes. ; Fig. 2 is intended to represent a section through the upper part of two contiguous surface grains, having cleavage or gliding planes as indicated by the cross-hatching, AB being a portion of the polished surface. When the metal is pulled beyond its elastic limit, in the direction of the line a B, yielding takes place Fic. 1.—Soft sheet iron strained by tension. 400 diameters. by finite amounts of slips occurring at a limited number of places in the manner shown at a, 4, c, d, e (Fig. 3). This slip exposes short portions of inclined surfaces, and when viewed under normally incident light, these surfaces appear black be- cause they return no light to the microscope. They are con- sequently seen as dark lines or narrow bands, extending over the polished surface in directions which depend on the inter- section of the polished surface with the surfaces of slip. We have proved the correctness of this view by examining these bands under oblique light.. When the light is incident at Fig.2. Before straining. only a small angle to the polished surface, the surface appears for the most part dark; but here and there a system of the parallel bands shines out brilliantly in consequence of the short cleavage or gliding surfaces which constitute the bands having the proper inclination for reflecting the light into the microscope. Rotation of the stage to which the strained specimen is fixed makes the bands on one or another of the grains flash out successively, with kaleidoscopic effect. In what follows we shall speak of these lines as slip-bands. Fig. 1, through a mixed illumination, shows some of the slip-bands bright and some dark. Fig.3. After straining, When the metal is much strained a second system of bands appears on some of the grains, crossing the first system at an angle, and in some cases showing little steps where the lines cross. These bands are clearly due to slips occurring in a second set of cleavage or gliding surfaces. Occasionally a third system of bands may be seen. When the experiment is made with a polished but unetched specimen the slip-bands appear equally well. The boundaries of the grains are invisible before straining; but they can be distinguished as the strain proceeds, for the slip-bands form a cross-hatching which serves to mark out the surface of each grain. 68 NATURE [May 18, 1899 Fig. 4 is another sample of iron strained by pull. The specimen in this case was a bar of Swedish iron, in which a comparatively large crystalline structure had been developed by annealing for some hours at 700° C. The photograph was taken after the bar had been broken in the testing machine, and shows with a magnification of 400 diameters a portion of the surface not far from the place of fracture, The slip-bands are developed by compression as well as by extension. The bands developed by compression have appar- ently all the characteristics which they present in stretched pieces, and we could not, by microscopic examination of the surface, distinguish in this respect between the effects of com- pression and extension. By twisting an iron bar well beyond the elastic limit the slip- bands are made to appear, for the most part, in directions parallel and perpendicular to the axis of twist. A strip of sheet metal, such as iron or copper, in the soft state, when bent and unbent in the fingers, shows them well developed by the extension and compression of the surface. These experiments throw what appears to us to be new light | on the character of plastic strain in metals and other irregular | crystalline aggregates. Plasticity is due to slip on the part of the crystals along cleavage or gliding surfaces. Each crystalline grain is deformed by numerous internal slips occurring at intervals throughout its mass. In general these slips no doubt occur in three planes, or possibly more, and the combination of the three allows the grain to accommodate itself to its envelope of neighbouring grains as the strain proceeds. The action is discontinuous : it is. not a homogeneous shear but a series of finite slips, the portion of the crystal between one slip and the next behaving like a rigid solid. The process of slipping is one which takes time, and in this respect the aggregate effect is not easily dis- tinguishable from the deformation of a viscous liquid. We infer from the experiments that ‘‘ flow” or non-elastic deformation in metals occurs through slip within each crystalline grain of portions of the crystal on one another along surfaces of cleavage or gliding surfaces. There is no need to suppose the portions which slip to be other than perfectly elastic. The slip, Fic. 4.—Swedish iron, much strained. We have developed the slip-bands in iron, steel, copper, silver, gold, nickel, bismuth, tin, gun-metal, and brass. In gold.and silver they show particularly well, the crystalline struc- ture tbeing large and the lines straight. In copper also the lines are straighter and more regularly spaced than is general in iron. Most of these metals have been tested in the form of blocks under compression. A beautiful development of slip- bands may readily be produced by pinching a button of polished silver or copper in a vice, or by bending a strip of sheet metal. In carbon steels we have found the slip-bands considerably more difficult to observe than in wrought iron. The smaller granular structure of steel apparently makes the slip-bands correspondingly minute. In mild steel they are seen readily enough, but in a rather high carbon steel we succeeded in seeing them only with difficulty in the ‘‘ferrite” areas under a magni- fication of 1000 diameters. A cast piece of the nearly pure iron used for dynamo magnets showed a relatively very large granular structure and well marked slip-bands. NO. 1542, VOL. 60] 400 diameters. when it occurs, involves the expenditure of work in an irre- versible manner. It is because the metal is an aggregate of irregular crystals that it is plastic as a whole, and is able to be deformed in any manner as a result of the slips occurring in individual crystals. Plasticity requires that each portion should be able to change its shape and its position. Each crystalline grain changes its shape through slips occurring within itself, and its position through slips occurring in other grains.! The experiments were made in the engineering laboratory at Cambridge, and are being continued. The authors express their indebtedness to Sir W. Roberts-Austen and Mr. T. Andrews for advice as to the preparation of specimens of metals for microscopic examination. 1 Attention should be called in this connection to the experiments of Messrs. McConnel and Kidd on the plasticity of glacier ice (Ray. Soc. Proc., vol. xliv. p. 331). They found that bars cut from glacier ice which is an aggregate of irregular crystals are plastic. May 18, 1899] NATURE 6a April 27.—‘*On the Luminosity of the Rare Earths when heated in vacuo by means of Kathode Rays.” By A. A. Campbell Swinton. Communicated to the Royal Society by Lord Kelvin, F.R.S. For incandescent gas mantles it is found that certain definite mixtures of the rare earths are necessary in order to obtain the maximum luminosity. For instance, a mantle consisting of pure thoria or pure ceria will in the Bunsen flame only give about one-eleventh of the light of one composed of 99 per cent of thoria and 1 per cent of ceria, which is the mixture used by the Welsbach Company. In order to explain this remarkable fact, several contradictory theories have been propounded, and with a view to elucidating matters the author has made experiments in which mantles composed of different pure oxides and mixtures were heated by kathode ray bombardment in vacuo. The mantles were prepared according to the ordinary Welsbach process, and in order to obtain accurate comparisons the mantles were made in patchwork, each complete mantle being made up of two or four sections separately impregnated with different solutions. The mantles were so mounted in the vacuum tube that the kathode rays impinged equally upon the portions that consisted of different oxides and mixtures, so that an equal amount of energy was imparted to each sample. Under these conditions the Welsbach mixture of thoria plus I per cent. of ceria was found to give very little more light than pure thoria, the difference probably not exceeding 5 per cent., but on starting the kathode discharge the mixture heated up to incandescence more rapidly, and on stopping the discharge cooled more rapidly than the pure thoria. At the same time it was found that with an intensity of kathode rays that gave a brilliant light both with pure thoria and with the Welsbach mixture, a mixture of 50 per cent. thoria and 50 per cent. ceria, and also a piece of mantle composed of pure ceria, gave prac- tically no light, becoming barely red-hot. The maximum luminosities could only be obtained at a critical and highly unstable degree of vacuum, which rendered accurate photometrical measurements impossible, but with pure thoria the amount of light under favourable conditions was estimated at at least 150 candle-power per square inch of incandescent surface, this being obtained with an expenditure of electric energy at about $000 volts pressure of approximately one Watt per candle. : The kathode rays were found to havea reducing action on the oxides, which became discoloured under the bombardment, the discoloration disappearing owing to re-oxidation on the ad- mission of a small quantity of air. Air so admitted while the tube was working was rapidly absorbed, and after the process of admitting air and absorbing it had been repeated several times, the degree of exhaustion which gave the maximum incan- descence was found to have altered considerably, the residual gas having apparently become less conducting. In place of air, oxygen and hydrogen were separately used as the residual gas, but without any difference in the luminosity. These experiments show that thoria and ceria, both alone and mixed, behave quite differently when heated by kathode ray bombardment than when heated in a Bunsen flame. In the latter thoria plus 1 per cent. of ceria gives many times as much light as pure thoria alone, while when incandesced by kathode rays of equal intensity the difference, though in a similar direction, is only just appreciable. Again, in the flame, pure ceria gives just about the same amount of light as pure thoria, while with a given intensity of kathode ray bombardment thoria gives a brilliant light, while ceria gives practically none. In arriving at any satisfactory theory of the luminescent properties of the rare earths, these results will have to be taken into account. **A Quartz Thread Gravity Balance.” J. A. Pollock. The balance is of the horizontal, stretched, quartz thread type. One end of the thread is attached by soldering to a spring of peculiar construction ; the other end is attached to the axle of the vernier arm of a sextant. At the centre of the thread a bit of brass wire is attached by soldering, so that the thread crosses the wire, which is about two cm. long, at right angles. The centre of gravity of the bit of wire, which will be referred to as the ‘‘lever,” lies a little to one side of the thread, so that when the thread is untwisted the lever hangs vertically. The thread is stretched so that, in spite of the weight of the lever, it hangs almost horizontally. To make this NO. 1542, VOL. 60] By R. Threlfall and arrangement into a gravity balance, it is only necessary to turn the lever round the thread as axis, so that each half of the latter receives about three turns (3 x 360 degrees) of twist. The lever is adjusted till, under these circumstances, it hangs nearly horizontally. A discussion of the theory of the balance shows that if the twist be now reduced the centre of gravity of the lever will rise and the position of the lever become unstable soon after its centre of gravity rises above the horizontal plane through the thread. The nearly horizontal position of the lever is secured during observation by means of a microscope. which can be focussed upon the end of the lever, and which is rigidly attached to the framework of the instrument. Gravitational at- traction on the lever is thus balanced by the torsional rigidity of the quartz fibre, and the observations consist in noting the increase or diminution of twist, as applied at one end of the thread, necessary to bring the lever to its sighted position. The whole apparatus is enclosed in a tube which is air-tight, the vernier axle working through a sort of mercury stuffng-box. Exact thermometry is required, and is supplied by means of a platinum thermometer lying alongside the thread. The instrument only gives relative values of gravity, referring an excess, or defect, of gravitational force to the difference of gravitational intensity at two stations selected as having known constants, in the present case Sydney and Melbourne. The difficulties which have been met with during many years? work arise from the warping of the metallic parts of the in- strument under changes of temperature and in the imperfect elastic properties of fused quartz threads. The possible errors of a single observation are shown, from a discussion of the detail of the instrument, to amount to about one part in 300,000 of the value of g al any point, and by a dis- cussion of three journeys ‘between Sydney’ and Hornsby (N.S.W.), it is shown that the consistency actually realised is about one in 500,000 of g. ; Many journeys have been made with the instrument in New South Wales, Victoria, and Tasmania, from which the perfect portability of the instrument has been ascertained, as well as its convenience in practice.’ A single observation takes only a few minutes after the temperature has arrived at a maximum or minimum, but the packing and unpacking occupy more than an hour—in general about three hours are required. The weight of the total outfit, with ordinary appliances’ just as they came to hand in the laboratory, is 226 pounds, but this might be halved by making the appliances specially. The paper contains the complete theory of the instrument, working drawings ex- hibiting its construction, and an account‘ of experiments made with various modifications of the instrument. ‘*On the Electrical Conductivity of Flames containing Salt Vapours.”. By Harold A. Wilson, B.Sc. (Lond. and Vic.), 1851 Exhibition Scholar. Communicated by Prof. J. J. Thomson, F.R.S. ’ The experiments described in this paper were undertakem, with the object of following up the analogy between the con- ductivity of salt vapours and that of Rontgenised gases, and‘ especially of getting some information about the velocities of the ions in the flame itself. : They are to some exent a continuation of the research of which an abstract has already been published in the Proceedings of the Royal Society {‘*The Electrical Conductivity and Luminosity of Flames containing Vaporised Salts,’ by A. Smithells, H. M. Dawson, and H. A. Wilson, Roy. Soc. Proc., vol. Ixiv. p. 142). The paper is divided into the following sections :— (1) Description of the apparatus for producing the flame. (2) The relation between the current and E.M.F. in the flame. (3) The fall of potential between the electrodes, (4) The ionisation of the salt vapour. (5) The relative velocities of the ions in the flame. (6) The relative velocities of the ions in hot air. (7) Conclusion. The current with a large E.M.F, was found to be independent of the distance between the electrodes in the flame, provided both were hot enough to glow ; it was much greater when the hotter electrode was negative than when it was positive. When both electrodes were hot, the fall of potential between them was found to be very like that observed in the discharge through gases at low pressure. If one of the electrodes was cool, then nearly all the fall of potential occurred very near toit. Practically all the ionisation of the salt vapours appeared to take place at 70 the surfaces of the glowing electrodes. The velocities of the ions in the flame were estimated by finding the electric intensity required to cause them to move down the flame against the upward stream of gases. The positive ions of all the alkali metal salts had a velocity of about 60 emis. sec. The corresponding velocity of the negative ions was about cms. for one volt per cm. — In a current of hot air the corresponding velocities were Baral — (1) Negative ions of salts of Li, Na, K, Rb, Cs, Ca, Sr, and cms. Ba, 26:0 —— sec. (2) Positive ions of salts of Li, Na, K, Rb, and Cs, 7°2 cms: cms. sec. The greater velocity of the negative ions enables the phe- nomena of unipolar conduction &c., to be easily explained. Physical Society, May 12.—Prof. Perry, Vice-President, in the chair.—Dr. Lehfeldt read a note on the vapour pressure of solutions of volatile substances. The change in vapour pressure of a solvent due to the solution in it of a small quantity of volatile material has been calculated on the basis of Raoult’s rule for the corresponding case of a non-volatile dissolved body. The author has interpreted the formula of Nernst in the follow- ing words :—When asmall quantity of volatile substance is dis- solved in a liquid the vapour pressure of the liquid is altered in the ratio of the molecular fractional amount of solvent in the liquid to that in the vapour. In order to test’ this formula, it has been applied to the results of experiments made on four series of liquids, viz. alcohol with benzene and toluene, and carbon tetrachloride with benzene and toluene. _ In the case of normal solutions, such as carbon , tetrachloride in toluene, carbon tetrachloride in benzene, and benzene in carbon tetra- chloride, the agreement between the observed and calculated values of the percentage composition of the liquid was remark- ably good. | In the case of toluene in carbon tetrachloride the solution contained about 29 per cent. of the dissolved body ; and as the range of applicability of the formula had probably been exceeded, the agreement was not so good as in the previous examples. The mixtures containing alcohol show maxima of vapour pressure, and on this account the departure from the formula is so much more marked that it is impossible to apply it except in the case of very dilute solutions. The temperature used throughout the experiments was 50° C.—The Secretary read a note by Prof. W. B. Morton and Dr. Barton on the discussion of their paper, on the criterion for an oscillatory discharge of a condenser. In the discussion which followed the reading of the paper, it was pointed out that the result obtained, viz. that on taking into account the distribution of the current in the wire—a condenser having the critical capacity on the simple theory gives an oscillatory discharge—seems to be contradicted by the well-known fact that the resistance of the wire Is greater and the inductance less for oscillatory than ‘for steady currents. The explanation of the apparent paradox is to be found in the effect of the damping on the inductance. When the damping is great and the frequency small, as in the neighbourhood of the critical case, what may be termed the equivalent inductance becomes greater than the steady current value. It is shown that this increase in ‘‘ L.” outweighs the increase of“ R” in its effect upon the criterion for oscillatory discharge. An examin- ation of the expression for the equivalent inductance in the case of iron shows that it is greater than the steady current value if the ratio of one amplitude to the next is greater than e”!?0° where n is the frequency of the oscillation. Since the decrease of «],” with maintained oscillations is due to a surface con- centration of current, it is suggested that there must be an axial concentration in the case of damped vibrations. Following the method of Maxwell for determining the current density at a dis- tance from the axis of a wire, an expression for the current was in- troduced containing a damping coefficient. The ‘ quasi-ampli- tude” of the disturbance at any point in the wire was thus ob- tained. An examination of the result shows that making the damping zero indicates a surface concentration. If, on the other hand, the damping is great, the expression for the ampli- tude increases as the distance from the axis decreases, and we get an axial concentration. Assuming sufficient damping to produce this effect, it is shown that as we go through the point NO. 1542, VOL. 60] (3) Positive ions of salts of Ca, Sr, and Ba, 38 NATURE [May 18, 1 899 y = _, where a is the radius of the wire, we pass from a 2 greater value of current density in the inner parts to a less in the outer than would correspond to a uniform distribution throughout the wire. From general reasoning the authors think that if a rapidly damped disturbance is propagated into a wire from its boundary, and if the oscillations are slow enough to allow the current to penetrate to the core, we should expect to find an axial concentration in the latter stages of the phenomenon. Dr. Lehfeldt said that Prof. Lodge had pointed out, at the reading of the paper, that the solution the authors obtained changed character at the critical resistance. As this point had not been considered in the note, he supposed that the change in character made no difference to the results ob- tained, The Chairman expressed his interest in the proof of the existence of an axial concentration. —Mr. Addenbrooke ex- hibited and described a quadrant electrometer for application to alternating current measurements. The author has substituted for cylindrical quadrants two sets of flat plates, the top set being adjustable. In this way the range of the instrument is con- siderably increased. The ability to remove one or more of the top quadrants makes the needle very accessible. By lowering the needle on to the bottom quadrants, and then bringing down one of the top plates, the instrument can be carried with safety. One of the top quadrants can be worked up and down by a worm gear, and by this motion the ‘electrical zero” of the electrometer is obtained. The suspension consists of a flat phosphor bronze strip, the torsion of which is found to be per- fectly uniform, there being no fatigue effect. The case of the instrument contains windows, so that the needle can be viewed from two directions at right angles, and there are screw motions to centre the needle with respect to the quadrants. To reduce the effect of air convection currents upon the needle, the inside of the case is lined with cotton velvet. The quadrants are supported on brass bars passing through long ebonite sleeves inthe bottom of the instrument. This gives good insulation without the use of sulphuric acid, and there is no Leyden jar or condenser in connection with the needle. When using the electro- meter idiostatically with the finest strip, a light needle, and the quadrants one-tenth of an inch apart, a difference of potential of one volt will produce a deflection of about 5 mms. upon a screen two metres distant. Using the instrument hetero- statically with 100 volts on the needle one-fifth of an inch between the quadrants and half a volt acting across them a deflection of 200 mms. can be obtained. This sensitiveness is about twelve times as great as that got from instruments designed by Kelvin, Mascart, and Haga. Mr. Addenbrooke then showed how, in conjunction with a voltmeter and an ammeter, it was possible with his instrument to determine all the factors of an alternating current system. The increased sensitiveness of the electrometer renders it possible to measure currents of any magnitude with a very small waste of energy. Mr. Gaster pointed out that the measurement of self-induction with an electrometer could only be carried out practically if the current curve was a sine curve. He said that in curves ob- tained from a Ganz motor a correction amounting to 7 per cent. had to be applied. The Chairman said that even if the curve obtained was a sine curve, the electrometer was never used in this country for measuring Self-induction. Prof. Herschelasked if it were possible to adjust the quadrants after the needle had been charged Mr. Addenbrooke then purposely disturbed the position of the adjustable plate, and, after charging the needle, reduced the deflection to zero by the worm gear. The author said that for high voltages the curve of calibration was different to that obtained from the ordinary formula. The Chairman said that this discrepancy was probably due to want of perfect symmetry. In a paper read before the Royal Society by Perry, Ayrton and Mather, it was shown that the presence of the guard around the mirror of an ordinary electrometer was sufficient to affect the needle when working with high voltages. In working with the plates very close together he was afraid the symmetry would be liable to be disturbed by a slight tilting of the needle due to electrostatic attraction. The author ob- served that the plates were only very close together when working with low voltages. Chemical Society, May 4.—Prof. Thorpe, President, in the chair,—The following papers were read :—On the com- bustion of carbon disulphide, by H. B. Dixon and E. J. Russell. Carbon disulphide undergoes a phosphorescent combustion in air at temperatures below its ignition point, the lowest observed May 18, 1899] NATURE al value for which was 232°; prolonged heating of carbon disulphide at 230°, or prolonged exposure to bright light, causes slight decomposition. The decomposition of carbon bisulphide vapour by detonation is not propagated as an explosion, and no explosive wave could be propagated in mixtures of the vapour and oxygen containing less than 4o per cent. of the latter.— The action of nitric oxide on nitrogen peroxide, by H. B. Dixon and J. D. Peterkin. A very slight increase of volume occurs on mixing nitric oxide with nitrogen peroxide at 27°, but a con- siderable expansion attends the mixing of inert gases like nitrogen with the peroxide, owing to dissociation of the latter ; these results may be explained by the equation NO, — NO + NOs on the supposition that at 27° the dissociation is nearly complete.—On the mode of burning of carbon, by H. B. Dixon. It is shown that Lang’s view that carbon dioxide is the first product of the combustion of carbon, and that carbon monoxide is only produced by the subsequent reduction of the dioxide, is invalid. —Crystalline glycollic alde- hyde, by H. J. H. Fenton and H. Jackson. The aqueous syrup containing glycollic aldehyde obtained by heating dihydroxy- maleic acid with water, yields a hexose, C,H,,O,, on evapor- ation; during the latter process a small proportion of crystalline glycollic aldehyde sublimes ; when first dissolved in water the aldehyde has the composition C,H,O,, but after about twenty- four hours the molecular composition becomes C,H,O.,—On the blue salt of Fehling’s solution and other cuprotartrates, by O. Masson and B. D. Steele. The blue salt of Fehling’s solu- tion when dried zz vacuo has the composition K,C),HgCuyOj,, 4H,O, and contains a complex negative radicle of which copper is a part ; none of the copper is electropositive.—The prepar- ation of acid phenolic salts of dibasic acids, by S. B. Schryver. —The maximum pressure of naphthalene vapour, by R. W. Allen, The author has prepared, from new experimental data, tables showing the vapour pressure of naphthalene and giving the weight of naphthalene required to saturate a cubic metre of gas at temperatures ranging from o° to 130°.—Scoparin, by A. G. Perkin. Scoparin, the colouring matter of broom, s probably a methoxyvitexin.—On a new .compound of arsenic and tellurium, by E. C. Szarvasy and C. Messinger. The compounds of arsenic with elements of the oxygen-sulphur series which are most stable at high temperatures are As,O,, As,S,, As,Se; since the differences between the molecular weights in this series of compounds are 15 and 16, it: was thought probable that the compound As,Te3 should be formed at high temperatures. The authors have obtained this com- pound.—The action of hydrogen peroxide on secondary and tertiary aliphatic amines. Formation of alkylated hydroxyl- amines and oxamines, by W. R. Dunstan and E. Goulding.— The enantiomorphously related tetrahydroquinaldines, by W. J. Pope and S. J. Peachey. The authors have separated synthetic tetrahydroquinaldine into a dextro- and a lzvo-rotatory isomeride by crystallising its salts with camphorsulphonic acids. Entomological Society, May 3.—Mr. R. McLachlan, F.R.S., in the chair.—Dr. A. L. Bennett exhibited various insects which he had collected in the French Congo, They included a species of Mantidz remarkable for its very striking resemblance in coloration to a piece of bark.—Mr. F. Enock exhibited a living specimen of Mefa cénerea infested with a number of minute red Acarz on the ventral surface of the abdomen. Healso showed eggs of Mefa and Wotonecta lying tm situ in decayed leaf-stalks of A/zsma, and described the mode of oviposition as observed by himself in both of these genera. He then exhibited a living example of the remarkable aquatic Hymenopteron—Prestwichza aguatica, Lubb., and said it was one of a brood of nine, including eight ? 9 and one 6, that issued on May 1 from a single egg of Colyméetes found on September 5, 1898.—Mr. Merrifield showed some specimens of Hemaris bombyliformzs, Esp., with the scales still covering the central portions of the wings. He said thee scales, which are present immediately after the emergence of the insect but soon become detached, may be rendered adherent by allowing a very weak solution of indiarubber in benzoline to run over the wings. —Mr. C. H. Dolby-Tyler communicated a paper on the development of Ceroplastes roseatus, Towns. and Cockl. Mathematical Society, May 11.—Prof. H. Lamb, F.R.S., Vice-President, in the chair.—Major MacMahon, R.A., F.R.S., communicated some results he has obtained in the theory of NO. 1542, VOL. 60] partitions. —Mr. H. M. Macdonald read a paper on the zeroes of aspherical harmonic, P,,”"(«), considered as a function of 7. —Mr, W. F. Sheppard gave an account of his paper on the statistical rejection of extreme variations, single or correlated (normal variation and normal correlation). MANCHESTER. Literary and Philosophical Society, April 25.—Mr. J. Cosmo Melvill, President, in the chair.—At this the annual general meeting, Mr. R. H. Inglis Palgrave, F.R.S., and Prof. William Ramsay, F.R.S., were elected honorary members of the Society.—The annual report (as amended) and the state- ment of accounts were adopted, and the following were elected officers and members of the Council for the ensuing year :— President, Prof. Horace Lamb, F.R.S. ; vice-presidents, Prof. Osborne Reynolds, F.R.S., Mr. Charles Bailey, Mr. J. Cosmo Melvill, and Prof. W. Boyd Dawkins, F.R.S. ; secretaries, Mr. R. F. Gwyther and Mr. Francis Jones; treasurer, Mr. J. J. Ashworth; librarian, Mr. W. E. Hoyle ; other members of the Council, Prof. H. B. Dixon, F.R.S., Mr. Francis Nicholson, Mr. J. E. King, Mr. R. L. Taylor, Mr. F. J. Faraday, and Mr. W. H. Johnson.—At the ordinary meeting held afterwards, Prof, Dixon described an apparatus for bring- ing together nitrogen peroxide and nitric oxide in order to determine whether any combination occurs between the gases. PARIS. Academy of Sciences, May 8.—M. van Tieghem in the chair.—On the absolute measurement of time, deduced from the laws of universal attraction, by M. G. Lippmann. The unit of time suggested is based upon the proposition that the numerical value of the Newtonian constant is independent of the units of length and mass, and depends uniquely upon the choice of the unit of time. Inversely, the magnitude of the interval of time taken as unity is determined without ambiguity when the numerical value of the Newtonian constant which corresponds to it is given.—Anatomical and physiological characters of plants rendered artificially Alpine by alternation between extreme temperatures, by M. Gaston Bonnier. Alpine temper- ature conditions were imitated by keeping the plants in an ice box during the night, and exposing fully to the sun during the day. The petioles of the leaves develop more rapidly under these conditions, and the leaves, which are smaller and thicker, have a more highly developed layer of pallisade tissue, and frequently the reddish coloration of Alpine plants. The flowers are relatively larger and more highly coloured than those grown under ordinary conditions. — M. Prillieux was elected a member of the Botanical section, in place of the late M. Naudin.—On the circumstances which modify the images reflected by a mercury bath, and on the transmission through the soil of vibrations produced at the sur- face, by M. G. Bigourdan. In the hope of securing a steadier mercury surface, the bath was placed at varying distances from the surface of the earth. It was then found that two quite distinct classes of earth tremors could be distinguished, the one slow and regular, to which the name undulation is given, the other rapid and irregular vibrations.—On_ the pencils which correspond to the case where the series of Laplace is limited in one direction, by M. C. Guichard.—The groups of the order p' @, # being a number greater than g, by M. Le Vavasseur.— On the electric capacity of badly conducting bodies, by MM. I. I. Borgmann and A. A. Petrovsky.—On an intense source of monochromatic light, by MM. Ch. Fabry and A. Perot. ‘Bhe new source suggested is the electric arc between two surfaces of mercury 272 vacuo. The mercury is contained in two concentric glass tubes, the inner one only just separating the two mercury surfaces. On giving the tube a slight shock a momentary connection is set up, and the arc starts. For a perfectly stable arc a potential of about thirty volts is necessary, and a current of from two to three amperes. The light is not perfectly mono- chromatic, but may be easily rendered so by the interposition of cells containing suitable absorption media. Thus, a mixture of didymium chloride and potassium bichromate cuts off all rays except the green ray, the most useful ray for general purposes. —On the ratio of the atomic weights of hydrogen and oxygen, by M, A. Leduc. By taking into account the increase of pressure observed to take place when hydrogen and oxygen gases are mixed, the number for the ratios of the atomic weights deduced from the density of detonating 72 gas (15°S98), is increased to 15°878, a number sensibly in agree- ment with the 15°88 found by the author by the gravimetric method.—On the increase of pressure produced by the mixture of two gases, and on the compressibility of the mixture, by M. Daniel Berthelot. The formule proposed by the author in a previous paper are applied to the gas mixtures, SO,+CO,, N,+O., and H,+Oy,, and the results compared with the experi- ments of Sacerdote, Leduc, Rayleigh, and the author. The agreement is very close.—Researches on the separation of traces of bromine existing in chlorides, by M. H. Baubigny. A strong solution of the chloride, to which a large amount of copper sulphate has been added, is treated with potassium perman- ganate in the cold, and the whole reduced to dryness 2” vacuo. The whole of the bromine is thus given off, together with a little chlorine ; the original method proposed by the author and M. Rivals is then applied to this mixture. Two test analyses show satisfactory results, even when only ‘005 gram of bromide was present with 12 grams of chloride.—On the impurities of aluminium, by M. Adolphe Minet.—On mag- nesium phosphide, by M. Henri Gautier. The phosphide Mg;P, was prepared ina pure state by.the direct combination of the elements in a stream ofhydrogen. Pure PH, is obtained on treating this with water.—On the flame of hydrogen, by MM. Schlagdenhauffen and Pagel. The violet-blue colour of a hydrogen flame obtained when the gas is prepared from zinc is not due to sulphur, as proposed by Salet, but selenium. Some selenium is invariably left behind in the residue, probably as lead selenide.—Hydrogenation of acetylene in presence of nickel, by MM. Paul Sabatier and J. B. Senderens. A mixture of hydrogen and acetylene acts vigorously ~upon reduced nickel, even in the cold, ethylene, ethane, and liquid hydrocarbons being produced in quantity.—On the dextrines arising from saccharification, by M. P. Petit.— Method for rapidly measuring the dimensions of small objects, independently of their distance. Application to pupillometry and to laryngometry. Illusion due to the muscular sense in the - appreciation of the size of objects, by M. Th. Guilloz.—Patho- logical physiology of pregnancy, by MM. Charrin and Guille- monat.—The influence of freezing upon the development of the hen’s egg, by M. Etienne Rabaud. The eggs were not killed by exposure to —15°C., but the development was markedly affected, and that permanently.—Some remarks on the Haementerta costata of Miller, by M. A. Kowalevsky.—On the existence of a fauna of Arctic animals in the Charente at the Quaternary epoch, by MM. Marcellin Boule and Gustave Chauvet.—New researches on the caverns of Padirac, by MM. Armand Viré and Etienne Giraud.—On the ascent of the Balaschoff on March 24, by M. G. Le Cadet. DIARY OF SOCIETIES. THURSDAY, May 18. Roya Society, at 4.30 —Bakerian Lecture : The Crystalline Structure of Metals: Prof. J. A. Ewing, F.R.S., and W. Rosenhain.—The Yellow Colouring Matters accompanying Chlorophyll and their Spectroscopic Relations: C. A. Schunck.—The Diffusion of Ions into.Gases: J. S. Townsend.—The Diurnal Range of Rain at the Seven Observatories in connection with the Meteorological Office, 1871-1890: Dr. R. H. Scott, F.R.S, INSTITUTION OF ELECTRICAL ENGINEERS, at 8.—Electric Locomotivesin Practice and Tractive Resistance in Tunnels, with Notes on Electric Locomotive Design: P. V. McMahon. Cuemicac Society, at 8.—Corydaline, Part VI.: Dr. J. J. Dobbie and A. Lauder.—Oxidation of Furfural by Hydrogen Peroxide: C. F. Cross, B® J. Bevan, and T. Freiberg. FRIDAY, May to. RovatInstTiTuTION, at 9.—Runic and Ogam Characters and Inscriptions in the British Isles : The Lord Bishop of Bristol. EprDEMIOLOGICAL Society, at 8.30.—A Study of Enteric Fever in the Netherlands: Prof R. H. Saltet. TUESDAY, May 23. Roya. INSTITUTION, at 3.—Recent Advances in Geology: Prof. W. J. Sollas, F.R.S. c Roya PHOTOGRAPHIC SOCIETY, at 8.—Corea: Mrs. Isabella Bishop. WEDNESDAY, May 24 GEOLOGICAL SociErTy, at 8.—On the Distal End of a Mammalian Humerus from Tonbridge : Prof. H.G. Seeley, F.R.S.—On Evidence of a Bird from the Wealden Beds of Ansty Lane, near Cuckfield: Prof. H. G. Seeley, F.R.S.—On the Rhyolites of the Hauraki Goldfields (New Zealand): J. Park and F. Rutley.—On the Progressive Metamorphism peseme “‘Dalradian "’ Sediments in the Region of Loch Awe: J. B. ill. NO. 1542, VOL. 60] NATURE [May 18, 1899 THURSDAY, May 25. Rovat InstiTuTION, at 3.—Water Weeds: Prof. L. C. Miall F.R.S. FRIDAY, May 26. Roya Institution, at 9.—Climbs and Explorations in the Andes: Sir W. Martin Conway. PavsICAL Society, at 5.—On the Thermal Properties of Normal Pentane, Part 2: Prof. S. Young and Mr. Rose-Innes.—On the Distribution of Magnetic Induction in a Long Iron Bar: C. G. Lamb. BOOKS, PAMPHLETS, and SERIALS RECEIVED. Booxs.—Cours Elémentaire de Zoologie : R. Perrier (Paris, Masson).— Chapters on the Natural History of the U.S.: Dr. R. W. Schufeldt (Gay). —Dus Tierreich, 7 Liefg.: Profs. Canestrini and Kramer (Berlin, Fried- lander).—Ditto, 8 Liefg.: Prof. K. Kraepelin (Berlin, Friedlander).— Electromagnetic Theory : O. Heaviside, Vol. 2 (Alectrician Company).— The Tides Simply Explained: Rev. J. H. S. Moxly (Rivingtons).—A Manual of Surgical Treatment: Prof. W. W. Cheyne and Dr. F. F. Burghard, Part _r (Longmans).—Physique et Chimie Viticoles: A. de Saporta (Paris, Carré and Naud).—The Aborigines of Tasmania: H. Ling Roth, 2nd edition (Halifax, King). PAMPHLETS,—Die Elemente des Erdmagnetismus, &c. : Dr. H. Fritsche (St. Petersburg).—Man the Microcosm: L. Hall, Part 1 (Williams).—Die Lokalisation Morphogenetischer Vorgange : H. Driesch (Leipzig, Engel- mann).—Die Aufstellung der Tiere in Neuen Museum zu Darmstadt: G. von Koch (Leipzig, Engelmann).—Siebenter Jahres-Bericht des Sonnblick- Vereines fiir das Jahr 1898 (Wien). SERIALS —Science Gossip, May (Strand).—Botanische Jahrbiicher, Siebr. Bd. xr and 2 Heft (Leipzig).—Fortnightly Review, May (Chapman).— Zeitschrift fiir Physikalische Chemie, xxviii. Band, 4 Heft (Leipzig). —Himmel und Erde, April (Berlin).—Natural Science, May (Pent- land).—Journal of Botany, May (West),—Observatory, May (Taylor). —Journal of the Chemical Society, May (Gurney).—Geographical Journal, May (Stanford).—Monthly Weather Review, January (Washington).— Proceedings of the Royal Society of Edinburgh, Vol. xxii. pp. 361-440 (Edinburgh).—Engineering Magazine, May (Strand).—Physical Review, March (Macmillan).—Scientia, No. 3 (Paris, Carré).—Journal of Applied Microscopy, March (Rochester, N.Y.).—L'Anthropologie, Tome x. No.2 (Paris).—Record of Technical and Secondary Education, April (Mac- millan).—Memoirs of the Boston Society of Natural History, Vol. v. Nos. 4 and 5 (Boston,.Mass.).—American Journal of Mathematics, April (Balti- more).—Psychological Review, May (Macmillan).—National Geographic Magazine, May (Washington).—American Journal of Science, May (New Haven).— Botanischer Jahrbiicher, Sechsr. Band, v. Heft (Leipzig). CONTENTS. PAGE Dravels in'New Guineaieu-n ace) «ss = eee eeeag) Our Book Shelf :— Smith: ‘‘The Philosophy of Memory, and other Essays.’—H. W.B. .. . 51 Jung and Schréder : “Das Heidelberger Schloss und Seine Garten in alter und neuer Zeit und der Schloss- garten zu Schwetzingen.”—John Weathers . . . 52 Wood: ‘‘Graduated Test-papers in Elementary Mathematics ” bc. 0) ah AOA ORI ERE Oc Munro: ‘‘ The Story of the British Race” ..... 52 Letters to the Editor :— Fourier’s Series.—Prof. A. A. Michelson; M. Poincaré” . (See ere ieee cite >< Cee EE A Note upon Phosphorescent Earthworms.—Frank E- Beddard (hi RAS Sire raesmaien k= sin 4x for values of x which lie between a and —7. The proof of the theorem, whether in this special case or in more general cases, consists in summing the series; and the result obtained in this special case is that the sum of the series is 3(a—«), when x lies between 0 and 7, —4(r+.~), when x lies between 0 and —7z, oO , when «=o. Prof. Michelson has found a difficulty in this result in that, whereas the sum of any number of terms of the series is a con- tinuous function of x, the sum of the series is a discontinuous function of x. If I have not misunderstood him, he contends that for extremely small positive values of « the sum of the series should be regarded as indeterminate and as having any value between o and 47, and I understand him to support this con- tention by the consideration that when z terms of the series are taken, so that w being extremely small x is finite, such an indeterminateness is found. Such a position involves a misconception of the meaning of June 1, 1899] NATURE IOI the ‘‘sum of an infinite series.” When 7,+2.+ ... is the series, the terms being uniform functions of x, the sum of the series for any value of .x is the limit of the sequence of numbers Uy, My tty, Uy +Ug+ug, ... in each of which x has the given value ; the limit of the sum of the series when =0, is the result obtained by /ivs¢ summing the series for a finite value of x, and afterwards diminishing x without limit ; the sum of the series when «=0 is the result obtained by /s¢ substituting o for « in the functions 7, w%, ... and afterwards forming the limit of the sequence 7%, %,+%, ..... In the example in question, the re- sults thus obtained are 4m and o respectively. The results that can be obtained by summing the series to 7 terms, diminishing xindefinitely, increasing 7 indefinitely and keeping 7x finite, generally do not coincide either with the sum for «=o or with the limit of the sum for x=0, when these are different. Such results may, as I have pointed out in a previous letter, be useful for purposes of illustration, but they are quite beside the mark when it isa question either of the statement of Fourier’s theorem or of the sum of Fourier’s series. M. Poincaré, in his letter printed in NATURE for May 18, does not assert that the sum of the series can be obtained by allowing .» to approach zero and 7z to increase at the same time, in such a way that z* remains finite; but he states that Prof. Michelson is perfectly right in contending that the result of this process is indeterminate. So far as I am aware this contention has not been called in question in the course of the discussion. Oxford, May 19. A. E. H. Love. Bessel’s Functions. THE remarks of ‘*C. G. K.”’ (p. 74) concerning the defects of style which are frequently observed in the writings of scientific men, lead me to point out a grammatical error which is creeping into mathematical literature. I allude to the use of the incorrect phrase ‘* Bessel Functions ” in the place of ‘‘ Bessel’s Functions.” In certain cases the name of a person may be converted into an adjective by the addition of an appropriate termination, of which such words as A/zzabethan and Vectorzan are examples ; but to use the name itself (which is a noun) as an adjective, isa violation of one of the most elementary rules of grammar. When the conversion of a proper noun into an adjective would be cumbrous or inelegant, the only correct mode of expression is to use the gevztzve case. If, therefore, we reject such an adjective as ‘* Bessellian” on the ground of its inelegance, we must use the phrase ‘‘ Bessel’s Functions,” that is functions of Bessel. The absurdity and incorrectness of the phrase ‘‘ Bessel Functions” is at once seen by comparing it with such phrases as ‘* Green Theorem,” ‘‘ Chrystal Algebra,” ‘* Love Elasticity.” The correct use of the genitive case is a subject upon which considerable misapprehension has existed. Thus we find in the Prayer Book the phrase ‘‘ For Jesus Christ His sake,” instead of ** For Jesus Christ’s sake.”” The error arose from the fact that the compilers of the Prayer Book were ignorant that the *s is not a conception of the pronoun /zs, but is the old Teutonic genitive which still exists in most German languages. Fledborough Hall, Holyport, May 28. A. B. BASSET. “The Art of Topography.” In your issue of March 23 (No. 1534, vol. lix.) appears a review of ‘* Recherches sur les Instruments, les Méthodes et le dessin Topographiques, par le Colonel A. Laussedat,” signed by ““T. H. H.” The review brought to my attention several points of interest upon which I beg leave to comment. Regarding planetable instruments, the reviewer says ‘‘ that * Russians and Americans’ use very complicated instruments.” Of the Russian instruments I have no knowledge, but this is certainly not true of the American. The U.S. Geological Survey makes use of the planetable to a greater extent than any and all other organisations in America, fully two hundred of these instruments being con- stantly in use. The instruments used are remarkable in simplicity and efficiency, are reasonably light, portable and accurate. The instruments are of a model designed by Mr. Willard D. Johnson, of the Survey, and are fully described on pages 79 to 89 of Monograph xxii. of the U.S. Geological Survey, entitled “* Manual of Topographic Methods,” by Mr. Henry Gannett. This work also treats of the methods of accomplishing topo- graphic mapping by the Geological Survey. Mr. Gannett explains the use made of the planetable, and shows that all work is controlled by points, located by triangulation or other means NO. 1544, VOL. 60] dependent upon numerical measurements and carefully com- puted. The triangulation is carried on with eight-inch theo- dolites reading, by micrometer microscopes, to two seconds. The instructions to triangulators include the order that points must be selected and arranged so as to best control the area under survey, and that vee points at least should be located on each atlas sheet of the map. Since these sheets differ in area in different parts of the country, ranging from 1/16 of a square degree to a square degree, the distance between tnangulation stations necessarily varies considerably. After the primary triangulation points are located in an area, dependence upon the planetable is absolute for the ‘‘ secondary ” triangulation within that area, the control, both horizontal and vertical, is carried on by use of this instrument. If the surveyor using a planetable for graphic work starts from accurately located points with check point available, he very soon dis- covers any ‘‘accumulation of error,” in that it is impossible to make the several locations check one with another. In regard to the use of ‘‘continuous contours” to express relief, the ‘‘Commission of 1826” seems to have drawn the remarkable conclusion that for scales less than I : 10,000 this system is insufficient. The Geological Survey publishes topographic maps which vary in scale between I : 9600 and I : 250,000 (1 inch to 800 feet and 1 inch to 4 miles about, respectively), and on these maps the contour interval varies between 5 feet and 200 feet. The expression of relief is, I think, in these cases satisfactory, at least so far as giving accurate information is concerned ; the artistic effect is very good also, especially when the topographic features are large and the slopes steep, cliffs appearing as broad heavy lines where differentiation of the individual contours is impossible. About 1890, the use of mercurial barometers was abandoned by the Geological Survey, and trigonometric methods for obtain- ing heights were adopted. At the present time the primary heights are determined by spirit-levelling, from which elevations are carried in connection with the triangulation or by lines run with vertical angle readings and carefully measured distances. The use of the aneroid barometer is only allowed in inaccessible areas between the known elevations, and must be frequently checked. The experience of the writer in widely separated regions in the United States, in obtaining differences of eleva- tion with the aneroid, leads him to the conclusion that, as a rule, the instrument fails to record differences as accurately when carried from a higher to a lower region as it does when the change of elevation is in the opposite direction. Also, that an aneroid which has been used in a region of elevation of given range must be given time to accommodate itself, if it be required to do good work in a region of greater or less elevation than that in which it has been used. The principle and construction of the aneroid is such that it never can be accepted as an instru- ment of precision except within well-defined limits, with frequent comparison with known elevations. The Survey has in use several hundred aneroid barometers, but no confidence may be had in any one of them unless frequently checked, as stated. It will be seen that the methods now in use in America agree more closely with those practised by the British Govern- ment, at least so far as the Colonial surveys are concerned, than with any other of the European surveys. Re dele (Cr The Heating of the Anti-Kathode in X-Ray Work. SINCE the beginning of X-ray work the heating of the anti- kathode has caused great difficulty, and with the introduction of the Wehnelt interrupter it is even more important that this should be prevented. In other words, we all along have had more energy from the coil than could be utilised in the Crookes’ tube. Many workers like myself have tried to remedy this, and various plans have been adopted to keep the anti-kathode cool. It occurred to me that if we could get a piece of platinum, fused into the glass tube itself, to act as the anti-kathode, and placed opposite the kathode, this object might be attained. Such a tube, after many attempts, has at last been made ; and although the first experiments have only been successful in making small tubes, others of a larger size are at present being attempted. The advantage of this method will easily be seen, because the heating of the piece of platinum can be prevented by placing the whole tube in a fluid cooling mixture or other- wise. These tubes are difficult to make at present, but I possess one which has retained its vacuum for some weeks, 179 Bath Street, Glasgow, May 28. J. MACINTYRE. NAT ORE [JUNE 1, 1899 Variation of Species. On p. 181 of Wallace’s ‘‘ Darwinism,” ed. 1889, this passage occurs :—‘‘ Let us suppose that a given species consists of 100,000 individuals of each sex, with only the usual amount of fluctuating external variability. Let a physiological variation arise, so that 10 percent. of the whole number—10,000 in- dividuals of each sex—while remaining fertile z7fer se become quite sterile with the remaining 90,000. This peculiarity is not correlated with any external differences of form or colour, or with inherent peculiarities of likes or dislikes leading to any choice as to the pairing of the two sets of individuals. We have now to inquire, What would be the result ?” I have here attempted to investigate this question alge- braically. A. We shall suppose, as Dr. Wallace does, that the number of males in the species is the same as the number of females. Each of these numbers we shall denote by unity. For con- venience, we shall speak of the number of either sex as the number of the species. Let then x = the number of the normal species, and y = the number of the variant variety, at any given stage of the change above described. If in any given generation (x, 7), the ratio, which the number of the variant individuals, born in a family of the normal species, bears to the total number of young born in that family, be denoted by %; and if («’, y’) denote the generation which succeeds (1, y); then must Ky! 22 xT —2) 3 gy? phx? 5 with the relation By — at y— 1s because the total species remains constant in number of in- dividuals. Now, if the variants succeed in establishing themselves as a new species, and the above two generations belong to the per- manently settled state of the whole species, we must have x’ =x, and 7/=y. Consequently, to determine have the equations (1=£)a? _ y+ ha? x .. (I-—A)x=2x2—2x4+13 vw. £=4(3-24+ N22 62 +1). To take Dr. Wallace’s example, put =*1. Then B—nOOl Osis. iey.— eA 2) eras x, y under this condition we > X+yVY=15 or H='56492)..., j= "43508)...- Thus, taking Dr. Wallace’s number 100,000, we find that, ultimately, the normal species will number 88,508 and the variant 11,492 These numbers differ but little from Dr. Wallace’s, but they represent the final distribution of the original species into twe species. Another possible distribu- tionis given by the numbers 56,492 and 43,508. If by any chance the first permanent distribution be disturbed materially, then the total species might reach the second permanent state. If, however, at any time the parent species were to cease to produce the variants, then the latter would quickly disappear. They could be saved from extinction only by the ceasing of intermarriage between the two species. For, if (x,, y,,) denote the wth generation from the one (x, y) in which the variants ceased to be produced by the normal species, then 25 SURE If 2=4, and x="9, y="I, as in Dr. Wallace’s case, then X42 Ys 2: (81)* : ‘oo000001 ; so that the original species of 100,000 would have no variants left at all. The disappearance of the variants is due to the two facts, (1) that the total number of the two species together is constant, (2) that the number of unfruitful unions is very large in proportion to the number of unions possible to the smaller species. For example, if the variants be ‘1 of the whole species, the probability will be that ‘9 of their unions will be unfruitful ; but that “9 of the unions of the normal species will not be unfruitful. B. We shall now consider the case when the unions between the two varieties are not sterile, and the hybrids are also fertile znter se and with the parent varieties. NO. 1544, VOL. 60] xm: yn Let the relative, effective, fertility of the hybrids and mongrels, z7z/er se and with the parent varieties, be denoted by the factor £, which we shall assume to be always less than unity. Also, let the effective fertility of the normal species in the pro- duction of variants be denoted by the factor 4 ; and let 2 denote the number of the hybrid variety in the generation (., y, =). Then the equations which determine the stable and permanent condition, if there be one, are (Lam)? 9 + x? {ot y #2)? — 0" yf Xk = 2 x y z otk Nahas) PECL . (6) and Af a \ B=5\3 ~HENH— Ou+15¢ - ein! alt) The roots of u7—64+1=O are "17158... and 5°82842.. . As we suppose u less than 1, it follows that in no case must exceed the lower root, "17158 .. . 55 (0) From (7) it follows that 8 must >. From (6) it follows that 1-4 must >42'B, or =42'B ; *, I-—p must >4hk'; , Also must not >“, . 4h -". & must not >°5 - (9) . . (10) To take Dr. Wallace’s example, put «= ‘I. We find, then, that £2” must not > ‘225. If we put £4’= "225, and solve for %, we find that h—2AQe , or 658 But £2’ must not >*225; hence *# must not lie between 242%, . . and 658)... siemsibya(Q)i£ must not —sa2 ieee Take, for example, = 2. Then by (7), B='225969. . . or "354031 . By (10) we must reject the second value of B. Adopting the first value, we find from equations (2) and (1) the following two solutions, = +7OSiciis yn LOA REE 2 OOGTe and ea eetots) OL e052 Here the effective fertility of the hybrids, zzte se and with the parent varieties, must not exceed 34 per cent. of that of the parent varieties ; and in no case must it exceed 50 per cent. of the latter. Also, in no case must the parent species supply more than, or even as much as, 18 per cent. of its total progeny to the variant species. C. If no hybrid unions occur, and the two varieties supply individuals to each other in such a way that, taking the progeny of the generation («, v), a fraction A of the x progeny belongs to the y variety, while a fraction p of the y progeny belongs to the x variety (where A and w are proper fractions), it is easy to prove that in the ultimate, established, state of the total species aHrysi era. Therefore, if A=, the species will be, in its final state, equally divided between the two varieties. The equations for the established state are, since now there is no intermarriage, XA AKT MY _I = MY TEAK x ia — las whence AX= My 3 Z.é. Xiyprimia. This may also be proved by direct calculation, Woodroffe, Bournemouth. J. W. SHARPE. June 1, 1899] NADORE 103 ON SOME RECENT ADVANCES IN SPECTRUM ANALYSIS RELATING TO INORGANIC AND ORGANIC EVOLUTION} N the last lecture I dealt with that new development of spectrum analysis which has enabled us to dis- cuss, with greater fulness*than was possible before, the various chemical conditionings in the different regions of our system as marked out for us by the Milky Way. I now have to refer to another development in a somewhat different direction. We have, as I think you will agree, by the discussion of the relation of the celestial bodies of all sorts to the Milky Way, demonstrated that the evolution of the cosmos in all probability took place from the gradual condensation of swarms of meteorites ; and that such swarms are still more numerous there, and give rise to the new stars, bright-line stars and variable stars which are most numerous in its plane. When this work was begun our knowledge was so incomplete that a continuous chain of chemical facts was out of the ques- tion ; but, thanks to the advances to which I have now to refer, we can deal with this cosmical evolution from a chemical standpoint, and what we have to do to-night is to consider the result of this inquiry. I may begin by saying that now the gaps in our know- ledge have been filled up, we find ourselves in the pre- sence of a chemical evolution which is really majestic in its simplicity. Such a chemical evolution was suggested by me many years ago now, to explain the few stellar facts with which we were then familiar ; but I do not pro- pose to take up your time with any historical allusions ; 1 must point out, however, that we to-night are in a very much better condition to consider this problem than we have ever been before, because at the present moment we have tens of thousands, | might almost say hundreds of thousands, of coordinated facts to go upon. The first point I have to refer to is this: we have brought the sun and the stars together into line in all matters relating to the discussion of the effects of higher temperatures. The photographs taken during the recent solar eclipses show that when we deal with the hottest part of the sun that we can get at, which is hotter than that part of the sun which produces the well-known absorption spectrum marked by the so-called Fraunhofer lines, we are not in an unknown territory at all, but are brought face to face with similar phenomena to those in the atmospheres of stars which are hotter than our sun. The bright-line spectrum of the sun’s chromosphere seen during an eclipse shows us the effects produced by heat in the hottest part of the sun that we can reach ; these we can compare with the dark lines of a star which contains absorption lines very different from those represented by the Fraunhofer lines, and we find that they correspond almost line for line. In this manner then we have an opportunity of correlating all the facts which have been obtained during the last, let us say, thirty years, in relation to the sun, with more recent facts than have been gathered with regard to the stars. In this work we were, by hypothesis, watching the effects of dissociation as the temperature rose higher and higher; but if we change our point of view, if we consider the phenomena no | longer from the point of view of dissociation but from | that of evolution, we find at once that the facts recently | garnered carry us very far indeed along a new line of | thought. Let me give you an idea of what I mean. Let us deal, for instance, with well-known chemical compounds, say chloride of sodium, that is common salt, and oxide of iron, that is iron-rust. We have no difficulty in recog- nising the fact that chlorine and sodium in one case and oxygen and iron in the other must have existed before 1A Lecture to Working Men, delivered at the Museum of Practical Geology on Monday, April 24, by Sir Norman Lockyer, K.C.B. NO. 1544, VOL. 60] | their compounds, common salt and iron rust, could be formed or associated. Water is split into hydrogen and oxygen at a high temperature, so that there is a temper- ature above which the two gases would remain in contact but uncombined ; when the temperature falls water is produced. Dissociation, therefore, in all its stages must reveal to us the forms the coming together of which has produced the thing dissociated or broken up by heat. If this be so, the final products of dissocia- tion or breaking up by heat must be the earliest chemical forms. Hence we must regard the chemical substances which visibly exist alone in the hottest stars as represent- ing the earliest evolutionary forms. That, I think, is pretty obvious. If we were only dealing with ordinary chemical forms it might be objected that it was only a question of seezag ; that all chemical substances were really present in the reversing layer, that is the part of the atmosphere of the stars which we can study, but some only made their ap- pearance ; but I shall show later that the orderly pro- gression includes lines of substances which we cannot see at all and others which we can only see at the highest possible temperatures in our laboratories. Two or three times over I have used the words “evolution” and ‘evolutionary forms.” What do these words really mean ? ; Perhaps I can give an idea of this by referring to another line of work altogether in which the word is fre- quently used and thoroughly understood. It is important that I should do this for another reason, which you will gather later. That line of work has to do, not with inanimate forms, like the chemical elements and the stars, but with living things, with so-called organisms. Some of my audience to-night doubtless remember Huxley’s lectures here in 1860 On the Relations of Man to the Lower Animals, and most of you know that what we now recognise as one of the greatest triumphs of the century just ending was the determination of the truth of a so-called “organic evolution” in which we have, I suppose, the most profound revolution in modern thought which the world has seen. That evolution tells us that each kind of plant and animal was not specially created, but that successive changes of form were brought about by natural causes, and that the march of these forms was from the more simple to the more complex. Organic evolution, in fact, may be defined as the production of new organic forms from others more or less unlike themselves ; so that all the present plants and animals are the descendants, through a long series of modifications or transform- ations, or both, of a limited number of an ancient simpler type. We must not suppose that this change has gone on as if things were simply mounting a ladder; the truth seems to be that we have to deal with a sort of tree with a common root and two main trunks representing animal and vegetable life ; each of these is divided into a few main branches, these into a multitude of branchlets, and these into smaller groups of twigs. : This new view represents to us the evolution of the sum of living beings; shows that all kinds of animals and plants have come into existence by the growth and modi- fication of primordial germs. Now I want just to say that this is no new idea, it is the demonstration which is new to us in our present century and generation ; we have really to go back to the seventeenth century, if indeed we must not go as far back as Aristotle, for the first germs of it; but with regard to the history, however, I have no time to deal with it. There are two or three points, however, to be considered in regard to this evolu- tion. The individual organic forms need not continuously advance ; all that is required is that there shall be a general advance—an advance like that of our modern civilisation—while some individual tribes or nations, as we know, stand still, or become even degenerate. With 104 NATURE this reservation ; the first forms were the simplest. It may be that as yet we know really very little of the dawn of geological history; that the fossiliferous rocks are nowhere near the real base. This conclusion has been derived by Prof. Poulton! from the complexity of the forms met with in them; still we find that we have not to deal with such a vast promiscuous association of plants and animals of lowest and highest organisation as we know to-day ; we deal relatively only with the simplest. The story both with regard to plants and animals is alike in this respect. Let me deal with the plants first. The first were aquatic—that is to say, they lived in and on the waters. So far as we know, the first plant life was akin to that of the algz which include our modern seaweed, moss- like plants followed them, and then ferns, and it is only very much later that the forms we know as seed plants with gaily coloured flowers living on the land made their appearance. The general trend of change amongst the plants has been in the direction of a land vegetation as opposed to one merely in or on the surface of the waters, and some present seaweeds exhibit the initial simplicity of plant-structure which characterised the beginning of vegetable life, while the seed plants I have mentioned are of comparatively late development ; but we still have our seaweed ; so that with all the change in some directions some forms like the earlier survive. After this explanation, relating to work in an apparently different direction, you will have no difficulty in under- standing the meaning I attach to the word “ evolution ” in relation to stars and the chemical elements which visibly exist in them, so far as the history of plant change is concerned ; but we are not limited to plant life. The same conceptions apply to animal life, and it is important for my subject that I should refer to that also. What do we find there? We are brought face to face with the same progression from simple to complex forms. This is best studied by a reference to the geological record Stratigraphical geology is neither more nor less than the anatomy of the earth,” and the history of the suc- cession of the formations is the history of a succession of such anatomies ; or corresponds with development as dis- tinct from generation. In stratigraphical geology, as can be gathered from any book on geology, we find the names of certain beds which contain certain different forms of animal and vegetable life. We begin with the Laurentian and Algonkian and then pass to the Cambrian, then to the Ordovician, the Silurian and Devonian, and so on through a long list of beds and geological strata until we come eventually to the Recent, that is to say, the condition of things which is going on nowadays on the surface of the earth. And if we prefer to map those many different beds into more generic groupings, we begin with the Primary or Paleozoic, we pass on to the Secondary or Mesozoic, and then we finally reach the Tertiary or Cainozoic. The deposition of these beds and of the animal life which has been going on continuously on the surface while those beds have been deposited gives us the various changes and developments which have taken place with regard to animal forms. It is worth while to go a little into details and to indicate the changes in these forms which have taken place, in the most general way. Beginning with the Lower Cambrian, we find that the animal forms were represented by Invertebrata such as Sponges, Corals, Echinoderms, Brachiopods, Mollusca, Crustacea and many early Trilobites ; not to mention true Fucoids and other lowly plant-remains. When we come tothe Silurian, we find a large accession of the above forms, especially of Corals, Crinoids, and Giant Crustaceans (such as Pterygotus) and armoured animals (Ostracodermi) with- out a lower jaw, or paired fins ; the beginnings of Verte- 1 Presidential Address, Section D, British Association Meeting at Liver- pool, 1896. 2 Huxley, Q. J. G. S., xxv. p. xliii. NO. 1544, VOL. 60] [JUNE 1, 1899 brate life, not yet fully evolved, and one lowly organised group of armoured fishes named Cyathaspzs (without bone cells in their shelly-shield). Here, too, we meet with the first Air-breathers ; the wing of a Cockroach, and several entire and undoubted Scorpions! Thus in addition we get vertebrates as opposed to invertebrates, and the first traces of the fishes. In the advance to the Devonian the fishes (associated with giant Crustacea) pre- dominate; it has been called the age of fishes. In the next series, the Carboniferous, we find the first certain traces of amphibians, of which the early existence is like that of a fish: a state of things illustrated by the frog, which the majority of us in our early days have, 1 am sure, studied as a tadpole inits early stages ; and some of these amphibians still retain fish-like characters. It is not until we arrive at the Permian that the true reptiles are met with, but in the next great series, the Triassic, we meet with a remarkable evolutionary group of Reptiles, the Theriodontia, or beast-toothed animals, because (unique among reptiles) they possess a dentition like a dog or a lion, with incisors, canines and cheek-teeth ; the precursors doubtless of the succeeding Mammalian type. We pass easily thus from the reptiles to mammals which are related to them; for instance, the ornitho- rhynchus and the echidna are both Australian mammals which bring forth their young within the egg as do the reptiles. Well, after that we begin to deal with birds. The early birds were strikingly reptilian in some of their characters ; and the pterodactyle, which many of you may have seen remains of in different museums, was really a winged reptile and not a bird. From that we gather that mammals and birds are variants of reptiles. When we progress from the Jurassic to the Recent, we find man making his appearance as a direct descendant of all those early forms. ‘There is not much new in this. This, as I have said, is what Huxley largely demonstrated in this theatre thirty-nine years ago ina previous course of these Lectures to Working Men. When we come to study the life-history of the various forms brought before us by the geological strata, we find it to vary considerably, a fact indicated by the presence or absence of the different genera in the various strata. We find that the trilobites, for instance, only appear in the very early geological formations ; there is no trace of them in the recent, but if we take the annelids we find that they are continuous from the earliest to the latest formations ; we still have our worms. Again we find that certain other organic forms made their appearance very low down in the time scale, forms which were not represented at all in the earlier Cambrian and Silurian, and that some of these are continuous to the present day. Let us take the story of the fishes. A great many fishes made their appearance at the Devonian stage, there were few in the Silurian; some of these stopped there, whereas others have been continued from the Devonian times to our own. ‘Take, for instance, the Australian mudfish Ceratodus; to judge from the teeth this fish might well have lived on unchanged from late Paleeozoic times until the present day! We see there is a tremendous variation of possible life-range, so to speak, with regard to these different forms, and the plant record, although necessarily more imperfect than the animal on account of the nature of the organism, tells the same story in its fragmentary evidence. In that way, then, the geologist has been able to bring before us the continuity of life in various forms from the most ancient geological strata to the most recent. The record may be incomplete, but is complete enough for my purpose. But that is not the only evidence of evolution to which I can refer. The teachings of embryology confirm the argument based upon the study of geology, and suggest that the life-history of the earth is reproduced in the life-history of individuals. The processes of organic growth or em- June 1, 1899] NARORE 105 bryonic development present a remarkable uniformity throughout the whole of the zoological series; and although knowledge is still limited, some authorities hold that there is the closest possible connection between the development of the individual and the development of the whole series of animal life. There are others, how- ever, who do not regard the argument derived from embryology as a very convincing one. However this may be, if we study the embryos of the tortoise, fowl, dog and man, we find that there is a wonderful similarity between them ata certainstage. Ata further stage of development the similarity is still borne out. This does not mean that a vertebrate animal during its development first of all becomes a tortoise, and then the various animals which are represented by these embryos; it simply means that they are all related inasmuch as there is continuity. After these references to plants and animals it should be clear what organic evolution really is, and therefore what evolution is generally. I wish next to bring before you some considerations having relation to the strati- graphical record. The question for us now is—Is there any equivalent to this in the inorganic world? or, to put it in another way, in those facts which have been revealed to us by the presence of the various chemical forms in the stellar strata represented by stars of varying temperatures? That is the question. When I referred in my last course of Lectures here to cosmical evolution, I said that there we dealt with a continuity of effects accompanied by considerable changes of temperature; from the gradual coming together of meteoritic swarms until eventually we had a mass of matter cold and dark in space. The various stars which represent the different changes have been got out and have, in fact, been arranged along a so-called temperature curve. As we ascend one branch of this curve the stars get gradually hotter and hotter till ultimately at the top we find the hottest stars that we know of. Then on the descending branch are represented the cooling bodies, and finally they come down in temperature until we reach that of a dark world like the companion of Sirius, of our own moon, and the planet in which we dwell. We can now deal with all these bodies in relation to their chemistry. We find that in the hottest stars we get a very small number of chemical elements ; as we come down from the hottest star to the cooler ones the number of spectral lines increases, and with the number of lines of course the number of chemical elements. I will only refer to the known substances, it looks as if at present we have still many unknowns to battle with. In the hottest stars of all, we deal with a form of hydrogen which we do not know anything about here (but which we suppose to be due to the presence of a very high temperature), hydro- gen as we know it, the cleveite gases, and magnesium and calcium in forms which are difficult to get here ; we think we get them by using the highest temperatures available in our laboratories. In the stars of the next lower temperature we find the existence of these things continued in addition to the introduction of oxygen, nitrogen and carbon. In the next cooler stars we get silicium added; in the next we get the forms of iron, titanium, copper and manganese which we can produce at the very highest temperatures in our laboratories; and it is only when we come to stars much cooler that we find the ordinary indications of iron, calcium and manganese and other metals. All these, therefore, seem to be forms produced by the running down of temperature. As certain new forms are introduced at each stage, so certain old forms disappear. In order to connect this work with the stratigraphical work, to which I have referred, I have recently tried to define these various star-stages by means NO. 1544, VOL. 60] of their chemical forms which they reveal to us; so that we may treat these stellar strata, so to speak, as the equivalent of the geological strata to which I have already called your attention. From the hottest to the coldest stars I have found ten groups so distinct from each other chemically that they require to be dealt with separately as completely as do the Cambrian and the Silurian formations. Imitating the geologist, I have given the following names to these groups or genera beginning with the hottest, that is the oldest dealing with the running down of temperature :— Argonian, Alnitamian, Achernian, Algolian, Markabian [a “break in strata”], Sirian, Procyonian, Arcturian (solar), Piscian. I have gone further, and defined the chemical nature of these stellar genera as the biologist defines the nature of any of his organic genera ; we can say, for instance, that the Achernian stars contain chiefly hydrogen, nitrogen, oxygen and carbon, and to a certain less extent they contain proto-magnesium, proto-calcium, silicium and sodium,! and possibly chlorine and lithium ; so that at last, by means of this recent development of spectrum analysis, we have been able really to do for the various stars what the biologist a good many years ago did for the geological strata. Now, considering this inorganic evolution from the chemical point of view, there are several matters which merit consideration. We shall not get much help by thinking along several obvious lines, for the reason that in the stars we are dealing with transcendental tem- peratures ; for instance, we must not make too much of the difference between gases and solids, because, at high temperatures all the chemical elements known to us as solids are just as gaseous as the gases themselves ; that is to say, they exist as gases; at a high temperature, everything, of course, will put on the nature of gas. Those substances with the lowest melting points, such as lithium and sodium, will, of course, under our present conditions put on the gaseous condition very much more readily than other substances like iron and platinum, but those are considerations which need not be taken into account in relation to very high stellar temperatures ; of course, there would be no solids at a temperature of 10,000" C. Then with regard to metals and non-metals. Here again we really are not greatly helped by this distinc- tion. The general conception of a metal is that it is a solid, and that therefore a thing that is not a solid is not a metal; but the chemical evidence for the metallic nature of hydrogen has been enlarged upon by several very distinguished chemists. With regard to non- metals, there are certainly very many. Carbon is sup- posed to be a non-metal, and it is remarkable that, so far as the stellar evidence which I have brought before you has gone, carbon seems to be the only certain representative of that group. I want to point out specially that the table of the chemical definitions of the various stellar genera which I show you, which contains nothing but hard facts, is perhaps, like the geological record, more important on account of what it indicates as to the presence of the chemical elements in the stars than it is for what it omits. There are a great many reasons why some of the substances which may exist in these stars should not make their appearance. I wish to enlarge upon the fact that, seeing the very small range of our photo- graphs of stellar spectra, and seeing that it does not at all follow that the particular crucial lines of the various chemical substances will reveal themselves in that particular part of the spectrum which we can photo- graph, that the negative evidence is of very much less importance than the positive evidence. I think it is very likely, for instance, that we must add lithium to 1 Campbell, ‘* Astronomy and Astro-physics,” 1894, Xili. p- 395. 106 NATURE [JuNE 1, 1899 the substances which we find in the table, we must certainly add sodium, and also aluminium, and chlorine possibly, but about sulphur at present I have no certain knowledge; you will see the reason for these references later on. At all events, we can with the greatest confidence point out the remarkable absence of substances of high atomic weights, and the extra- ordinary thing that the metals magnesium and calcium undoubtedly began their existence in the hottest stars long before, apparently, there is any obvious trace of many of the other metals which a chemist would certainly have been looking out for. In relation to this new work, the first point to make is that the chemical forms we see in the hottest stars are amongst the simplest. What is the justification for this statement? Well, there are two reasons. The chemist will acknowledge that if there be such a thing as chemical evolution, an element of low atomic weight is simpler, that is, less massive, than an element of high atomic weight. If we rely upon spectrum analysis we can say, when dealing with the question of “series,” about which I hope to say something in my next lecture, that the elements which have the smallest number of “series” are in all probability simpler than those which have a large number, and this is still truer when we find that all the lines in the spectrum of a substance can be included in those rhythmical series, as happens in the case of the cleveite gases. So that the first stage of inorganic evolution, if there has been such an evolution, is certainly a stage of simplest forms as in organic evolution. The next point is that the astronomical record, studied from the evolution point of view, is in other ways on all- fours with the geological record. We get the same changes of forms, I may say that we get the sudden breaks in forms, disappearances of old accompanied by appearances of new forms, and with this we get, whether we consider the atomic weight point of view or the series point of view, a growth of complexity. The geological story is exactly reproduced. Now, here it is obvious that a very important point comes in. In inorganic evolution we are dealing with a great running down of temperature ; how tremendous, no man can say. We know the temperature of our earth, but we do not know, and we cannot define, the temperatures of the hottest stars. So that how great the temperature of the earth may once have been, supposing it to be repre- sented by the present temperature of the hottest star, no man knows anything with certainty. With regard to organic evolution, however, which has to do with the plant world and the animal world, there can have been no such running down of temperature at all. The temperature must have been practically constant. Please bear that in mind, because I shall have to refer to it later on. It is proper that I should say that just as the work of Darwin in the nineteenth century was foreshadowed by seventeenth century suggestions, so the stellar demon- stration which I have brought before you to-night has been preceded by hypotheses distinctly in the same direction. The first stage of chemistry, as you know, was alchemy. Alchemy concerned itself with trans- mutations, but it was found very early that the real function of the later science of chemistry was to study simplifications, and, of course, to do this to the utmost we want precisely those enormous differences in tem- perature which it appears the stars alone place at our disposal. With regard to the general question of inorganic evolution, the first idea was thrown out in the year 1815 by Prout, who, in consequence of the low atomic weight of hydrogen, suggested that that gas was really the primary element, and that all the others, defined by their different atomic weights, were really aggregations of hydrogen, the complexity of the aggregation being NO. 1544, VOL. 60] determined by the atomic weight; that is to say, the element with an atomic weight of twenty contained twenty hydrogen units ; with an atomic weight of forty it contained forty, and so on. The reply to that was that very minute work showed that the chemical elements, when they were properly purified and examined with the greatest care, did not give exactly whole numbers re- presenting their atomic weights. They were so and so plus a decimal, which might be very near the zero point, or half-way between, and that was supposed to be a crushing answer to Prout’s view. The next view, which included the same idea—that is to say, a physical con- nection between these different things as opposed to the view that they were manufactured articles, special creations, each without any relation whatever to the other, was suggested by Débereiner in 1817, and the idea was expanded by Pettenkoferin 1850. Both pointed out that there were groups of three elements, such as lithium, sodium, and potassium, numerically connected ; that is, their atomic weights being 7, 23, and 39, the central atomic weight was exactly the mean of the other two, 7 + 39 = 46, divided by 2, we get 23. Another way, however, of showing that is that 7 + 16 = 23, and 23 + 16 = 39; the latter method suggests a possible addition of something with an atomic weight of 16, In 1862 de Chancourtois came to the conclusion that the relations between the properties of the various chemical elements were really simple geometrical relations. That, you see, is a much broader view. It is not till 1864 that we come to the so-called “ periodic law,” which was first suggested by Newlands, and elaborated by Mendeléeff in 1869. According to this law, the chemical and physical properties of the elements are periodic functions of their atomic weights. Lothar Meyer afterwards went into this matter, and obtained some very interesting results from the point of view of atomic volumes. He showed that if we plot the atomic volumes of the different ele- ments, arranged according to their atomic weights from left to right, there is a certain periodicity in the apices of the curve indicating the highest atomic volumes. So far there was no reference to the action of tem- perature in relation to this, but in 1873 I suggested that we must have a fall of temperature in stars, and that the greater complexity in the spectra of certain stars was probably due to this fall of temperature. This idea was ultimately utilised by Sir William Crookes in an interesting variation of the periodic law, in which he assumes that temperature plays a part in bringing about the changes in the characters of the elements. Brodie, in 1880, came to the conclusion that the elements were certainly not elementary, because in what he called a “chemical calculus” he had to assume that certain sub- stances, supposed to be elements, were really not so ; and he then threw out the very pregnant idea that possibly in some of the hotter stars some of these elements which he predicted might be found. Nine years afterwards, Ryd- berg, one of the most industrious investigators of the question of “series” to which I have referred, stated that most of the phenomena of series could be explained by supposing that hydrogen was really the initial element, and that the other substances were really compounds of hydrogen ; so that you observe he came back to Prout’s first view in 1815. All these ideas imply a continuous action, and suggest that there was some original stuff which was continuously formed into something more complex as time went on. That is to say, that the existence of our chemical elements as we know them does not depend upon their having been separately manufactured, but that they are the result of the working of a general law, as in the case of plants and animals. You see at once that the stellar facts which have already been brought before you are entirely in harmony with the highest chemical thought, and indeed establish JUNE 1, 1899] NATURE 107 the correctness of its major contention. We may be said to pass from chemical speculation to a solid chain of facts, which doubtless will be strengthened and lengthened as time goes on. In all these changes we seem to be in the presence of a series of what chemists call polymerisations, that is, roughly, a series of doublings. The greater complexities may also have been brought about by the union of different substances. In either case, as temperature is reduced, we get a possibility of combinations which was not present before ; so that more and more complex forms are produced. That brings us to a possibility of considering the pro- cesses of inorganic evolution in relation to those of organic evolution. I have already referred to the fundamental difference in the conditions. We had a running down of temperature which no one could define in the case of the stars ; in the case of the organic evolution going on under our present conditions, we cannot be very much removed from the temperature conditions of the Cambrian form- ations. That isa point which I have made before, and it is important to insist upon it; clearly there cannot have been any very great change of temperature during the whole cycle of organic life. Previous to it we have found complexity brought about by doublings and com- binations, the result being, as I have already mentioned, more complex forms. Of course, at the dawn of organic life on the surface of the earth there may have been residua of the earlier chemical forms; that is to say, not all the elements which we found in the hottest stars had combined to form the substances of which the earth was composed. However this may be, the work of organic evolution, unlike that of inorganic evolu- tion, must have been done under widely different temperature conditions, but the result has been the same ; it has since provided us with another succession of forms getting more complex as time has gone on, and there is still a residuum of early forms. We are led then to the conclusion that life in its various forms on this planet, now acknowledged to be the work of evolution, was an appendix, as it were, to the work of inorganic evolution carried on in a perfectly different way. Although the way was different, still nature is so parsi- monious in her methods—she never does a thing in two ways that can be as well done in one—that I have no doubt that when these matters come to be considered, as they are bound to be considered with the progress of our knowledge, we shall find a great number of parallels ; but I am not looking for these parallels now. What I wish to drive at is a chemical point of view which I think of some importance in relation to what has gone before ; it is a point which I wish to make depending upon the existence of those elements which make their appearance in the hottest stars. In inorganic forms, in those repre- sented to us in the hottest stars and the stars of gradually lower temperature, we have forms produced by a junction of like or unlike forms. Very good; but the more of these junctions the more the early forms must have dis- appeared, unless we’ may take it that they may have been made occasionally to reappear by the destruction of the later forms: that is a point to bear in mind. If the simpler forms must go on doubling to provide the more advanced forms, then if all the simpler forms are so used up there will be none left, and the only chance of getting the simpler forms again is to destroy something which had been previously made ; and we can quite understand, of course, that there were many conditions of this dis- truction possible at the time when the crust of the earth was being formed. But however that may be, the gaseous elements with the non-gaseous elements first formed, would be the chief chemical substances on the surface and over it. Now the substances over the crust, of course, would be the gases, oxygen, hydrogen, nitrogen, and from the stars we can suggest carbon combined withthem ; that is to say, hydrocarbons, carbonic acid, and NO. 1544, VOL. 60] so on. On the surface, whether the surface be one of land or water, we should expect, in addition to the low melting point metals lithium and sodium, those two metals which we know existed in the hottest stars long before the others, magnesium and calcium. I have told you that lithium probably and sodium certainly exist in some of the relatively hot stars ; the evidence also suggests sulphur, and this is rendered more probable because of the sim- plicity of its spectrum-series. Now these are very remark- able associations, and seem far away from ordinary chemical considerations, but they are the most important substances in sea water. Constituents of Sea Water. Chloride of sodium i 77°75 55 magnesium 10°87 Sulphate of “5 4°73 a lime... 3°60 s potash ... 2°46 Bromide of magnesium 0°21 Carbonate of lime ... 0°34 The most easily thinkable evolution under these cir- cumstances would be that of organisms built up of these chemical forms, chiefly because they would represent the more mobile or the more plastic materials. You would not expect evolution to have begun in iron, you would have expected it to have begun in some- thing which was the most mobile and the most plastic. The available matter then for this evolu- tion would be those gases plus those metals and those non-metals to which I have referred. Now, mark this. Suppose you have this evolution ; if the forms so com- posed were to be multiplied indefinitely, the available material would be used up and organic evolution would be brought just as certainly to a dead-lock as the in- organic evolution was brought to a dead-lock when there was no possibility of any considerable reduction of temperature. We should expect a tendency to growth among the organic molecules, I dare not call it an inherited tendency, but I feel almost inclined to do so, having the growth of crystals in mind. Now, suppose that after you have got these new organic forms, the results instead of being stable were emphatically unstable, and still better, suppose you could induce a dissolution or the destruction of parts or wholes, progress would always continue to be possible, and indeed it might be accelerated.? The new organic molecules would ultimately not have the first user of the chemical forms left available by the inorganic evolution, but they would have the user of the gases and other substances produced by the dissolution of their predecessors. They would be shoddy chemical forms, it is true, but shoddy forms would be better than none. Under these circumstances and in this way, the organic kingdom would be allowed to go on ; in other words, the dissolution of parts or wholes of the néw organisms would not merely be an advantage to the race, but might even be an essential condition for its con- tinuance. It therefore looks very much as if we can really go 1 My friend and colleague, Prof. Howes, has called my attention in this connection to Prof. Weismann’s views (‘‘ Weismann on Heredity,” vol. i. . 112), who seems to have arrived at somewhat similar conclusions, though by a vastly different road. He says, in his “ Essay on Life and Death, “In my opinion life became limited in its duration not because it was con- trary to its very nature to be unlimited, but because an unlimited persistence of the individual would be a luxury without a purpose.” The general view I have put forward, however, suggests that perhaps it was not so much a question of /wxrury for the living as one of necessity in order that others might live ; it was a case of mors anua vitae. The whole question turns upon the presence or absence, in all regions, ot an excess of the early chemical forms ready to be used up 77 a@d/ necessary proportions. Hence it may turn out that the difficulty was much greater for land- than for sea-forms, that is, that dissolution of parts or wholes of land-forms proceeded with the greater rapidity. It is a question of the possibility of continuous assimilation (see Dantec, “ La Sexualité,” p. 11), and the word “ parts” which I have used refers to the somatic cells, and not to the “‘immortal’” part of living organisms. 108 NATURE [JUNE 1, 1899 back as far as these very early stages of life on our planet to apply those lines of Tennyson :— “ So Careful of the type she seems, So careless of the single life.” We have arrived, then, at a condition in which the same material may be worked up over and over again; in this way ultimately higher forms might be produced. Now, if to this dissolution, as a means of giving us new material, we add reproduction, then we can go a stage very much further. If we take bi-partition, which was the first method of multiplication, as we know both in the vegetable and animal world, we have a multiplication of forms by halving instead of the inorganic multiplication of forms by doubling, then we can have a very much increased rate of advance. These then, roughly, are the conclusions as to an organic evolution which are suggested by the stellar evidence as to inorganic evolution, and the collocation of the simplest forms noted in the hottest stars. Let us turn finally to the facts. Biologists, as I have said before, are very much more happy than astronomers and chemists, because they can see their units. A chemist professes to believe in nothing which he does not get in a bottle, although I have never yet seen the chemist who was ever happy enough to bottle an atom or a molecule as such; but the superstition still remains with them, and they profess to believe in nothing that they cannot see. Now, the organic cell is the unit of the biologist, which is itself a congeries of subordinate entities, as a molecule is made up of its elementary atoms, manifesting the properties common to living matter in all its forms. The characteristic general feature of the vegetable activity of the plant forms is their feeding upon gases and liquids, including sea-water. The progress of research greatly strengthens the view that there was a common life plasm, out of which both the vegetable and the animal kingdoms have developed. Be that as it may, you see the vegetable grows upon these chemical forms to which I have referred, and the animal feeds either upon the plant or upon other animals which have in their turn fed upon plants ; so that there we get the real chemical structure of the protoplasm, of the real life unit, in our organic evolution, The last question, then, that I have to touch upon is this. Is there any chemical relation between the chem- ical composition of the organic cell and the reversing layers of the hottest stars—the reversing layer being that part of a star’s anatomy by which we define the different genera? When we come to consider the chemical composition of this cell we find it consists of one or more forms of a complex compound of carbon, hydrogen, oxygen, nitrogen, with water, called protein; and protoplasm, of which you have all heard, the common basis of vegetable and animal life, is thus composed. This substance is liable to waste and disintegration by oxidation, and there may be a concomitant reintegration of it by the assimilation of new matter. The marvellous molecular complexity of the so-called simple cell may be gathered from the following formule for haemoglobin : Man... C600 H 960 Horse ... C 712 Nes4y Hemeas 3) .Olr79 Hiro N2tq Fer S2 © 245.1 Various different percentage compositions have been given of this protoplasm, but I really need not refer you to them. It 1s more important to consider the other chemical substances which go to form it, for there are others beside which it is of interest to study from our stellar point of view. I quote from Mr. Sheridan Lea.? i ee “ Verworn,” p- 104 “The Chemical Bas of the Animal Body,” p. 5. NO. 1544, VOL. 60] “Proteids ordinarily leave on ignition a variable quantity of ash. In the case of egg-albumin the prin- cipal constituents of the ash are CHLORIDES of SODIUM and potassium, the latter exceeding the former in amount. The remainder consists of SODIUM and potassium, in combination with phosphoric, sulphuric and CARBONIC acids, and very small quantities of CALCIUM, MAG- NESIUM and iron, in union with the same acids. There may be also a trace of SILICA.” My point is that the more one inquires into the chemistry of these things the more we come back to our stellar point of view and to the fact that, taking the simplicity of chemical form as determined by the appear- ance of these different chemical substances in the hottest stars as opposed to the cooler ones, and in relation to the “series” of spectra which they produce, we come to the conclusion that the first organic life was an inter- action somehow or other between the undoubted earliest chemical forms. Not only have we hydrogen, oxygen and nitrogen among the gases common to the organic cell and the hottest stars, but those substances in addition which I have indicated by capitals. Surely we have here, I think, thanks to some of the recent advances made by spectrum analysis, a quite new bond between man and the stars. We shall consider in the next lecture the simplicity of chemical forms as evidenced, not by atomic weight, but by the study of spectrum-series, to which I have already made two or three references. THE BERLIN TUBERCULOSIS CONGRESS (1899). = Congress, which has just brought its niotecames to a close, was not, as has been frequently stated in the medical and lay press, an International Congress ; it was a German Congress to which foreign delegates and comimunications were invited. The mass of communi- cations were made in German, this being the official language of the Congress; a few, some half-dozen, in English and French. The necessity, or at any rate ad- visability, of discoursing in German, may account for the very meagre manner in which English medicine was re- presented either privately or officially. It seemed some- what anomalous that the staff of only one London con sumption hospital (the North London) was represented at the Congress. Further, the English doctors practising at foreign health resorts, who probably have unrivalled opportunities for observing the different phases of con- sumption, and the influence of treatment upon them amongst better class patients, were for the most part conspicuous by their absence. This nonchalance is to be regretted, especially as the hygienic treatment of phthisis, a relatively, at any rate in its systematic form, new development; occupied some 50 per cent. of the whole time of the Congress. The enormous amount of material at the disposal of the Committee was classified in two ways. All papers were in the first instance denominated as lectures (“ Re- ferate ”), or discussion communications. For the former twenty minutes was allowed, for the latter ten. The subject-matter was divided into five Sections. I. Extent and Spread of Tuberculosis. II. Aetiology. III. Pro- phylaxis. IV. Treatment. V. Sanatorium Treatment. Section I.—Dr. Bollingen (Munich) read a paper upon tuberculosis amongst domestic animals, and its relation- ship to tubercular disease in man. Amongst many 1m- portant points, the lecturer emphasised the importance of milk as a source of tubercular infection to men, directly and indirectly. Indirectly in the sense that tuberculosis is very common amongst pigs, who get infected in con- siderable numbers from being fed with the milk of tuber- culous cows. Dr. Krieger (Strassburg) discussed the re- June 1, 1899] NATURE 109 lationship of external surroundings to the spread of tubercular disease. The author pointed out the un- satisfactory nature of statistics upon this subject, owing to the complexity of apparently simple factors. Constant attendance upon phthisical patients in badly ventilated rooms, and certain occupations giving rise to irritation of respiratory tract from dust, metallic or otherwise, were however, according to the lecturer, potent factors in the spread of tuberculosis. Papers followed upon tuber- cular disease among various employés, notably knife and sword makers, bookbinders, compositors, and cigar makers. Section II.—Aetiology.—This Section was opened by Prof. Fliigge (Breslau), who read a well-appreciated paper upon the relation of the tubercle bacillus to tuber- culosis. Recent work has not in this connection modified to any extent the dicta originally enunciated by Koch. The tubercle bacillus is the immediate cause of tuber- culosis, and arises in practically all cases from a tuberculous animal. Its parasitic nature is obligatory, g.e. except in the case of artificial cultures the bacillus cannot develop outside the animal organism. By means of artificial cultures it is possible to modify the tubercle bacillus in certain ways, notably with regard to its morphological character, and its virulence. Prof. C. Frankel (Halle) discoursed eloquently upon the nature and #odus operandi of tubercular infection. He pointed out that outside the animal body tubercle bacilli die in from six to seven months, the important factors in killing them being light, and the fact that they lose their water by evaporation, and with it their life. As a result of this it is, as a rule, only the immediate neighbourhood of the patient, from 1 to 1} metre, that is infective.. Infection usually takes place through the in- fected person inhaling freshand moist tubercle bacilli which (“infected drops”) have been ejected usually during a coughing fit, also by the inhalation of dust contaminated with dried sputum. He further pointed out that man was relatively unsusceptible to tubercular infection, and that, as a rule, it was only by repeated and continued inhalation, &c., of tubercle bacilli that infection occurred. A subject of great interest to physicians was considered at some length by Prof. Pfeiffer (Berlin), viz. “mixed infection.” Consumption, as we know it, is rarely due simply to the tubercle bacillus, but to the superadded action of other infective organisms. As many as twenty- four different varieties of bacilli have been obtained from the sputum. of a phthisical patient. An important practical point brought out by the lecturer was that cases of mixed infection ought to be recognised in con- sumptive hospitals, and isolated, as they may bea source of danger to phthisical patients ; that is, these latter may get a mixed infection superadded to their other troubles. Prof. Loffler read ashort paper upon heredity, immunity and disposition in their relation to tuberculosis. Here- ditary tuberculosis in the sense, for instance, of congenital syphilis, is unknown. In this disease hereditary influences probably play a relatively small part as such. Tuber- culosis occurs in members of the same family, mostly because by living together the members infect each other. Prof. Loffler quoted one family as an instance of this. The father and mother, two daughters and seven sons, all died of phthisis. The family consisted of fifty-eight other members, not one of whom was tuberculous. The infection was entirely confined to the members of the family living together. The lecturer emphasised the fact that no natural immunity to tuber- culosis exists. Dr. von Zander gave some aetiological Statistics of tuberculosis. Out of 312 cases investigated, 116 were communicated from man to man; amongst these infection between sisters occurred the most often. ' Section III.—Prophylaxis.—Dr. Roth (Potsdam) dis- cussed certain rules for the prevention of tubercular infec- NO. 1544, VOL. 60] tion. These mostly consisted of measures directed to the disposal of the sputum, and the use of a cloth in front of the mouth during coughing fits, to limit the area of “infective drop ” dispersion. Prof. vy. Leube (Wurzburg) considered the prophylactive methods against tuberculosis in hospitals. If measures such as those mentioned above are thoroughly carried out, tubercular patients need not be isolated from the general hospital inmates. Care should be taken by attendants and nurses especially in dusting rooms, when it would be advisable for them to have their mouth and nose protected by a mask. All members of the Congress listened most attentively to a short paper, by Prof. Virchow, upon the prevention of tuberculosis in so far as concerns food. Prof. Virchow considered four articles of diet: (1) beef, (2) pork, (3) poultry, (4) milk. Of these he regarded milk as far the most important. He advised a more careful and systematic exclusion (under central control) of tubercular meat and cattle, and the rejection of milk from all cows which reacted to the tuberculin list. Even these measures the author described as palliative, the only curative measure being the killing of all animals that reacted to the tubercular list. In this connection, Dr. Schumburg (Hannover) gave the result of his researches as to whether ordinary butcher’s meat contained tubercle bacilli. The result of twenty-four inoculations (intra-peritoneal) of guinea-pigs with the juice of twelve different meat samples, was that two animals died of purulent peritonitis, two greatly diminished in weight, the remaining twenty remained well. Dr. Baer (Berlin) discussed the much- vexed question of alcohol and tuberculosis. He concludes, upon apparently very insufficient grounds, that alcohol in the consumptive sanatoria should only be used as medicine under the most urgent circumstances. Dr. Ritter read a paper upon the protection of children from tuberculosis. An interesting communication upon the diminution in the total death-rate from consumption due to modern methods of treatment was made by Dr. Julius Lehmann (Copenhagen). Dr. Kuno Obermiiller discussed some interesting investigations upon the presence of the tubercle bacillus in ordinary market milk and butter. He centrifugalised the milk, and injected less than °5 cc. of the sediment into the peritoneal cavity of guinea- pigs. The milk was taken from a dairy which supplies Berlin with 80,000 litres daily. The result was that 30 per cent. of the injected animals died in from eleven to thirteen weeks of tuberculosis. The milk used was the best and most costly infant milk. According to the author, Berlin butter is also largely infected with virulent tubercle bacilli, which are quite distinct from the so-called butter bacillus. Dr. Hambleton, President of the Polytechnic Physical Development Society, was the author of a com- munication on the prevention of pulmonary tuberculosis. One of the most potent factors to this end is, according to the author, chest development, and he took this oppor- tunity of bringing before the notice of the Congress the work of the Society in this direction. This method had, according to the author, been most successful in pre- venting and even arresting tuberculosis among the employés of trades having an injurious effect upon the respiratory organs. F, W. TUNNICLIFFE: THE JUBILEE OF SIR’ GEORGE GABRIELE STOKES. A(uane celebrations in connection with the jubilee of Sir George Gabriel Stokes, who has occupied the Lucasian Chair of Mathematics at Cambridge University since 1849, begin this afternoon (Thursday) with the delivery by Prof. Cornu, of the Ecole Polytechnique, Paris, of the Rede Lecture. Prof. Cornu has chosen | as his subject, “The Wave Theory of Light and its Influence on Moder Physics.” I1O MAT OLE [JUNE 1, 1899 This evening a banquet will be given by Pembroke College, at which many of the distinguished guests and older colleagues of Sir George will be entertained in the hall of the College, which he entered as a freshman in 1837. During the evening the University will entertain about one thousand visitors and residents at a con- versazione in the Fitzwilliam Museum, an interesting feature of which will be the presentation by Lord Kelvin of two busts, executed by Mr. Hamo Thorneycroft, of Sir George Stokes—one to the University, and the other to Pembroke College. On Friday at Ir a.m., in the Senate House, the addresses of congratulation will be presented to the Vice-Chancellor, and handed by him to Sir George Stokes. Some sixty-five different institutions from all parts of the world will be represented. At 7 o’clock the delegates and their hosts will be entertained at luncheon by the Vice-Chancellor at Downing College, and at 2.45 a second congregation will be held in the Senate House, at which the Chancellor, the Duke of Devonshire, will preside. At this congregation, the honorary degree of Sc.D. will be conferred on Profs. A. Cornu and J. G. Darboux of Paris, on Prof. A. A. Michelson of Chicago, on Prof. M. G. Mittag-Leffler of Stockholm, on Prof. G. H. Quincke of Heidelberg, and on Prof. W. Voigt of Gottingen. A gold medal struck in honour of the occasion will be presented to Sir George Stokes by the Chancellor, and replicas will be sent to all the Uni- versities and learned societies who are represented at the Jubilee. Later in the afternoon a garden party will be held in the grounds of Pembroke College, and in the evening the University will entertain the delegates and guests at a dinner given in the hall of Trinity College. The Chancellor will take the chair, and amongst other dis- tinguished guests who have accepted invitations may be mentioned the Lord Lieutenant of Cambridgeshire, the Bishop of Ely, the President of the Royal Society, the Vice- Chancellors of the Universities of Oxford, Aberdeen, and London, the Earl of Rosse, Lord Kelvin, Lord Rayleigh, Lord Blythswood, the Provost of Trinity College, Dublin, Monsignor Molloy, and many others. There will be a special meeting of the Cambridge Philosophical Society, at which some of the foreign members will, it is expected, read papers. This will probably take place on Monday, June 5. Many of the guests will leave Cambridge for London to take part in the anniversary celebrations of the Royal Institution. NOTES. A MEETING for discussion will be held at the Royal Society on Thursday next, June 8. The subject to be discussed—pre- ventive inoculation—will be introduced by M. Haffkine. ARRANGEMENTS for the sixty-ninth annual meeting of the British Association at Dover, in September next, are making The local committees are actively at response to the appeal of the hospitality committees over 1500/7. has already been subscribed. As previously announced, the president of the meeting will be Prof. Michael Foster, and the pre- sidents of the various sections are to be :—Mathematical and physical science, Prof. J. H. Poynting ; chemistry, Mr. Horace T. Brown ; geology, Sir Archibald Geikie ; zoology, Mr. Adam Sedgwick ; geography, Sir John Murray, K.C.B. ; economical science, Mr. Henry Higgs; mechanical science, Sir William H. White ; anthropology, Mr. C. H. Read; physiology, Mr. J. N. Langley; botany, Sir George King, K.C.I.E. The first general meeting will be held at the Connaught Hall on Wednesday, September 13, at 8 p.m. precisely, when Prof. Michael Foster will deliver an address; on Thursday NO. 1544, VOL. 60] satisfactory progress. work, and in evening, September 14, at 8 30 p.m., there will be a soirée in the School of Art; on Friday evening, September 15, at 8.30 p.m., a discourse will be delivered by Prof. Charles Richet, on ‘‘La vibration nerveuse’’; on Monday evening, September 18, at 8.30 p.m., a discourse will be delivered by Prof. Fleming, F.R.S., on ‘‘The Centenary of the Electric Current”; on Tuesday evening, September 19, at 8.30 p.m., there will be a soirée in the School of Art; on Wednesday, September 20, the concluding general meeting will be held at 2.30 p.m. Excursions to places of interest in the neighbourhood of Dover and to the continent will be made on Thursday, September 21. Members of the Asso- ciation Frangaise pour l’Avancement des Sciences will visit Dover on Saturday, September 16. Members of the British Association are invited to visit Boulogne on Thursday, September 21. THE following naturalists have been elected foreign members of the Linnean Society :—M. Adrien Franchet of Paris, Prof. Emil Christian Hansen of Copenhagen, Dr. Seiitsiro Ikeno of the Imperial University, Tokyo; Prof. Eduard von Martens of Berlin, and Prof. Georg Ossian Sars of Christiania. THE gold medal of the Linnean Society, which was pre- sented at the anniversary meeting on May 24, has this year been awarded to Mr. John Gilbert Baker, of Kew, in recognition of his important contributions to botanical science. Amongst these may be mentioned his Syzopsis Filicum, his monographs of the daffodils and roses, handbooks on the Amarylideae, [rideae, Bromeliceae, and the fern allies; three volumes on the Com- posttae in Martins’s ‘‘ Flora Brasiliensis,”’ and several papers on Malagasy botany, the Flora of Mauritius and the Seychelles, the Bulbous Flora of the Cape, and the Zegumznosae of British India, ‘‘ Flora of the English Lake Country,” and numerous papers communicated to the /owrna/ of the Linnean Society, the Journal of Botany, and other periodicals. Ar the annual meeting of the Victoria Institute, to be held on June 19, an address will be delivered by Sir Richard Temple. THE anniversary meeting of the Royal Geographical Society will be held on Monday next, June 5. The Society’s annual conversazione will be held in the Natural History Museum on Wednesday, June 7. THERE will be no Friday evening discourse at the Royal Institution to-morrow (June 2), as Mr. H. G. Wells, who was to lecture on ‘‘ The Discovery of the Future,” is in too weak a state of health to do so, AT the recent annual meeting of the American Academy of Art and Sciences, Mr. Alexander Agassiz was elected president of the Academy. The Rumford medal was awarded to Mr. Charles F. Brush, of Cleveland, for ‘‘ the practical development of electrical arc lighting.” A REvTER telegram dated Helsingfors, May 26, says :— “©The collected pieces of the aérolite which fell at Bjurholm some time ago have been sent here, and placed in the geological museum. The largest piece is said to weigh 206 Russian pounds, while all the parts together weigh 850 Ibs.” Dr. L. A. BAUER has resigned his position as assistant professor of mathematics and mathematical physics at the University of Cincinnati, in order to accept the position of chief of the newly-formed division of terrestrial magnetism of the United States Coast and Geodetic Survey. To this division has been assigned the magnetic survey of the United States and the countries under its jurisdiction, and the establishment of magnetic observatories. Dr. Bauer has also been appointed lecturer in June 1, 1899] NATRORE Wen terrestrial magnetism at the Johns Hopkins University. The journal, Zerrestréal Magnetism and Atmospheric Electricity, beginning with the June number, will be issued hereafter from the Johns Hopkins University Press, Dr. Bauer continuing as editor-in-chief. ON the evening of May 13 a meeting of the New York Electrical Society was held at Madison Square Garden, where an Electrical Exhibition is now going on, to celebrate the cen- tennial of the discovery of the electric battery by Alessandro Volta. Mr. Edison sent a letter expressing his admiration of Volta’s investigations and researches, and associating himself with the fraternal messages which were sent to the Italian electrical society and to the Electrical Exhibition at Como, the birthplace of both Volta and the voltaic cell. The New York Electrical Review states the following message was cabled to the Italian Premier :—‘‘ The electricians of America, celebrating the Volta Centennial in New York, extend heartiest congratu- lations to the fellow-workers in Italy, and, in doing so, desire to express the hope that the work of such pioneers as Galvani, Volta, Pacinetti and Ferraris may be renewed and repeated by other members of the Italian race in the century which is now dawning. America owes a deep debt of gratitude to Italy for electrical discoveries, which have done so much to abridge dis- tance and add to the welfare of mankind. Please communicate these sentiments to King Humbert in the name of tne New York Electrical Society. —Gano S. Dunn, President.” THE Berlin correspondent of the 7zmes states that the com- mittee which is organising the German Antarctic expedition has decided that the expedition is to be composed of one ship only. The vessel, which is to be built entirely of wood, is to be laid down this autumn. The expedition is to be ready to start in the autumn of 1901, and is to be away two years altogether. After touching at the Cape, the expedition is to make for the Antarctic continent south of the Kerguelen Islands, and there establish a scientific station at some point suitable for wintering. A pack of Siberian dogs is to be taken, and dashes will be made on sledges towards the South Pole and the south magnetic pole. Meteorological observations will also be made from a captive balloon, After the breaking up of their winter quarters, the expedition will attempt to make as complete a survey as possible of the coast line of the Antarctic continent. As already announced in these columns, the leader of the expedition is to be Dr. von Drygalski, who conducted the German explor- ‘ation of Greenland in the years 1891-93. The committee expresses great satisfaction that the English Antarctic expedition has at last been definitely decided on, and points out that the value of the two sets of meteorological observations will be greatly enhanced by their being carried on simultaneously. AN Industrial Exhibition organised by the Artist Club was opened at the Crystal Palace on Tuesday by the Duke and Duchess of Connaught. The exhibition has been furnished by about one hundred leading British manufacturers, and the élement of competition has been eliminated by only including one set of exhibits of any particular industry. Engineering appliances of various kinds are prominent. Railway and steam- ship interests are also well represented. Refrigerating processes employed in the Colonial meat trade are shown in operation. There is also an interesting display of printing machinery at work, and of type-setting by Linotype machines. Electricity figures in the exhibition, and a number of novel devices of various kinds are to be seen. As an example of quick work in photography, it is worth mention that the opening ceremony was photographed and projected upon the screen by the Biograph and Mutoscope Company before the Royal party left the Crystal Palace three hours later. NO. 1544, VOL. 60] Art the annual general meeting of the Institution of Electrica] Engineers, held on Thursday last, the announcement was made that the premiums for papers read during the session 1898-99 had been awarded by the Council as follows :—The ‘‘ Institu- tion Premium,” value 257., to Mr. P. V. McMahon, for his paper on ‘Electric Locomotives in Practice, and Tractive Resistance in Tunnels, and Notes on Locomotive Design”; the ‘* Paris Electrical Exhibition Premium,’’ value raised to 20/., to Mr. W. Duddell and Mr. E. W. Marchant, for their paper, ‘Experiments on Alternate Current Arcs by aid of Oscillo- graphs” ; two ‘‘ Fahie Premiums,” none having been awarded in 1898, of 10/. each, one to Prof. O. Lodge, F.R.S., and one to Mr. G. Marconi, for their papers entitled respectively ‘‘ Im- provements in Magnetic Space Telegraphy”’ and ‘‘ Wireless Telegraphy ” ; two extra premiums of 10/7. each, one to Mrs. Ayrton for her paper on ‘‘ The Hissing of the Electric Arc,” the other to Mr. J. Elton Young, for his paper on ‘‘ Capacity Measurements of Long Submarine Cables’; the Senior “*Students’ Premium,” value ro/., to Mr. W. G. Royal- Dawson, student, for his paper on ‘‘ Alternating Currents of very High Frequency” ; the second ‘‘ Students’ Premium,” in- creased in value to toZ,, to Messrs. M. R. Gardner and W. P. Howgrave Graham, for their paper on ‘“‘ The Synchronising of Alteriators” ; the third ‘‘Students’ Premium,” value 5/., to Mr. Leonard Wilson, student, for his paper on ‘‘ The Effect of Governors on the Parallel Running of Alternators”; extra “« Students’ Premium,” value 4/,, to Mr. L. R. Morshead, for his paper on ‘‘ Enclosed Are Lamps,” and an extra ‘‘ Students’ Premium,” value 3/., to Mr. H. M. Dowsett, student, for his paper on ‘‘ Electricity Meters” ; the Salomons Scholarship for 1899-1900, value 50/7, was awarded to Mr. H. J. Thomson, a student of the Central Technical College. Tue hydrographical surveys made in H.M. surveying vessels during the year 1898, and referred to in the recent report by the Hydrographer of the Admiralty, led to a number of important results. Resurveys of parts of the Thames and Medway show that remarkable changes have taken place. An examination of the Shingles patch in the Duke of Edinburgh | Channel has shown that this patch now has 15 feet of water on it, and its steady growth since 1882 has reduced the width of the Duke of Edinburgh Channel, at present the principal passage into the Thames for heavy vessels, from 14 miles to about zamile. The total obliteration of the passage, which seems by no means impossible, would entail a long circuit at the time of low water to large vessels to or from the Thames and Med- way, but the operations of nature in this estuary are far too great to be controlled by works. A resurvey was made of the Middle Swin. This passage way, the main route for the enormous trade between London and the north, has of late years much contracted and shoaled, and gives considerable anxiety to the Trinity House, as, if necessary to alter the route, many changes in lights and buoys would be necessary to make another passage safe. There is now very little more than 19 feet on the bar at low water. A SERIES of observations with a deep-sea current meter, | carried out in the large Strait of Bab-el-Mandeb by the officers of H.M. surveying vessel Stor/:, are referred to by the Hydro- grapher in his report. The observations, which are valuable as bearing on the system of circulation in the oceans, have been published in a report on the under-currents of the Straits of Bab-el-Mandeb ; but the broad result may be briefly stated. | . - There was a permanent current on the surface setting z¢o the Red Sea of about 14 knotsan hour. There was at 105 fathoms depth a permanent current of about the same velocity setting outwards, The tidal stream was about 1} knots at its maxi- mum, and flowed for about twelve hours each way, as might ae? NATURE (JUNE 1, 1899 be expected from the fact that in this locality there is practically only one tide in the day. This tidal stream prevails to the bottom with variations of strength. Somewhere about 75 fathoms below the surface is the dividing line between the two permanent currents, but there were not sufficient observations to determine the exact depth with any precision. In the current number of the Psychological Review, Prof. Wesley Mills points out that in investigating the psychology of animals, care must be taken to observe them under conditions as nearly approaching their normal surroundings as possible. He maintains that to place a cat in a box, as has been done, and then to expect it to act naturally, is about as reasonable as to enclose a living man in a coffin, lower him, against his will, into the earth, and attempt to deduce normal psychology from his conduct. Besides, the highest animals should be compared with the lowest human beings before maintaining that there is an essential difference between the respective mental lives of animals and the human race. A SERIES of instructive experiments on young chicks have been made by Dr. Edward Thorndike. About sixty chicks of all ages were studied, and some remarkable instances of in- stinctive muscular coordination and emotional reaction were observed. A four days’ chick will jump down a distance eight times his own height without hurting himself. Thrown into a pond, he will make straight for the shore, while an adult hen would float about aimlessly. For the first four or five days there is no fear of strange objects or sounds, such as the sight of aman ora hawk’s cry. Instinct does not always lead to the same reaction. A loud sound may make one chick run, another crouch, another give the danger call, and another do nothing whatever. Av Montgomery, Alabama, the daily forecasts of the U.S. Weather Bureau are shown on all street letter-boxes. The postman who collects the letters also fixes the forecast cards in position, so that the morning predictions of weather become known throughout the city by about 1 p.m. of the date of issue. THE Mitteilungen aus den deutschen Schutzgebieten con- tains a valuable contribution to our knowledge of the Har- mattan winds in the form of three short papers by competent observers in Togoland, and a discussion of the material by Dr. von Danckelmann. The investigation leads to the conclusion that the Harmattan, strictly so called, is a strengthening of the general north to south movement of the atmosphere prevalent in the western Sudan between October and April, caused by special modifications in the distribution of pressure which are not yet fully explained. The excessive dryness of the air, and its dustiness, are due to the origin of the current in the regions north of the bend of the Niger ; and it is shown that the wind may penetrate into coast districts normally exposed to the in- fluence of the moist sea breeze. The characteristic low morning temperatures are probably due to excessive radiation, but the point requires further elucidation. WE have received the seventh annual report of the Sonnblick Society, for the year 1898, containing the meteorological observ- ations on the summit of the Sonnblick mountain, lat. 47° 3’ N., long. 12° 57’ E., altitude 10,191 feet, and also at two inter- mediate stations, respectively nearly 4000 and 3000 feet above the sea. The observations have been carried on with great care and regularity, and the observatory on the summit is now under the entire management of the Austrian Meteorological Society. The difficulty of carrying on the work of this important station may be gauged from the following results for the year. The mean annual temperature was 22°°3, the absolute maximum 46°°4, and the minimum minus 13°°7. Fog occurred on 250 NO. 1544, VOL. 60] days, and rain (or snow) on 200 days. The report also contains useful detailed information respecting the mineral products of the neighbourhood, and particulars relating to the high observ- atories in the Alps. Tue Central Physical Observatory of St. Petersburg has recently published its Azsals for the year 1897, consisting of two large quarto volumes. The first part contains the meteorological and magnetic observations made at the stations of the First Order, and the extraordinary observations at stations of the Second and Third Orders ; for several stations, observations are published for every hour. The second part contains the meteorological observations of the Second Order stations, arranged according to the international scheme, and gives the observations made three times a day, and results for eighty- two stations, and a 7éseé of the monthly and annual means for 661 stations. Each set of observations is preceded bya detailed introduction, giving particulars of the methods employed and of the instruments used. In accordance with the decision of the Meteorological Conference at Paris in 1896, a useful list is added of all the periodical publications appearing in Russia which contain meteorological observations. The Director of the Meteorological Service is General M. Rykatcheff, Member of the Imperial Academy of Sciences of St. Petersburg. Dr. KEILHACK contributes a short paper on the hydrography of north-western Germany to the Verhand/ungen of the Berlin Geographical Society. The relation of the later glacial deposits to the existing valleys and lakes is discussed, and a map shows the supposed successive positions of the inland ice, and the courses of the longitudinal valleys associated with each phase of its movement. WE have received No. 3 of the ‘‘ Current Papers” published by Mr. H.C. Russell in the Proceedings of the Royal Society of New South Wales, along with which is a chart showing the tracks of floats between September 1896 and September 1898. The additional information confirms the result stated in the second paper, that the rate of drift increases with latitude south of 30° S. One float gave an average rate of 12°4 miles per day in latitude 47°"16 S. CHARLES WACHSMUTH (of Burlington, Iowa), who died in 1896, had for forty years zealously studied the fossil Crinoidea of the older rocks of North America, being assisted during the latter half of the period by Mr. Frank Springer. The labours of the two on “The North American Crénoédea camerata” have been published in an important monograph containing 838 pp. and 83 plates; and this work has now been subjected to an elaborate criticism by Mr. F. A. Bather, of the British Museum (Natural History), who has reprinted his series of articles, which were published in the Geological Magazine (1898-99). These critical ‘essays form an important contribution to the study of the Crinoidea, and they are appropriately accompanied by a portrait and brief biography of Wachsmuth. Mr. ArNotpd HacGur, in his presidential address to the Geological Society of Washington (February 1899), took as his subject the ‘‘ Early Tertiary Volcanoes of the Absaroka Range.” This range extends along the east side of the Yellowstone Park, in the State of Wyoming, and several of the higher peaks and the long western spurs slope gradually towards the Park, and lie within its borders. The Absarokas present a high plateau, ranging from 10,000 to over 12,000 feet above sea-level, and composed of agglomerates, tuffs, and lava fiows, based upon Archzean and Palaeozoic rocks, and including masses of intrusive igneous rock, The volcanic materials constitute the bulk of the mountains, and they were ejected from numerous vents and fissures at several successive epochs, mainly in the following order : early acid breccia, early basic breccia, early basalt sheets, JuNE 1, 1899] INET RE late acid breccia, late basic breccia, and late basalt sheets. Evidence of the long duration of the period of volcanic activity is furnished by the remains of plants found at different horizons ; over 150 species having been identified, many of them new to science. In one instance, a grand old tree, Seguota magnifica, was found firmly imbedded in the early basic breccia. In Narure for March 9 we gave a short account of the late Prof. Cope’s researches on the Vertebrate remains from the Port Kennedy bone deposit in Pennsylvania. We have since received the detailed account of the excavations carried on in 1894-96 by Mr. Henry C. Mercer (Journ. Acad. Nat. Sc., Philadelphia, vol. xi. part 2, April 1899). The results lead to the conclusion that the original configuration of the fissure in which the remains were obtained was that of a deep, well-like chasm opening vertically downward from the sloping surface of a hill, and that the animals stampeded by a flood had rushed to their destruc- tion into the abyss. We have previously mentioned the principal fossil remains obtained. Of these, no less than 377 individuals and 66 species were recognised, of which latter 40 are extinct. No traces of man were discovered, and the general evidence favours the view that the fauna is of earlier date than that which witnessed the presence of man on the American continent. A RECORD of the work accomplished in the chemical labor- atory of the Austrian Geological Survey during the year 1898 is summarised in the Director’s Annual Report ( Verhandlungen der k. k. geol. Reichsanstalt, No. t, 1899). In addition to the petrographical examination of many rock-specimens, the official work comprised the analysis of no less than 203 samples, such as coals, rocks, ores, and waters. Additional researches, carried out for scientific purposes, are also recorded. Many samples of the materials employed in the construction of the new Danube embankments were examined and reported upon by Dr. v. John, who also concluded the analyses of various Bohemian mineral waters. The results of this last work are published in the September number of the /ahrduch, 1898. Of special economic value are Herr Aug. Rosiwal’s experiments for ascer- taining methods which shall furnish definite standards whereby all the factors of stability determining the technical utility of building stones may be accurately measured. Some interesting results attained in this connection have already appeared in the Verhandlungen, Nos. 5 and 6, 1808. WE have recently received from the publishers parts 38-40 of Prof. Enrico Morselli’s ‘* Antropologia Generale,” now in course of publication at Turin. As these fasciculi deal with the intricate problem of man’s evolution from the lower animals, they are of more than ordinary interest. The author has done wisely in reproducing a large number of the phylo- genetic trees published by modern zoologists, thus giving his readers an opportunity of seeing in what respects they agree or differ from one another. Manifestly, however, his sympathies are with Haeckel’s tree of mammals, in which, as is well known, the marsupials form an early offshoot from the main stem. As regards the anthropoids themselves, the author adopts Schlosser’s tree, in which a primitive gibbon (Prothy- fobates) is taken as a starting point, from which the gibbons rise as one branch, while Dryopethecus forms the main stem. This latter is continued directly upwards to give rise to the orang and chimpanzee, while on one side branches the gorilla, and on the other Pthecanthropus and Homo. The weak point of this is the wide separation of the chimpanzee and the gorilla. Apart from this, the gibbon-like character in the skull of Pithecanthropus (which can scarcely be regarded as generically distinct from Homa, unless mental characteristics be taken into account) affords considerable support to the general plan of the phylogeny. NO. 1544, VOL. 60] Two reprints from the Botanical Gazette have reached us, by Prof. C. J. Chamberlain and Prof. J. M. Coulter, both re- ferring to the phenomena of fertilisation and embryology in the Coniferee. THAT patient observer, Mr. Thomas Meehan, continues, in the Proceedings of the Academy of Natural Sciences of Phila- delphia, his contributions to the life-history of plants, mostly relating to the phenomena of fertilisation. THE most recently published part of Engler’s Botanische Jahrbticher, vol. xxvi. Heft 5, is chiefly occupied with the con- clusion of Kranzlin’s Orchidaceze of Guatemala and adjacent countries, and a further instalment of the editor's monograph of the Aracee. There are also revisions of the genera Ph2/odei- dyon, Dieffenbachia, and Tropaeolum. For the past ten years experiments have been carried on, on an extended scale, to test the suitability of the soil and climate of Indiana for the production of beet-sugar. The results of these experiments are now published in Azd/e¢zn No. 68 of the Purdue University Experiment Station (Lafayette, Ind.). They show that, wherever the needful precautions have been observed, beets of satisfactory character have been produced in every section of the State, and that it is probable that Indiana can produce enough beets. of satisfactory quality to furnish the raw material for a large number of factories. THE third part of Drs. D. S. Jordan and B. W. Evermann’s ‘The Fishes of North and Middle America,” being a descrip- tive catalogue of the species of fish-like vertebrates found in the waters of North America, north of the Isthmus of Panama, has been issued by the Smithsonian Institution as Az//etz No. 47 of the U.S. National Museum. Ir is a little surprising that Wiedemann and Ebert’s ‘© Physikalisches Practikum,” the fourth edition of which has just been published by Friedrich Vieweg and Son, Brunswick, has not been translated into English. The volume contains a well-arranged and complete course of laboratory work suit- able for students who are already familiar with elementary physical operations. Physical-chemical experiments receive particular attention. Mr. C. BAKER has issued a new catalogue of microscopes and accessory apparatus. Many instruments for histological and bacteriological work are included in the catalogue, and outfits suitable for various technical purposes. It is evident from the catalogue that, apart from the medical practitioner, naturalist and amateur, the microscope is being more and more used in trade and professional work. THIRTEEN important memoirs are published in the 4ééz of the Naples Academy of Physical and Mathematical Sciences (1899, ser. ii. vol. ix). Among the subjects dealt with are: remains of great Pleistocene lakes and rivers in southern Italy, with special reference to the geological conditions which produced such plains as the great Vallone di Diano (full descriptions, with maps, are given of the Agri, Mercure, and Noce) ; chemical analyses of the waters of the hot springs of Iscia ; contribution to the biology of ferns; flora of the basin of the Liri; and fossil fishes of the Eocene chalk of Gassino, Pied- mont. The remainder of the memoirs deal with mathematical and geometrical subjects. WirHour disparaging the Smithsonian Institution in the slightest degree, it may be said that the most valuable part of the Annual Report is the appendix, which comprises a selection of interesting memoirs upon scientific subjects. The report for 1897, just distributed, contains no less than thirty-eight memoirs of this kind, dealing with the position and progress of various It4 branches of science. The memoirs are ‘‘not for the specialist, but interesting and popular expositions of what the specialist knows to be sound and opportune.” A number of the memoirs are reprints of addresses and articles which have appeared in NATURE, some are original articles, and others are translations or reprints from contributions to various scientific publications. Almost every phase of scientific activity seems to be included among the papers, and many subjects are illustrated by fine half-tone pictures. The Smithsonian Institution does good service to science by the publication of these sound and in- structive surveys of the state of natural knowledge. THE additions to the Zoological Society’s Gardens during the past week include a Smooth-headed Capuchin (Ces monachus) from South-east Brazil, presented by Mr. Herbert Gibson; a Palm Squirrel (Sczurus palmarum) from India, presented by Miss Aggie O’Connor; a Kinkajou (Cercoleptes candivolvulus, 2 ) from South America, presented by Mr. J. J. Quelch ; a Mexican Guan (Ortalzs vetula) from Cartagena, Colombia, presented by Captain W. H. Milner; a Martinique Gallinule (/onornds martinicus), captured at sea, presented by Mr. H. O. Milner; a Leith’s Tortoise ( Zestudo /eithz) from Egypt, presented by Mr. S. S. Flower; a Black-tailed Wallaby (AZacropus walabatus, 9 ) from New South Wales, three Rabbit-eared Bandicoots (Pera- gale lagotts, 3 8), two Spotted Bower Birds (Chlamydodera maculata) from Australia, two Westermann’s Cassowaries (Casuarius westermannz) from New Guinea, a White-throated Monitor ( Varanus albigularis) from South Africa, two Starred Tortoises (Zestudo elegans) from India, four Elephantine Tortoises (Zestudo elephantina) from the Aldabra Islands, deposited. OUR ASTRONOMICAL COLUMN. ASTRONOMICAL OCCURRENCES IN JUNE :— June I. 14h. 53m. to 15h. gom. Occultation of the star 19 Piscium (mag. 5°2) by the moon. 7. 16h. 43m. to 17h. 53m. Partial eclipse of the sun visible at Greenwich. The greatest phase occurs at 17h. 17m., at which time o°188 (nearly one-fifth) of the sun’s disc will be obscured. At places N.W. of Greenwich the eclipse will be of somewhat greater magnitude. It. 2h. Saturn in opposition to the sun. 15. Illuminated portion of the disc of Venus o0*904, of Mars 0°913. 20. Ith. 3om. Minimum of the variable star Algol (B Persei). 22. 7h. Saturn in conjunction with the moon. 23. Sh. 19m. Minimum of the variable star Algol (B Persei). 23. 10h. 34m. to 11h. 41m. (mag. 5°8) by the moon. 24. 13h. 17m. to 14h. I2m. (mag. 5°1) by the moon. 25. 10h. 45m. torth. 48m. Occultation of B.A.C. 7145 (mag. 6'0) by the moon, 27. 12h. 59m. to 14h. 2m. (mag. 5°5) by the moon. 28, Ith. 22m. to 12h. rom. (mag. 5) by the moon. Occultation of B. A.C. 6343 Occultation of / Sagittarii Occultation of « Aquarii Occultation of « Piscium Comet 1899 a (SWIFT).— Ephemerts for 12h. Berlin Mean Time. 1899. R.A Decl. Br. Ee aitls aS. Ch ilecs June 1 17 58 35 + 50 13°1 2 17 36 8 55 138 1°34 3 17.15 28 54) yay 4 16 56 46 2 3972 1°18 5 16 39 54 5t 975 6 16 24 46 49 34°6 1'03 7) Se eG Tess 47 57°1 Site I5 59 12 + 46 1871 o'$8 NO. 1544, VOL. 60] NATURE [JUNE 1, 1899 The comet is now passing with a greatly accelerated motion in a south-westerly direction. During the week it will traverse the constellations Draco and Herculis; on the Ist it passes close to € Draconis, while on the 8th it will be a little more than 1° north-west of » Herculis. In Ast. Mach., No. 3567, Prof. A. A. Nijland, of Utrecht, says that, viewed with a finder of 74 mm, aperture on May 5, the comet appeared about 5°5 mag., having a tail about 1°°5 in length. TEMPEL’s CoMET (1873 II.).— Ephemerts for 12h. Paris Mean Time. 1899. R.A. Decl. Br. Weotels 5 ‘ Peay June 1 19 34 17°4 = '352) SOF meena Sim 37 19°0 3 58 10 Ss 40 18°6 4. Siz ieee 70 Wo AZ 1651... 4 14 21 fo) 5 AG UIT) os. 4. 25 27ers) iat) 49 54... 4 38 45 Heh A Bac iss, 5y7/esaos 4 54 22e hee 25 D5) setOMSAMATeenes 5 D225 As the comet approaches perihelion (June 18) it is rapidly becoming brighter, and should now be visible with small in- struments. It reached its highest northerly declination on May 26, and is now travelling to the south-east through Aquila into the head of Capricornus. New VARIABLE OF ALGoL Typre.—M. Ceraski, of the Moscow Observatory, writes in Astv. Mach. (Bd. 149, No. 3567), announcing the discovery of a new variable of the Algol type in the constellation Cygnus. The star was detected by the varying intensity of its image on photographs taken during May and July 1898. Its position is B.D. + 45°°3062. 1855. R.A. = 2oh, 2m. 24°55. Decl. = + 45° 52°9. Its magnitude is usually about 8°6, but on May 8 this year it was observed to be at minimum about 13°4h., Moscow mean time, its light then being nearly two magnitudes fainter than the normal, VARIABLE RADIAL VELOCITY OF ¢ GEMINORUM.—Prof. W. W. Campbell has called attention to this star in a paper communicated to the Astrophysical Journal (vol. ix. p. 86, 1899), where he gives the results of measures on three photo- graphs. In Ast. Nach. (Bd. 149, No. 3565), M. A. Belopolsky gives the results of an extensive series of measures he has been able to obtain with the 30-inch refractor and two-prism spectro- graph of the Pulkowa Observatory. The individual observations are given, and also a summation in the form of a table showing the radial velocities at stated intervals from minimum, This latter is as follows :— Interval from 2 Interval from . minimum Velocity minimum Wes] | d. h. Weeder. ONe2 + 4°76 g.M Gy ih —270 g.M. Oo 12 + 2°86 6 19 + 1:96 ne +071 | tsa + 3°00 200 + 0°68 |) omy + 3/02 ae +004 9 6 + 5°06 3 12 + 0°50 | 9 15 + 4°41 7 — 0°40 | to 2 + 4°II 4 13 + 0°34 Prof. Campbell’s maximum and minimum values were 20 kil. and 6 kil. respectively. THE RESULTS OF THE “ VALDIVIA” EXPEDITION. : D® SUPAN gives the following summary (based on the official report in the Rezchis-Anzetger of March 25) of the chief results of the German expedition in the Valdivia to Antarctic waters, in the April number of /Pelermann’s Mitteclungen. (1) Rediscovery and determination of position of Bouvet Island, first discovered by Bouvet in 1739, and sighted since then only by Lindsay (t808) and Norris (1825). The island, which lies in lat. 54° 26’ S., long. 3° 24’ E., and is 94 kilo- rt a ett i ae JuNE 1, 1899] INA CE: metres from E. to W. and § kilometres from N. to S., is a volcanic mountain, the edge of the crater rising to a height of 935 metres on the northern side. It is entirely covered with ice, which comes down to sea-level, and presents a steep wall to the sea: it would seem from this that in this region a tongue of polar cold projects northwards, a conclusion supported by the serial temperature observations. No trace of vegetation could be recognised with the telescope, and animal life appeared to be exceedingly scanty. No definite information was obtained as to the existence of Thompson Island. (2) Enderby Land was not visited, as the course was again turned northward at lat. 64° S., but the samples of the sea- bottom yielded evidence that the land is not voleanic. Along the edge of the pack-ice the bottom was covered with diatom ooze, mixed with a larger proportion of clay the nearer Enderby Land was approached. In lat. 63° 17’ S., long. 57° 51’ E., material from ground-moraines, carried to sea by icebergs, was obtained ; this consisted of gneiss, granite, schists, and one large piece of red sandstone. (3) CZimate.—The zone of fresh westerly winds and low barometer extends south of Africa only to lat. 55° S., and of Kerguelen only to 564° S. ; south of this a belt of calms and light variable winds extends to 60° S., and beyond 60° S, the prevailing winds are easterly. In other parts of the Southern Ocean, the westerly winds extend further south, to 60° and 64° S. latitude. Hence it may be supposed that the position of the Antarctic anticyclone is towards the western part of the Indian Ocean, and not directly over the pole. In November 1898 the limit of drift ice was found in long. 7° E., to be in lat. 5623°S. On the voyage from the most southerly point in the neighbourhood of Enderby Land, no ice- bergs were met with north of 61° 22’ S. (4) Oceanography.—Amongst the most important achieve- ments of the Va/divéa expedition is the making of a large num- ber of new soundings, with the discovery of an extensive deep- water area. It has hitherto been assumed that the sea-bottom rose rapidly towards the south from the Eastern Atlantic and the western part of the Indian Ocean, but it now seems likely that deep water extends from both these basins into Antarctic lati- tudes. Kerguelen, and the Crozet and Prince Edward Islands were regarded as projections on the margin of a supposed Antarctic plateau, and this idea had obtained so strong a hold that both V. v. Haardt (1895) and Fricker (1898) simply ignored the soundings of the Chad/enger in their maps, although these had shown depths of over 3000 metres in the Indian Ocean between long. 80° and 95° E. and lat. 60° and 66° S. In the regions sounded by the Valdivia, between 7° and 53. E. long., the depth has been found to exceed 5000 metres. South of the fifty-sixth parallel, the bottom temperature was everywhere below o° C., but nowhere below -—0°'5 C. The serial temperatures in 63°S. lat., 54° E. long., in the month of December, gave the following distribution : (z) a surface layer, 120 metres thick, with temperatures between o° C. and —1°-7 C.; (4) an intermediate layer, about 2200 metres thick, with temperatures above 0° C., and rising to 1°°7 C. ; (c) a bottom layer of equal or greater thickness with temperatures below o C., but never colder than -o°*5. Temperature fell from the surface down to 80 metres, then rose to 1200 metres, and then again fell slowly to the bottom. The same arrangement was found further to the west, but the temperatures were some- what lower, and again to the east, in the track of the Challenger ; but in the latter case the cold surface layer is thicker, and the warm layer usually reaches to the bottom (3000 to 3300 metres), the cold under-layer being only met with in a sounding of over 3600 metres. The lowest temperature observed by the Challenger was -1°*7, the highest only 1°°4. The sea in the region of Enderby Land would thus seem to be favoured by relatively high temperatures, and it remains to bring this into direct relation to the warm Kerguelen stream : this must be done by more observations to the south of Kerguelen. (5) Marine Biogeography.—The quantity of plankton in- creases down to about 2000 metres, diminishing rapidly at greater depths, although no level is destitute of animal life. The quantity of vegetable plankton, on the other hand, reaches its lowest within 300 or 400 metres of the surface. The characteristic of the Antarctic plankton is the abundance of diatoms, and the occurrence of special forms: the appearance of the Antarctic type begins as far north as 40° S., but in 50° S. the presence of forms belonging to warmer seas is still noticeable. NO. 1544, VOL. 60] 115 THE WEARING AWAY OF SAND BEACHES. HE rate of erosion of cliffs and land bordering on the sea, caused by the action of the waves, has been the subject of frequent investigation, and numerous records exist as to the rate at which the land is being encroached on by the sea. On low flat coasts the means of ascertaining the result of the contest between the sea and the land is more difficult to ascertain. The ordinary means of measurement is by a com- parison of old charts, which are seldom trustworthy for this purpose. These charts being for navigable purposes, the depth of the water and the position of objects on shore forming sea marks were the subjects for which accuracy alone was required. The same remarks apply to old plans of estates and manors which were intended to delineate the property of the owners, the sea shore below high water not being a matter requiring trustworthy accuracy. The results obtained by the Department of the Waterstaat in Holland, from periodical measurements of the coast adjacent to the North Sea, are therefore of great interest as showing the effect of the sea on flat beaches in low countries. Between the years 1843-46, the Department caused to be placed all along the Dutch coast, extending from the Helder to the Hook of Holland, a distance of 75 miles, at the foot of the sand hills, oak posts at intervals of one kilometre (‘62 mile) to form a permanent base line; and from these, at regular intervals, measurements have been periodically taken to the foot of the dunes on the land side, and to the low water line on the sea side. The results are recorded in the Proceedings of the Dutch Institution of Civil Engineers.? They are also set out in considerable detail, and tables given for the different periods, in the report of a Commission appointed to investigate the shell fishery of the coast, issued in 1896.* The coast between the two parts named forms the arc of a very large circle, the depth of the embayment in the centre heing 54 miles. The main direction for the southern part faces about N.W., and of the northern part W.N.W. The winds which have most effect on the coast are those from the S. W., changing round to N.W. The set of the flood tide is from south to north, the range decreasing from 5 feet at the Hook of Holland to 4} feet at the Texel. The coast line is bordered seaward by a sand beach extending from 300 to 350 feet to low water, lying at a slope of about 1 in 70; and on the land side by sand dunes, which vary from 1 to 3 miles in width and from 40 to 50 feet in height. These decrease in size towards the Texel. With the exception of the detrital matter brought down in suspension by the river Maas, there is no source for a supply of material to feed the beach. The cliffs which border the French coast, from which the shingle and sand on the beach there is derived, terminate at Sangatte. The drift of the shingle and sand derived from the erosion of these cliffs extends only fora limited distance, and dies outa little beyond Calais and Dunkirk. As regards the Belgian coast, the beach along which consists entirely of sand, from comparisons made by the Government engineers a few years ago of the various charts and plans dating from the beginning of the present century, and from a com- parison of surveys of the coast made in 1833 and 1870, the conclusion was arrived at that no material alteration in the beach of the Belgian coast has taken place, so far as any means of comparison existed; and this was confirmed by measure- ments, taken in 1833 and 1870, of the height of the beach at the groynes at Ostend, Heyst and Wendyke, which showed that there had been no material alteration in the form of the beach. The Dutch coast, between the periods to which the present investigations extend, has been subjected to two disturbing elements, in addition to one abnormally heavy gale in December 1894. The opening out of the new water way to Rotterdam through the Hook of Holland, and the construction of the harbour at Ymuiden for the entrance to the Amsterdam Canal, with the long piers extending across the beach, led to a con- siderable transposition of material at those parts of the shore ; but the effect was local, and extended only over a short distance. As a general result, the measurements show that during the last half-century, on the Dutch coast, the sea has been 1‘ Tidschrift Van het Koningklijk, Instituut Van Ingenieurs ” (1883). 2 Uitkomst Van het Onderzoek of de Schelpvisscherij Langs de Noord- zeekust Nadeelig Kan Zijn Voor Het Weerstandsvermogen Van Het Strand en het Behoud Der Duinen als Zeewering '’ (1896). 116 NA LURE [JuNE 1, 1899 encroaching on the coast. The low water line has crept land- ward, and the beach has become more steep. There has also been a wasting away of the foot of the sand dunes. For the first part of the period over which the observations extend (1843-56), there appears to have been a retreat of the low water line from the shore, and consequent increase in width of the beach, in the northern portion of the coast for the first forty-four miles, and this continued up to 1866 to a less extent. After this, the low water line began to advance land- wards until 1877, when the northern beach began again to grow wider, but the decrease continued along the southern half. On an average there has been a loss of beach along the whole coast between 1846 and 1894, the total average loss for the forty-six years being 155 feet for North Holland and 108 feet for South Holland. The greatest change has taken place between the Helder and Petten, a distance of 12 miles, the low water line having advanced landward an average of 160 feet. Near Callangstoog, where the effect of the great gale of 1894 was most felt, the low water line is from 200 to 270 feet more inland than in 1846, and the foot of the dunes has been driven back more than 300 feet. Near Zandvoort there has been a gain of 100 to 130 feet. Near Scheveningen the low water line has approached nearer the shore, for a length of about four miles for about 200 feet, and the foot of the dunes has been scoured away to an average of 100 feet, and in one place as much as 400 feet. The dunes have also wasted, although in a less degree. From the Helder to Egmont, a distance of 25 miles, there has been an average loss of about 150 feet. From there to Ymuiden the foot of the dunes has remained about stationary ; and from Ymuiden to the Hook of Holland, excluding the part at Scheveningen, there has been an average gain of about 65 feet. Ymuiden Harbour is situated nearly in the centre of the embay- ment, and the piers project about a mile out from the shore. The works were commenced in 1865, and finished in 1876. Since the commencement of the piers, sand has accumulated both on the north and south sides of the harbour, and in 1894 the accumu- lation had extended along the north pier seaward for a distance of about 1500 feet, and along the beach for 14 miles, this being the measure of the two sides of the triangle forming the pocket where the material had collected. On the south side of the harbour the seaward measurement of the accumulation was at the same period 360 feet, and along the beach about 14 miles. The material thus accumulated appears to be due to a trans- position of material, as previous to the piers the beach was increasing at this part of the coast, and has since considerably diminished. The accumulation at the piers, forming the entrance to the Maas, which extend seaward about a mile, has not been so creat. On the north side the sand has extended seaward, since the construction of the piers in 1863-72,820 feet, the width of the extension along the beach being 2 miles. On the south side the accumulation extends outwards 700 feet. Here also there is a corresponding diminution of the beach for some distance to the north of the piers. In December 1894 there occurred a very heavy gale, accom- panied by the highest tide on the Dutch coast recorded during the present century, and an immense amount of damage was done to the fishing fleet. Out of 200 boats moored at the foot of the sand hills near Scheveningen, not one escaped without injury, and many were entirely destroyed. The damage done to the sand dunes, on which this part of the country depends for its protection from the sea, was very extensive, and throughout nearly the whole length the foot was washed away, leaving the mounds with steep sides. The stone pitching on the Helder Sea Dyke was damaged over a surface of about 5000 square yards. In North Holland, the tide broke through the sand hills in several places, and near Callanstoog the hills were breached for a distance of 2 miles, the tide inundating the low land behind. W. H. WHEELER. RESULTS OF THE SCIENTIFIC EXPEDITION TO SOKOTRA. URING the past winter a biological and geographical in- vestigation of the Island of Sokotra (lying in about 12° north latitude and 54° east longitude), some 600 miles south-east of Aden, was undertaken, on behalf of the British Museum, by Mr. W. R. Ogilvie-Grant, and, on behalf of the Liverpool Cor- NO. 1544, VOL. 60] poration, by the Director of Museums (Dr. H. O. Forbes). Mr, W. Cutmore, of the Liverpool Museum, accompanied the party as taxidermist. From the Az/l/etin of the Liverpool Museums we learn that the expedition landed at Aden on November 18, 1898. Political difficulties between the Govern- ment of India and the Sultan of Sokotra unfortunately caused some delay in starting, but through the kindness of the Political Resident, Brigadier-General Creagh, V.C., these days were employed in visiting Sheik Othman and Lahej in South Arabia, where collections of considerable interest were made. On December 1, the difficulties referred to having been surmounted, the party was enabled to leave for Sokotra on board the Royal Indian Marine steamer £/phznstone, which had most generously been placed at its disposal by the Indian Government. Per- mission was also kindly given to detain the vessel for some days at Abd-el-Kuri, a previously unexplored island lying between Sokotra and Cape Guardafui, the eastern horn of Africa. There four days were spent in making as complete a collection of the fauna, flora and geology of the island as the time permitted. On December 7, the expedition was landed on Sokotra, near Hadibu, the capital, and it remained on the island till February 22, 1899. On the return voyage, a second visit was paid to Abd-el-Kuri for a couple of days, to enable more complete col- lections from that out-of-the-way spot to be made. A complete account of Sokotra, with a map, a list of the col- lections, and full descriptions of the new species obtained by the expedition, illustrated by plates and blocks, will be published as a special volume, which is now in active preparation. Mean- while, short diagnoses of some of the more conspicuous zoo- logical novelties are given in the May number of the Bulletin of the Liverpool Museums. Dr. Forbes reports to the Museums Sub-Committee that the share which Liverpool receives of the collections is as follows :—Of mammals, there are examples of one or two species of rat, of one species of civet cat, of one species of bat, and of the wild ass. Of birds, there are some 300 specimens, 250 in skin and 50 in spirit, out of which seven species have been diagnosed as new to science; a large series of reptiles has been acquired, which contains one genus and eight species new to herpetology. Numerous scorpions, millipedes and spiders, their exact number not yet ascertained, have been ob- tained, among which there turn out to be at least one new genus and seven new species ; the land-shells number several thousands, of which Mr. Edgar Smith, ot the British Museum, has already described eight species as new to his department of zoology. No doubt others will prove to be previously un- known. Of insects—almost the whole of which were collected by Mr. Ogilvie-Grant—there are several thousands, the majority of which have not yet been examined. : The plants, of which living specimens or ripe seeds—over 200 in number—have been brought home, are not only of the highest scientific interest, but, being at this moment unique out of Sokotra, are of great commercial value. Their cultivation is being undertaken by Prof. Bayley Balfour in the Royal Botanical Gardens, in Edinburgh. The plants, when in a con- dition to exhibit, will attract the keenest interest of all horti- culturists by the beauty of many of them and by the bizarre form of others. The report states that the true Sokoterians are only poorly civilised Mohamedans, living in caves or rude cyclopean huts, and possess but few utensils, implements, or ornaments, and no weapons. The ethnographical collection is consequently very small. Specimens of their pottery, of their primitive quern-like mills, of their basket work, and of their weaving apparatus were, however, obtained, and also two large blocks of stone, inscribed with an ancient script, which may perhaps throw some light on the indigenes of the island ina past age, and of whose cyclopean remains photographs were obtained. Dr. Forbes concludes his report by pointing out that among scientific circles, especially among geographers and biologists, there has everywhere been expressed the warmest appreciation of the liberality and public-spirited action of the Liverpool Museums Committee and the City Council in taking part in the exploration of Sokotra ; and also a hearty recognition of the great credit which unquestionably belongs to them of having been the first non-metropolitan Committee to recognise that it was the part of a great Corporation possessing an important scientific institution like the Liverpool Museums, not only to furnish their galleries with examples of what is already known, but also to further the advancement and increase of knowledge by actively sharing in the investigation of unknown regions. JuNE 1, 1899] NATURE 117 INIVERSITY AND EDUCATIONAL INTELLIGENCE. OxrForpD.—The 202nd meeting of the Junior Scientific Club was held on May 26. After private business, Mr. J. M. Wadmore (Trinity) read a paper on caoutchouc; Mr. M. Burr (New College) exhibited some live walking-stick insects ; and Mr. H. E. Stapleton (St. John’s) read a paper on Dulong and Petit’s law. AN exhibition of practical work executed by candidates at the recent technological and manual training examinations of the City and Guilds of London Institute will be opened by the Duke of Devonshire, at the Imperial Institute, on Friday, June 9. Tue Edinburgh correspondent of the Zazce¢ states that the court of the University of Edinburgh had recently before them a report from the committee appointed to draw up a statement and appeal for funds for University purposes, in which it was stated that the funds required for the equipment of the Public Health Laboratory and for the preparation of a library catalogue had been provided, the former by the generosity of Mr. John Usher of Norton, and the latter from the munificent bequests of the late Sir William Fraser. For the library, however, funds are still urgently required. The most pressing wants are: (1) a fire-proof room for the storage of rare books of the fifteenth and early sixteenth centuries and the MSS., which number about 7000; (2) a fund, amounting at the lowest figure to 25,000/., for the purchase of scientific and literary journals and of larger works of reference ; and (3) extensive structural changes and new book-cases, costing at least 5000/., or a new and suit- able building for the library. Another direction in which it will soon be necessary to spend money is the establishment of the Physical Laboratory. The construction and equipment of this laboratory will be a large undertaking, but it is one which will have soon to be faced if the scientific reputation of the University is to be maintained. SCIENTIFIC SERIALS. American Journal of Science, May.—Some experiments with endothermic gases, by W. G. Mixter. The endothermic gases operated upon were acetylene, cyanogen, and nitrous and nitric oxides. A beautiful experiment described is one in which acetylene is decomposed at a dull red heat. The gas issues from a narrow tube into a wider tube, heated by a Bunsen burner. When the glass begins to glow there is a slight puff, and the stream of gas issuing from the narrow tube .glows, or rather the carbon particles glow in it with the heat of dissocia- tion of the acetylene.—A hypothesis to explain the partial non- explosive combination of explosive gases and gaseous mixtures, by W. G. Mixter. Detonating gas, a mixture of carbonic oxide and oxygen, one of cyanogen and oxygen, and other explosive mixtures of gases, do not explode below certain pressures when sparked. Explosions do not occur because of the infrequency of impacts of molecules having a velocity or internal energy adequate for chemical union. Some of the molecules combine, but the heat of their union is not sufficient to restore the energy lost by radiation, and the change is therefore not self-propagat- ing.—Occurrence of palzotrochis in volcanic rocks in Mexico, by H. S. Williams. Origin of palzotrochis, by J. S. Diller. These two papers effectually dispose of the hypothesis of the organic origin of the siliceous formations described by Emmons as due to some primordial coral. Prof. Williams describes some specimens coming from an old eroded volcanic cone made up of altered porphyry and volcanic tuffs, situated north-east of Guanajuato in the Santa Rosa mountains. A microscopical study of thin sections reveals the fact that the nodules are spherulites, acommon feature of acid igneous rocks. —Association of argillaceous rocks with quartz veins in the region of Diamantina, Brazil, by O. A. Derby. Red clay is always associated with the quartz veins of the diamond region of Minas Geraes, Brazil. The author describes a remarkable layer of that kind, one to two metres thick, which has received from the miners the name of Guza (Guide), because, as they state, diamonds were to be looked for below the outcrop of this layer, and not above it.—Volatilisation of the iron chlorides in analysis, and the separation of the oxides of iron and aluminium, by F. A. Gooch and F. S. Havens. NO. 1544, VOL. 60] The fact that ferric oxide is completely volatile in HCl gas applied at once at a temperature of 500°, and at 200° if the acid carries a little chlorine, opens the way to many analytical separations of iron, notably to the separation of intermixed iron and aluminium oxides.—Preliminary note as to the cause of root pressure, by R. G. Leavitt. The author applies the latest researches on osmotic pressure to the known facts of plant physiology. Bulletin of the American Mathematical Society, May.—Prof. Holgate gives an account of the April meeting, of the Chicago Section, at Evanston, April 1. There were two sessions in the day, and twelve papers were communicated.—Prof. Bécher gives an elementary proof that Bessel’s functions of the Zeroth order have an infinite number of real roots. This was read at the Society’s February meeting (cf Gray and Mathews’ “ Treatise on Bessel Functions,” p. 44.) A generalisation of Appell’s factorial functions (read at the December 1898 meeting), by Dr. Wilczynski, is a slight modification of Appell’s proof. The writer proposes to discuss these functions more fully later on. A paper, read at the February meeting, by Prof. J. Pierpont, entitled “‘ On the Arithmetization of Mathematics,” is an attempt to show why arithmetical methods form the only sure founda- tion in analysis at present known. General reasons are indicated in a paper by Klein (‘‘ iiber Arithmetisirung der Mathematik,” Gottinger Nachrichten, 1895). The paper enters into consider- able detail. There is much metaphysics as well as mathematics. —Prof. E.W. Brown contributes an appreciatory review of Prof. Darwin’s work onthe tidesard kindred phenomena of the solar system, and also notices ‘* Lecons sur la théorie des Marées,” by Maurice Lévy.—The Notes give an account of a projected change in the ‘‘ Annals of Mathematics,” which is to be in- augurated in vol. xiii., and a full list of the subjects of lectures at a dozen German universities, besides some notes of personal matters. Wiedemann’s Annalen der Physik und Chemie, No. 4.— Pitches of very high notes, by F. Melde. The author reviews the various methods by which very high pitches have been determined. These include subjective methods like those by direct hearing and by difference tones, and objective ones like the various vibrographs and the author’s own method of reson- ance. The author admits that the method of difference tones is untrustworthy, and points out certain advantages of the sensitive flame which might be utilised.—Viscosity of gases, by P. Breitenbach. Of the two methods for determining the viscosity of gases, that of transpiration through a capillary tube, and that of the oscillation of a solid, the latter indicates a greater increase ° of viscosity in the temperature. But in any case the increase is not quite proportional to the temperature.—Effect of electric oscillations upon moist contacts, by E. Aschkinass. Two pointed copper wires which just touch each other act as an ordinary coherer in air or alcohol, but when immersed in water, or when the points are only connected by a drop of water, the action is reversed, since electric waves have the effect of tem- porarily increasing instead of reducing the resistance. In another form of the experiment, a few drops of water are added to the copper filings of an ordinary coherer. This reversed action is as yet entirely unexplained.—Emission and absorption of platinum black and lamp black with increasing thickness, by F. Kurlbaum. The emission of blackened surfaces is compared with that of an ‘‘absolutely black body” in the shape of an orifice of a brass vessel blackened inside and kept at a constant temperature by circulating steam. A bolometer is exposed to radiation from this orifice and to films of black substances kept at the same temperature. It appears that platinum black has a higher absorptivity and emissity at greater thicknesses, whereas that of lamp black is greater in very thin layers. Neither of these substances absorbs heat rays of great wave-lengths. For most purposes, platinum black is to be preferred, if only on account of the facility in controlling its electrolytic deposition. —Radius of molecular action, by W. Mueller-Erzbach. Films of bees-wax or sealing-wax were protected by thin layers of gum against the dissolving action of carbon bisulphide vapour. The thickness of the layer of gum required for effectively protecting sealing-wax was 0°35 mm., whereas bees-wax was sufficiently protected by a layer only 0°14 mm. thick. THE April issue (vol. Ixv. part 4) of the Zeztschreft fiir Wissenschaftliche Zoologie contains five articles, of which, per- haps, the one by Messrs. Eimer and Fickert, on the evolutionary history of the Foraminifera, is the most generally interesting, 118 NATO [JUNE 1, 1899 More than one hundred pages of the journal are devoted to this subject ; and the elaborate genealogical tree given on p. 464 supplies in concise form the general results of the authors’ investi- gations. The other articles include one on the Infusoria found in the stomachs of domestic Ruminants, by A. Giinther ; one on ihe urinogenital system of certain Chelonians, by F. von Miiller ; a third, by J. Meisenheimer, on the morphology of the kidneys of the Pulmonate Mollusca; and a fourth, by G. Forssell, on the Lorenzinian ampullz in the Spiny Dogfish. After describing in detail the histology of these head-organs, the author considers that further experiments must be made before their precise function can be fully determined. SOCIETIES AND ACADEMIES. LONDON. Physical Society, May 26.—Mr. T. H. Blakesley, Vice- President, in the chair.—A paper, by Prof. S. Young and Mr. Kose-Innes, on the thermal properties of normal pentane (Part 2), was read by Mr. Rose-Innes. In the first paper on this subject, read before the Physical Society last December, it was shown that the relations existing between the volume temperature and pressure of normal pentane could be closely represented by the equation RT f e \ Z Seedy ah eas — re v \ vth— gs wu + &) This formula was first used in connection with isopentane, and it has been shown that the values of R and Z/e are the same for the two isomers. The authors find that if 7 and e be taken separately equal to each other, and if the constants 4 and ¢ be calculated from experiments on normal pentane, errors of 2 per cent. occur between the calculated and experimental results. This point has been investigated both algebraically and graph- ically, and the supposition that these constants are separately equal has been thought incorrect. Taking the values of R, i/e, and gas being the same in the two pentanes, the constants ¢and & have been determined, and by this means the relations letween volume temperature and pressure have been represented ly the formula to within 1 percent. The authors conclude that the difference in pressure of two isomeric substances at a given volume and temperature is of the same order as the devi- ation from Boyle’s law, and involves the second power of the density. Mr. Rose-Innes said the formula proposed was not an absolute solution of the problem, although it was the best of a large number which had been tried. It has been applied with success to Andrews’ experiments on carbonic acid, and to experiments which have been made upon ether and hexane. In the latter case, the range in volume was too small to afford a rigorous test of the value of the formula. The range in volume in isopentane was from 4000 to 3°4 ; in normal pentane, from 300 to 3°43 and in ether, from 350 to 3°4. The tem- perature varied in different experiments from 40° C. to 280° C. Objections have been raised to the formula on account of the number of constants it contains and its complexity. Mr. Rose- Innes pointed out that it was necessary to have a complex formula, as they were not dealing with a simple problem, but with the results of experiments which went so far below the critical temperature that the volume occupied was only 34 times as great as the space which would have been occupied by the molecules at their closest packing. The reader of the paper compared the proposed formula with formule of Clausius, Sutherland, and Tait containing four, four, and six constants re- ~pectively, and finally with the original equation of Van der Waals applied to experimental results by Amagat. It was shown that the agreement was much closer and the range greater. Prof. Callendar expressed his interest in the wide ap- plicability of the authors’ formula, and asked if any theoretical significance could be assigned to the various constants which appeared. Mr. Rose-Innes said the R of their formula was the K of the perfect gas equation, and that the / and e corresponded respectively to the 8 and a of the ordinary Van der Waals ex- pression. So far as he knew, the £ and ¢ were meaningless. — A paper on the distribution of magnetic induction in a long iron bar, by Mr. C, G. Lamb, was postponed until the next meeting. Chemical Society, May 18.—Prof. Thorpe, President, in the chair.—The following papers were read :— Corydaline (Part vi.), by J. J. Dobbie and A. Lauder. Corydaldine, C, H;,NO(OMe)s, NO. 1544, VOL. 60] an oxidation product of corydaline, is shown to be closely re- lated to oxyhydrastinine ; the so-called corydalinic acid is an acid ammonium hemipinate.—Oxidation of furfural by hydrogen peroxide, by C. F. Cross, E. J. Bevan and T. Heiberg. Fur- fural is oxidised by hydrogen peroxide in presence of iron salts to a hydroxyfurfural and the corresponding hydroxypyromucic acid ; the hydroxyfurfural reacts with phloroglucinol and resor- cinol in a similar way to the lignocelluloses. It is shown thus that a furfuralphenol is a constituent of the lignocelluloses.— Note on the reactions between sulphuric acid and the elements, by RK. H. Adie.—On the action of ethylene dibromide and of trimethylene dibromide on the sodium derivative of ethylic cyanacetate, by H. C. H. Carpenter and W. H. Perkin, jun. Improved methods for preparing tri- and tetra-methylene deri- vatives are given. Ethylic trimethylenecyanocarboxylate (1,1), is prepared by the action of ethylene bromide on ethylic sodio- cyanoacetate, and ethylic tetramethylenecyanocarboxylate (1,1), is obtained by the action of trimethylene bromide on ethylic sodiocyanoacetate ; the salts are hydrolysed by cold alcoholic potash with formation of the corresponding acids.—The maxi- mum vapour pressure of camphor, by R. W. Allen. Experi- mental values for the maximum pressures of camphor vapour at o-8o° are given. Linnean Society, May 4.—Mr. A. D. Michael, Vice- President, in the chair —Mr, I. H. Burkill exhibited speci- mens of a daisy (Belles perennis), found at Kew, in which the ray of the outer florets was so nearly absent that these consisted of scarcely more than ovary, naked style, and stigma.—Mr. F. G. Parsons read a paper on the position of Anomalurus as indicated by its myology. The paper contained an account of the muscles of Anomalurus, and a comparison of them with those of the different suborders of rodents, From previous examination of the muscles of rodents, the author arrived at the conclusion that Azomalurus should be placed among the Sciuromorpha, but that it had certain Myomor- phine tendencies. He contrasted its muscles with those of Pedetes caffer, but found little reason to regard these two animals as nearly related. —Mr. George Murray, F.R.S., on behalf of Miss Ethel S. Barton, communicated a paper on Votheza anoma/a, an obscure species of parasitic Alga, and described its mode of growth and reproduction, some remarks being made by Mr. W. Carruthers, F.R.S.—A paper by Mr. George West on variation in Desmids was read. The Desmidieze was shown to be morpho- logically specialised and to exhibit a marked pattern and symmetry of form, major and minor symmetries being recognis- able in many species. Variations in form and symmetry were specially dealt with, and a summary given of all that is known concerning the variation in the cell-contents and in the conju- gation of these plants. Observations were also made on the variability of the pyrenoids and moving corpuscles in the genus Clostertum. Geological Society, May 1o.—W. Whitaker, F.R.S., President, in the chair.—The geology of the Davos district, by A. Vaughan Jennings. Alpine geology has attracted many workers since the date of Prof. Theobald’s classic memoir on the district of which Davos forms part, and new principles of interpretation have been established. The author has more especially studied (a) the age of certain rocks formerly classed as ‘‘ Biindner Schiefer,” but distinct from the grey shales variously regarded as of Jurassic or Tertiary age ; (4) the origin and date of the serpentine near the Davoser See ; and (c) the tectonic structure of the district. The author discusses at length the physical structure of the district. The general trend of the Davos Valley is rather oblique to that of the greater rock- masses, which, however, is somewhat irregular. He shows that these (which have a general dip towards the south and east) form three great acute and rudely parallel over-folds, the westernmost being theemost complicated ; of this fold, the ser- pentine forms a part. It is more recent than the crystalline schists and the Casanna Schiefer, and is associated with the red and green schistose rocks already mentioned, in a way which he considers indicative of intrusion; but it nowhere cuts the Haupt-Dolomit. Accordingly he considers it to be later than the Verrucano, and not earlier than the middle part of the Trias. Certain crystalline breccias occur in the neighbourhood of the serpentines ; these the author considers to be due to earth-movement, and he goes on to give reasons for regarding them as the equivalent of the Casanna Schiefer of other locali- ties. There is, in his opinion, no evidence of the presence of EE JuNE 1, 1899] NATURE 119 post-Jurassic strata such as Prof. Steinmann believes to exist.— Contributions to the geological study of County Waterford. Part 1, §i. The Lower Palzeozoic bedded rocks of the coast, by F. R. Cowper Reed. This paper opens with an account of the previous publications on the geology of the district, and then goes on to describe the sections exposed along the coast at the following localities: Raheen and Newtown Head, Tramore Bay, Garrarus and Kilfarrasy, Annestown and Dunabrattin, Knockmahon, Ballydouane Bay, and Killelton Cove to Bally- voyle. These sections expose shales and limestones with abundance of igneous rocks partly interbedded, but mainly in- trusive ; and the author is able to make out the following suc- cession of rocks, tabulated in descending order: (4) Raheen Series. Mudstones, slates, felsites and tuffs, and fossiliferous shales. (3) Carrigaghalia Series. Graptolitic shales, thin flags, cherts, tuffs, and felsites. (2) Tramore Limestone Series. Divided into three stages. (1) Tramore Slates. Calcareous and argillaceous slates. Zoological Society, May 16.—Dr. W. T. Blanford, F.R.S., Vice-President, in the chair.—The Secretary read extracts from letters received from Mr. J. S. Budgett, contain- ing an account of the progress of his expedition to the Gambia, and announcing his proposed return in July next.—Mr. G. A. Boulenger, F.R.S., exhibited a specimen of the Bornean lizard (Lanthanotus borneensts), belonging to the Sarawak Museum, and remarked that it was the second example of this reptile that had reached Europe. An examination of the specimen had con- firmed Mr. Boulenger’s suspicion that its affinities were with the Helodermatidae, and that it was not, as its original describer (Steindachner) had supposed, entitled to family rank by itself. —Mr. G. E. H. Barrett-Hamilton exhibited the skins of two hares (Zepus vartabzlis), and made some remarks on the winter whitening of Mammals in connection therewith.—Mr. G. A. Boulenger, F.R.S., read an account of the fishes obtained by the Congo Free State Expedition, under Lieutenant Lemaire, in Lake Tanganyika, in 1898. Ten new species were described, of which three were made the types of new genera.—Mr. E. M. Corner read a note on the variations of the patella in the divers, grebes, and cormorants, by which the functions of the bones in these birds were explained.—A communication was read from Mr. Stanley S. Flower, containing notes on a second collection of reptiles made in the Malay Peninsula and Siam, from Novem- ber 1896 to September 1898, and a list of the species recorded from those countries. The species enumerated in the paper -were 221, of which one was the type of a new species, de- scribed under the name of Zyphlops flowerd by Mr. G. A. Boulenger.—A communication was read from Marquis Ivrea on the wild goats of the A®gean Islands. JuNE 8, 1899] University of Bombay—Dr. H. M. Birdwood, M.A., C.S.1. University of Calcutta—Hon. J. O’Kinealy, M.A , Judge of H.M.’s High Court of Bengal. University of Madras—IHon. H. H. Shephard, M.A., Puisne _ Judge of the High Court of Madras. ~ London Mathematical Society—Lord Kelvin, M.A., Hon. LL.D., President. University of Tokio, Keishiro Matsui, Chargé d’Affaires, Japanese Legation, London. University of New Zealand—Edward John Routh, M.A., Sc. D. Durham College of Science, Newcastle-on-Tyne—Henry Palin Gurney, M.A., Principal. University of Adelaide—Horace Lamb, M.A., Professor of Mathematics in Owens College, Manchester. University College of Wales, Aberystwyth—Robert Davies Roberts, M.A. Yorkshire College, Leeds—Leonard J. Rogers, M.A., Pro- fessor of Mathematics. Physical Society of London—Oliver J. Lodge, D.Sc., Pro- fessor of Physics, University College, Liverpool, President. Mason College, Birmingham—John Henry Poynting, Sc.D., Professor of Physics. Baltimore (Johns Hopkins)—Simon Newcomb, Hon. Sc.D., LL.D., Professor of Mathematics and Astronomy; and Pro- fessor Ames. Firth College, Sheffield—William Mitchinson Hicks, Se.D., Principal. University College, Bristol—Frank R. Barrell, M.A., Pro- fessor of Mathematics. City and Guilds of London Institute for Advancement of Technical Education—Sir Frederick Abel, Bart. University College, Dundee—John Yule Mackay, Principal. University College, Nottingham—John Elliotson Symes, M.A., Principal. Victoria University—Nathan Bodington, Litt.D., Vice-Chan- cellor. Royal University of Ireland—Right Rev. Monsignor Molloy, OED DES Royal College of Science for Ireland—Walter Noél Hartley, Professor of Chemistry. University College, Liverpool—Richard Tetley Glazebrook, M.A., Principal. University of the Punjab—Sir Charles Arthur Roe, M.A., fate First Judge of the Chief Court, Punjab ; late Vice-Chan- cellor of the University. University College of South Wales, Cardiff—H. W. Lloyd Tanner, M.A. (Oxon.), Professor of Mathematics. University College of North Wales, Bangor—Henry R. Reichel, M.A. (Oxon.), Principal. Royal Indian Engineering College, Coopers Hill—Prof. A. Lodge, M.A. (Oxon.), Professor of Mathematics University of Allahabad—G. Thibaut, Ph.D., Principal of the Muir Central College, Allahabad. University of Wales—J. Viriamu Jones, M.A., Vice-Chan- cellor. In addition to the delegates officially appointed, the University entertained a number of distinguished guests, amongst whom the names of the following may be mentioned -— Captain Abney, C.B., S. Kensington; Prof. W. G. Adams, King’s College, London; Prof. H. E. Armstrong, City and Guilds Institute, S. Kensington; Prof. Arrhenius, Stockholm ; Prof. Ayrton, City and Guilds Institute, S. Kensington; Prof. Barker, University of Pennsylvania, Philadelphia, U.S.A. ; Mr. Shelford Bidwell ; Dr. Bottomley, The University, Glasgow ; Mr. C. V. Boys, London ; Sir Frederick Bramwell, Bart. ; Dr. Haig Brown; Prof. W. Burnside, Greenwich ; Prof. Clifton, Oxford ; Prof. Egoroff, St. Petersburg ; Prof. Esson, Oxford ; Sir John Evans, K.C.B.; Prof. Carey Foster, London; Dr. F. Galton ; Sir A. Geikie; Prof. Andrew Gray, Bangor; Prof. Hele-Shaw; Mr, Hubert Herkomer, R.A. ; Sir J. D. Hooker, C.B., G.C.S.I.; Prof. J. Joly, Dublin; Prof. Kayser, Bonn ; the Hon. Sir W. R. Kennedy ; Sir J. Norman Lockyer, K.C.B.; Major P. A. MacMahon; Prof. van der Mensbrugge, Ghent ; Prof. Michelson, Chicago ; Prof. G. M. Minchin, Coopers Hill; Prof. G, Mittag-Leffler, Stockholm; Mr. Ludwig Mond; Mr. J. Fletcher Moulton, M.P., Q.C.; Prof. Nernst, Gottingen ; Prof. Karl Pearson, University College, i NO. 1545, VOL. 60] NATURE 27, London; Prof. Perry, Royal College of Science; Sir John Phear; Prof. Quincke, Heidelberg; Lord Rayleigh, Lord Lieutenant of Essex; Prof. H. F. Reid, Baltimore; Prof. Osborne Reynolds, Manchester; Sir W. C. Roberts-Austen, K.C.B., Royal College of Science, London; Sir Henry E. Roscoe, Vice-Chancellor of the University of London; The Rev. Dr. Salmon, Provost of Trinity College, Dublin ; Prof. Schuster, Manchester ; Sir R. Strachey, G.C.S.I.; Mr. J. W. Swan ; Mr. H. Thornycroft, R.A. ; Prof. H. H. Turner, Oxford ; Prof. Voigt, Gottingen ; Rt. Rev. Lord Bishop of Wakefield ; Rear- Admiral Sir William Wharton, K.C.B.; Sir W. H. White, K.C.B. At 1.30 the Vice-Chancellor gave a lunch at Downing College to some 400 of the delegates and their hosts, and at 2.45 a congregation was held in the Senate House at which his Grace the Chancellor presided. The following address from the University was then read by Dr. Sandys, the Public Orator, and presented to Sir George Stokes, accompanied by a gold medal struck to com- memorate the occasion. Quod per annos quinquaginta inter nosmet ipsos Professoris munus tam praeclare ornavisti, et tibi, vir venerabilis, et nobis ipsis vehementer gratulamur. Iuvat vitam tam longam, tam serenam, tot studiorum fructibus maturis felicem, tot tantisque honoribus illustrem, tanta morum modestia et benignitate insignem, hodie paulisper contemplari. Anno eodem, quo Regina nostra Victoria insularum nostrarum solio et sceptro potita est, ipse eodem aetatis anno.Newtoni nostri Universitatem iluvenis petisti, Newtoni cathedram postea per decem lustra ornaturus, Newtoni exemplum et in Senatu Britannico et in Societate Regia ante oculos habiturus, Newtoni vestigia in scientiarum terminis proferendeis pressurus et ingenii tanti imaginem etiam nostro in saeculo praesentem redditurus. Olim studiorum mathematicorum e certamine laurea prima reportata, postea {ne plura commemoremus) primum aquae et immotae et turbatae rationes, quae hydrostatica et hydrodynamica nom- inantur, subtilissime examinasti; deinde vel aquae vel aéris fluctibus corporum motus paulatim tardatos minutissime per- pendisti; lucis denique leges obscuras ingenii tui lumine luculenter illustrasti. Idem etiam scientiae mathematicae in puro quodam caelo diu vixisti. atque hominum e controversiis procul remotus, sapientiae quasi in templo quodam sereno per vitam totam securus habitasti. In posterum autem famam diuturnam tibl propterea praesertim auguramur, quod, in inventis tuis pervulgandis perquam cautus et consideratus, nihil praeproperum, nihil immaturum, nihil temporis cursu postea obsolefactum, sed omnia matura et perfecta, omnia omnibus numeris absoluta, protulisti. Talia propter merita non modo in insulis nostris doctrinae sedes septem te doctorem honoris causa nominaverunt, sed etiam exterae gentes honoribus eximiis certatim cumu- laverunt. Hodie eodem doctoris titulo studiorum tuorum socios nonnullos exteris e gentibus ad nos advectos, et ipsorum et tuum in honorem, velut exempli causa, libenter ornamus. In per- petuum denique observantiae nostrae et reverentiae testimonium, in honorem alumni diu a nobis dilecti et ab aliis nomismate honorifico non uno donati, ipsi nomisma novum cudendum curavimus. In honore nostro novo in te primum conferendo, inter vitae ante actae gratulationes, tibi omnia prospera etiam in posterum exoptamus. The medal was designed by Mr. De Saulles, who designed the jubilee medals, and bears the head of the recipient in profile on the obverse, and some lines in Latin written by the Master of Trinity on the reverse. By the courtesy of the University Press, we are able to give the accompanying illustrations of the medal. The likeness is remarkably good, and the medal, replicas of which, in bronze, will be presented to the official delegates, was universally admired. We are informed that copies in bronze of the medal may be obtained from Messrs. Macmillan and Bowes. The number of medals struck is limited. After the medal had been presented to Sir George by the Chancellor, Prof. Cornu advanced and presented on behalf of the Institute of France a copy of the Arago medal in gold. Immediately after the cere- mony, honorary degrees of Doctor of Science were 128 NALTORE [June 8, 1899 conferred upon the following distinguished visitors :— Prof. M. A. Cornu, Member of the Institute of France, Professor of Experimental Physics in the Ecole Poly- technique of Paris ; Prof. J. G. Darboux, Member of the Institute of France and Professor of Higher Geometry in the University of Paris; Prof. A. A. Michelson, Pro- fessor of Experimental Physics in the University of Chicago ; Prof. M. G. Mittag-Leffler, Professor of Pure Mathematics at Stockholm; Prof. G. H. Quincke, Professor of Experimental Physics in the University of Heidelberg ; and Prof. W. Voigt, Professor of Mathe- matical Physics in the University of Gottingen. Prof. F. W. G. Kohlrausch, Director of the Physikalisch- Technische Reichstanstalt, Charlottenburg, was un- fortunately deterred by illness from attending to receive Wie YT ILL STR LLOSOPENA LL SHOES RPE JRE CANE YIN QPAM LPS] VITA Cae rom raat TALL iN OY LA inter lumina numeratur, qui olim fratrum nostrorum trans- marinorum in classe non ignotus, lampade trans oceanum e Gallia sibi tradita feliciter accepta, etiam exteris gentibus subito affulsit, velocitatem immensam eleganter dimensus, qua lucis fluctus videntur (ut Lucretii verbis utar) ** ber totum caeli spatium diffundere sese, perque volare mare ac terras, caelumque rigare.” (4) Pror. MiTTaG-LEFFLER (STOCKHOLM), Scandinavia ad nos misit scientiae mathematicae professorem illustrem, qui studiorum suorum velut e campo puro laudem plurimam victor reportavit. Idem Regis sui auspiciis, qui praemiis propositis magnum huic scientiae attulit adiumentum, etiam exterarum gentium ad communem fructum prope vigint? per annos Acta illa Mathematica edidit, quae in his studiis quasi gentium omnium internuntium esse dixerim. Ipse The Stokes Jubliee Medal. the degree which the University had been anxious to confer upon him. The following are the speeches delivered by the Public Orator in presenting to his Grace the Chancellor the several recipients of the honorary degree. (1) PRor. Cornu (PARIS). Primum vobis praesento artium plurimarum Scholae Paris- iensis professorem, quem in hoc ipso loco die hesterno per- spicuitate solita disserentem audivistis, virum non modo solis de lumine in partes suas solvendo, sed etiam orbis terrarum de mole metienda per annos plurimos praeclare meritum. Lucis in natura explicanda, quanta cum doctrinae elegantia, quanta cum experimentorum subtilitate, quam diu versatus est.’ Idem quam accurate velocitatem illam est dimensus, qua per aeris intervallum immensum lucis simulacra minutissima transvolitant, “* Suppeditatur enim confestim lumine lumen, et quasi protelo stimulatur fulgere fulgur.” Lucis transmittendae in Acuradnpopia quam feliciter lampada a suis sibi traditam ipse etiam trans aequor Atlanticum alii tradidit. (2) Pror. DarBoux (Paris). Sequitur deinceps vir insignis Nemausi natus, Parisiensium in Universitate illustri geometriam diu professus et scientiarum facultati toti praepositus. Peritis mota sunt quattuor illa volumina, in quibus superficierum rationem universam inclusit ; etiam pluribus notum est, quantum patriae legatus deliberation- ibus illis profuerit, quae a Societate nostra Regia primum in- stitutae, id potissimum spectant, ut omnibus e gentibus quic- quid a scientiarum cultoribus conquiritur, indicis unius in thes- aurum, gentium omnium ad fructum, in posterum conferatur. Incepto tanto talium virorum auxilio ad exitum perducto, inter omnes gentes ei qui rerum naturae praesertim scientiam exco- lunt, sine dubio vinculis artioribus inter sese coniungentur. (3) Pror. MicHELSON (CHICAGO), Trans aequor Atlanticum ad nos advectus est vir insignis, qui ea quae professor noster Lucasianus de aetheris immensi regione, in qua lux propagatur, orbis terrarum motu perturbata, olim praesagiebat, ipse experimentis exquisitis adhibitis penitus ex- ploravit. Lucis explorandae in provincia is certe scientiarum NO. 1545, VOL. 60] Homerus (ut Pindari versus verbo uno tantum mutato proferam) ayyerov eodrdy pa Tia meyloray mpayuar mavT) pepew: abteTat kal Md Onots d¢ ayyeAlas opdas. (5) PRoF. QUINCKE (HEIDELBERG). Universitatem Heidelbergensem abhinc annos quadraginta pro- fessorum par nobile spectroscopo invento in perpetuum illus- travit. Adest inde discipulorum plurimorum in scientia physica praeceptor, qui et in instrumentis novis inveniendis sollertiam singularem et in eisdem adhibendis industriam indefessam prae- stitit. Ei qui in scientiae physicae ratione universa versati, viri huiusce inventis utuntur, etiam de sua scientia verum esse confitebuntur, quod de arte oratoria praesertim dixit Quinti- lianus :—‘‘in omnibus fere minus valent praecepta quam ex- perimenta.”’ (6) Pror. VorcT (GOTTINGEN). Universitatem Goettingensem, a Rege nostro Hanoveriensi Georgio secundo conditam, vinculo non uno cum Universitate nostra coniunctam esse constat. Constat eandem etiam per annos prope quinquaginta Caroli Frederici Gaussii, scientiae mathematicae et physicae professoris celeberrimi, gloria esse illustratam, qui curh ingenio fecundissimo disserendi genus con- summatum coniunxit. Iuvat inde professorem ad nos advectum excipere, qui scientiae eiusdem pulcherrimam nactus provinciam, etiam lucem ipsam et crystalla ingenii sui lumine illustravit. After the congregation, a garden party was held in the beautiful old gardens of Pembroke College, where a numerous and brilliant company assembled and listened to the music of the Royal Artillery Band. In the evening, a dinner, at which were present some 220 of the guests of the University and their hosts, took place in Trinity College Hall. His Grace the Duke of Devonshire presided, and after the health of the Queen had been drunk he proposed, in a felicitous speech, the health of the hero of the day. The toast was drunk with the greatest enthusiasm. The only other toasts were “The Guests,” proposed by Prof. George Darwin, and responded to by Lord Lister ; and “ The Chancellor,” pro- posed by the Vice-Chancellor. In responding, the Chancellor thanked the Master and Fellows and Trinity JUNE 8, 1899] NATURE 129 for their hospitality in granting the use of the Hall, and Dr. Butler replied on behalf of the College. In addition to the guests who were more directly asso- ciated with the celebration of the jubilee, the following were present at the banquet :—Mr. Justice Mathew, the High Sheriff of Cambridgeshire, the Lord Lieutenant of Cambridgeshire, the Bishop of Ely, the Right Hon. A. J. Balfour, and many other distinguished guests. This dinner brought the official proceedings to an end, but on Monday a meeting of the Philosophical Society was held for the presentation of papers to be published in a special volume of the Society’s 7yansactions commem- orative of the long connection of Sir G. G. Stokes with the Society. The following are amongst those who formally communicated papers :— I. By Prof. M, G. Mittag-Leffer: On the analytical representation of a uniform branch of a monogenic function. II. By Prof. H. Poincaré : By Dr. L. Boltzmann : By Prof, A. Righi : V. By Prof. A. A. Michelson : scope. The theory of groups. On the echelon spectro- VI. By Major P. A. Macmahon, R.A.: Application of the partition analysis to the study of the properties of any system of consecutive integers. VII. By Lord Kelvin: On diffraction of solitary waves. VIII. By Prof. A. Schuster: On the periodogram of mag- netic declination derived from twenty-five years’ observations at the Greenwich Observatory. IX. By Prof. W. D. Niven: ROE PHOTOGRAPHIC SociETY, at 8.—Acetylene: Prof. Vivian B. ewes. THURSDAY, JuNE 15 Royat Society, at 4.—Prof. A.: Michelson will read a Paper.—The Colour Sensations in Terms of Luminosity: Captain Abney, F.R.S.—A Comparison of Platinum and Gas Thermometers at the International Bureau of Weights and Measures at Sévres: Dr. J. A. Harker and Dr. P. Chappuis.—On a Quartz-Thread Gravity Balance: R. Threlfall, F.R.S.—On the Orientation of Greek Temples, being the Results of some Observations taken in Greece and Sicily, in May, 1898: F. C. Penrose, F.R.S.—A Preliminary Note on the Life-History of the Organism found in the Tsetze Fly Disease: Dr. H. G. Plimmer and Dr. T. Rose Bradford, F.R.S.—And other Papers. Linnean Society, at 8.—Contributions to the Natural History of Lake Urmi and its Neighbourhood: R. T. Giinther.—A Systematic Revision of the Genus Najas: Dr. A. B. Rendle.—On the Anatomy and System- atic Position of some Recent Additions to the British Museum Collection of Slugs: Walter E. Collinge.—The Edwardsia Stage of Lebrunia, and the Formation of the (Esophagus and Gastro-ccelomic Cavity: J. E. Duerden. Cuemicat Society, at 8.—Ballot for the Election of Fellows.—On the Decomposition of Chlorates, with special reference to the Evolution of Chlorine and Oxygen: W. H. Sodeau.—The Action of Hydrogen Peroxide on Formaldehyde: Dr. A. Harden.—Homocamphoronic and Camphononic Acids: A. Lapworth and E, M. Chapman.—Action of Silver Compounds on a-Dibromocamphor : A. Lapworth.—-The Colouring Matter of Cotton Flowers : A. G. Perkin —Experiments on the Synthesis of Camphoric Acid: H. A. Auden, W. H. Perkin, jun., and J. L. Rose.— Methylisoamylsuccinic Acid, Part I.: W. T. Lawrence. y NO. 1545, VOL. 60] BOOKS, PAMPHLETS, and SERIALS RECEIVED. Booxs.—The Hereford Earthquake of December 17, 1896: Dr. C. Davison (Birmingham, Cornish).—Physikalisches Praktikum: E. Wiede- mann u. H. Ebert, Vierte Auflage (Braunschweig, Vieweg).—Tables for Quantitative Metallurgical Analysis: J. J. Morgan (Griffin).—Royal Uni- versity of Ireland Exam. Papers, 1898 (Dublin).—Year-Book of Photo- graphy (9 Cecil Court).—A Country Sehnolmsten: James Shaw, edited by Prof. R. Wallace (Edinburgh, Oliver).—I Batteri Patogeni: Dr. N. Ottolenghi (Torino, Rosenberg).—Sieroterapia e Vaccinazioni Preventive contro la Peste bubbonica: Dr. A. Lustig (Torino, Rosenberg).—The Elements of Practical Astronomy: W. W. Campbell, 2nd edition (Mac- millan).—Bergens Museum. Report on Norwegian Marine Investigations, 1895-97 : Hjort, Nordgaard, and Grann (Bergen).—Iist of the Genera and Species of Blastoidea in the British Museum (Natural History) (London), —Chimie Végétale et Agricole: Prof. Berthelot, 4 Vols. (Paris, Masson).— Sewer Design: H. N. Ogden (Chapman).—The Steam Engine and Gas and Oil Engines: Prof. J. Perry (Macmillan).—The Dog: edited by Piepe and Furneaux (Philip).—An Account of the Deep-Sea Ophiuroidea collected by the R.I.M.S. Ship /zvestigator: R. Koehler (Calcutta).— Traité Elementaire de Mécanique Chimique: Prof. P. Duhem, Tome iv. (Paris, Hermann).—U.S. Geological Survey, 18th Annual Report, Part 2, Part 5 (Washington). PampuHLets.—Die Methode der Variationsstatistik: G. Duncker (Leipzig, Engelmann).—Das Hypsometer als Luftdurckmesser, &c.: H. Mohn (Christiania, Dybwad).—Summary Report of the Geological Survey Department, 1898 (Ottawa).—Mauritius Magnetical Reductions: T. F. Claxton (Mauritius).—Protokoll iiber die yom 31 Marz bis 4 April, 1898 zu Strassburg i.E. abjgehaltene erste versammlung der Internationalen Aéronautischen Commission (Strassburg).—Picture Taking and Picture Making (Kodak Press).—Natural History of the Musical Bow: H. Balfour, Primitive Types (Oxford, Clarendon Press).—Thatsachen und Auslegungen in Bezug auf Regeneration: A. Weissmann (Jena, Fischer).—La Naviga- tion a Vapeur sur le Haut Yang-Tse: R. P. S. Chevalier (Chang- Hai). SeERIALS.—Journal of the College of Science, Imperial University of Tokyo, Japan, Vol. xi. Part 2 (Tokyo).—Proceedings of the Washington Academy of Sciences, Vol. i. pp. 15-106 (Washington).—Johns Hopkins University, Studies in Historical and Political Science, Series xvii. Nos. 4 and s (Baltimore) —Monthly Weather Review, February (Washington).— Boletim do Musen Paraense, December (Para).—Societ&a Reale di Napoli, Atti della Reale Accademia delle Scienze Fisiche e Matematiche, serie ii. Vol. ix. (Napoli).—Contemporary Review, June (Isbister).—Century Magazine, June (Macmillan) —Humanitarian, June (Duckworth).—Photo- gram, June (Dawbarn).—Knowledge, June (Witherby),—Journal of the Chemical Society, June (Gurney).—Journal of the Marine Biological Association, June (Dulau).—Middlesex Hospital Journal, May (London).— Zeitschrift fiir Physikalische Chemie, xxix. Band, 1 Heft (Leipzig).— Journal of Botany, June (West).—Madras Government Museum, Bulletin Vol. 2, No. 3 (Madras).—An Illustrated Manual of British Birds: H. Saunders, 2nd edition, Parts 16 to 20 (Gurney.)—Fortnightly Review, June (Chapman).—Scribner’s Magazine, June (Low).—Anglo-American Maga- zine, June (Anglo-American Publishing Company). CONTENTS. PAGE Man; Past ‘and Presentua byte. lz. |. >. +.) see Practical Geometry. ByiGeS.Ma =. ~ .s) «suena Our Book Shelf :— Thompson: ‘* Michael Faraday: his Life and Work???) 0.70.2 aero 8 Re er Biitschli: ‘* Untersuchungen iiber Strukturen.”— iA. M.. 2). s, yeaa) ose 6) Gee Reed Quinn: ‘‘ A Manual of Library Cataloguing” . . . 124 Letters to the Editor :— Strawberry Cure for Gout.—F. G. ....... . 125 Distant Sounds. —W. F..Sinclair . ...... . 125 The Jubilee of Sir George Gabriel Stokes. (///us- brated.) 9...) CERISE Sey os”... eee Centenary of the RoyalInstitution. ...... 129 Lhe Height. ofthe Auroratege << toc: -, -) see gO The Total Eclipse of the Sun, May 1900 . . . . . 133 Notes. (///ustrated.)} RECON io, © 133 Our Astronomical Column :— Gomet-1899) a \(Swift)ige seem ewe ces 136 The Royal Observatory, Greenwic oe | LS eS 6) Spurious Earthquakes. (W2zth Diagram.) By Dr. Charles Davison’. geen een aah -sis + seo Report of the London Technical Education Board 141 University and Educational Intelligence 141 Societies and Academies. (///ustrated.) . 142 Diaryjof, Societies. 4 syeesuenene Ee ees 3 eS Books, Pamphlets, and Serials Received... .. 144 5 NATURE 145 THURSDAY, JUNE 15, 1899. THE ANTHROPOLOGY OF BADEN. Zur Anthropologie der Badener; Bericht tiber die von anthropologischen Kommi*ssion des Karlsruher Alter- tumsvereins an Wehrpflichtigen und Mittelschiilern vorgenommenen Untersuchungen. By Otto Ammon. Pp. xvi + 707. Maps 15. (Jena: Gustav Fischer, 1899.) OR many years the distinguished worker, Dr. Ammon, has been conducting an anthropological survey of the Grand-duchy of Baden in such an ex- haustive and detailed manner as cannot fail to excite the admiration of all interested in this branch of science. A considerable proportion of his investigations has been already published and incorporated in anthro- pological text-books ; but the present bulky volume gives the whole of his work in collected form, and embodies such generalisations as he considers can at present be safely attempted. For the final bearings of these in- vestigations on the history and evolution of this portion of the Caucasian race, Dr. Ammon states, however, that further observations are necessary both in his own and in neighbouring countries. As a monument of patient research, many of the fruits of which others will pluck, the volume before us reflects the highest credit on the author and his fellow-worker, Dr. Wilser. The observations have been carried out on recruits and school-children ; the two series being kept quite distinct from one another. The country has been mapped out into districts, which were assiduously worked from 1887 to 1894, three out of the four chief districts having been undertaken by Dr. Ammon himself, while the fourth has fallen to the lot of Dr. Wilser. The number of in- dividuals (which is very great) examined in each of the four districts is clearly indicated on the first of the admirable series of maps, which render both the physical features of the country and the results of the survey conspicuous at a glance. In view of the general gradual numerical diminution of blonds and the increase of brunettes as we pass from North to South Germany, Baden, as forming a long narrow strip running from the south towards the centre of the German empire, is admirably circumstanced to display the development of this law in the southern provinces. In addition to describing the ordinary physical features of the country, the geological structure is likewise taken into account ; and the effects of all natural surroundings on the population are thus considered in full detail. To enumerate all the anthropological features which have entered into the scheme of survey would be wearisome ; and it must suffice to say that bodily stature (subdivided into total length, sitting-length, and leg-length), the pro- portions of the length to the breadth of the head, the colour of the eyes.and hair, and the development of hair on parts of the person other than the scalp, are all taken into consideration. . Especial attention is directed to the difference in the anthropological features of the inhabit- ants of the rural and urban districts ; and, above all, to the changes in the population of the latter induced by immigration from the former. In these investigations, NO. 1546, VOL. 60] Dr. Ammon lays claim to having founded a new branch of anthropology. Seeing that to render adequate justice to the scope of the work would require a considerable portion of a number of NATURE, it will be advisable to concentrate attention on a few features. Among these, the relative prevalence of long-heads and round-heads, of blonds and brunettes, in different districts is perhaps the most generally interesting. At the commencement of the second section of the work we find some theoretical observations on the three “primitive” types of man met with in Europe. In common with many other modern anthropologists, such as Ripley and Sergi, the author recognises, firstly, the Mediterranean long-heads, of medium or small stature, with dark eyes, hair, and skin. Secondly, the North European long-heads, of tall stature, with blue eyes, blond hair, and fair skin. And, thirdly, the Alpine round-heads, whose stature is medium, with dark eyes, hair, and skin. And here it is important to notice that the author speaks of these simply as /yZes, in contra- distinction to vaces. He further observes that, owing to crossing, neither of the three types are common in their original purity in any district. In Baden itself, the population at the present day seems chiefly due to a mixture of the fair North European long-heads with the dark Alpine round-heads, the dark Mediterranean long- heads having failed to penetrate so far north in any great numbers. The following table shows the number of individuals of each type met with among different classes of the population : Immigrants. Town-born. b Rural ——— ~ = Type: districts. Small Large Small Large towns. towns. towns. towns. North European 146 4 II 27 15 Alpine 26 BIO Sweet th mare pel Mediternanean ae 9 to) oO fo) of The percentage from these works out as below :— North European 1°45 OFF eeelie bien LaQA aed 254 Alpine 0°39 0°93 ... OO! OBS. 0127 Mediterranean 0°09 fe} fe} fo} 0705 From this we see that, while among the immigrants the North European type is rarer in the small and the large cities than in the rural population, among the town- bred the percentage rises so as to exceed that of the rural districts, this being most markedly the case in the large cities, where we have 2°54 per cent., against 1°45 in the country districts. Respecting the Alpine type, we find the immigrants into small towns standing at 0°93 per cent., and at o'g1-in the larger cities, as against 0°39 in the rural districts ; whereas in the town-bred class the percentage is less than in the country districts, the diminution being most marked in the case of large cities. Here, therefore, we have evidence that the blond long-heads tend to gravitate towards the large cities, where they flourish ; and that while there is also a large immigration of the dark round-heads, yet that these tend to die out in their urban homes. Certain details are also viven with regard to the position occupied by the dark round-heads among their fellow-students in the schools ; but into these it is impossible to enter on this occasion. H 146 NALORE [JUNE 15, 1899 To a certain degree, these results accord with those arrived at by Monsieur de Lapouge in France, that anthropologist contending that the enterprising, restless, long-heads migrate in disproportionate numbers from the rural districts to the cities, where, however, they eventu- ally tend to die out. As regards this dying-out, so far as the blond long-heads are concerned, Dr. Ammon’s figures do not appear to accord with the French con- clusions. And having regard to the objections which have been urged against the latter, our author is wise in stating (in the preface) the necessity of further in- vestigations before definite deductions are attempted. He, however, thinks it quite possible that a “selection of long-heads” may be taking place; and expresses the “pious wish” that such may prove to be the case. As regards the contention of the French investigator that the dark Mediterranean long-heads are the type best adapted for an urban existence, where they choke out the long-headed immigrants, Dr. Ammon! considers that this is not supported by the results of his own work; this showing a total absence of the Mediterranean type in three out of the four urban districts, while in the fourth they are considerably less numerous than in the rural districts. Pursuing the same subject, we find, in the fourteenth chapter of the second part, Dr. Ammon giving a series of interesting details with regard to the differences of skull- proportion and hair-colour between the sons of the immi- grants into the towns and those of their native-bred inhabitants. From these it appears that in the smaller towns the sons of town-bred people exceed those of immigrants both in stature, sitting-height, and length of leg, as well as in the leg-index. In large cities, on the other hand, while the first three factors in the former show a similar increase over the country-breds, the leg- index is less. From the country population to the immigrants, from the latter to the sons of immigrants, and from these again to the sons of the city-dwellers there is an increase in the number of long-heads, with a proportionate diminution of round-heads. In both generations of the town-breds the relative number of blue eyes at first increases and then diminishes in cities of all sizes ; in small towns the number of per- sons with blond hair does the same, while in large towns it remains constant. In the town generation the North European and the Alpine types tend to converge, and the Mediterranean type to disappear. It is in consequence of these changes that a preponderance of blond persons is not observable among the recruits drawn from towns. Although the above are only a few of the interesting results of the author’s investigations, it will be evident that they are of the utmost importance in regard to current French theories as to the general inferiority of the round-heads, and their absorption in cities of the superior long-heads. But, as even the mental superiority of the latter over the former type is by no means ad- mitted by all anthropologists, it is evident that we are at present only on the very threshold of studies of this nature. That results likely to be of real service in con- nection with the problems presented by urban and rural 1 Page 448. It isa little difficult to reconcile Lapouge’s statement as to the dying out of long-heads in cities (see Keane's ‘‘ Man, Past and Present,” p- 520) with his contention that the Mediterranean long-heads show a special suitability for such an existence. NO. 1546, VOL. 60] populations, especially those connected with the present preponderating increase of the former, will ensue from the steady pursuit of such studies, can but be the earnest hope of all those interested (and who is not ?) in the future of the higher branches of the human race. Rows LIMNOLOGY. The Microscopy of Drinking-Water. By G. C. Whipple, Biologist and Director of Mount Prospect Laboratory. Pp. xii + 300, and plates. (Brooklyn, N.Y.: Wiley and Sons. London: Chapman and Hall, Ltd., 1899.) Examination of Water (Chemical and Bacteriological). By W. P. Mason, Professor of Chemistry, Rensselaer Polytechnic. Pp. 135. (New York: Wiley and Sons. London : Chapman and Hall, Ltd., 1899.) | Dien is an example of a class of books in the pro- duction of which the Americans are bidding fair to take a lead, the type of book which may be termed the popular practical scientific manual, where the limit- ation of the subject-matter and the thoroughness of treat- ment aimed at are worthy of the German, but devoid of that hair-splitting exactness which so often leads to obscurity ; while the general style and breadth of treatment are essentially English, and at the same time are saved from the superficiality too common in native technical treatises, by the industry and original ability of the energetic American. At the same time, the present work is not devoid of a certain diffuseness, which we think is referable to the author’s enthusiasm leading him into disquisitions too long for the proper purpose of the book, but which is possibly the more marked to us because he is writing about American waters in par- ticular, and about conditions not known in England. The title may seem to many to claim too much ; for Mr. Whipple puts aside at the outset all that relates to bacteria, and takes a very wide view of “ drinking-water.” He regards the subject of the examination of water as divisible into (1) Physical examination. (2) Biological examination. (1) Microscopical. (2) Bacteriological. (3) Chemical examination. A mode of classification which lands him in some incon- sistencies—for some Schizomycetes are dealt with later on—and would vitiate the work if it were not clearly set forth that he is concerned solely with that part of the microscopical examination of water which is not bac- teriological in the accepted sense of the word, and comes under the head of Limnology, dealing with those organisms which can be filtered out by means of fine- meshed nets or coarse filters incapable of keeping back water-bacteria. The position reminds us of Miss Kingsley’s diatribe against the utility of filters in West Africa. “A good filter is a very fine thing for clearing drink- ing water of hippopotami, crocodiles, water snakes, cat- fish, &c. . . . ; but if you think it is going to stop back the microbe of marsh-fever—my good sir, you are mistaken.” Mr. Whipple, however, does not attempt to stop the smaller organisms by his filters, but only deals with the JUNE 15, 1899] larger ones, and having laid down his position, he pro- ceeds to show, by his own interesting treatment of the theme, how large and important a subject that of limnology is, and how much neglected it has been in spite of the vast amount of information scattered in detail through the scientific literature of Europe. Diatoms, Cyanophycee, Green Algze, Fungi, and larger Schizomycetes, Protozoa, Rotifera, Crustacea, Polyzoa, Sponges, and miscellaneous higher aquatic plants and animals are dealt with in detail, and very interesting particulars are given of their numbers, distribution, and seasonal abundance in lakes and rivers, as well as many _ of their biological peculiarities. Probably few people are aware that some of these small organisms contain powerfully odorous oils, and are re- opportunities. sponsible for the strong and unpleasant smell of certain waters, quite apart from decomposition, We think, in spite of the many interesting facts regard- ing the existence of thermophilous organisms, the biology of blue-green algze, &c., the author has missed some For instance, we find no discussion or even mention of that puzzling phenomenon, the “ Break- _ ing of the Meres,” although some of the organisms now known to be concerned—Anabaena, Aphanozomenon, &c. —are referred to. Again, it seems surprising that no reference occurs to the important 7d/e of such organisms as Phormidium in building up “ Tufa,” “ Travertin,” and other calcareous and siliceous substrata, particularly as some of the most striking examples occur in the United States. Prof. Mason’s little book proposes, if not protests, too much, as it is manifestly impossible for any author to cover the ground implied in the title in 126 small octavo pages of large print; and although we may give him credit for clear writing, an excellent selection of materials, and a general “up-to-date” style of presentment—includ- ing modern tables and charts—we cannot recommend this gossip about the chemical examination of water, with a smattering of bacteriological methods, as a serious text- book for students. On the other hand, we do commend it to the would-be writers of similar books in this country as indicating some of the new directions in which such writings should depart, and so abandon the too well-worn grooves in which our present bacteriologists are creeping onward. Is not “ Wolffhiiggle,” on p. 107, a misprint for Wolff- hhiigel? It recurs on p. 108. HEART AND SCIENCE. Kritik der Wéssenschaftlichen Erkenntniss. H. vy. Schoeler. Pp. viii + 677. mann, 1898.) FRIEND of Dr. v. Schoeler’s died a victim to his devotion to science, when too late he had reached the conviction that his jealous mistress was not worth the sacrifice he had made for her. What, then, asked v. Schoeler, are the data, what the results of science and philosophy ? How shall we free ourselves from their obsession, and make them servants rather than tyrants ? Is ethical nihilism the upshot and a pessimism subversive of human endeavour in all directions other than the in- tellectual? Has Nietzsche, after all, the right of it? NO. 1546, VOL. 60] By Dr. (Leipzig : W. Engel- NATURE 147 Dr. v. Schoeler answers these questions in the present volume at, perhaps, inordinate length, overloading his work with quotations and instances not always quite relevant to his point. He essays nothing short of a critique of philosophy and of the natural sciences and a constructive theory of life without assumptions. In this task his performance is necessarily very unequal in different sections. His chapter on the ancient philosophy, for instance, is a not very valuable contribution to the history of anticipations. Parmenides is a “Schelling of antiquity,” but this does not prevent Heraclitus being called in as a forerunner of the /dentitats-philosophie, and the account of Aristotelian science goes little, if at all, beyond what can, be learned from G. H. Lewes. On the other hand, where he is more at home and possesses a more living interest, our author’s criticisms, if rambling, are often to the point. It is, however, not always quite easy to determine what is intended as mere exegesis, what is the expression of v. Schoeler’s own view. His philosophical sympathies lie on the whole with Kant, interpreted not as containing Idealism of the Hegelian type in germ, but as frankly realistic, relativist, even agnostic. His master is the Kant of the anti- nomies, and of the unknowable Ding-an-sich, treating “freedom” as an ideal amid phenomenal determination. He also has a word of praise for the doctrine of monads, leans a little to Schopenhauer, and accepts the results ot evolutionist biology and psychology, though critical of the extent to which they solve ultimate problems, and prepared with Kant to admit the teleological judgment with the limited and relative range allowed it in the third critique. In the scientific field, his interests seem to be mainly what may be termed biological in the wider sense. The smallness of the results of science in general, how- ever frankly we may admit those results, and the little advance made by either philosophy or science towards the solution of ultimate problems, leads to a provisional relativism almost sceptical. But pure scepticism is ne- gated by the facts of life, and if we reject mechanical constructions as dogmatic, and shrink on our spiritual side from the issue of all dogmatisms and positivisms, and, indeed, of all -isms, in the insanity of Nietzsche, we need to find an escape. Such an escape, v. Schoeler holds, is not provided oy religion. It must be sought for in the idea of humanity, and the furtherance of its ideals in art, in the ethics of family life, and in work in the cause of society. That this earth may or will be dissolved with its phantasmagoria of human knowledge, human passions, human needs, human ideals, lies perhaps not obscurely among the teachings of science. But this pessimism is not subversive of effort and aspiration, so long as it does not despair of the commonwealth. There is no absolute, neither god, nor world, that we can know in other than a relative sense or with other than a relative value, for they have no existence other than a relative one. The advance of the new outlook for the beginning of the twentieth century consists in freeing men from an illusion or a madness, in a new and undogmatic positivism or relativism without pride of intellect, and with a soun hold upon purely relative ideals through the zsthetic and the ethical emotions. 148 Intellectualism is the curse under which the author’s friend fell, a martyr going at the last unwilling to his fate. To this we owe the degeneration held to be typically fiz de séécle. We must meet the danger, exor- cise the curse, by derogating from our claim to construe an absolute, and entering instead upon our heritage as men. “ The Ideality of the life of feeling is the remedy.” Dr. v. Schoeler is undoubtedly fitted to write the history of philosophical and scientific ideas in certain fields. His chapter on matter, and his section on the achievement of nineteenth century surgery prove this. And his general power of appreciation and range of interest carry him a long way towards the adequate treatment of his encyclopedic task. But his rhetorical tendencies, shown, for example, in his interesting chapter on Nietzsche, and his exuberance, give the book an ineffectiveness which a smaller work might escape. And there is no index to a critique of all philosophy and all science, though laden on every page with citations ! H. W. B. OUR” BOOK SHELF. Les Plantes Utiles du Sénégal—Plantes Indigénes— Plantes Exotiques. Par Le R. P. A. Sébire. Pp. Ixx + 341 (Paris: J. B. Bailliére et Fils, 1899.) RAPID strides have been made of late in opening up to commerce the several European possessions on the West Coast of Africa, and though much has already been done so far as vegetable products are concerned, only a small percentage of such products find their way regularly into European commerce, such, for instance, as palm oil, ground nuts, rubbers, chillies, and a few drugs, including kino, cinchona bark (introduced), strophanthus seeds, kola, &c. With regard to timbers, there is a wide field for development, as there are many valuable woods in the forests that should find a ready market in Europe. African mahogany, afforded by Ahaya senegalensis and other trees, is regularly imported into Europe, the trade in this timber having, during the last decade, increased enormously, and though it may lack the figure of Central American mahogany, it commands a ready sale in European ports. Taking into consideration all these facts, any contribution, however small, of the nature of the book under review must be accepted with thanks, so long as the facts and figures are trustworthy. In the preparation of the work the author’s aim has been to provide those engaged in agricultural pursuits, or in the development of the vegetable economic resources of Senegal, with a manual of useful instruction. The book affords detailed information on indigenous plants, those that have become acclimatised, and further with those recommended for experimental cultivation. The first forty pages deal with such subjects as the seasons, water supply, soils, injurious insects, &c., and is followed by a list of exotic economic plants culti- vated in the country, with notes on the results obtained, the plants being classified according to their uses. Synoptical tables follow of generic and native names, together with a list of medicinal plants, arranged accord- ing to the diseases in the treatment of which they are employed. The main portion of the book, covering 300 pages, consists of a list of plants arranged under their respective natural orders, with scientific and native names and details bearing upon their properties, uses, and distribution. This portion of the work contains much valuable information, and bears evidence of zeal in its preparation. Besides dealing with indigenous and acclimatised plants, notes are given on various exotics NO. 1546, VOL. 60] WAT ORE. [JuNE 15, 1899 and their uses with the view to their introduction into the Colony, or as an aid in determining the properties of indigenous plants upon the assumption that allied species in a given natural order possess similar properties. This is an excellent idea, and adds to the usefulness of the work. An index of Latin and French names, together with lists of native names, complete the work. In a book of this description, written on the spot, one naturally expects to find errors. The scientific names in many instances are obsolete or incorrectly spelled, and due care has not been exercised in the introduction or omiis- sion of capital letters, italics, &c. It would have been much better had the information been concentrated under fewer heads, and a good general index of scientific and native names combined would have added to the utility of the book. This may be remedied in another edition, but as the work now stands it can be recom- mended with confidence to those engaged in the develop- ment of the vegetable resources of Tropical Africa as a very useful addition to the limited number of such books already existing. Many illustrations of interesting sub- jects are intercalated in the text. J. M. HILLIER. Applied Geology. By J. V. Elsden, B.Sc. (Lond.), F.G.S. Part II]. Pp. vi+ 250, with 186 Figures. (London : “The Quarry” Publishing Co., Ltd., 1899.) THE first part of this work was noticed in NATURE, vol. lviil. (1898), p. 615. The second part consists of eleven chapters and an appendix. The first chapter (Chapter vi. of the work) deals in 19 pages with un- stratified ore deposits. In the following chapter (vii.) the occurrence of the non-metalliferous minerals is described. We have, for example, 2} pages on coal, 1 on petroleum, and 1 on diamonds. As these pages include the illustrations, it is clear that the amount of information is completely out of proportion to the importance of the subject. No doubt the author would plead the lack of space for more, but surely in that case he should have made a judicious selection of the literature bearing on the subjects in question, and given full references to it. The same remark as to the almost complete absence of references applies to the book as a whole. Not only would such references have rendered useful short sketches of great subjects, which, standing alone, are almost useless, but they would have given the weight of authority for many statements which, un- supported, appear dogmatic. Chapter viii. is devoted chiefly to prospecting, developing, bed-mining, and vein-mining. The next four chapters deal with “Building and Ornamental Stones.” They are chiefly illustrated by sixteen drawings of microscopic rock sections, clearly executed but without any indication of the amount of magnification. On. p. 76 the igneous rocks are classified into three groups—Plutonic, In- trusive and Volcanic; but it by no means follows, as there stated, that intrusive rocks are microcrystalline, still less that volcanic rocks are necessarily partly or entirely glassy, nor is it logical to classify serpentine as intrusive, while peridotite, of which most serpentines are merely altered examples, is termed plutonic. Rocks used in the arts and manufactures are described in Chapter xiii. Engineering geology, especially the subjects of water-supply, embankments, tunnels and cuttings, occupies Chapters xiv. and xv., and the final chapter is devoted to surface features such as soils. In an appendix are given “simple rough methods for the determination of minerals and rocks,’ and there is a good index. The work is very readable, well illustrated, and suited for geological students who wish to learn some of the applications of the science. The practical man will also gain useful hints, though he will feel rather at sea in reading some of the petrographical descriptions, and will wish for more details or references on many practical points. JUNE 15, 1899] NATURE 149 On Buds and Stipules. By the Right Hon. Sir John Lubbock, Bart., M.P., F.R.S.,D.C.L., LL.D. With four coloured plates, and 340 figures in the text. Pp. xix + 239. (London: Kegan Paul, Trench, Triibner, and Co., Ltd., 1899.) THE new volume of the “International Scientific Series” forms a welcome addition to those already published, and it will be read with interest by all who are drawn to a study of the natural history of plants. For although accounts of bud-protection, &c., are to be found scattered through various journals, there existed no connected story of the numberless artifices by which plants shield their winter buds before the appearance of Sir John Lubbock’s book. Naturally much of its contents in- cludes matter of common knowledge to those botanists who care for the study of the living plant, but even for them there is much which will be probably found to be novel, and at any rate well worth reading ; whilst the freshness and first-hand character of the recorded observations affords a pleasure which those who are acquainted with the author’s previous essays in natural history will naturally expect to enjoy from a perusal of the work. It is refreshing to observe that Sir John has not allowed himself to be trammelled too much by orthodoxy—to find that, for example, he declares for the stipular nature of the outgrowths on the petioles of the early leaves of the flowering currant. In the account of the stipules in the genus /7opfaeo/um, however, there seems to be no mention of the interesting fact that the first two leaves (following on the cotyledons) in the common “nasturtium” are stipulate, whereas these structures are absent from the later developed leaves. Indeed, the whole genus seems worth a more extended treatment from the point of view of stipulation, afford- ing, as it does, almost all transitions from complete development to a complete arrest of stipular formation, and these facts are of especial interest in view of the stipulate character of allied forms. The tendrils of sarsaparilla and also the ligule of grass leaves are considered, and probably with justice (at least as regards the former), as of supular nature. The beautiful arrangements by which buds are pro- tected by means of developments of the axillant leaf, as in the plane, maple, AAws, Kalmia, &c., are de- scribed and well figured ; indeed, the excellence of the numerous drawings forms by no means the least welcome feature of the book. Space forbids us to do nore than thus briefly indicate a few of the points contained in the volume, which is a most ‘valuable contribution to the literature of a fascinating subject. Vo, 18 38 The Philippines and Round About. By Major G. J. Younghusband. Pp. xiv + 230. (London: Mac- millan and Co., Ltd., 1899.) IN this amusing and well-written book the author gives a very good description of the towns of Iloilo and Manila. The volume is the result of a short visit made soon after the Spanish-American war, of which we get an excellent account. The life and customs of the inhab- itants of the Philippines are well described, and the reader cannot fail to be surprised at the slow progress civilis- ation has made in those parts. This fault is due, with- out doubt, to the bad condition of the Government. The only outcome of centuries of authority is an absolute want of national discipline. The Filipinos, far from being down-trodden by all the oppression and cruelty they have endured, are lazy and insolent ; but, perhaps, this is not altogether surprising seeing that no wholesome authority has been used. The author has been more interested in incidents of travel than in the natural history of his surroundings. There seems to be little domestic comfort in hotels | or houses, and we, who realise so well the value of scientific appliances, cannot fail to be forcibly struck with NO. 1546, VOL. 60] the descriptions of the primitive state of the sanitary arrangements of the towns. pihe book is a valuable addition to works of travel, and will be found a useful guide when visiting the Philippines and their neighbourhood, for good descriptions of life in Java and in the town of Saigon are also given. The Slide Valve Simply Explained. By W. J. Tennant, A.M.1I.M.E. (London : Dawbarn and Ward, Ltd.) THIS little pamphlet of sixty-five pages, forming volume No. 2 of the “ Model Engineer Series,” was originally intended to help the author’s railway students towards the attainment of clear general notions upon the subject of the slide valve. The author conceived the idea of using on a base-board a rotary disc to represent a crank- shaft, together with the idea of obtaining concentric circular diagrams of results, by using a crank-arm marked on the disc as an index-finger, and recording on the base-board the beginnings and ends of the arcs swept out by the crank in the various distribution-periods. For students with little or no geometrical knowledge the book should be most useful. We think, however, that a student’s time would be better employed in acquir- ing a sufficient amount of geometry to understand the Zeuner diagram, by aid of which the action of the slide valve can be represented more simply, quickly, and con- veniently than by the author's disc diagrams. ADS: LETTERS TO THE EDITOR. [The Editor does not hold himself responsible for opinions ex- pressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscrepts intended for this or any other part of NATURE. No notice is taken of anonymous communications. | Expansion cf Solids by Heat. THE following simple apparatus for showing the expansion of metals by heat may interest your readers. A cork rests on the table and is kept steady by two horizontal knit- ting-needles fixed into it. A third knitting-needle fixed in the cork stands () ) in an upright position, and } carries a second cork at itstop. Another knitting- needle passes through this cork and projects vertically downwards into a glass of water, and carries a third cork at its lowerend. This last cork carries a sewing- needle with its point pro- jecting upwards just above the surface of the water. If one of the vertical knit ting-needles is heated with a match, the point of the sewing-needle will disap- pear below the surface of the water; if the other is then heated, the point will appearagain. These small movements can be easily seen by watching the re- flection of a bright object in the surface of the water. Horace DaRWIN. The Orchard, Huntingdon Road, Cambridge, June 3. Bessel Functions, So Mr. A. B. Basset (p. 101) interdicts all such expressions as Armstrong guns, Whitworth lathes, Martini rifles, Boxer cartridges, Whitehead torpedoes, Corliss engines, Stemens steel, Thomson galvanometers, Peltier effect, Rontgen rays, hundreds of which are in common use among engineers, physicists, and 150 NATURE [JUNE 15, 1899 mathematicians, to say nothing of the educated general public ! His task is only comparable with the historic one which Mrs. Partington set herself with respect to the Atlantic. Bangor, June 7. A. GRAY. Larve from the Head of an Antelope. In preserving the head of an old ¢ Hartebeeste (4. cokez), shot on March 31, I took from the nostrils a few hours after death some twenty large larvee, which I am now forwarding you for identification. ; On April 19 I found similar larve in the nostrils of an old 9 Wildebeeste (C. Zaza) ; but I think their occurrence in the heads of antelopes in this part of Africa must be comparatively rare ; as, though I have shot and preserved the heads of quite a number—including many Hartebeeste—I have not come across them in any other instance. I may add, no appreciable emaci- ation was shown by the animals from whose heads the larvee were taken. RICHARD CRAWSHAY. Kiu, Uganda Railway, British East Africa, April 29. THESE larve are those of a fly of the family Oestridz, and their structure, as well as their habits, shows them to be refer- able to the genus Oes¢vus, and to be allied to the well-known ‘* Sheep-bot fly,” or ‘‘ Sheep-nostril fly ” (Oestrzs ovzs). Brauer in his ‘‘ Monographie der Oestriden” (Vienna, 1863) mentions such larvee as having been found in three species of antelope, and describes two species of fly (O. varzolosus, Low., and OQ. clarkzi, Shuck.) from South Africa, both probably parasitic on antelopes. Probably a search through the scattered literature since Brauer wrote would bring to light the record of other species of Oestrus with similar habits ; but, unless the flies were bred from the larvee, which would not be very difficult, the species con- cerned could not be identified. WaLtTeR F. H. BLANDFORD. 48 Wimpole Street, London, June 8. Walrus. FERDINANDO VERBESTI (1630-1688), in his work in Chinese, “ Kwan-yu-wai-ki” (Brit. Mus. copy, 15,297 a, 6, fol. 10, a), sub, ‘* Marine Animals,” relates thus : ‘‘ The Zoh-sze-ma is about 40 feet long, with short legs, and staying at the bottom of sea comes to the surface very seldom. Its skin is so hard that even swords are unable to pierce it. It has on its forehead horns re- sembling hooks, with which it hangs itself on a rock, thus sleep- ing a whole day without slightest awaking.” With all deference to Prof. G. Schlegel, who takes the animal here described for the Narwhal ( Zoung Pao, October 1894, p. 370), I will bolden myself for truth’s sake to state that the walrus is meant herein, Loh-sze-ma being only a Chinese rendering of Aosmar, the Norwegian name of the walrus. The main parts of this descrip- tion agree well with the description given by Olaus Magnus (‘‘ Historia de Gentibus Septentrionalibus,” Rome, 1555, p. 757), but not exactly—e.g., the latter author indicates the size of the animal by the words, ‘‘ maximos ac grandis pisces elephantis magnitudine ” ; while the former gives it more precisely, though much more exaggerated.! Can you or any of your readers oblige me by telling from what very source Verbesti derived his description ? Magnus speaks of the sleeping of the walrus hanging itself on rock with its tusks to be often so sound as to expose its life to danger. Similar story is told in Japan of the sun-fish (Ortha- gortscus mola), which is said to be floating asleep while its flesh and entrail are being removed (Kaibara, ‘‘ Yamato Honzo,” 1708, book xiii., fol. 43 4). KumaGusu MINAKATA. 7 Effie Road, Walham Green, S W., June 5. Strawberry Cure for Gout. IN connection with the letter of ‘‘ F. G.” in NaTuRE of June 8 (p. 125), on the strawberry cure of gout, I may mention that last year, when strawberries were so plentiful in England, a lady residing in Kent, who had formerly spent several years in Ceylon, where she had suffered from the wasting and often fatal com- plaint known as ‘* Ceylon sore mouth”? (the chief symptom of which is ulceration of the mucous membrane of the digestive 1 Gesner says: ** Alium esse puto qui _Rusvaal nominatur, quinquaginta passuum longitudine. . ” (Historia Animalum,” lib. IV., sd. ‘* De Rosmaro"’). NO. 1546, VOL. 60] organs), having had a return of the malady, and being unwilling to go abroad to undergo the ‘‘ grape cure,” conceived the happy idea to try strawberries instead, confining her diet to several pounds of these a day with plenty of milk. The remedy was so effectual that after a few weeks she was entirely cured of her malady, and had grown stout and well again. 5 Bedford Place, Croydon. DONALD FERGUSON. THE FRESH-WATER PEARLS OF AMERICA. qp ee production of pearls by numerous species belonging to the fresh-water bivalve family Uz7on- zdae has been a matter of common knowledge from time immemorial. Such pearl-bearing mussels occur in the Tay, Isla, and several others of the rivers of the British islands, as well as in many of those of the continent, Mesopotamia, China, and North and South America. As a rule, however, such fresh-water pearls, in Europe at least, are inferior in lustre, and consequently in value, to those obtained from the pearl-oyster; and in those British rivers which produce the pearl-bearing species of Uzo, it is stated that on the average one pearl is found in every hundred shells, and that only one pear! out of a hundred is fairly clear. During the eighteenth century, however, a considerable number of Irish pearls, ranging in value between 4/. and 1o/., were obtained, while one specimen, when mounted, realised 80/7. In Scotland, pearls worth from 3/. to 4/. each are not unfrequently found, and it is stated that as much as Joo/. has been paid for an unusually fine example. According to Dr. P. L. Simmonds, between the years 1761 and 1764 ten thousand pounds’ worth of Scotch pearls were sent to London, while in the corresponding decade of the present century the amount was considerably more than double that value. During the dry season of 1862, when the lowness of the streams rendered the fishing unusually favourable, more pearls were collected than in any previous year; and the average price consequently fell to fifty shillings, or less. Twenty years ago, when from 52. to 20/. was obtained for fine specimens, the general price was, however, much higher ; and one Scotch pearl, for which forty guineas was given, is the property of the Queen. British pearls were well known to the Romans, and it is probable that those from continental rivers were in demand at an equally early date. With the opening-up of the American continent by the Spanish explorers, the world was, however, flooded with a totally new supply of pearls, which there is good reason to believe were also of fresh-water origin. Wonderful are the accounts of the pearls found in the possession of the natives during the De Sota expedition from Florida to the Mississippi in 1540; and three centuries later Messrs. Squier and Davis disinterred vast quantities of damaged pearls from the ancient mounds of Ohio. So great was the number of pearls brought to light by these and other explorers, that it was considered improbable they could have been the products of the fresh-water unios of the country, and they were consequently believed to have been obtained from the pearl-oysters of the Pacific. In later years, however, many naturalists of repute were inclined to doubt the truth of this suggestion; and in an important and interesting memoir on the “ Fresh-Water Pearls and Pearl-Fisheries of the United States,” recently issued by the U.S. Fishery Commission, the author, Mr. G. F. Kunz, sums up the question as follows ; “ Not- withstanding the intercourse existing between remote Indian tribes, as shown by many authorities, and the fact that Pacific coast shells have been carried to Arizona, and that clam-shells have been found in Zuni cities by Lieut. Cushing, it is likely that these pearls came, not from the pearl-oysters of the Pacific coast, but from the marine shells of the Atlantic coast and the fresh-water shells of the eastern part of the continent. It is very probable that the Indians opened the shells to secure the animal as an article of food; that the shells of some June 15, 1899] NATURE 151 varieties, such as the common clam and conch, were made into wampum ; and that the pearls found in the shells were used as ornaments, whether lustreless pearls from the common oyster, or lustrous ones from the U77zo.” The opinion that these old pearls are of fresh-water origin is based on the fact that many of the North American rivers and lakes still abound with pearl-yield- ing Unionidae; and it is, therefore, the more remark- able that for over two centuries from the date of the Spanish exploration nothing seems to have been ascer- tained about the latter. As Mr. Kunz says, “the natives have been dispersed, and the white race, occupied with other interests and necessities, took little note of the hosts of fresh-water shells inhabiting the streams and lakes, and did not suspect their power of producing pearls. In the year 1749, John Winthrop, in a natural history catalogue, first mentioned the production of pearls by the fresh-water mussels of the country. But more than a century was destined to elapse before any prac- tical result arose from this knowledge ; for it was not till 1857, when the “queen-pearl ” was discovered at Notch Brook, near Paterson, New Jersey, that the country awoke to a conception of its hidden treasures. This pearl, which weighed 93 grains, was sold to the Empress Eugénie of France for 500/., and is said at the present day to be worth four times that sum. Its discovery immediately gave rise to an outbreak of “‘pearl-fever”; and the mussels of Notch Brook and other rivers were gathered by the million and ruthlessly destroyed, frequently with no pecuniary profit. So careless indeed was the mode of operation that a pearl weighing 400 grains, which would probably have proved the record specimen of modern times, was ruined by boiling the mussel in which it was contained. During the first year of the fever, the value of the pearls sent to New York was fully 3000/.; in 1858 it fell to about 4oo/., while from 1860-63 the yield was only 300/. for the whole period. Although there was some slight revival of the trade in 1868, when pearls were discovered in the Little Miami river, Ohio, it was not till 1876 that any important find was made. But in that year 600/. worth were obtained from Waynesville, Ohio, a locality which hast since yielded many more pearls, among them one of 38 grains weight, although of somewhat irregular shape. Since 1880 pearls have been found in districts further to the south and west ; Kentucky, Tennessee, and Texas becoming the chief pearl-producing States, while Florida has also contributed its quota. New Brunswick and Canada likewise entered into the competition, while in 1889 Wisconsin appeared on the scene with a large consignment of magnificently coloured pearls. Within three months more than 2000/. worth of these latter reached New York, including one specimen valued at over 100/,, the principal colours being purplish-red, copper-red, and deep pink. These finds led to intense activity among the pearl-hunters, with the result that the mussels were nearly exterminated in that district. Other parts of Wisconsin were found, however, to be equally prolific, and since 1889 it is estimated that pearls to the value of at least 5000/. have been obtained from that State alone. From exhaustion of the mussel-beds, the pearl excitement in the North-west subsided in the course of a few seasons. In 1897, the “fever” burst out anew in Arkansas, where it extended west into Indian territory, and north into Missouri, Georgia and certain districts in Tennessee being likewise affected. This period of excitement and activity promised to extend into 1898, of which year no accounts are at present to hand. A remarkable feature about the Arkansas discovery was the fact that a large proportion of the best pearls were obtained lying loose on the mud of the shores, or at the bottom of shallow waters, while sometimes they were found in or upon the soil at some distance from the water. “This peculiar oc- NO. 1546, VOL. 60] currence,” writes Mr. Kunz, “is partly explained by the wide extension of the waters in flood times over the low regions of the State, and by the shifting of streams and isolation of ‘cut-offs’; but the facts indicate further that under some circumstances, probably by agitation of floods and freshets, the loose pearls are lost or shaken out by the unios. A local impression prevails that the mussels ‘shed’ them at certain seasons. The fact that the pearls thus found were generally round and well-formed ; the aggregation in repeated instances of several or many near or together, and the non-occurrence of shells with them at these places—all point to the washing out of loose pearls from the unios, and their distribution by floods and freshets.” In 1897, the excitement appears to have had somewhat disastrous results in certain districts by abstracting the washers from their regular fields of labour. It has also caused a revival of pearl-hunting in other districts, notably in the neighbourhood of New York. Florida may at present be regarded as an almost unworked country; but, judging from the specimens hitherto obtained, will probably yield a rich harvest. The two largest and finest pearls at present collected from this State weigh respectively 68 and 58 grains, and realised 170/. and 120/. Connecticut has also witnessed a revival of pearl- hunting ; and here one of the collectors has started the German plan of using a pair of pincers to prise open the valves of the shells. The mussels that yield pearls in the States all belong to the typical genus U/#zo0, and include at least sixteen species. Most pearls appear to be obtained from the common U. complanatus, which is a very thick and rounded shell, shaped not unlike a Cyfrzza. Pearls are, however, occasionally found in thin and elongated species, like U. rectus. In the Amazon basin of South America, the pearl-bearing species belong to the allied genera Ayria and Castalia, while in China the pro- fitable species is a Dzfsas, and is much like the ordinary British Azodonta in general form. Unzo (Margaritana) margaritifera is the British pearl-mussel. With regard to the occurrence of the Arkansas pearls on the mud, it may be explained that the Unzonidae generally dwell in America on clear gravelly bottoms, and that in such situations the pearls when extruded from the shell would be ground up by the pebbles, or would be indistinguishable among them. Not so on the mud of the Arkansas streams, which seems to be the haunt of the unios. Whether the sup- position above mentioned, that the pearls are washed out or shed from the shells during life, be well founded, requires further investigation. It is stated that their non-association with shells is due to their having been washed away by floods or freshets after expulsion from the living animal; but this explanation would apply with equal force to the pearls yielded by defunct mussels. With a view of regulating the industry and preventing, if possible, the reckless destruction of mussels that takes place at each outbreak of the “ fever,” the U.S. Fish Commission commenced in 1894 an inquiry relating to pearl-fishing in the States; and the result of its labours up to 1898 is embodied in the report quoted above, the general conclusions being summed up as follows:—“‘The shells are most abundant in swift and clear waters, where the bottom is sandy or gravelly, and the country-rock calcareous. While still numerous in many streams, they have greatly diminished within a few years past, wherever the pearl-hunting enterprise has extended, and at some points are nearly exterminated. The pearls found are few, and those of marketable value represent the destruction of thousands of shells for every pearl obtained. . . . The methods of gathering the shells and extracting the pearls are the simplest and the most primitive, and the activity of a few 152 NATURE [JUNE 15, 1899 seasons generally exhausts the beds. This state of affairs | is one that loudly calls for reform. The wealth of unios that fills our rivers and streams is rapidly being destroyed | by ignorant and wasteful methods of pearl-hunting ; and | either some form of protection is important, or, if that be not possible, a wide diffusion of information as to better methods, and particularly the introduction of the tools used in Germany for opening unios far enough to see if there are pearls contained, without destroying the animal, which may then be returned to the water.” In the clearer streams of the country, the best method of collecting the mussels is by wading into the water armed with a water-telescope and a pair of spring nippers affixed to the end of a stick. The water-telescope | consists of a long, light, quadrangular tube open above, and shaped to fit the face (to which it is strapped), and closed below with a glass plate. Dressed in waterproof | clothing, the pearl-hunter wades along the bed of the | stream in a stooping posture, with the lower end of the tube immersed in the water, by which he is enabled to see the mussels on the bottom, and so to pick them out one by one with his nippers. Fresh-water pearls in general | are remarkable for their variety of tints, and nowhere is | | southern by that of Courmayeur. THE GEOLOGY OF MONT BLANC. M ONT BLANC and its aiguilles present some difficult problems to both petrologists and physical geo- logists ; problems, which, though they have something in common, are to a great extent distinct. The authors, however, have grappled with both. Their monograph, as a study of the petrography of the region, is full of valuable information ; but we think they have not been quite so successful in dealing with what it is now the fashion to call the tectonics. This portion no doubt contains much that is valuable, but the physical structure of the asszf of Mont Blanc has been treated too much as if the latter were isolated instead of being, as is | really the case, inseparable from the western and central part, perhaps even from the whole, of the Alpine chain. As most people are aware, the crystalline massz/ of Mont Blanc is defined by two well-marked troughs, occupied by rocks of secondary age, the more northern being furrowed by the valley of Chamonix, the more Each is bounded on the further side from Mont Blanc by crystalline rock, the former by the well-defined range of the Brevent and Fic. 1.—Contact of protogine with crystalline schist below the Aiguille du Midi. P, protogine; s, crystalline schists 3 Cc, contact. the variation more marked than in those from Wisconsin. Although white is the most common, almost any colour, from pink, purple, or red, to gold, bronze, and black, may be met with; while even a peacock-blue pearl is on record. The golden and wine-coloured specimens are presumably from the beautiful Uzo dromas, the only common species with a golden or yellow interior to the shell. Pink appears to be the colour most highly esteemed in America, next to which comes red, and then black ; but exceptional colours, like sky-blue, command exceptional prices. So far as shape is concerned, the first place is taken by spherical pearls, after which come hemi- spherical, or bullet-shaped examples, while oval cr pear- shaped specimens follow. As regards the maximum prices obtained for American pearls, the statements are somewhat conflicting and indefinite. It seems, however, | to be certain that a spherical pink pearl from Tennessee realised 130/., while a sky-blue pearl from Caney Fork, in the same State, was sold in America for 190/., and subsequently in London for 6607. With good luck, there | is therefore evidently money to be made by pearl-hunting in the American rivers. R. L. NO. 1546, VOL. 60] i} the Aiguilles Rouges, the latter by one or more varied character, and, generally speaking, of more bedded aspect. Of these two marginal crystalline zones, the northern is prolonged to the valley of the Rhone, where it crosses just below Martigny, after which it disappears beneath the sedimentaries of the Western Oberland. The southern passes on to join the Pennine chain to the east of Mont Blanc. The crystalline rock, however, which forms this and the rest of the central massif, is more or less fusiform in outline. (The term “amygdaloidal” applied by the authors seems misleading, as its connection with this structure is about equal to that of Monmouth and Macedon.) The central part of the szass//—though according to them not the very highest rocks of Mont Blanc—consists of a granitoid rock called protogine, formerly said to be composed of quartz, felspar, and talc, and to be the most ancient in the region. The talc is only biotite, more or less hydrous, and the rock intrusive 1 Recherches Géologiques et Pétrographiques sur le Massif du Mont- Blanc. Par Louis Duparc et Ludovic Mrazec. (Mem. de la Société de Physique et d'Histoire naturelle de Geneve.) Tome xxxiii. Ptie rre, we JUNE 15, 1899] NEAT LS B53 in the flanking crystallines. Profs. Dupare and Mrazec give an excellent account of the protogine ; its micro- scopic structure and its chemical composition. It isa granite, varying from moderately coarse to slightly por- phyritic, the silica percentage occasionally fallmg rather below that of an average granite. Enclosures of a more basic rock are found in it, which the authors consider, no doubt rightly, to be included fragments of more ancient material and not segregations. The age of this protogine cannot be exactly determined, but in other parts of the Alps a porphyritic granite, occasionally very coarse, yet bearing some resemblance to it, can be seen cutting the truly metamorphic rocks, called by the writer the “upper schists,” which apparently are the newest among the Alpine crystallines. The protogine is flanked on each side by a zone of mica schists and fine-grained gneisses, which accordingly must be older than it, and it includes occasional strips of schist. Of these, some may represent wedged-in fragments of the last-named zones, while others probably are dykes, modified by pressure. The affected by subsequent pressure. These are certainly later than the Carboniferous beds, and earlier than the lowest Lias, for they occur as pebbles in a conglom- erate of that age. lence these “porphyries,” like similar outbursts in other parts of the Alps, probably re- present Permian eruptions. The authors think them not impossibly connected with the vein granites, which would assign the latter also to about the same period. In discussing the “tectonics,” the authors give an excellent 7éswmé of the facts, so far as the immediate district of Mont Blanc is concerned, pointing out that the fan structure, of which this mass is generally considered to be a type, is not by any means so simple or so well developed as is generally supposed. They consider the central part of the chain to be a vast synclinal with minor secondary flexures between primitive anticlinals to the north and the south. According to one of them, a section across the range exhibits no less than eight anticlinal bands with intervening synclinals. On this view, we cannot venture to express a definite opinion ; we think, however Fic. 2.—Contact of protoxine with crystalline schists below the Aiguille du Midi, seen from the Montagne de la Cote. whole #zassif is traversed, in some places thickly, with veins of a fine-grained granite, poor in mica (aplite). The sedimentary rocks associated with the Mont Blanc massif belong to two distinct eras. One group occurs but locally ; the other has a wide extension, and perhaps was deposited over the whole breadth of this region of the Alps from north to south. The former group belongs to the Carboniferous period. It consists of conglomerates, often coarse, grits, and dark muds (now slates) ; the latter group forms part of the great Alpine Mesozoic series. At the base, Trias is found ; this, however, near the Mont Blanc masséf, is either feebly represented or absent. It is probably followed everywhere by beds of Rheetic age, but these often cannot be separated from the Lias. In parts of the Alps the series passes gradu- ally upwards into the Eocene ; in this district, however, nothing later than some portion of the Jurassic system is preserved. Here and there masses of “ porphyry” occur (one with, some without, free quartz), often much | NO. 1546, VOL. 60] ‘The schists are at the base of the Aiguille, and of a very dark colour. that at present a suspense of judgment would be prudent. But that the structure is far less simple than it was formerly represented to be can hardly be doubted. That great complications exist is not surprising, for the region, like the rest of the Alps, has been repeatedly folded. The authors recognise the following as the principal movements : (1) The Caledonian folding, during which the injection of the protogine occurred. This, we presume, so far as it can be dated, would be earlier Palzeozoic, perhaps post-Ordovician. Then came the Hercynian folding, which is supposed to have oc- curred in early Permian times, and to be connected with the ejection of the “ porphyries.” The axis of this folding ran slightly north of east. During the Mesozoic times, a subsidence continued, the mountains gradually dis- appearing, while deposition went on steadily. Then came the Tertiary movements, by which the present chain was formed. We cannot attempt to dis- cuss this part of the subject, for it is a complicated one 154 NATURE [JUNE 15, 1899 and the structure of the chain for a considerable distance to the south and the east must be taken into consider- ation. That great earth movements had preceded the Carboniferous period, and that mountains of a sort existed during it, and that this period was followed by very acute folding, are certain. We think, however, that the folds in this part of Europe (for reasons which have been published elsewhere) ran approximately from N.N.E. to S.S.W. Evidence of this may indeed be found in the district of which the authors are writing. Such flexures may have been the cause of the frequent trend of outcropping masses along almost the whole of the Alpine chain. During the Triassic period, as has often been observed, highlands, if not mountains, must have existed over more than one large area on the present site of the Alps, which afterwards disappeared beneath a wide- spreading sea. Then came the great Tertiary move- ments which formed the present chain. The authors apparently treat these as one, but most geologists hold that there were two epochs of maximum disturbance separated by one of comparative rest. The “ building ” of the present masszf and the neighbouring mountains should have been treated, we think, in greater detail ; for there is more than one interesting problem connected with the courses of the main streams, the positions of watersheds, and the localities chiefly affected by the -different movements, which are practically unnoticed. Still the memoir, as a whole, is a very valuable con- tribution to our knowledge of Alpine geology. T. G. BONNEY. THE BERLIN TUBERCULOSIS CONGRESS (1899).1 Il. (Section IV. Therapeutics. Section V. Sanatorium Treatment.) HE fact that 2000 doctors met together and discussed for two days the treatment, using this term in its broadest sense, of phthisis will, to the observant layman, be of evil omen. When a number of remedies or methods of cure for one disease are all guaranteed by their advocates as being efficacious, the attitude that one at once adopts is one of scepticism. How many doctors would meet together to discuss the treatment of primary syphilis, a disease which can be cured, and how long would it take them to do so if they did? Ina multitude of counsellors there may be wisdom, but in a multitude of treatments there is rarely a cure. The subject-matter of this Section was very fittingly opened by a paper of Dr. Curschmann’s (Leipzig) on the curability of phthisis. In the narrow anatomo-histo- logical sense, phthisis is rarely if ever cured; in the clinical sense, however, we can often accurately speak of a cure as having taken place, since the local signs in the lungs not only become arrested, but a certain amount of cepair takes place, and the attacked individual becomes practically normal. The majority of cases of cure, how- ever, are relative. In these cases, the local disease, although not coming to an absolute standstill, is of such a nature as to allow of the general condition of the patient remaining good. The congress listened with great attention to a paper read by Prof. Kobert, of Rostock, on the medical treat- ment of tuberculosis. The results formulated by the author were of especial value, since they were not con- fined to his own clinical experience at Gérbersdorf, but were derived from a series of inquiries addressed by him to general practitioners and lung specialists throughout Europe—2o0o0 in number. These specialists and prac- titioners had treated during 1898, the year to which the inquiry related, 50,000 cases of tuberculosis. The most interesting of these results are as follows: (1) that we 1 Concluded from p. 109. NO. 1546. VOL. 60] have in our possession no drug which exerts what may be termed a specific action in tuberculosis ; (2) that the early stages of phthisis can sometimes be met and cured without medicine of any kind; (3) in acute cases of phthisis, the fatal termination is neither avoided nor appreciably hindered by any kind of medicinal treat- ment; (4) that in the majority of cases of consumption medicinal treatment along with hygienic treatment is of the greatest possible use in allaying and easing cough, keeping up nutrition, and exerting a controlling action on the tubercle bacillus and its products. Dr. Brieger (Berlin) read a paper upon the treatment of pulmonary tuberculosis by means of tuberculine and allied methods. The author regarded Koch’s tuberculine as of distinct value in cases of pure pulmonary tuberculosis, asserting that in several cases an active tuberculous process had by its means been brought to a standstill. A valuable communication upon the climatic treatment of phthisis was made by Sir Hermann Weber ; but since this was reported at length in the British Medical Journal, no further mention will be made of it here. A paper of great interest was read by Dr. Dettweiler (Falkenstein), the subject being the hygienic, dietetic and sanatorium treatment of phthisis. Dr. Dettweiler, being the chief physician to one of the largest private sanatoria in Germany, spoke upon this subject out of the fulness of his experience. The author, after emphasising the fact that in phthisis we had to deal, not with a local con- dition, but a symptom complex, considered in how special a manner a sanatorium could meet the individual re- quirements of each case, and that by this means alone —viz., meeting every special want or symptom of the patient as it arose—could we hope to be successful in our treatment. It was not from open air, baths, exercise, alcohol, or feeding that we were to expect a “cure,” but from the co-operation each day, according to the state-of the patient, of all these means. Prof. Winternitz (Vienna) discussed the hydrotherapy of phthisis, and was followed on this subject by Dr. Carl Schitze. Dr. Holscher (Miilheim) read an interesting paper on the treatment of phthisis by guiacol carbonate and creosotal. The author, after giving a short 7véswé of the results of the continued use of guiacol, emphasised the fact that this method must be used in conjunction with forced feeding, especially in so far as concerns proteids. The guiacol is eliminated in combination with sulphur, and the sulphur thus used can only result from the breaking down of proteid material ; hence the importance of the strength of the patient being maintained by a plentiful supply of proteid material in the food. Dr. Cervello (Palermo) described his method of treatment, which con- sists in the inhalation of a formic aldehyde gaseous com- pound. Prof. Landerer gave the results he had obtained by the injection of cinamic acid (Zimmtsaure C;H;—CH =CH—CO,H) This substance, according to Prof. Landerer, acts by causing an increased leucocytosis, especially in the regions affected by the tubercular pro- cess. The action of many other antiseptics in tuberculosis was also considered, including iodoform and glycerine (Dr. R.' Hammerschlag) and Izal (Dr. Tunnicliffe), a few preliminary observations with the latter drug tending to show that it acted, as would be expected from its composition, similarly to guiacol and creosote. The serum treatment of tuberculosis was discussed by Prof. Maragliano (Genoa). This investigator’s interesting researches in this field have already attracted consider- able attention. The author, after having postulated from his own and Behring’s researches the existence of tuber- culous antitoxines and their presence in the blood of normal animals and man, stated that the quantity of these could be increased by injection. The injection of such antitoxines rendered animals partially or entirely immune to injections of tuberculous material, and lessened in man the reaction to tuberculine (Koch?). He further JUNE 15, 1899] affirmed that these “tuberculous antitoxines” had no poisonous action. Prof. Maragliano concluded by con- sidering the harmful influence of pregnancy upon phthisis, and recommended it, when occurring in a phthisical person, to be terminated artificially. Many other inter- esting papers, for which we cannot find room here, were read in this section. Section V.imSanatorium Treatment.—Since this tuber- culosis congress was the first of its kind, it is difficult, if not incorrect, to speak of any part of it as being a novel feature, but the relative newness of the sanatorium treat- ment of consumption rendered this Section the most in- teresting one of the whole congress. As these notes are intended for lay as well as professional readers, perhaps it would not be waste of time and space to discuss what is meant by the sanatorium treatment. It seems to the writer that all that is meant by sanatorium treatment is the placing of patients suffering from phthisis in its dif- ferent stages in an institution or house where they can be constantly watched by skilled doctors, and where every appliance for rest and exercise and amusement in pure and dry open air, forced feeding (“‘ubernahrung”), and hydrotherapy exist. So much has been said about open- air tréatment, Nordrach treatment, and so on, that the more general one’s remarks are here the better. If a personal name is to be attached to sanatorium treatment it ought to be that of Brehmer, whose book still remains the classic and, indeed, to all intents and purposes the only book upon the subject. If it is wished to label this treatment with the name of a place, it ought to be called the G6rbersdorf treatment, for there in Upper Silesia Brehmer founded his institution, and there it thrives to- day. It must always be remembered that open air is, although an important part, only a part of the whole, in- sistance upon the food question, and proper and suitable medicines, including alcohol, and above all, the adapt- ation of all these means to the daily and even hourly fluctuations of the patient, are essential factors in the sanatorium treatment. The subject matter of the Section was introduced by a paper of Prof. Leyden’s, who sketched the development of the sanatorium question. Herr Schmieden (Berlin) read a paper upon the building and arrangement of sanatoria. Dr. Schultzer (Berlin) discussed the arrange- ment, management and results of sanatorium treatment. The author reckoned the cost of a sanatorium for 120 beds at 3s. per diem per patient. He pointed out that the re- sults obtainable from treatment could be greatly improved by the construction of intermediate sanatoria, to which patients almost cured could go and get occupation while being still, to some extent, under treatment. Dr. Edward Kaurin gave an interesting account of the sanatoria for tuberculous patients in Norway. The largest sanatorium is situated on the sea coast, and apparently great attention is paid to diet, for each patient consumes more than two quarts of milk’ per diem, and about three ounces of butter, in addition to his ordinary meals. The cost per head is 1:20 kronen. Prof. Ewald treated the subject of sanatoria for children. Dr. Rufenacht Walters read a paper on the hygienic dietetic treatment of phthisis in Great Britain. The author emphasised the fact that open-air treatment, combined with increased diet, had long been practised in this country with success. He described shortly the hospitals, convalescent homes, &c., where this treatment had been followed. He pointed out the im- portance of the modern movement in this country for systematising the struggle against tuberculosis, and con- cluded with a few pregnant remarks concerning climate in the treatment of tuberculosis, and the necessity for improving the general mode of life of tuberculous patients. Dr. Sinclair Coghill made a communication upon the treat- ment of phthisis, in which he described the National Hospital for Consumption at Ventnor and the methods practised there. NO. 1546, VOL. 60] WATORE MG) Many other papers followed in this Section, giving the results at sanatoria situated in the most varied regions, and also discussing the difficulties to be met with and overcome in each country in impressing the hygienic treatment of tuberculosis upon the populace in general. National prejudice and customs, to some extent, perhaps, masked in robust health by the voluntary control of the individual, come very obviously to the surface in disease. The German, disciplined from the cradle to the grave, finds it much less hard to submit to the strict régime of the sanatorium than the Englishman, in whose eyes, perhaps, the advantages of individual liberty are some- what over-estimated. In these notes, filled with the business of the congress, no space is available even to enumerate its pleasures ; suffice it to say that the congressists found ample re- creation provided for them by the respective authorities in the evening, and returned refreshed by it to their somewhat depressing subject-matter in the morning. F. W. TUNNICLIFFE. NOTES. THE award of the sixth De Morgan medal was made by the Council of the London Mathematical Society on Thursday last, June 8. The medallist is Prof. W. Burnside, F.R.S., and the ground of his selection was for his researches in mathematics, par- ticularly in the theory of groups of finite order. THE death_is announced of Dr. L. A. Charpentier, Professor and Fellow of the Faculty of Medicine, Paris, and member of the Academy of Medicine. Tue German Imperial School for the study of tropical diseases, the establishment of which is due to the suggestion of Prof. Koch, is to be settled at Hamburg. Mr. W. MarrinDALeE has been elected president of the Pharmacutical Society of Great Britain. Mr. STANDEN, Government Quinologist, Madras, has been deputed to visit Java to study the system of planting cinchona and manufacturing quinine there, and will therefore be absent for some months. It is proposed by the Madras Government to considerably extend the cinchona plantations on the Nilgiris, and a large area has recently been cleared close to the Pykara Falls. Mr. H. J. MACKINDER, reader in geography at the Uni- versity of Oxford, has just left England in charge of an expedition, the object of which is to make a thorough study of Mount Kenia, in British East Africa. As already announced, the autumn meeting of the Iron and Steel Institute will be held at Manchester on August 15-18. The preliminary programme shows that numerous visits to engineer- ing and other industrial establishments have been arranged. Receptions will be given by the Lord Mayor of Manchester and the Mayor of Salford. A detailed programme will be issued when the local arrangements are further advanced. This programme will contain a list of the papers that are expected to be read. Tue Société helvétique des Sciences naturelles will meet at Neuchatel on July 31-August 2. On the first day, discourses will be delivered by the president, Prof. Maurice de Tribolet, Prof. Roux, Dr. C. E. Guillaume, and Dr. L. Wehrli. On the following day, the various sections will meet, and on August 2 there will be discourses by Prof. Schroter, Dr. Morin, and Prof. R. de Girard. A number of excursions have been arranged, and there is every promise of the meeting being a successful one. The secretary is Prof. Dr. Henri Rivier, Neuchatel, Vieux- Chatel rr. 156 NATORE [JUNE 15, 1899 We learn from the Allahabad Prone Afail that some im- portant changes are being made in the Meteorological Depart- ment of the Government of India. These comprise the abolition of a number of observing stations which have not proved worth keeping up, and the substitution for them of others in more favourable localities. Of the latter, most important are stations which are to be established at Cherapunji and one or two other places in Assam; which will enable a more careful watch to be kept over the meteorology of the tea districts, also regarding the periodical rise and fall of the rivers which are so important for the jute trade. Arrangements are also being made, but are not yet concluded, for the establishment of an observatory on Dodabatta Peak, the highest point in the Nilgiris, which is likely to be valuable in connection with the warnings of the monsoon. THE preliminary programme of the eighteenth congress of the Sanitary Institute, to be held in Southampton, from August 29 to September 2, has now been issued. The president of the congress is Mr. W. H. Preece, K.C.B., F.R.S. Mr. Malcolm Morris will deliver the lecture to the congress, and Bailie J. Dick, chairman of the Health Committee, Glasgow, will deliver the popular lecture. Excursions to places of interest in connection with sanitation will be arranged for those attending the congress. A conversazione will be given by the Mayor (Councillor G. A. E. Hussey). The congress will include three general addresses and lectures. Three sections will meet for two days each, and deal with (1) sanitary science and preventive medicine, presided over by Sir Joseph Ewart ; (2) engineering and architecture, presided over by Mr. James Lemon; (3) physics, chemistry and biology, presided over by Prof. Percy F. Frankland, F.R.S. There will also be eight special conferences. A PARLIAMENTARY paper has just been issued showing the number of experiments performed on living animals during 1898, under licences granted under the Act 39 and 40 Vict., c. 77; distinguishing painless from painful experiments. Nearly all the experiments made under the certificate which dispenses with the obligation to kill the animal before recovering from anzesthesia, have been inoculations made (under anzesthetics upon rodents) with the object of diagnosing rabies. During the past three years, the number of experiments other than those of the nature of inoculations, hypodermic injections or similar pro- ceedings has shown little variation (1516, 1462,.1511), while those of that character have increased (5984, 7360, 7640). Many of these latter experiments are performed in the course of pro- fessional duty for the diagnosis of disease, the preparation of antitoxins, the testing of water, and so forth. During the past year 43,000 doses of diphtheria antitoxin have been issued from two institutions. THE second biennial engineering conference, held at the Insti- tution of Civil Engineers last week, was opened by the president, Mr. W.H. Preece, K.C.B., F.R.S. This conference was not an international one in the sense of that held at Chicago in 1893, or of that which is contemplated in the year 1901 in Glasgow, in connection with the exhibition to be held there, but it may well be Imperial ; and in furtherance of this idea the president suggested that, at the next conference, the Council should take measures to secure the presence of some members, delegated specially to represent engineering in parts of the British Empire beyond the seas. In the course of his address, the pre- sident remarked: ‘Science has followed, it has not led engineering. It is their intimate association which is the foundation of all industrial progress. The war of the microbes, the latest development of biology, is a consequence of sanitary requirements. Our knowledge of the diffusion of molecules and NO. 1546, VOL. 60] the solution.of solids has sprung from the investigation into the mechanical properties and constitution of iron and its alloys, and the disturbances of the ather are becoming familiar through the practice of the so-called wireless telegraphy. Facts are derived from accident, observation or practice ; laws are the result of research. Engineers have always appreciated science up to the hilt, but. they wish that its special votaries were less dogmatic and more modest.” Appreciative reference was made to the work of investigators like Newton, Faraday, Lord Kelvin, Lord Armstrong, Lord Lister and Lord Rayleigh ; otherwise the remarks quoted would convey the impression that purely scien- tific investigations, such, for instance, as. were made by Faraday, Clerk Maxwell, and Hertz, had followed instead of preceded advances in applied electricity. THE U.S. Congress has shown appreciation of the valuable work accomplished by the Department of Agriculture by pro- viding increased funds for many of the bureaus and divisions. We learn from the Experiment Station Record that the grant recently made by Act of Congress provides an increase of nearly 200,000 dollars over last year, and of more than half a million dollars over the year previous, the total appropriation for the closing fiscal year of the century being 3,726,022 dollars. This includes 720,000 dollars for the agricultural experiment stations in forty- eight States and territories, and a special grant for,the establish- ment and maintenance of experiment stations in Alaska. The largest increases in appropriation are for the Weather Bureau and the Bureau of Animal Industry. The total grant for the Weather Bureau is 1,022,482 dollars, which includes an increase of 60,000 dollars for the maintenance of the new stations in the West Indies and adjacent coast, and 25,000 dollars for the erec- tion of an addition to the present buildings of the Bureau in Washington. The total appropriation forthe Bureau of Animal Industry is 1,044,030 dollars. This includes 50,000 dollars additional for investigations and inspection, and 20,000 dollars ‘*for the purchase and equipment of land in the vicinity of Washington for an experiment station for the study of the diseases affecting the domesticated animals.” The fund for irrigation in- vestigations has been increased to 35,000 dollars. A grant of 10,000 dollars has been made for tobacco investigations, including the mapping of tobacco soils ; study of soils and conditions of growth in Cuba, Sumatra and other competing countries ; investi- gations of the methods of curing, with particular reference to fermentation ; and originating improved varieties by means of selection and breeding. The Division of Chemistry receives 34,000 dollars—an increase of 5300 dollars—2500 dollars of which is for the equipment of a new laboratory. These addi- tional grants will materially strengthen the Department of Agriculture and extend its sphere of usefulness. THE process of manufacturing mechanical wood pulp is de- scribed by Mr. W. A. Hare in a volume just received, con- taining papers read before the Engineering Society of the School of Practical Science, Toronto. Within the past two or three years there has been a marked impetus given to the pulp and paper industry in Canada. Wood pulp will, for many years to come, be used to supply the world’s demand for a filler in the manufacture of paper, in many of the coarse grades of which it is the only constituent. It is not confined, however, to the manufacture of paper alone, but is made into many useful articles of daily service, the market for which is increasing rapidly. No country in the world is better adapted than Canada for the establishment and expansion of wood pulp manufactures ; and a prosperous future may be anticipated for the industry. THE report of Mr, W. E. Plummer, Director of the Liver- pool Observatory, upon the observations made during 1898, has been issued by the Mersey Docks and Harbour Board. JuNE 15, 1899] NATURE a7, The results of astronomical and meteorological observations are recorded, and mention is made of the latest addition to the equipment of the observatory—namely, a seismograph, which has been placed in the basement, upon the solid rock which forms the foundation of the observatory. The instrument re- corded a disturbance on September 17, 1898, probably having its origin in an earthquake near Tashkent, and it also regis- tered movements produced by an earthquake at Port-au-Prince on December 29. Mr. Plummer hopes that during the year he will be able to trace the effects of tidal motion in the estuaries of the Dee and Mersey upon the seismograph in the observatory. FroM an intemperate article in the /ouwrnal of Indian Engineering we learn of a regrettable state of feeling in Hong KKong concerning the comparative efficiencies of the Kowloon Observatory, of which Dr. Doberck is director, and the Jesuit Observatories of Manila and Zi-ka-wei. The Jesuit Fathers have long sent telegraphic messages connected with weather forecasts and storm warnings to the Spanish Consuls in Hong Kong, Shanghai and Singapore, who have forwarded the intelligence to the various newspaper offices in the respective districts, where they have been published for the benefit of the public at large. It is contended on behalf of the Jesuits that this voluntary service was of the greatest assistance to the mercantile marine and commerce of those ports: that the work was well organised and accurate and deserving of support and encouragement. But it is also alleged that the Secretary of War of the United States has peremptorily forbidden the despatch of these meteorological telegrams to any place outside the Philippines, and that this action has been put into operation onan appeal from Dr. Doberck. The charge uttered against Dr. Doberck is that he has used his influence with the U.S. Weather Bureau to move the Secretary of War (now the governing authority in Manila) to suppress the Jesuits’ correct telegrams in order that his own forecasts may pass unchallenged. But surely the public can test the accuracy and value of weather forecasts, with or without any assistance from the Manila authorities. It is ill-judged policy to limit the distribution of any scientific information ; and as in the present case the work is done voluntarily by the Jesuit Fathers, it is difficult to under- stand why the issue of the weather despatches has been forbidden. DurinG the last week of May, Mr. Walter Garstang, of the Marine Biological Association, carried out the second of his periodical surveys of the biological and physical conditions of the western region of the English Channel. The steam-tug Stormcock was again employed, and the same stations were visited as in February, viz., mid-Channel (50 fathoms), Ushant (60 fathoms), Parsons Bank, 50 miles W.N.W. from Ushant (75 fathoms), and Mounts Bay (45 fathoms). The distribution of temperature presented several noteworthy features. At the Ushant station, in spite of the depth of water, the temperature was found to be uniformly high from top to bottom; but at all other stations a surface layer of warm water overlay a deeper mass of cooler water. This warm surface layer was 7 fathoms deep in Mounts Bay, 10 to 15 fathoms deep in mid-Channel, and 15 to 20 fathoms deep over Parsons Bank. The temper- ature at 5 fathoms depth was 5370 F. in mid-Channel, 53°:2 in Mounts Bay, 54°1 off Ushant, and 54°°5 at Parsons Bank. Rich collections of plankton were made at all stations in a variety of ways. The apparatus employed consisted of a surface tow-net, a fine vertical net after Hensen’s pattern and a pump and 40 fathoms of hose for quantitative work, and a new form of opening and closing net for towing horizontally at any required depth. By means of this net many interesting features in the vertical distribution of plankton at the different stations were brought to light. Among the more interesting forms captured during the cruise may be mentioned the medusa NO. 1546, VOL. 60] Fybocodon prolifer (mid-Channel, and Mounts Bay, 40 fathoms), the siphonophore 4ga/mopsis (Parsons Bank, upper strata), the copepod Jséas clavzpes (Ushant, 3 fathoms), 7orzarza, the larva of Balanoglossus (Parsons Bank, surface), and the eggs and larvae of the pilchard (Ushant, 69 fathoms, and at the surface at all stations except Mounts Bay). THE director of the National Observatory of Athens has pub- lished (1898) a first large quarto volume of its 4za/s, containing (1) an elaborate discussion of the meteorological observations made from 1839 to 1893, and (2) the detailed observations for the years 1894 and 1895; for the latter year, observations are given for every hour, and means are calculated for daily, ten- daily, monthly and yearly periods. The present observatory was regularly established in 1840, at the expense of Baron Sinas, and he also supplied it with the necessary instruments. The first director was Prof. G. Bouris, and the present director is Prof D. Eginitis. As now constituted, the observatory is divided into three sections: astronomy, meteorology and geodynamics, with a separate chief for each service, under the general superintendence of the director. From this long series of observations we note that the maximum temperature recorded was 105°°3, and the mean of the maxima 100°'2 ; the minimum was 19°°6, and the mean of the minima 291. The average yearly rainfall (1858-94) was 16 inches; the driest month is July, and the wettest months November and December. The number of rainy days averages 99 in the year. In addition to the statements referring to observations made with instruments during the present century. the author gives, under each section, some interesting quotations relating to the ideas and observ- ations of ancient Greek and Latin writers. Many characteristics of the climate of Greece are contained in almanacs dating from the fifth century B.c., and they are frequently found to confirm the results deduced from modern observations. WE have received from Prof. H. Mohn, Director of the Norwegian Meteorological Service, a pamphlet on the employment of the boiling point thermometer in determining the pressure cf the air and the correction for gravity. As recommended by recent meteorological conferences, the correction for gravity is now generally applied or quoted in meteorological tables. But the correction calculated accord- ing to formule differs more or less from that determined by actual pendulum experiments, and there are comparatively few meteorological stations where such experiments have been made. It is therefore important for meteorologists to find another means of determining this correction, and in the work in ques- tion Prof. Mohn publishes the results of experiments made at a number of land stations; and he shows that the correction for gravity may be very accurately determined by the improved thermometers used in conjunction with a mercurial barometer, the difference of the reduced readings being the correction ree quired. It will be interesting to find whether the methods proposed could be employed at sea; at all events, a compar- atively smooth sea would be necessary for the experiments. AN ‘‘ Annual Review of Physics,” by M. Lucien Poincaré, is a valuable feature of the Revue générale des Sctences for May 30. It contains a summary of the chief discoveries made by physicists during the past year, classified under their various headings. Speaking of progress generally, it is pointed out that our knowledge of physics has not been revolutionised by any epoch-making discoveries like those of Rontgen and Zeeman, but that the year has been spent chiefly in extending and completing the knowledge of known phenomena. THE latest researches on the propagation of malaria, by Prof. Grassi, in conjunction with Bignami and Bastianelli, show that all the species of the genus Avopheles hitherto observed by 158 NATURE [JuNE 15, 1899 the writers are capable of transmitting this disease. Experiments bearing on the hereditary transmission of the disease among the mosquitos themselves have hitherto led to negative results. Specimens of Azopheles claviger have been bred from parents taken in malarial houses, but no sporozooids have been observed in their salivary glands. Moreover, several observers have allowed themselves to be freely bitten by newly-bred mosquitos taken from malarial districts, but in no case have any ill effects been experienced. The present evidence tends to show that those 4nopheles which have not bitten malarial patients are not infected, and are incapable of inoculating the disease ; a single positive result would, however, disprove this conclusion. Mk. STEWART CULIN still continues his interesting com- parative studies of games ; and in the Bzd/etin No. 3 of the Free Museum. of Science and Art, Philadelphia, 1898, he dis- cusses the ‘‘platter” or dice of the American Indians, and finds that they originated from arrows and a throwing-stick used for divinatory purposes. He is of opinion that all the various forms of the game are not only derived, one from another, but that its place of origin may be definitely fixed in the country of the reed arrow and the a¢/ad/, or throwing-stick ; that is, in the arid region of the South-Western United States and Northern or Central Mexico. Various items of Indian folk-lore will be found in the Journal of the Asiatic Society of Bengal, vol. \xvii. Carat Candra Mitra writes on Bengali and Behari bird folk-lore and omen birds. The same author has a paper on coincidences be- tween some Bengali nursery stories and South Indian folk-tales, in which he discusses the migration of folk-tales, and concludes as follows: ‘‘ The similarity between the Bengali and South Indian versions of these tales can be accounted for only on the supposition that the aboriginal Bengali and Dravidian races assimilated the tales from Aryan settlers, the slight variations between the said two versions being due to the difference be- tween the two borrowing races as regards manners, customs and language.” Astronomical folk-lore is narrated by Ramgharib Chaube. THE fourteenth fasciculus of the ‘‘ North American Fauna,” under the editorship of Dr. Merriam, is devoted to the biology of the Tres Marias Islands, the larger portion of the text being by Mr. E. W. Nelson. These islands, which lie off the west coast of Mexico, about sixty-five miles from the port of San Blas, have only recently been systematically explored by collectors. As might have been expected, this exploration clearly demonstrates their continental origin, their situation showing that at one period after their separation they formed a single larger island. The birds and mammals seem to have been more susceptible to modifying influences than has been the case With other groups, seven out of ten representatives of the Tatter, and twelve out of thirty-six of the former, being regarded as entitled to specific or sub-specific distinction. Mr. NELSON has likewise been devoting attention to the squirrels of the mainland of Mexico and Central America, the results of his investigations appearing in the May issue of the Proc. Washington Academy. It is concluded that the arboreal squirrels of North America should be divided, from the char- acters of the skull, aided sometimes by external peculiarities, into ten distinct sub-generic groups, four of which receive new names, The sub-genera are stated to occupy clearly defined geographical areas—a fact which speaks clearly as to their intrinsic import- ance ; and it is further noticeable that the ranges of the most closely allied groups are invariably separated from one another by distinct gaps. Considerable importance as a group-character is attached to the presence or absence of the anterior upper pre- molar, and its relative size when developed. NO. 1546, VOL. 60] IN his paper on ‘‘ Mid-winter Surface and Deep Tow-nettings in the Irish Sea,” recently published in the Zvans. Liverpool Biol. Soc., Mr. I. C. Thompson urges the importance of correlating the gatherings taken from upper and lower strata at the same time, much remaining to be learnt as to the effects of temperature and other influences upon the minute forms of marine life. In the Bol. Mus. Paraense for December last, the energetic director of the museum, Dr. E. Goeldi; laments the un- satisfactory state of our knowledge of the Brazilian fish- fauna, mentioning at the same time that although it is a subject to which his attention has long been directed, means and opportunity have been lacking. A commencement is, however, now made in the present synopsis of the fishes of Amazonia and the Guianas, which includes nearly forty pages of text, and a double coloured plate. The excellent execution of two of the figures in the latter, representing species recently described by Mr. Boulenger, is a very satisfactory feature. THE April number of the Agricultural Gazette of New South Wales contains an illustrated account of a small ostrich-farm at South Head, where nine birds are kept. The methods of plucking and making-up the feathers are described and photo- graphed. The annual product of each bird is werth from 10/7. to 152. ; and the owner is of opinion that the industry is likely to prove a thriving one in the Colony. He considers that the birds, instead of being allowed to roam over large areas, as at the Cape, should be kept in small paddocks, and shifted from one to another of these at short intervals. A PAPER by Mr. F. A. Lucas on the fossil bison of North America, published in the Proc. U.S. M/us., vol. xxi., pp- 755-777, is specially noticeable for its wealth of illustration, having over twenty plates, The author, in opposition to some previous writers, is of opinion that all the bison skulls hitherto found in America are specifically distinct from the os priscus of Europe. No less than six extinct species are recognised ; and while one of these is certainly a very distinct form, yet if all the others are valid species, it may be taken as certain that the fossil bison skulls of Europe would also permit of considerable specific division. One of the most important items in the paper is the determination that the so-called Bos scaphoceras of Cope, from Nicaragua, is not a bison at all, but a sheep. It seemed very strange that a representative of the former animals should have wandered so .ar south during the Pleistocene. PERHAPS the most generally interesting article in the May number of the American Naturalist is one by Mr. Herrick, describing a case of the occurrence of a small hen’s egg within one of ordinary size. Not that such abnormalities are uncommon —far from it. But the interest of the present case lies in the fact that the enclosed egg was situated in the yolk, instead of in the albumen of the larger specimen. In this respect it appears to be unigue. The different types of such abnormalities are con- sidered in detail. In ordinary cases, it seems that the small included egg represents a fragment of a normal ovum which has been ruptured, and has thus parted with some of its substance after leaving the ovary. Usually this fragment is treated in the oviduct like a full-sized egg and duly laid ; but it may rarely be driven by antiperistaltic action up the tube so as to collide with the mother-egg, with which it fuses. From the general absence of yolks in such included small eggs, the ruptures that take place in the upper part of the oviduct must, as a rule, be con- fined to the albumen. Other explanations are given to account for double- or treble-yolked eggs. Ir is curious to note how the natural history of the fast- waning group of giant land tortoises is being gradually pieced June 15, 1899] NATURE 159 together from the evidences of living specimens transported far from their original habitat. An instance of this is afforded by Mr. E. R. Waite’s description in the last issue of the Records of the Australian Museum of a male and female of Zestudo nigrita recently living in the grounds of the Gladesville Hospital, near Sydney. The female, which died in 1896, was brought from the Galapagos in 1853, and the male, which has been acquired by Mr. Walter Rothschild, about 1866. Un- fortunately, in neither case is there any evidence as to the particular island in the Galapagos group from which they were obtained, so that the exact habitat of the species still remains unknown. SPECIAL interest is naturally felt at the present time in the geology of many of the islands in the Malay Archipelago, and therefore the summary just published by Dr. B. Koté, Professor of Geology at Tokyo, will be of service (Yowrn. College of Science, Imp. Univ. of Tokyo, Japan, vol. xi. part 2). The author acknowledges his indebtedness to the labours of Prof. Suess ; but he gives additional information, his object being to compare the structure and physical features of Taiwan with those of the Far Eastern Indies. Brief references are made toa great variety of strata and to the volcanic phenomena. WE have received the summary report of the Geological Survey of Canada for 1898, in which the Director, Dr. G. M. Dawson, records the progress of the Survey, and quotes from the reports of the several officers on the staff ‘‘the more im- portant results of their investigations, particularly such as may be of immediate value to the public from an economic stand- point.” In northern Alberta some further experimental borings have been made in search of petroleum, and great trouble has been experienced in the effort to penetrate the “‘tar-sands”’ at the base of the Cretaceous strata, owing to ‘‘ the clotting of the casing and tools with the heavy tarry petroleum, or maltha, mixed with sand, which was thrown up by the discharge of gas,” The indications of oil-bearing strata have been proved over a large area, and it is hoped that the liquid petroleum may be found in the Devonian limestones which underlie the Cretaceous rocks, Mr. R. G. McConneLr and Mr. J. B. Tyrrell’s report on the Klondike Region, Yukon District, is referred to in the pub- lication mentioned in the foregoing note. The productive part of the Klondike gold-field, as at present known, covers an area of one thousand square miles. The gold occurs in the gravels flooring the bottom of the valleys, in stream-terraces lining the lower slopes of the valleys, and in a remarkable moraine or glacial deposit that occurs along the slopes of Eldorado and Bonanza creeks. The gold has been derived from the rocks of the immediate vicinity, and these consist of schists probably of Cambrian age. In various regions the want of good topo- graphical surveys is a sad hindrance to the geological work, but that this is carried on in various portions of the vast territory of Canada with great energy and enthusiasm is evident from the details enumerated in this report of the Canadian Geological Survey. There are numerous observations on petrology, palzzontology, and natural history generally. A large number of ceptilian remains have been obtained from the Belly River form- ation in the Red Deer River district. The age of the formation, judged by the invertebrate fauna, is considered by Mr. Whiteaves to be the same as that of the Laramie (Cretaceous) series. In Nature for January 19 we gave a brief account of the progress of the Maryland Geological Survey, which is under the direction of Prof. W. B. Clark, State Geologist. We have since received the second volume issued by the Survey, which embodies the full reports to which we previously alluded. As in the case of the first volume, it is beautifully printed and NO. 1546, VOL. 60] handsomely illustrated. The coloured plates picturing the macroscopic appearance of various granites and the Potomac marble are particularly good. There are, moreover, numerous pictorial views of quarries and of the physical features ; there are excellent topographic and geological maps, and repro- ductions of some of the earlier topographic maps dating from 1527. The volume is mainly occupied (1) with an account of the building and decorative stones of Maryland, by Mr. G. P. Merrill and Mr. E. B. Mathews, by whom the physical, chemical, and economic properties of the stones, and their distribution, are: very fully considered ; and (2) by a report on the cartography of Maryland by Mr. H. Gannett and Mr. E. B. Mathews, who deal with the aims and objects of cartography, and with the maps and map-makers of Maryland. Mr. G. K. GILpert describes a ‘‘ Bowlder-Pavement” (to use the American spelling) at Wilson village, about twelve miles east of Niagara river, New York (Journal of Geology, Nov.-Dec. 1898). Such a pavement is formed when the boulders in till or boulder-clay are grouped in an approximately horizontal plane, and are striated on their upper surfaces in a common direction. The features are indicative of local glacial action which has affected a previously accumulated till, this action having removed a certain amount of material and caused the pressing down and striation of boulders along the plane of erosion. IN treating of the glacial sculpture in Western New York (Bull. Geol. Soc. America, March), Mr. Gilbert shows how the broad plateau of Niagara limestone was but little modified, while its escarpment was rendered more prominent owing to the excavation by ice of the underlying shales which occupy the lowlands. Mr. Gilbert draws attention to a flexure produced by ice-action in the Medina shales at Thirty-mile Point, New York; and in a subsequent article he describes some giant ripple-marks in the Medina sandstones of New York, and these suggest that the formation was laid down in a large ocean whose waters were agitated by storm waves sixty feet high. Mr. G. CLARKE NUTTALL contributes to the current number of Zhe Contemporary Review a popular account of the dependence of the flavour of tobacco upon the activity of bacteria during that important stage in the preparation of tobacco known as fermentation, Interesting reference is made to the work of Suchsland, who examined the germs which he found in the fermenting heaps of the finest West Indian tobacco. This German bacteriologist isolated and cultivated these bacteria, and then introduced some into quantities of inferior German tobacco, which was subsequently transformed so that connoisseurs could not distinguish it from the finest brands of tobacco. WE have received from Messrs. Dulau and Co. a copious list of books and papers in British botany offered for sale. CoursEs of instruction in cryptogamic and cytological botany are given at the Marine Biological Laboratory, Woods Hole, Mass., during July and the early part of August. HERR J. DORFLER, the compiler of the Botandsts’ Directory, proposes to publish a new edition about the commencement of the year 1900, and desires the co-operation of the botanists of all countries. His address is Barichgasse 36, Vienna IV. A CIRCULAR has been issued inviting the attention of bio- logists to the biological station at Ambleteuse, in the Depart- ment of Pas-de-Calais, France. It has been erected very much on the plan of the American station at Wood’s Hole, and is primarily designed as a summer school for biological students in connection with the Catholic University of Lille. THE Reading College Agricultural Department has just issued its Fifth Annual Report on Field Experiments for 1898. The experiments were carried on with the co-operation of the Coun 160 NALORE [June 15. 1899 Councils of Berkshire, Oxfordshire, Dorsetshire, and Hamp- shire, subsidies being granted by these bodies to the College to meet the expenses. The experiments were chiefly concerned with manuring and the rotation of crops, and furnished results which ought to be useful to farmers. Only one disease of cultivated crops, the “ finger-and-toe,” appears to have been attacked. Experiments on the cultivation of the sugar-beet in the neighbourhood of Reading gave good results. We notice that the staff of the College engaged on the field experimental work comprised two lecturers in agriculture, a lecturer in chemistry, an assistant chemist, a lecturer in geology and meteorology, and the director of the agricultural department, but no botanist or entomologist. MAny admirers of Tyndall’s writings will be pleased to know that the volume entitled ‘‘ Hours of Exercise in the Alps,” which has been out of print for some years—the last edition (the third) having appeared so far back as 1873—-has been re- printed. Many adventures in the Alps and elsewhere are narrated therein, and the volume has as much freshness and vigour now as ever it had. Messrs. Longmans, Green, and Co. are the publishers. A NEW volume of the ‘‘ Year-Book of the Scientific and Learned Societies of Great Britain and Ireland” has just been published by Messrs. Charles Griffin and Co. The volume con- tains, not only particulars as to officers, meetings, and member- ship of learned societies, but also lists of papers read before, or published by, every Society of importance throughout the kingdom during 1898. Asa convenient work of reference, the volume only needs to be known to be used. THE current number of the Phofogram contains as a supple- ment a very excellent reproduction of a snow scene, entitled “* A Winter’s Night,” on special rough velox paper. The same number also contains the spectrum of iron and the solar com- parison (on a slightly reduced scale), which has recently been obtained direct 9n a film thirty inches long at one exposure at the Solar Physics Observatory, South Kensington. As Rugby was the first of the Public Schools to afford facilities for the study of science, we look to the Natural History Society of the School for a good report ; and the one just issued is not disappointing. A prize essay, by Mr. P. H. Bahr, on ‘‘ The Birds of Staffordshire and North Wales,” is included in the report, together with reports on the work of various sections, and Mr. G. M. Seabroke’s report on the observations made at the Temple Observatory in 1898. THE course of study in technical electricity, arranged by M. Eric Gerard for the Montefiore Electro-technical Institute of the University of Liége, formed the basis of a volume of ‘*Lecons sur l’Electricité ” written by M. Gerard, and published several years ago by MM. Gauthier Villars et Fils. The first volume of the sixth edition of this work has just been received. The subjects dealt with are the theory of electricity and mag- netism, electro-magnetic induction, electrical measurements, thermo-electricity, dynamo-electric machines, transformers and alternating currents. Many changes have necessarily been made in order to include some of the more important inyentions and discoveries of the past few years. The volume now runs into 819 pp., and is illustrated with 388 figures. MAny practical hints for photographers are given by Dr. E. Vogel in his ‘t Taschenbuch der praktischen Photographie,” the sixth revised and enlarged edition of which has just been pub- lished by the frm of Gustav Schmidt, Berlin. Among the additions to the volume is a description of the preparation of, and printing with, potassium bichromate paper (Gummidruck). Concise notes on the materials and methods available for the production of good negatives and various kinds of prints form a NO. 1546, VOL. 60] characteristic of this photographer's pocket-book. —Another pho- tographic publication just published by the firm of Gustav Schmidt is a new part of the fourth edition of the late Dr. H. W. Vogel’s ‘‘Handbuch der Photographie,” edited by P. Hanneke. The subject of the new section is photographic printing by different kinds of processes. “*PicruRE Taking and Picturing Making” is the title of a neat and clearly printed little book of 115 pages, published by the Eastman Kodak Company. The object of this guide, as we may call it, is not to deluge the reader with theories and technicalities of photographic optics and formule, but to state clearly the main features regarding the production of good negatives, prints, and lantern slides. Parts of the book are somewhat familiar, in that they have appeared in the small Kodak manual ; but the reader will find much that is new and useful. Needless to say, there are numerous and well-reproduced illustrations. In the ‘‘ Year-Book of Photography and Amateurs’ Guide” the reader will find that the 650 pages of which it is composed contain a mine of information that should be of the greatest service to the photographer, whether he be amateur or pro- fessional. The five sections of the book, which bring before us progress and practice, being a collection of helpful articles by practical photographers, the tourists’ companion and holiday guide from the photographic point of view, winter work, facts and formulz, and, lastly, novelties of the year, contain useful and valuable information suitable for every one. Not less im- portant is the collection of fine reproductions from negatives, on many different subjects, taken with several kinds of cameras and shutters, which lends an additional charm to this year’s volume. The author has succeeded in presenting his readers with, not only an interesting volume to read, but one that should be at the side of every amateur for reference. A SECOND edition of ‘‘ The Aborigines of Tasmania,” by Mr. H. Ling Roth, has been published by Messrs. F. King and Sons, Halifax. Ina supplementary note to the preface, Prof. E. B. Tylor points out that since the publication of the first edition, nine years ago, noteworthy progress has been made in the an- thropological study of,the Tasmanians. He adds, ‘‘ That these rude savages remained within the present century representatives of the immensely ancient Paleolithic period, has become an admitted fact. . . . That the workmanship of the Tasmanians may be generally taken as below that of the Palzolithic Drift and Cave men, is apparent from the absence of any Tasmanian implement comparable to the symmetrical pointed picks worked on both sides, characteristic of the Mammoth Period in Europe.” The additional information and figures referring to the position of the Tasmanians in the history of the human race make Mr. Ling Roth’s volume of exceptional interest to students of anthropology. THE additions to the Zoological Society’s Gardens during the past week include a Sooty Mangabey (Cercocebus fuliginosus, 2 ) from West Africa, presented by Mr. G. Le Tantt; a Bonnet Monkey (Macacus sinicus,9) from India, presented by Mrs. C. Tarrant ; two Slender Loris (Zors graczls) from Ceylon, presented by Mr. Stanley S. Flower; a Leopard (fe/zs pardus, ) from Ceylon, presented by Mr. Edward Booth; a Black-backed Jackal (Canis mesomedas) from South Africa, pre- sented by Mr. David D. Keith; a Two-spotted Paradoxure (Nandinia binotata) from West Africa, presented by Mr. Arthur Knights; a Vervet Monkey (Cercopithecus Jalandit) from South Africa, presented by Mr. G. Marson; a Brown Gannet (Su/a deucogastra) from Accra, presented by Miss Williams; a White-backed Piping Crow (Gymnorhina leuconota) from Australia, presented by Mr. G. T. Harris ; two Common Vipers ( Vipera bervus) from Hampshire, presented by Mr. Chas. JuNE 15, 1899] NAT ORE 16! C. Dallas ; an Algerian Skink (Zzweces algeriensis) from North Africa, presented by Mr. R. H. Archer; a Rufescent Snake (Leptodiva hotambaeia), a Hissing Sand Snake (Psanmophes sibilans) from South Africa, presented by Mr. W. Champion ; three Barbary Turtle Doves ( Zvrtur rzsorzus) from Africa, pre- sented by Colonel E. J. Gardiner ; three Blue-necked Casso- waries (Casuarius intensus) from New Guinea, a Senegal Parrot (Pacocephalus senegalensis) from West Africa, two Mute Swans (Cygnus olor, 28), European; an Echidna (Zchidna hystrix) from New South Wales, deposited; a Hunting Crow (Céssa venatoria) from India, three Bar-tailed Godwits (Zzmosa lap- ponica). four Black-tailed Godwits (Zzmosa aegocephala), ten Green Lizards (Lacerla viridis), four Toads (Bombznator bombinus), European, purchased; a Japanese Deer (Cervzs stka, 8), an English Wild Cow (os taurus), two Squirrel-like Phalangers (Petaurus sctureus, 29), two. Short-headed Pha- langers (Petaurus breviceps, 2 6), a Patagonian Cavy (Dolichotus patachonica), a Crested Porcupine (Aystréx cristata), a Hybrid Lemur (between Lemur macaco and Lemur brunneus), born in the Gardens. OUR ASTRONOMICAL COLUMN. TEMPEL’s COMET (1873 II.)—Continued from SW QG ee XU ers ENAT UND XIILGNE XIV sS0UNXVII EEX VI SUNTNID VII NEXUIIE Fic. 1.—Grade curves for height of public schoolboys from 103 to 18} years ofage. The figures on the base line refer to age. The figures down the centre of the diagram are the numbers of the grades, which are bounded by the two curves between which the several numbers are placed. There is no lower limit to grade 20, nor upper limit to grade 1. trustworthy in form between the ages of 12 and 18. Beyond these limits the form of the curves may be slightly at fault, owing both to insufficient number of observations and to the process of natural selection which influences the physical status of the majority of boys who come early and stay late at a public school. The curves in Fig. 1 are constructed by marking off on the vertical line through each age the various heights at which the curve of distribution for that age crosses the 5 per cent., 10 per cent., 15 per cent., . . . 95 per cent. lines. Each series of corresponding points is then joined up-by a flowing curve, with the result shown. The central line, between-the numbers 10 and 11, shows where the various curves of distribu- NO. 1548, VOL. 60] tion cross the 50 per cent. line, and consequently indicates the: scheme of growth of the mean boy. It was contended in the paper that since each of these curves. represents the growth of a boy, who develops in such a manner as to preserve always the same relative position amongst his. fellows, they give an accurate idea of the growth which may be reasonably expected from a boy at any stage of his develop- ment, whatever his physical status may be. A glance at the: diagram will show that the rate of growth, which is measured by the pitch of the curves, varies considerably for boys of the same age but of different physique. The period of maximum growth is reached much sooner by a boy of a high grade tham by one of a low grade, and lasts much longer. Thus the steepest pitch of the topmost curve occurs between the ages of 134 and 144, and is sensibly uniform during that period, the correspond- ing steepest pitch in the mean line lies between the ages of 15, and 154, in the lowest line it lies between 164 and 17. Con- sequently, during the period of fastest growth, all boys may be expected to grow at nearly the same rate ; but this rate of growth is reached by some boys three or four years later than by others.. AV. ASS \\ \ NX \ LI \ 60 XI XI Xm = Xlv XVaL Fic, 2.—Similar grade curves for weight. Fig. 2 represents the corresponding series of curves for weight, and teaches much the same lessons; it is evident, however, that the rate of growth in height declines much more rapidly after the period of maximum growth is passed than the rate of growth in weight, consequently boys of the same height but of different ages may be expected to differ consider- ably in weight. That this is generally the case was clearly shown by another set of curves exhibited at the lecture. The curves shown have been used for constructing tables of grades, by means of which the limits of twenty grades are fixed, in some one of which a boy can be immediately placed if his measurements are known. From the mode of construction it is evident that, @ fréovz, each of these grades is equally probable. The tables have in actual practice been found to be of great use in estimating the progress of individuals, and of gymnastic J UNE 29, 1899] classes, &c. Thus an analysis of the grades o. chest-girth of 255 boys before and after a three terms’ course of compulsory gymnastics showed that the following improvement had been made. The numbers in the lower line give the percentage of the boys examined, who made the number of grades improve- ment indicated in the line above. r Improvement :— ‘ rgr.|2er.|3 er. | 4gr-|5er-|6gr.|7gr-| Sgr. | o gr. | rogr. | tr gr. Per cent. :— ode | 2. [mle th ORS |! 4 eo] CRA ieee This with the omitted fractions gave 73 per cent. of the boys who had made more or less marked improvement relative to the general mass of boys of their age, the improvement in some cases being very marked indeed. An analysis of the growth of 161 boys by means of their grades showed that the scheme of growth corresponded to the scheme indicated by the curves in the diagram in 31 per cent. ofthe casesexamined. There was a steady rise relative to this standard in 17 per cent. ; a steady fall in ro per cent. ; a period of rise followed by one of fall, or vice versd, in 18 per cent. In 9 per cent. the variation was erratic, and the remaining 15 per cent. probably belonged to the first group; but not within the limits of variation allowed. In 68 per cent. the type of structure, as indicated by the re- lation of height to weight, was stable throughout the period examined ; but in about one-fourth of these cases there was a considerable constant difference between the grades of height and weight, amounting in the most extreme cases to as much as eight grades. The lesson drawn from these observations was that, in order to form a correct opinion relative to a boy’s physical progress by means of his measurements, it is very desirable to keep a regular record of his growth, in order that the general scheme of his growth may be determined, and that any irregular fluctuations due to external and removable causes may be noted and properly dealt with. The Giant Tortoises of the Galapagos. I NOTICED in your issue of June 15 a paragraph about the Galapagos tortoises. I do not know if this information is of any interest, but during my residence in Hawaii I knew of two living there. One of them lived ina garden near Hilo, and belonged to the late Captain Thomas Spencer ; I last saw it about 1880. The other one lived on the Waimea plains in a perfectly wild state, and I used frequently to come across it when out shooting. It used to wander about within a radius of three or four miles. It was blind of one eye, and its shell had lichen growing on it, and it could move about with a man sitting on its back. I last saw it in 1890, but it may possibly be still living ; this, however, could easily be ascertained. They were, I believe, brought to Hawaii from the Galapagos in whalers, and were of great age. If desired, I shall endeavour to find out if they are still alive. W. HERBERT PURVIS. 10 Alexandra Place, St. Andrews, Fife. School Laboratory Plans. COLLEGE plans are not always safe precedents. Boys need more supervision. Can any of your readers advise as to the best arrangement of benches for a class of twenty-four to thirty boys, aged fourteen to seventeen, doing chemistry and physics with elementary quantitative experiments ? (1) Is the double back-to-back bench the best form? It may economise woodwork, but it makes the class face both ways, and attention to verbal instruction is less easy. (2) Is the superstructure of shelving necessary? If qualita- tive analysis is not done, fewer bottles are needed. The super- structure hinders conversation across double benches, but it stops supervision also. (3) What is the best way of arranging the benches so as to allow of supervision and keep wall spaces free for shelving ? They may be (a) all round the wall, leaving no space for shelves and cupboards ; or (4) single bench along two walls and double bench down the middle ; or (c) across the room, double benches alternating with windows, well lighted but difficult to supervise ; (d) central aisle with double bench extending to walls right and left ; (ec) double benches, Jengthways, free from walls ; (/) single benches, cross-ways, like the desks of an ordinary class-room. I shall be grateful for any help or advice. Bootham School, York, June 23. HucuH RICHARDSON, NO. 1548, VOL. 60] NATURE 199 Pair of Brazilian Marmosets Breeding in England. A PAIR of marmosets, which for the two past winters have had a free run of our greenhouse and garden (in Buckingham- shire), produced two young ones on May 24. They seem to thrive on freedom and exercise, and the young ones are now be- ginning to feed themselves. In hot weather they like to remain out all night, but at first they came in to their box in the green- house every evening, the male parent always carrying the twins on his back, their little round furry heads merely looking like small excrescences each side of his neck; and only handing them to the mother at feeding-times, and then carefully lifting them back with both hands and settling them into position, where they seem to cling on without being held. Their favourite garden house appears to be an old bird’s nest, rather high up ina pink thorn-tree, some distance from the green- house. They very rarely come down to the ground, but the female will answer a call and come to feed from the hand. Bananas, milk and water, insects and young birds are the foods they like best. Dora WHITMORE. THE DIFFRACTION PROCESS OF COLOUR- PHOTOGRAPHY. Ape production of colour by photography has been accomplished in two radically different ways up to the present time. In one, the so-called Lippmann process, the waves of light form directly in the photographic film laminze of varying thickness, depending on the wave- length or colour of the light. These thin laminz show interference colours in reflected light in the same way that the soap-bubble does, and these colours approximate closely to the tints of the original. The technical difficulties involved in this process are so great that really very few satisfactory pictures have ever been made by it. The other, or three-colour process, has been developed along several distinct lines, the most satisfactory results having been produced by Ives with his stereoscopic “ Kromskop,” in which the reproduction is so perfect that, in the case of still-life subjects, it would be almost impossible to distinguish between the picture and the original seen through a slightly concave lens. The theory of the three-colour method is so well known that it will be unnecessary to devote any space to it, except to remind the reader of the two chief ways in which the synthesis of the finished picture is effected from the three negatives. We have first the triple lantern and the Kromscope in which the synthesis is optical, there being a direct addition of light to light in the com- pound colours, yellow being produced, for example, by the addition of red and green. The second method is illustrated by the modern trichromic printing in pigments. Here we do not have an addition of light to light, and consequently cannot produce yellow from red and green, having to produce the green by a mixture of yellow and blue. Still a third method, that of Joly, accomplishes an optical synthesis on the retina of the eye, the picture being a linear mosaic in red, green and blue, the in- dividual lines being too fine to be distinguished as such. The diffraction process, which I have briefly described in the April number of the Philosophical Magazine, is really a variation of the three-colour process, though it possesses some advantages which the other methods do not have, such as the complete elimination of coloured screens and pigments from the finished picture, and the possibility of printing one picture from another. The idea of using a diffraction grating occurred to me while endeavouring to think of some way of impressing a surface with a structure capable of sending light of a certain colour to the eye, and then superposing on this a second structure capable of sending light of another colour, without in any way interfering with the light furnished by the first structure. This cannot, of course, be done with inks, since if we print green ink over red, the result will not be a mixture of red light and green 200 NATURE [JUNE 29, 1899 light, but almost perfect absence of any light whatever ; in other words, instead of getting yellow we get black. Let us consider first how a picture in colour might be produced by diffraction. Place a diffraction grating (which is merely a glass plate with fine lines ruled on its surface) before a lens, and allow the light of a lamp to fall upon it. There will be formed on a sheet of paper placed in the focal plane of the lens, an image of the lamp flame, and spectra, or rainbow-coloured bands on each side of it. Now make a small hole in the sheet of Lamp Flame Vv Sa dupes paper in the red part of one of these spectra. This hole is receiving red light from the whole surface of the grating, consequently if we get behind the paper and look through the hole we shall see the grating illuminated in pure red light over its whole extent. This is indicated in Fig. 1, where we have the red end of the spectrum falling on the hole, the paths of the red rays from the grating to the eye being indicated by dotted lines. Now the position of the spectra with reference to the central image of the flame depends on the number of lines to the inch with which the grating is ruled. The finer the ruling the further removed from the central image are the coloured bands. Suppose now we remove the grating in Fig. 1, and substitute for it one with closer ruling. The spectrum will be a little lower down in the diagram, and instead of the red falling on the hole, there will be green ; consequently, if we now look through the hole, we shall see this grating illuminated in green light. A still finer ruling will give us a grating which will appear blue. Now suppose that the two first gratings be put in front of the lens together, overlapping as shown in Fig. 2. This combination will form two over- lapping spectra, the red of the one falling in the same place as the green of the other, namely on the eye-hole. The upper strip, where we have the close ruling, sends Fic. 2. green light to the eye and appears green ; the under strip, with the coarser ruling, sends red light to the eye and appears red, while the middle portion, where we have both rulings, sends both red and green light to the eye, and in consequence appears yellow, since the simul- taneous action of red and green light on any portion of the retina causes the sensation of yellow. In other words, we have in superposed diffraction gratings a NO. 1548, VOL. 60] structure capable of sending several colours at once to the eye. If we add the third grating, we shall see the portion where all three overlap illuminated in white, produced by the mixture of red, green and blue light. Three gratings with 2000 lines, 2400 lines, and 2750 lines to the inch, will send red, green and blue light in the same direction, or, in other words, to the same spot on the screen behind the lens. Suppose, now, we have a glass plate with a design of a tulip, with its blossom ruled with 2000 lines to the inch, its leaves ruled with 2400, and the pot in which it is growing ruled with 2750 lines, and place this plate before the lens. On looking through the hole we shall see a red tulip with green leaves growing in a blue pot. Thus we see how it is possible to produce a coloured picture by means of diffraction lines, which are in themselves colourless. Those portions of the plate where there are no lines send no light to the eye, and appear black. We have now to consider how this principle can be ap- plied tophotography. That photographs whichshow colour on this principle can be made, depends on the fact that a diffraction grating can be copied by contact printing in sun-light, on glass coated with a thin film of bichromated Fic. 3. gelatine. The general method which I have found best is as follows. Three gratings ruled on glass with the requisite spacing were first prepared.? To produce a picture in colour three negatives were taken through red, green, and blue colour filters in the usual manner. From these three ordinary lantern-slide positives were made. A sheet of thin plate-glass was coated with chrom gelatine, dried, and cut up into pieces of suitable size ; one of these was placed with the sensi- tive film in contact with the ruled surface of the 2000-line grating, and the whole covered with the positive repre- senting the action of the red light in the picture. An exposure of thirty seconds to sunlight impressed the lines of the grating on the film in those places which lay under the transparent parts of the positive. The second grating and the positive representing the green were now substituted for the others, and a second exposure was made. The yellows in the picture being transparent in both positives, both sets of lines were printed superposed in these parts of the picture, while the green parts re- ceived the impression of 2400 lines to the inch only. The same was done for the blue, and the plate then washed for a few seconds in warm water. On drying it appeared as a coloured photograph when placed in front of the lens and viewed through the hole in the screen. 1 These gratings were ruled for us on the dividing engine at Cornell University, through the courtesy of Prof. E. L. Nichols. JuNE 29, 1899] NATURE 20t Proper registration during the triple printing is secured by making reference marks on the plates. A picture of this sort once produced can be reproduced indefinitely by making contact prints, since the arrangement of the lines will be the same in all of the copies as in the original. The finished picture is perfectly transparent, and is merely a diffraction grating on gelatine with variable spacing. In some parts of the picture there will be a double grating, and in other parts (the whites) there will be a triple set of lines. Having had some difficulty in getting three sets of lines on a single film in such a way as to produce a good white, I have adopted the method of making the red and green gratings on one plate, and the blue on another, and then mounting the two with the films in contact. It is very little trouble to multiply the pictures once the original red-green grating picture is made. The pictures are viewed with a very simple piece of apparatus, shown in Fig. 4, consisting of a lens cut square like a reading glass, mounted on a light frame provided with a black screen perforated with an eye-hole through which the pictures are viewed. The colours are ex- tremely brilliant, and there is a peculiar fascination in the pictures, since if the viewing apparatus be slowly turned so that its direction with reference to the light varies, the colours change in a most delightful manner, giving us, for example, green roses with red leaves, or blue roses with purple leaves, a feature which should appeal to the impressionists. The reason of this kaleido- scopic effect is evident, for by turning the viewing apparatus we bring the eye into different parts of the overlapping spectra. It is possible to project the pictures by employing a very intense light, and placing a projecting lens in place of the eye behind the perforation in the screen. Of course a very large percentage of the light is lost, con- sequently great amplification cannot well be obtained. I have found that sun-light gives the best results, and have thrown up a three-inch picture on a four-foot sheet so that it could be seen by a fair-sized audience. By employing a lens of suitable focus it is possible to make the viewing apparatus binocular, for similar sets of superposed spectra are formed on each side of the central image by the gratings, so that we may have two eye-holes if the distance between the spectra corresponds to the interocular distance. It is interesting to consider that it is theoretically possible to produce one of these diffraction pictures directly in the camera on a single plate. If a photo- graphic plate of fine grain were to be exposed in succession in the camera under red, green, and blue screens, on the surfaces of which diffraction gratings had been ruled or photographed, the plate on development should appear as acoloured positive when seen in the viewing apparatus. I have done this for a single colour, but the commercial plates are too coarse-grained to take the impression of more than a single set of lines. With specially made plates I hope to obtain better results. R. W. Woop. NO. 1548, VOL. 60] LOCAL UNIVERSITY COLLEGES FOR LONDON. qe adequate provision of university education for London is by no means the simple and straight- forward task which some people seem to imagine. From whichever of the many possible points of view the question of the education of London is considered, the anomalous position which has to be assigned to the greatest city in the world is the most noteworthy result of the invest- igation. If, for instance, an endeavour is made to estimate the comparative facilities offered for higher in- struction in the metropolis with those to hand in other countries and in our own large provincial towns —judged on a basis of population—the results arrived at are as remarkable as they are interesting and instructive. The population of Scotland in 1896 was 4,186,849 ; yet located at Edinburgh, Glasgow, Aberdeen and St. Andrews are four well-equipped and largely endowed universities ; while, in addition to these, is to be found at Dundee a college providing university education, and, though working with St. Andrews, in receipt of an annual grant of 1ooo/. from the Treasury. The population of the county of London was last year 4,504,766. If, as is done in the University of London Act, 1898, the towns within thirty miles of the university buildings are in- cluded, the population must be placed at a very much higher figure, viz. about six millions and three-quarters. So that, keeping well within limits, and running no risk of any charge of exaggeration, the inhabitants of this metropolitan area may be said to considerably out- number those of Scotland. When the universities and university colleges provided for this immense population are enumerated the total is ludicrously small. There is no teaching university, and but three university colleges— University College, King’s College, and Bedford College. Of course, there are other colleges in London ; but, in defining university colleges reference is made to the Treasury Minute of June 2, 1897, dealing with the grant in aid of the university colleges of Great Britain. At University College there were in the faculties of Arts, Laws, and Science, in the session of 1895-6, 747 students, including engineering students. At King’s College, during the same session, there were in Arts and Science 284 day students, 305 evening students, and 315 lady students. At Bedford College, the number of students throughout the same period numbered 176. The total number of persons receiving instruction of uni- versity standing in officially recognised institutions was consequently not much over 1500 during the year 1895-6. If the populations up to date of the eight large towns in England provided with university colleges be added together, the total obtained is about 3,233,765. Similarly, Wales, with a population in 1891 of 1,501,163, has three university colleges, now together constituting the Uni- versity of Wales. Not only in comparison with Scotland, therefore, but also by the side of Wales and the English provinces, London is seen to be extraordinarily deficient in properly authorised establishments the prime duty of which is to provide university instruction. It may be urged at this stage that the work of the University of London Commission now being performed will, as it is intended it shall, completely alter the present unsatisfactory aspect of things, and that ere long pro- visions which will satisfy the most earnest advocate of higher education will be provided. But valuable as the coordination of effort which is likely to result from the inauguration of the new University of London will be, it can hardly be contended that to confer new powers upon certain existing colleges, and to rearrange the work of the staffs of institutions which have previously proved inadequate, will be a complete solution of the proper provision of university instruction for nearly seven millions of people. 202 It may be said at once that London should have a university college in each one of the various parts of the enormous district it covers. If one of the most important phases of the education imparted by the university is the intimate association of the under- graduate with his professors, the free exchange of views ‘between the students themselves, and that mellowing effect which results from the feeling of a close con- nection with the corporate life of an important institution —then surely many small universities are incomparably better than one many-sided and multi-tentacled body with which the individual student can have no personal -connection. Nor is this conception of local universities in the different districts which build up the straggling wilder- ness we call London a dream of Utopia. As has been before pointed out in these columns, there already exist in London eleven polytechnic institutions, and the found- ation stone of a twelfth has been laid. These, with four branches which have been established, provide sixteen separate centres scattered throughout an area which extends from Woolwich to Wandsworth in one direction, and from New Cross to Holloway in another. Why cannot some of these extensive buildings and lavishly furnished lecture-rooms and laboratories, representing half a million sterling in capital outlay, be utilised for the purpose of university work ? A reference to previous issues of NATURE will abundantly prove that there is nothing incongruous in undertaking university education in the lecture theatres, -class-rooms and laboratories of these polytechnics. Com- paratively few additions to the apparatus and fittings already provided would be necessary. Indeed, the work which has already been accomplished, valuable though it is, is scarcely return enough for the munificence of the City companies, the City parochial charities, the London County Council, private donors and others, which has placed the London polytechnics in their present con- dition of complete equipment. A common retort to any such suggestion as has now been briefly stated—that the work of a university college is of a much more advanced nature than any- thing accomplished in a polytechnic—will not bear close examination. Several tests can easily be applied. An inspection of the lists of graduates of the London University, for instance, shows that a comparison of the numbers of successful candidates is all in favour of the polytechnics as compared with the university colleges. As it happens, it is possible to obtain the verdict of former professors of university colleges who are now engaged in the work of the polytechnics, and their assurance is that a greater quantity of advanced work, at all events in science, is done in the polytechnic. Moreover, the amount of work of an advanced type accomplished in English university colleges is usually somewhat exaggerated. A few quotations from a report presented in 1897 by Mr. P. H. Warren, Pre- sident of Magdalen College, Oxford, and Prof. Live- ing, Fellow of St. John’s College, Cambridge, to the Lords Commissioners of her Majesty’s Treasury, will justify this statement. Of one university college it is stated, “On the Arts side it cannot be said that at present any amount of work of a high standard is being done in the college,” or later, ‘“‘most of the work, both in‘arts and science, is of an elementary kind.” Ot another similar place of instruction, “ With regard to the work now being done there, judged by University standards, a good deal of it is of an educational and preparatory rather than of an advanced and learned character.” In the case of another college, “It is, there- fore, not to be wondered at that the work on the Arts side should be still in a somewhat incipient stage, and mainly educational rather than learned.” Of a fourth NO. 1548, VOL. 60] NATURE [JUNE 29, 1899 college it is reported, “A great deal of this work is in the nature of things of a somewhat preparatory kind, and there is throughout the college a great deal of work of not a very advanced character.” Similar re- marks concerning other university colleges might be multiplied, but quotations enough have been made to show that in apportioning the Treasury grant to univer- sity colleges the mere fact that elementary instruction is a part of the work carried on in the buildings is not con- sidered a disqualification for also undertaking university instruction. It is true that a very large part of the instruction of the 50,000 members and students enrolled by the London polytechnics takes place in the evening. This has been urged as evidence of the wide disparity between the methods of polytechnics and those of university colleges, but such an allegation reveals a want of knowledge of the prevalent conditions of instruction in university colleges, The evening classes of King’s College, London, form an important part of the whole work of the institution. At Owens College, Manchester, a very complete system of evening lectures has been arranged for schoolmasters and others engaged during the day. The evening classes at University College, Liverpool, are strong and well at- tended, and are encouraged by the College authorities. The number of evening class students at Mason College, Birmingham, steadily increases. Besides the regular day work of the Bristol University College, there is an extensive system of evening classes, covering almost all the subjects taught in the college. At the Durham Col- lege of Science, Newcastle-upon-Tyne, there were in 1895-6, 1092 evening students compared with 499 day students. At Nottingham, in 1894-5, there were more than three evening students to one attending during the day. Attention has already been called (No. 1523, p. 236) to the very complete arrangements in some of the poly- technics for instruction in the methods of scientific re- search, and to the excellent results, as evidenced by papers read to the learned societies, which have followed the lectures and demonstrations. It would consequently appear that a judicious system of coordination and a little levelling-up would convert some of these sixteen institutions, which in the past ten years have had a phenomenal growth, and are steadily im- proving in status and influence, into satisfactory university colleges, bringing the highest order of culture to the very doors of the so-called metropolitan Philistines. THE PLANS FOR ANTARCTIC EXPLORATION. ie is understood that the German Antarctic expedition for the year 1901 has now been fully organised. A grant of 60,000/. towards the expenses has been made by the Reichstag. Dr. Erich von Drygalski, one of the professors of geography in the University of Berlin, has been appointed the scientific leader, and an influential Committee is charged with perfecting the arrangements. This Committee is anxious that all the plans should be arranged for joint action, so that the German and British expeditions should supplement and reinforce one another at every point, thus ensuring the maximum return of scientific knowledge for the money expended. The ex- pedition of the Valdivia, under the scientific leadership of Prof. Chun, is a proof of the splendid results which attend deep-sea expeditions under a scientific chief, if indeed the Challenger expedition did not supply proof enough. It is, however, still the opinion of some autho- rities in this country that an expedition which has to be carried in a ship must be under the sole and exclusive charge of a naval officer. The subject is one which JUNE 29, 1899] lends itself to discussion, and many illustrations may be adduced in favour of the arguments on either side. It is gratifying to record that a national British expedition, well organised and excellently equipped, will be sent out to co-operate with the German expedition of 1901. That this expedition will be a purely scien- tific one is guaranteed by the fact that the organising body is a Joint-Committee of the Royal Society and the Royal Geographical Society, on which practical oceanographers and representatives of natural science are associated with the older generation of Arctic and Antarctic explorers. A responsible and representative directing body to which the choice of the leaders of the expedition can confidently be left is the first con- sideration, and this has been secured in the Joint- Committee. The first task of this Committee was to ascertain what resources would be available for carrying out the objects of the expedition. Three handsome con- tributions had been received—two of them from private individuals may indeed be termed magnificent—viz. 25,000/. from Mr. L. W. Longstaff, 5000/7. from Mr. A. C. Harmsworth, and 5000/. from the Royal Geographical Society, while other subscriptions raised the total to 40,000/. Representations to the Government had pro- duced no effect when the expedition was merely a pro- ject, but when Mr. Longstaff’s donation made it certain that a British expedition would be equipped, Mr. Balfour, the First Lord of the Treasury, agreed to receive a deputation on the subject. Accordingly, on June 22, a deputation waited upon Mr. Balfour at the Fereign Office, introduced by Sir Clements Markham, President of the Royal Geographical Society, and including Lord Kelvin, Sir Joseph Hooker, Sir Leopold McClintock, ‘Sir Erasmus Ommanney, Dr. A. Buchan, Dr. R. H. Scott, Admiral Markham, Sir Vesey Hamilton, Sir W. White, Dr. Giinther, Prof. Ray Lankester, Sir Michael Foster, Prof. Ricker, Prof. G. Darwin, Sir William Crookes, and a number of members of the Councils of the two Societies. ‘Sir Clements Markham, in introducing the deputation, laid great stress upon the scientific character of the pro- posed expedition. After bringing forward the historical argument of the interest taken by former Governments in polar exploration, and the value of navigation in those seas as a training for seamen and officers, he said (we quote the report in the Zzmes) :— . *Still the avowed object of Government expeditions was scientific research, The objects of the two societies were iden- tical. They were undertaking work which successive gener- ations of our statesmen and naval officers had looked upon as beneficial to the country and to the navy, and for this reason thought they had a claim on the Government for assistance. But further, some of the scientific results required were of imme- diate practical value. Indeed, «all scientific research became eventually, directly or indirectly, practically useful. Much of the Antarctic work would, however, at once be of use to navigation, especially as regarded the magnetic survey.” Sir Joseph Hooker, the last survivor of the great Ant- arctic exploring voyage of the Zyeéws and Terror, under Sir James Ross, supported Sir Clements Markham, and Lord Kelvin followed with the hope that all would be done to bring the enterprise to a triumphant issue. Prof. Ray Lankester spoke of the importance of the biological observations, and especially referred to the question of a bi-polar fauna as one likely to be greatly elucidated by the expedition ; and Prof. Riicker, in conclusion, pointed out how impertant the magnetic survey of the Antarctic area is. Mr. Balfour replied in a sympathetic speech, in the course of which he said :— “J, for my own part, fully recognise that if, as I think, expeditions to the poles of the earth, or towards the poles of NO. 1548, VOL. 60] NATURE 203 the earth, are eminently desirable, both on practical and purely scientific grounds, these expeditions are perhaps even more important when undertaken towards the Antarctic Pole than towards the Arctic Pole, for we certainly know much less at present about the Antarctic regions than we do about the Arctic regions, and the actual area of this unknown but immense portion of the earth’s surface is much larger in the case of the South Pole than in the case of the North Pole. . . . I, how- ever, should not be representing my own personal convictions —and I am speaking in this matter for myself—if I for a moment let it be thought that in my judgment the scientific investigations which directly, immediately, and obviously lead to some practical result are the only ones which it is worthy of a great nation to pursue. I take a different view based partly upon the scientific experience of the world. If our forefathers of the last two centuries—I do not mean men of British origin. alone, but I include the great French expeditions and other expeditions sent out during the last century and during the seventeenth century—had not carried on this work, it is manifest that our ignorance of the planet on which we live would be much more profound than it is at. present ; and it would not be creditable to an age which flatters itself, above all other ages, to be a scientific age, if without reluctance we acquiesced in the total ignorance which now envelops us of so enormous a portion of the southern hemisphere of our planet. For my own part, while I entirely agree with all that has been said upon the important facts and issues which may be anticipated from any expedition, I by no means limit my interest to such practical results. The things which we go directly to observe, and with every intention of observing, are doubtless of the highest import- ance. But I shall be greatly surprised if the expedition does not come across a great many phenomena which we did not expect, and which will throw a novel light upon many of the most import~ ant scientific theories, meteorological, geological, biological and magnetic. If this expedition is sent forth, as I hope it will be, adequately equipped at the date to our satisfaction, when we: shall be able to co-operate with the German expedition, in respect of scientific interest alone such co-operation must be valuable from every point of view, and it will, among other things, have the effect of strengthening, if such strengthening be necessary or possible, the cosmopolitan or international character of these sciences. . I am sure if the Chancellor of the Exchequer were here to-day he would tell you that, in so far as he could meet the wishes of the deputation, such action on his part must be regarded not as a reason for giving something more to some future deputation, but rather as a reason for giving less. But with that caution, which I feel bound to utter on his behalf, I think I should not arouse undue hopes if I say that the Chancellor of the Exchequer will find it in his power to give substantially to the great project which you have in hand. I do not say that the aid given will reach the limits of your largest wishes, but I hope and believe that it will be sufficient to enable us to send out this expedition in a manner not unworthy either of the great societies which have interested themselves in this matter or of those liberal members of the public who have subscribed out of private means to further the object which you have in view, and not unworthy of the country which has done more than any other country in the past to send forth expeditions similar in character to the one which you desire to send forth.” Nothing could be more satisfactory than Mr. Balfour's. view of the claims of research in pure science to public recognition, or his promise that a liberal grant to the Antarctic expedition shall be given by Government. It remains for the Joint-Committee to settle the plan of the expedition and to select the scientific leader on whose qualifications as a man of science and on whose freedom, of action with regard to the executive authority of the ship or ships the success of the expedition as a scientific enterprise will entirely depend. This choice cannot be made too soon, for the details of scientific equipment must largely determine the plan of the ship which has to be built ; and no one can be so well qualified to advise upon and carry out the preparations as the man whose reputation depends on the result of those scientific in- vestigations which every one of the promoters of the expedition has declared to be its exclusive object. 204 CHARLES WILLIAM BAILLIE. WE regret to have to announce the sudden death, at Broadstairs, on June 24, at the age of fifty-five years, of Naval Lieutenant Charles William Baillie, Marine Superintendent of the Meteorological Office, a post which he had held for eleven years. Mr. Baillie was perhaps best known by his sounding machine, which he invented while on the North American Station about 1871, and which is still in use. It is a modification of the apparatus known as the “ Hydra” machine. It was used in the Challenger expedition, and is described in Sir W. Thomson’s book, “The Voyage of the Challenger.” Lieut. Baillie was much employed in surveying, and while in the Sy/z/a, under Captain (now Vice-Admiral) St. John, on the China Station, he was selected by the Admiralty to be Director of Nautical Studies at the Imperial Naval College at Tokio, Japan. The results of his teaching are to be seen in the condition of the Japanese Navy at the present day. After several years of duty in this important post he returned to England on half-pay. In October 1879 he joined the Meteorological Office, so that he had nearly completed twenty years of service in that institution. The principal works which he has carried out there have been the charts of sea surface temperature, of barometrical pressure, and of currents for all oceans. The discussion of the meteorology of the South Indian Ocean, from the Cape of Good Hope to New Zealand, which is shortly about to appear, has been carried out under Lieut. Baillie’s superintendence, while he had laid down the lines of inquiry to be pursued in the work now n hand at the office—the “ Meteorology of the South Atlantic and of the Coasts of South America.” Lieut. Baillie was a Fellow of the Royal Geographical and the Royal Astronomical Societies. He married Miss Conyers, of Bermuda, and leaves a numerous family. NOTES. Pror. W. C. BroécGEr, of the University of Christiania, has accepted an invitation to deliver the second course of the George Huntington Williams memorial lectures at the Johns Hopkins University, in April 1900. He has selected as his subject “ Modern deductions regarding the origin of igneous rocks.” Dr. G. AGAMENNONE has been selected to succeed the late Prof. M. S. de Rossi as director of the important Geodynamic Observatory at Rocca di Papa, near Rome. Dr. Agamennone, who is well known by his numerous seismological papers, has for several years been assistant at the Central Office of Meteoro- logy and Geodynamics at Rome; and, during the years 1895-96, was in charge of the seismic department of the Meteorological Observatory at Constantinople. News has been received of the death of Mr. John Whitehead while on a scientific mission in the Island of Hainan. Mr. Whitehead left England in the autumn of last year for the purpose of exploring the less known islands of the Philippine group and obtaining a collection of their fauna for the British Museum (Natural History). WE learn from Sczezce that President McKinley has ap- pointed a Commission to determine the best route for a canal across the Isthmus of Panama or Nicaragua. The sum of 1,000,000 dollars has been appropriated for the expenses of the Commission, and a number of surveyors will accompany the party which will shortly leave for Colon. Dr. D. G. BRINTON, Professor of American Archeology and Linguistics at the University of Pennsylvania, has presented to NO. 1548, VOL. 60] NATURE [JUNE 29, 1899 the University his entire collection of books and manuscript relating to the aboriginal languages of North and South America, representing the work of twenty-five years, and embracing about 2000 titles. AN excursion to Derbyshire, extending from August 3 to August 9, has been arranged by the Geologists’ Association, The directors of the excursion are Mr. H. H. Arnold-Bemrose, Dr. Wheelton Hind, Mr. J. Shipman, and Mr. J. Barnes, A sketch of the geology of the Lower Carboniferous rocks of Derbyshire will be given by Mr. Arnold-Bemrose at a meeting of the Association on July 7. THE preliminary programme of the thirteenth International Medical Congress, to be held in Paris from August 2 to August 9, 1900, has just been issued from the central offices in the Rue de I’Ecole de Médecine. M. Lannelongue is president of the Congress, and Dr. Chauffard is the secretary-general. National Committees have been formed in each country to further the work of the Congress. The president of the Com- mittee for Great Britain is Sir William MacCormac, Bart., K.C.V.O., and the hon. secretaries are Dr. Garrod, Dr. Keser, and Mr. D’Arcy Power. THE second trade exhibition of photographic and scientific apparatus and sundries will be held in the Portman Rooms, on April 27 to May 5 next year. Intending exhibitors should communicate with the Secretary of the Exhibition, 15 Harp Alley, Farringdon Street, E.C. To celebrate the centenary of the granting of the charter to the Royal College of Surgeons of England in 1800, the Council propose to apply for a supplementary charter. It is proposed to obtain powers to confer the Fellowship of the College on persons of distinction who are not members. A memorial has been drawn up, suggesting to the Council that a favourable opportunity now presents itself for the satisfaction of that desire which has at various periods during the century, and especially during the last fifteen years, been expressed by a large number of the members of the College—viz. that they should be repre- sented on the Council. It is submitted that ‘‘it would be both equitable and politic that the members should have a voice in the conduct of a Corporation of which they are, and always have been, numerically and financially the mainstay.’’ At every annual meeting of Fellows and members (instituted in 1884) this or some similar proposal has been carried practically unani- mously, and a petition in its favour was signed by nearly 5000 members and presented to the Privy Council. The Council have twice taken a poll of the Fellows on the question, but on neither occasion has an absolute majority voted against the proposal, though many were in its favour. THE Academy invited its readers to compose an inscription, of not more than forty words, suitable to be engraved upon the statue of Charles Darwin, just unveiled at Oxford. The best inscription was considered to be that submitted by Mr. Edwin Cardross, viz.: ‘‘ Charles Darwin, the great naturalist, memor- able for his demonstration of the law of evolution in organic life, achieved by scientific imagination, untiring observation, comparison, and research: also for a blameless life, character- ised by the modesty, ‘ the angelic patience, of genius.’ ” AN interesting survival of the very ancient custom of watching the sun rise at the summer solstice was witnessed on Salis- bury Plain on June 21. The Westminster Gazette states that on the night preceding the longest day (June 21) there was a large gathering of people from the neighbourhood, and also from other parts, assembled close to the historic circle of stones at Stonehenge, in order to see the sun rise over the Plain. When atmospheric conditions are favourable, those watching JUNE 29, 1899] NATURE 205 rom the altar stone in the centre of the circle see the sun apparently poise itself for an instant upon the top of the stone known as the Friar’s Heel. This sight is a rare privilege, and as it depends upon a doubtful meteorological condition—a per- fectly cloudless sky at the point and time at which the sun rises above the horizon—those watching anxiously scan the sky, alas! in too many instances, to find that their night’s vigil on the Plain is barren of result. The last time the phenomenon was witnessed was in 1895. THE annual general meeting of the Jenner Institute of Pre- ventive Medicine was held at Chelsea on June 23. The report of the Council for the year was read and adopted. The report states that during the year the work of the institute continued to make satisfactory progress. The internal fittings of the Chelsea building are now completed with the exception of the museum, and the various departments are fully equipped and at work. The meeting received with enthusiasm the reference to Lord Iveagh’s gift of 250,000/. for the promotion of the objects for which the institute was founded. The gratifying announcement was made that Lord Lister had consented to act as chairman of the new governing body that will in future con- trol the affairs of the institute. Dr. Macfadyen’s report upon the general work of the institute during the year was read and adopted. During the year the organisation of work in the main laboratories of the institute was completed, and valuable additions made to the stock of scientific apparatus. The founda- tions of the new wing, which will complete the original plan of the institute, are at present in course of construction. The photographic department is fully equipped, and the necessary illustrations to scientific papers will in future be prepared in this laboratory. At no period has there been a greater body of research work in progress in the institute than at the present moment, and reference is made in the report to the more important investigations being carried on. A number of in- vestigations by Dr. Hewlett and others have been published during the year, anda second volume of the Zyamsactions of the institute is going through the press. As regards the courses of instruction, which have been well attended, the aim has heen to train the advanced student, as is done in foreign faboratories, with a view to subsequent research work. when surrounded by an imperfect vacuum. At the same time, the charge remains below —70° in a Dewar tube, the initial temperature in every case being — 79°. SOCIETIES AND ACADEMIES. Lonpon. Royal Society, May 18.—‘‘ Diffusion of Ions into Gases.” By John S Townsend, M.A. (Dublin), Clerk Maxwell Student, Cavendish Laboratory, Cambridge. Communicated by Prof. J. J. Thomson, F.R.S. In the paper upon this subject the principles of the theory of interdifusion of gases are applied to the diffusion of ions produced in a gas by the action of Rontgen rays. When a gas is ionised in this way, and then removed from the action of the rays, the conductivity gradually disappears. If there are no electric forces acting on the gas, the loss of conductivity is due partly to the encounters between positive and negative ions, and partly the effect of the surface of the vessel which discharges those ions that come into contact with it. : The ions may be considered as a separate gas (A) mixed with the ordinary uncharged molecules (B), which are unaffected by the rays. When the mixture is passed along a metal tube there is a loss of conductivity, due to the ions coming into contact with the surface. A formula is given for calculating the rate of diffusion of the ions A into the gas B from this loss of con ductivity, which was found experimentally. The following values were obtained for the coefficients of diffusion of ions into air, oxygen, carbonic acid, and hydrogen. JUNE 29, 1899] It was found that the rates of diffusion of the positive and negative ions differed more when the gas was dry than when it was moist. Values of « tn Square Centimetres per Second. qg ) « for + ions | « for —ions | « for + ions | « for —ions Gas in dry gas in dry gas | in moist gas in moist gas Air "0274 042 032 7035 Oxygen : 025 0396 | ‘0298 | 0358 Carbonic acid... 023 026 "0245 | ‘o256 Hydrogen 123 *190 Zoe 142 | From the equation of motion 1 pu sake + nXe K ax (where # is the partial pressure of the ions, x the number of ions per c.c., e the charge on each ion, X the electric force at any point, and w the velocity of the ion in the x direction), it can be seen that when a = 0 the velocity 2, due to the electric ES force X, is nXex. If the potential gradient is one volt per centimetre, X = 1 ‘ aa 320 in electrostatic units, and the corresponding value of w is ke 2 “= = 300 Let N be the number of molecules per c.c. in a gas at pres- sure P, equal to the atmospheric pressure and temperature 15 C., the temperature at which ~, and « were determined. The quotient a may be substituted for” in the above equa- tion, and Ne is therefore obtained in terms of qualities which can be determined experimentally. 2 8 Ne=3 1° eae since P = 10° in C.G.S. units. K Substituting for #, the mean velocities given by Prof. Ruther- ford (E. Rutherford, Pz? Aag., November 1897), and for « the mean coefficient of diffusion obtained for the dry gases, and the following values of Ne are obtained :— Air os. Nene be rOL” Oxygen ... Neo = 1°25 101” Carbonic acid Nés = 1-30 101” Hydrogen Nex = 1'00 101° Experiments on electrolysis show that one electrodynamic unit of electricity in passing through an electrolyte gives off 1°23 c.c. of hydrogen at temperature 15° C. and pressure 10° C.G.S. units. The number of atoms in this volume is 2°46 N, so that if E is the charge on an atom of hydrogen in the liquid electrolyte 2°46 NE=1 electrodynamic unit of quantity =3 10!” electrostatic units. Hence NE=1'22 10)", the charge E being expressed in electrostatic units. Since N is constant, these numbers show that the charges on the ions produced by Rontgen rays in air, oxygen, carbonic acid, and hydrogen are all the same, and equal to the charge on an atom of hydrogen in a liquid electrolyte. Prof. J. J. Thomson (J. J. Thomson, Phz/. Mag., December 1898) has shown that the charge on the ions in oxygen and hydrogen, which have been made conductors by Rontgen rays, is 6 10~” electrostatic units, and is the same for both gases. _ Taking this value for the charge e, the number of molecules in a cubic centimetre of a gas is obtained : IN=2: 101%) The weight of a molecule of hydrogen ne therefore 4°5 10-* grammes. In order to prove that the positive and negative ions have the same charge, the ratio of the coefficients of diffusion must be shown to be equal to the ratio of the velocities. This sub- NO. 1548, VOL. 60} NATURE 212 ject has been investigated by Prof. Zeleny (J. Zeleny, //z/. Mag., 1898), and it was found that the negative ion travels faster than the positive ion in air, oxygen and hydrogen, the ratio of the velocities being 1°24 for air and oxygen, 1°15 for hydrogen, and 10 for carbonic acid. Royal Society, June 15.—‘‘On the Orientation of Greek Temples, being the Results of some Observations taken in Greece and Sicily in the month of May 1898.” By F. C. Penrose, M.A., F.R.S. The orientation of the Cabeirion Temple, near Thebes, 01 which the angle has been disputed (see p. 46 in my paper of 1897), was remeasured with the theodolite in May 1898, and the previous observations confirmed. An additional example is added from an archaic Temple of Neptune in the Isle of Poros, introducing the employment of the bright zodiacal star Regulus, which I had not before met with. In Sicily the re-examination of the temples at Girgenti, where, in my former visit, I had relied for azimuth on the sun’s shadow and the time, has enabled me to give to the elements some amendments in detail, the only point of consequence being that the orientation date of the temple named Juno Lacinia is brought within the period of the Hellenic colonisation of that city. The most interesting point in the paper seems to be, that in the case of two Athenian temples, namely, the Theseum and the later Erechtheum—z.e. the temple now partially standing—it is shown that the days of those months on which the sunrise, heralded by the star, illuminated the sanctuary coincided exactly, on certain years of the Metonic cycle, with the days of the Athenian lunar months on which three important festivals known to be connected with at least one of those temples were held. The years so determined agree remarkably well with the probable dates of the dedication of those temples ; and in the case of the first mentioned, the festival, which was named The Thesea, seems to leave little doubt that the traditional name of the temple, which has recently been much disputed, is the correct one. ‘*Collimator Magnets and the Determination of the Earth’s Horizontal Magnetic Force.” By C. Chree, Sc.D., LL.D., F.R.S., Superintendent of the Kew Observatory. Com- municated by the Kew Observatory Committee of the Royab Society. During the last forty years, there have been examined at Kew Observatory upwards of toocollimator magnets used in observing the horizontal force and declination. The ‘‘constants”” of these magnets—temperature and induc- tion coefficients, and moment of inertia—have been determined at the Observatory, and the tables based on these determinations have served to reduce magnetic observations at a large number of the leading magnetic observatories. The present paper deals with the data recorded in the Observatory books for the constants specified above, and with. other quantities—such as the ‘‘permanent ” magnetic moment— which are deducible from the records. It determines the mean: values of the several quantities for the instruments of the leading: English makers, and investigates whether relations do or do not exist between them. It then deduces from the records the probable errors in the values of the several quantities, proceeding on the hypothesis that the methods of determining them are correct. It next examines, from a mathematical standpoint, the accuracy of the formulz employed in reducing horizontal force observations, and, from a physical standpoint, the possi- bility of differences between the quantities determined at the Observatory and the quantities actually concerned in horizontak force observations. The various sources of uncertainty are dealt with, and an attempt is made to ascertain to what extent they may affect the values found for the horizontal force. The results of the paper are of too technical a character to. admit of their being summarised briefly in an intelligible way. Physical Society, June 23.—Mr. T. H. Blakesley, Vice- President, in the chair.—A paper on the magnetic hysteresis of cobalt, by Prof. Fleming, Mr. A. W. Ashton, and Mr. H. G. Tomlinson, was read by Mr. Ashton. A rectangular sectioned circular ring of cobalt was insulated with silk tape and wound over with four secondary coils put on at quadrantal positions. Over these secondary coils six primary coils were placed, and the ring was submitted to a complete set of magnetic tests with a ballistic galvanometer. From these observations various 214 NATURE [JuNE 29, 1899 curves have been plotted, and the results have been compared with a similar set of readings taken on a cast iron ring. and the terminology and nomenclature of the forms of the ocean floor will be discussed by Profs. Wagner, Kriimmel, Voiekoff, and Dr. H. R. Mill. Proposals for the uniform use of the metric system and the centigrade temperature scale in all geographical work will also be put forward. : The scientific excursions, which for the most part pre- cede the meeting of the Congress, have been wel? organised. The programme has just been issued, giving particulars as to route, leaders, terms, &c., and also con- taining a list of the best maps and guide-books, and a 228 bibliography of the scientific literature bearing on each excursion. Most of the excursions start late enough to allow members who have been present at the British Asso- ciation meeting at Dover to attend them, and they all terminate at Berlin in time for the feast of welcome. They are as follows :— (1) Siebengebirge, Rhine, Eifel, Moselle, from Sep- tember 19 to 25, under the guidance of Prof. Bonn and Drs. Philippson and Kaiser. (2) Taunus, Rhine, Nahe, Lahn, from September 21 to 26, conducted by Prof. Sievers, of Giessen. (3) The Vosges, from September 21 to 25, led by Profs. Gerland and Weigand, starting from Strassburg. (4) Thuringia, from September 23 to 27, conducted by Profs. Walther and Regel. (5) The Island of Rtgen, from September 22 to 27, starting from Greifswald, led by Profs. Credner, Cohen, and Deecke. ‘5) East and West Prussia, starting from K6nigsberg, and led by Profs. Jentzsch and Conwentz, from September 22 to 27. (7) Glacial excursions in the North German Plain will be made to Riidersdorf, near Berlin, on October 1, and from Hamburg along the Baltic shores, from October 7 to 11, under the charge of Prof. Wahnschaffe and Drs. Keilhack and Miller. All communications as to the Congress or the ex- cursions should be addressed to ““The Seventh Inter- national Geographical Congress, 90 Zimmerstrasse, Berlin, S.W.” SCIENCE AT THE WOMEN’S INTER- NATIONAL CONGRESS. Pee Science Section of the Women’s Congress was held at the Small Hall in the Westminster Town Hall on Thursday, June 29, with Mrs. Ayrton in the chair, in the presence of a large and attentive audience. The proceedings were divided into two classes—the work of women in the physical sciences, and the work for women in the b ological sciences. Astronomy was represented by Mlle. Klumpke, head of one of the departments at the Paris Observatory; geology by Miss Raisin, of Bedford College ; chemistry by Miss Dorothy Marshall, of Girton College ; bacteriology by Mrs. Percy Frankland ; and botany and zoology by Miss Ethel Sargant. The work already accomplished by women in these various branches of science was dealt with by most of the speakers, as also the openings for women who desire to take up science as a profession. Mrs. Ayrton, in the course of her interesting and able address, pointed out that there was an important outlet for the work of women at the present time in the manufacture of electrical apparatus, the demand for electrical instruments being so great that manufacturers were not able to cope with it, and an opportunity was now offered for women with the necessary education, energy and capital to start a factory for this purpose. The subject of research work was also discussed, and stress was laid upon the fact that, inasmuch as the majority of students who take up science do so either as an avenue to a degree or with the idea of earning a livelihood by teaching later on, their training was as a rule insufficient and quite inadequate to permit them to undertake independent original work ; whilst on the other hand the demands upon their time made by teaching was so great as to leave practically no leisure for higher work, even when they were qualified to do it. Until this condition of things is altered, and until more women are attracted towards science for its own sake, and not as a means to an end, the contribution of women in the shape of original work must necessarily be limited. It was highly satisfactory to find that, in the open discussion which followed, an attempt on the part NO. 1549, VOL. 60] Na ORE [JuLY 6, 1899 of two speakers to introduce the question of vivisection from the anti-vivisectionist point of view was not tolerated by the audience, these speakers being refused a hearing. It is not too much to say that the papers contributed were worthy both of their subjects and their authors, and that there was a refreshing absence of the hackneyed com- parison of the relative position and intellectual powers of men and women, which has been such a favourite theme with so many speakers at this Congress. The next International Congress of Women will be held five years hence in Berlin. NOTES. WE notice with much regret the announcement that Sir William H. Flower, K.C.B., F.R.S., late Director of the Natural History Departments of the British Museum, died on Saturday, July 1. Tue Albert Medal of the Society of Arts for the present year has been awarded by the President and Council to Sir William Crookes, F.R.S., ‘* for his extensive and laborious researches in chemistry and in physics, researches which have, in many in- stances, developed into useful and practical applications in the arts and manufactures.”” The Swiney Prize, awarded every fifth year for a work on jurisprudence, has been awarded to Dr. Dixon Mann for his book on ‘‘ Forensic Medicine and Toxi- cology.” Ar the annual meeting of the Société nationale d’Acclimat- ation de France the Isidore Geoffroy Saint-Hilaire Grand Silver Medal was awarded to Prof. J. Cossar Ewart, of the University of Edinburgh, for his zebra hybrid work, and to Miss Eleanor A. Ormerod for her work in entomology. Pror. Morssan has been elected a foreign member of the German Electro-chemical Society. THE Premier of Queensland has announced that he intends to ask the Queensland Parliament to grant 1ooo/. in aid of the proposed Antarctic exploration expedition. A Crvit List Pension of 602 per annum has been granted to Mrs. Kanthack ‘‘in consideration of the eminent services rendered to science by her late husband, Dr. A. A. Kanthack, professor of pathology in Cambridge University.” At Berlin, on June 27, Prof. Virchow opened the new patho- logical museum which bears his name and has been built under his superintendence. It has cost about 560,000 marks, and contains a collection of more than 20,000 specimens, collected almost wholly by Prof. Virchow himself, and representing the history of pathology during the past half-century. WE learn from Scéerce that Mr. Secretary Long has appointed a Board of Visitors to examine and report upon the U.S. Naval Observatory, to consist of Mr. Wm. E. Chandler, Mr. Alston G. Dayton, Prof. Geo. C. Comstock, Prof. Geo. E. Hale, and Prof. Edward C. Pickering. THE prize of 500 guineas, offered by the Sulphate of Am- monia Committee for the best. essay on ‘‘ the utility of sulphate of ammonia in agriculture,” has been awarded by the judges— Mr. J. Bowen-Jones, of Shrewsbury, and Dr, J. Augustus Voelcker, of London—to Mr. James Muir, formerly professor at the Royal Agricultural College, Cirencester ; subsequently at the Yorkshire College, Leeds; now County Instructor in Agri- culture to the Somerset County Council. Seventy-three essays were sent in. WE learn from the Zamcet that the Senatus Academicus of the Clark University, Worcester, Massachusetts, which is about to commemorate the anniversary of its foundation, has invited Jury 6, 1899] INO IA OP ce a 229 ——_—__ Prof, Angelo Mosso to deliver a lecture on a subject specially chosen for the occasion, and dealing with a scientific problem of present and universal interest, and Italy, to judge from her leading organs, professional and lay, is deeply sensible of the honour. Prof. Mosso started for the United States on June 20, and has chosen as his theme ‘‘I Processi Psichici ed il Movi- mento” (the Psychic Processes and Movement). Tue death is announced of Mr. Henry Wollaston Blake, F.R.S., at eighty-four years of age. Mr. Blake was an original member of the Institution of Civil Engineers, of the Institution of Mechanical Engineers, and of the British Association. He was elected a Fellow of the Royal Society in 1843. THE forty-eighth meeting of the American Association for the Advancement of Science will be held at Columbus, Ohio, on August 21-26, under the presidency of Prof. Edward Orton. The first general session will as usual be held on Monday morning, August 21, when the president-elect will be introduced by the retiring president, Prof. F. W. Putnam, and addresses of welcome will be made by the Governor of Ohio and the Mayor of Columbus. The addresses of the vice- presidents will be given on Monday afternoon, and the address of the retiring president in the evening. The several sections will meet as usual during the week, and Saturday will be devoted to an excursion, probably to the mounds at Fort Ancient, the coal mines in Hocking Valley, and the natural- gas fields. Further information may be obtained from the permanent secretary of the Association, Dr. L. O. Howard, Cosmos Club, Washington, D.C., and from the local secretary, Prof. B. F. Thomas, Ohio State University. THe annual general meeting of the Marine Biological Association was held in the rooms of the Royal Society on June 28. The president, Prof. E. Ray Lankester, F.R.S., occupied thechair. The Council reported that the laboratory at Plymouth continued in a state of efficiency, and was adequately equipped with the most modern requirements for marine biological re- search. The investigation of the natural history of the mackerel, commenced last year by Mr. Garstang, had been continued, and a report on the variations, races and migrations of this fish had been published. A systematic study of the physical and bio- logical conditions prevailing in the waters at the mouth of the English Channel had also been commenced, which it was hoped would throw light on the causes which determine the move- ments of migratory fishes. The examination of the fauna and bottom deposits between the Eddystone and Start Point had been concluded by Mr. Allen, the director of the laboratory, and a report on the subject had appeared in the /ozrna/ of the Association. Seventeen naturalists and eleven students had worked in the laboratory, in addition to the members of the regular staff. The following were elected members of Council for the year:—President, Prof. E. Ray Lankester ; hon. treasurer, J. A, Travers; hon. secretary, E. J. Allen; Council, F, E. Beddard, Prof. F. Jeffrey Bell, G. P. Bidder, G. C. Bourne, G. H. Fowler, S. F. Harmer, Prof. W. A. Herdman, Prof. S. J. Hickson, Prof. T. Johnson, J. J. Lister, D. H. Scott, Prof. C. Stewart, Prof. D'Arcy Thompson, Prof. W. F. R. Weldon. Ir is the opinion of many meteorologists that daily telegraphic reports from Iceland would be of inestimable value in weather predictions for Great Britain and northern Europe. The com- mercial intercourse with Iceland would, however, evidently not pay the interest on the cost of the cable, and it is only quite lately that the Danish meteorologists have received from business men a proposition, already mentioned in these columns, that makes the project seem at all feasible. The proposition is NO. 1549, VOL. 60] referred to by Prof. Cleveland Abbe in the Monthly Weather Review. It is as follows:—The ‘‘ Grande Compagnie des Télégraphes du Nord,” having its centre at Copenhagen, has undertaken to build and to maintain a line from Shetland, touching the Faroe Islands and ending at Iceland, if an annual revenue of 13,500/. is guaranteed for the first twenty years only. The Government of Denmark and Iceland will establish and maintain the meteorological stations and the expense of daily telegraphic bulletins, and will perform the hydrographic work necessary in connection with the laying of the cable, and will also guarantee an annual subvention of 5000/7. for twenty years. Therefore, all that now remains to be done in order to secure telegraphic communication with Iceland for commercial and meteorological purposes is to secure the re- maining annual income of 8500/. It is hoped that a large portion and perhaps all of this may be secured by national legislation in the States of Europe and America that are interested in this subject. It is announced in Scéence that Mr. Charles H. Senff has given 5000 dollars to the zoological department of Columbia University for purposes of exploration and publication. Mr. Harrington and Mr. Sumner expect, with the assistance of this fund, to make a second expedition to the Nile in search of Polypterus. The fund will also be used for the publication of a memoir on the anatomy of Polyfterus, to be undertaken conjointly by Messrs. Dean, Harrington, McGregor, Strong, Herrick and Prof. Wheeler, of the University of Chicago. THE inaugural lecture on the possibility of extirpating malaria from certain localities by a new method, delivered by Major Ronald Ross at the Liverpool School of Tropical Medicine, is published in the Brétish Medical Journal. According to Major Ross’s observations in India, human malaria isnot conveyed by mosquitos of the genus Culex, but by members of the genus Anopheles. Species of the former genus are generally able to breed in pots and tubs of water, cisterns, wells, and drains— that is, they seem to prefer artificial collections of water of this character to natural collections, such as rainwater, puddles, and ponds. In the case of the other genus, Anopheles, however, the larvee are scarcely ever to be found in vessels and other artificial collections of water, but only in natural ponds and puddles. But whether the dangerous mosquitos prove to be confined to the genus Anopheles or not, it appears certain that they breed in puddles, and are not of the common domestic kind. The practicability of eradicating malaria in a locality by the extermination of the dangerous mosquitos in it thus depends on a single question—Do these mosquitos breed in spots suf- ficiently isolated and rare to be dealt with by public measures of repression? It isto obtain information upon this subject that an expedition to the West African coast is being organised. If it can be shown by accurate investigation that all the malaria in a large town arises from a few small puddles which can be obliterated at small expense, the value of the discovery could not easily be over-estimated. THE Meteorologische Zeitschrift for June contains a brief note of the results of some important observations made by Dr. J. Tuma in seven balloon ascents, for the purpose of obtaining measurements of the distribution of atmospheric electricity in clear weather, and of determining whether the balloon itself re- ceived electrical charges. The first question is of purely scien- tific importance, and the second is of practical interest, as lately the burning of some balloons has been attributed to electrical discharges. The observations show that the positive potential decreases with increasing height; the positive charges are, therefore, accumulated in the lower strata of the atmosphere. During the four last ascents, Dr. Tuma was unable to find that 230 NATURE [JuLy 6, 1899 the balloons were electrically charged. The details of the in- vestigation were published in the Sztzwngsberichte of the Vienna Academy in March last. 3 So many attempts have been made to produce photographic pictures in natural colours, that a bibliography of recent contri- butions to the subject is distinctly valuable. Mr. Philip E. B. Jourdain gives such a bibliography in Photography of June 22. His paper supplements similar bibliographies prepared by Mr. Bolas, the chief additions being a fuller account of Edmond Becquerel’s work, and abstracts of two important papers by Clerk Maxwell and Lord Rayleigh on different branches of the subject. A number of processes, in addition to those known to most men of science, are described. The bibliography carries the subject to the end of 1898, so Mr. R. W. Wood’s process (see p. I19) is not included. THE property that the locus of the poles of an arbitrary plane with respect to the conics of a Steiner’s surface is another Steiner’s surface has been investigated by Lie, Koenigs, and Brambilla. In a communication to the fRezdéconto of the Naples Academy (v. 4), Prof. Domenico Montesano has dealt with the following questions connected with this problem ;— (1) In what relation of position are the two surfaces? (2) Whether the relation is invertible? (3) What forms are de- scribed by the double lines, the triple point, and the double tangent planes of the new Steiner’s surface when the arbitrary plane is varied? In order to answer these questions, Prof. Montesano examines the correlative questions for the surface of the third order with four double points, making these depend on other more general questions relating to a surface of the third order without singularities. In the Bulletin tnternational of the Cracow Academy, M. P. Rudski applies the well-known problem of the elastic sphere under given surface-tractions to calculate the radial displace- ments of the earth’s surface under the weight of ice-caps. There are strong reasons for believing that during the glacial period large areas of land were submerged, which at the present time are at considerable altitudes above the sea-level, and M. Rudski’s object is to test whether these displace- ments of the shore-line can be accounted for by the dis- tortion of the earth due to circumpolar ice, assuming the total quantity of water on the earth’s surface to be constant. M. Rudski considers the test case of uniform ice-caps extending down to latitude 60°, and he assumes the rigidity of the earth to be the same as that of steel. The deformations are different according to whether glaciation exists about one or both poles, the depressions at the poles being respectively 347°1 and 497°8 metres for an ice-cap 2000 metres thick. Moreover, with bipolar glaciation the displacement of the shore at the edge of the ice-caps is negative, while with unipolar glaciation it is positive but smaller. In either case, supposing fiords to extend inwards into the ice-caps, the shore-displacements towards the centre of the caps would be positive. Ir is well known that the influence of a magnetic field in general increases the electric resistance of the rarefied gases, except when the lines of electric and magnetic force coincide. Profs. Elster and Geitel, writing in the Verhandlungen of the German Physical Society, describe an experiment showing that a magnetic field has a similar effect on the conductivity im- parted to air by the influence of Becquerel rays. Experiments have also been made by the same writers, showing that the observed results were not attributable to any deviation produced in the rays by the magnet, but that Becquerel rays, like Rontgen rays, possess the property of not being deflected by magnetic force. NO. 1549, VOL. 60] In the last number of the Zertschr. Wass. Zool., Mr. L. Johann notices certain peculiar epidermal structures occurring at thé base of the spines of one of the spiny dog-fishes (Spinax niger), which he believes to be luminiferous. They take the form of brown or black spots, which are not shining, and are situated on a dark ground. Although distinctly visible to the naked eye, they are seen better through a lens; and, owing to the nature of the skin, are more clearly displayed in the embryo than in the adult. When sectionised and examined microscop- ically, they are found to contain pigment. A tropical repre- sentative of the same family (Zs¢s¢ius brasdliensis) is already known to possess luminiferous properties, and the author there- fore considers that the spots in the Mediterranean species have the same function, By a fortunate coincidence, as his paper was passing through the press, Mr. Johann received a com- munication from Dr. Beer, of the Zoological Station at Naples, Stating that a specimen of Sfznax niger had recently been captured and brought to the aquarium there. Although wounded and in a generally feeble condition, it emitted a distinct luminosity, which would doubtless have been stronger had the fish been in robust health. The author’s conclusions as to the function of the dermal spots are, therefore, demon- strated by actual experiment to be correct. STUDENTs of the Batrachians will be much interested to read in the Proc. U.S. Nat. Mus. Dr. Stejneger’s account of the dis- covery ofa North American representative of the family of disc- tongued frogs (Déescog/ossedae), hitherto supposed to be confined to the northern half of the Old World and New Zealand. The determination rests on a single specimen discovered in the western portion of Washington State, which is considered to belong to a new generic type (Ascaphus). THE July number of the Century Magazine contains an exceedingly well-written and well-illustrated article describing a rocky islet in the Gulf of St. Lawrence known as ‘‘ Bird Rock,” and now utilised as a lighthouse station. From the accounts of early visitors to the rock (among whom was Audubon) it appears that the number of sea-birds—such as gannets, guille- mots, puffins, razorbills and petrels, with which it was covered — was almost incredible, Dr. Bryant, who paid a visit in 1860, estimating the number of gannets alone at one hundred and fifty thousand. Although, to one who has not read the old accounts, the rock would even at the present day appear a marvellous example of the exuberance of bird-life, it is only too certain that unchecked plunder of the eggs and destruction of the adults are steadily tending towards the extermination of the feathered hosts. By all means, therefore, let the Government con- cerned forthwith take the simple steps suggested by the author as essential to ward .off the occurrence of such a dire calamity. : THE useful series of ‘‘ Manchester Museum Handbooks” has received an important addition in the form of an ‘‘ Index to the Systema Naturae of Linneus,’ by Mr. C. D. Sherborn. Needless to say, this work is executed with the thoroughness and care characterising all the efforts of its author. Whether, however, it will ‘“‘help in bringing about that uniformity of nomenclature which is the great need of zoological science at the present day,” the future alone will show. There may also be two opinions as to whether Linnzeus, the founder of our nomenclature, ‘‘had no more power to alter a name once founded than has any other person.”—The ‘‘Guide to the Natural History Collections” in the same series is so well written, and contains such a large amount of information in such a very small compass, that it will prove useful to many besides actual visitors to the museum. i Juty 6, 1899] NATURE 231 SLOWLY but surely is our information as to the former exten- sion of the range of the Saiga antelope of the Volga steppes tending towards completeness. The latest addition to the remains of this animal is a skull from the superficial deposits of Kulm, recently added to the museum at Dantzic. This speci- men, which has been identified by Dr. A. Nehring, is the second hitherto obtained in Germany. As our readers may remember, an imperfect skull was dug up a few years ago near Twickenham. To the last number of the Proceedings of the Royal Physical Society of Edinburgh Messrs. W. S. Bruce and W. Eagle Clarke communicate a paper on the mammalia and birds of Franz-Josef Land. That such a desolate region would have but few land mammals was only to be expected, and the Polar bear and Arctic fox are the only two actually met with, although there are reports as to the occurrence of a hare, and the reindeer is represented by accumulations of its antlers, which were prob- ably carried to their present position years ago by ice-floes. On the other hand, the birds number at least two-and-twenty species. Mr. F. Turner reprints, from the Proceedings of the Austra- lasian Association for the Advancement of Science, a paper on the supposed poisonous plants of South Australia. THE most recent numbers received of the Avéologesches Centralilatt contain a continuation of Dr. Keller’s useful epitome of the results of recent researches in vegetable physi- ology and biology, as well as several original papers in different departments of zoology and botany. WE learn, from an article in the Board of Trade Journal for June, that the source of the india-rubber exported from Peru through Para has been determined by M. Hubert, a botanist on the scientific staff of the Museum of Para, to be a species of Castilloa, possibly identical with the Casti//oa elastéca of Central America. THE TZyazsactions of the British Mycological Society for «897-1898 contain several interesting papers on British Mycology, but some of them are (admittedly) reprints, and, with regard to the others; there is no information as to the date or place where they were read, or even any note of the meetings of the Society. No date even is given to the delivery of the **President’s Address.” The officers of the Society appear to be a President, an ‘‘ Acting President,” and an Honorary Secretary and Treasurer. WE have received vol. i. No. 3 0. the Communicaciones del Museo Nacional de Buenos Aires. It contains:a paper on the Coleoptera of Tierra del Fuego, and some short articles on botany, geology and nomenclature. AN important paper, by Dr. Philip P. Calvert, on Odonata from Tepic, Mexico, with supplementary notes on those of Baja, California, has appeared in the Proceedings of the California Academy of Sciences (third series, Zoology, vol. i. No. 12). Detailed descriptions are given of many of the species. THE thirteenth volume (new series) of the Geographevcal Journal, containing the six numbers of the /Jowrna7 issued this year, has just been published. The papers printed in the volume ; the record of geographical events and investigations ; and the monthly bibliography of current geographical literature, make the volume, like previous ones, essential to the library of the student of geography. THE second part of the first volume of the Azzals of the South African Museum has reached us. Among the papers in- cluded in it are: a descriptive list of the rodents of South Africa, by Mr. W. L. Sclater; a further contribution to the NO. 1549, VOL. 60] South African Coleopterous fauna, by Mr. L. Péringuey ; the South African species of Peripatidze in the collection of the South African Museum, by Dr. W. F. Purcell ; and a descrip- tion of a new genus of Perciform fishes from the Cape of Good Hope, by Mr. G. A. Boulenger, F.R.S. A THIRD edition, considerably enlarged, of ‘ Metal-Plate Work,” by Mr. C. T, Millis, has been published by Messrs. E. and F, N. Spon, Ltd. The volume shows how nearly all the patterns required by sheet-metal-workers can be set out on general geometrical principles. The book has proved of great value to pattern-makers since it was first published twelve years ago, and as the system of construction set forth in it is now regarded as the best means of making the practical man familiar with the geometrical principles underlying his work, the volume should be even more widely used in the future than it has been in the past. THE additions to the Zoological Society’s Gardens during the past week include a Common Paradoxure (Paradoxurus niger) from Java, presented by Mr. J. Osborne; a Barbary Mouse (Alus barbarus) from Barbary, presented by Miss Lyell ; a Cor- morant (Phalacrecorax carbo) from Scotland, presented by Mr. Percy Leigh Pemberton ; two Carrion Crows (Corvus corone) British, presented by Lieut.-Colonel Vilett Rolleston ; a Rock Thrush (Montzcola saxati/is), European, a Yellow Hangnest (Casstcus persicus) from South America, presented by Mr. H. J. Fulljames; twelve African Walking Fish (Perdopthalmus koelreutert) from West Africa, presented by Dr. H. O. Forbes ; a Brown Mouse Lemur (Chirogaleus miliz), two Elegant Galidias (Galidia elegans) from Madagascar, a Red-bellied Tamarin (Jfédas labtatus) from the Upper. Amazons, two Mexican Conures (Conurus holochlorus) from Mexico, a Tabuan Parrakeet (Pyrrhulops?s tabuensis)|from the Fiji Islands, de- posited ; a Wapiti Deer (Cervus canadensis, 8), a Great Eagle Owl (2ub0 maximus), bred in the Gardens. OUR ASTRONOMICAL COLUMN. ComEY 1899 @ (SwiFrt).—This comet, after passing peri- helion, showed such a definite increase of brightness and other evidence of internal action, that its progress was closely watched at several observatories (Astronomical Fournal, No. 464, vol. xx. pp. 60-61). Prof. E. E. Barnard, observing it on May 20 and several succeeding occasions, with the 40-inch refractor of the Yerkes Observatory, found the head of the comet to be distinctly dowb/e, the smaller component being south preceding with reference to the main body. From successive measures it was found that the position angle was gradually decreasing, while the distance between the two nuclei was increasing from 28"°84 on the 20th to 3816 on the 23rd. Though no tail was visible to the eye, a photograph obtained on May 18 showed a slender tail 6° or 8° long. Prof. C. D. Perrine also secured several observations with the 36-inch Lick refractor, confirming the duplex character. of the head of the comet. The two nuclei were estimated to be of the 80 and 9‘5 magnitude respectively, and neither appeared stellar with power of 270. The following continued ephemeris is given by Dr. A. Stichtenoth in Astr. Mach. (Bd. 149, No. 3574) :— Ephemeris for 12h, Berlin Mean Time. 1899. R.A. Decl. Br. eens) S) ey July 6 14 16 54 +17, 16°54 .. LOZUE 15 29 16 12°6 > 10 M4e2Oe 5, 15/1350 008 12 13 26 14 17°3 14 12 43 13 24°9 0°06 16 ed ae) 12 35°6 18 TS 2) II 49°2 0'05 20 14 II 40 +1I 52 232 TEMPEL’s CoMET 1899 ¢ (1873 II.). Ephemeris for 12h. Paris Mean Time. 1899. R,A. Decl. Br. h m. Ss. ive a 4“ July6 ... 20 22 29°7 Sift Wh" 1) Pe 23) A ALTE Wney aL 8 5)027) 3/008 Sa. 24 593 12 4 37 Ons 26 13°6 12 31 29 TOmy-c: Cah Pals) | task, UB GOL Ti PL ice 28 VAle2, em OLS e27 02 ieee 2O 120 + 2075405) ety 5159 13H. ZOMG Te 7 :ON es. Anh 22 Hotmes’ Comer (182 III.).— Ephemeris for 12h. Greenwich Mean Time. 1899. R.A. Decl. Br. heen ss. a i July 7 1 $7 534 - +2517 1 9 2 MONS6200 ee 25 ¢5 037, 0°0386 II 3 585 eee 20 204 13 as A Ot 15 9559 .. 273428 0°:0398 17 eee Bee a 8 26 19 15 44° ven ord eTa 21 2 18 35'5 . +2915 53 0'0412 Maxima OF Mira.—Mr. A. A, Nijland, of Utrecht, com- municates to Astr. Nach. (Bd. 149, No. 3576) an account of his observations of Mira during the apparition in 1898. During the period extending from August 9, 1898, to March 5, 1899, sixty-one observations of magnitude were obtained. The light curve being plotted from these gives the time of maximum as October 4, 1898, this being very close to the predicted time given by Chandler in his third catalogue. The following table shows the observed and calculated times of the last three maxima :— Observed Calculated Retard- Magni- Period. maximum. Chandler III. ation. tude. Days. Days, 1897 Jan. II 1896 Dec. 13 29 3°70 oe 1897 Nov. 26 1897 Nov. 9 17 3°24 ore 1898 Oct. 4 1898 Oct. 6 —2 2°91 2 THE NEw ALGOL VARIABLE IN CyGNUS.—Harvard College Observatory Circular (No. 44) contains the results of a detailed examination of all the Draper memorial plates covering the region of the variable star BD + 45°°3062, discovered by Mdme. Ceraski at Moscow (see NATURE, vol. lx. p. 114). Altogether 195 plates show the star, on 170 of which it is at its full bright- ness, while 20 show it below its normal magnitude. A full discussion of these plates resulted in the determination of the period of the variable to be 4d. 13h. 45m. 2s. It is noticeable that the variation in brightness of this star amounts to about three magnitudes, and therefore exceeds that of any Algol star hitherto discovered. Like all other Algol stars, its spectrum is of the first type. A table showing the times of minima for the remainder of the year is included in the Czrcular. THE HOUSING OF THE OFFICES OF THE UNIVERSITY OF LONDON. ‘THE history of the negotiations which have taken place be- tween the Government and the Senate of the University of London, relating to the proposal of the Government to pro- vide accommodation for the University in the Imperial Institute building, is contained in the subjoined extracts from the Report of the Special Committee appointed by the University to confer with representatives of the Treasury and of the Imperial Institute upon the matter. At a meeting of the Senaté held on December 7, 1898, a letter from Sir Francis Mowatt to the Vice-Chancellor (Sir Henry Roscoe) was read, stating that it had been suggested to the Cabinet that an arrangement might be possible by which an adequate and dignified home for the University of London could be provided in the Imperial Institute buildings, subject NO. 1549, VOL. 60] NAGORE [JuLy 6, 1899 to some extension and internal alterations, if terms could be offered which would be acceptable to the authorities of the Institute. The terms submitted to the Senate of the University are as follows :— ““The Government will provide adequate and suitable ac- commodation for the University of London, as constituted by the Act of last Session, in the buildings of the Imperial Insti- tute, such accommodation to include examination rooms and laboratories either in the building itself or in a new building to be erected immediately adjoining it. ““The Government will undertake the entire cost of the up- keep and maintenance of the buildings, including their protec- tion from fire. : ‘“*The works necessary for providing the acccmmodation in the Institute buildings, corresponding to that now enjoyed by the University in Burlington Gardens—and including the new laboratories—will be put in hand at once; and the head- quarters and offices of the University, as at present constituted, will be transferred from Burlington Gardens as soon as possible after the new accommodation is ready for their reception. ‘©The accommodation in the Institute buildings required for the teaching side of the University will be prepared in antici- pation of the date at which the provisions of the Act of last Session come into full operation, ‘« 4 Committee consisting of representatives of the University, the Treasury, and the First Commissioner of Works, should be appointed forthwith to inquire and report as to the necessary alteration and adaptation of the Institute buildings for the purposes of the University.” After a brief statement of the scope and object of this offer, the discussion upon the proposals was adjourned. There seemed to be some uncertainty in the minds of certain of the Fellows as to the precise terms upon which the proposed joint occupation of the buildings of the Imperial Institute were to be arranged as between the Government on the one hand and the University and the Imperial Institute on the other. It was felt that if a statement could be made upon certain points raised in the discussion such statement would be of signal service in clearing away any misapprehension which might have arisen. The following inquiries were therefore sent to Sir Francis Mowatt, and, with the replies, were read at a meeting of the Senate on February 1 :— “‘1, Is it to be understood that the Government proposes to take over the whole of the present building of the Imperiab Institute for the use of (a) the University of London, (4) the authorities of the Imperial Institute ? “2, Will the University (in case the proposals are carried out) be the tenants of the Government under identical con- ditions as to fixity of tenure, maintenance, &c., as heretofore in Burlington Gardens ? ‘© 3. Is it understood : ‘«(a) That the University will become possessed for its sole use of so much of the Institute buildings as the Government shall decide, after communication with the University of London, to be sufficient for its present and prospective accommodation ? “¢(6) That the University shall have the first use of such halls, corridors, galleries, as are necessary for carrying on its work of examination ? “¢(c) That all concerts and other entertainments in the In- stitute are to be abolished ? “*(¢) That a suitable entrance to the University portion of the building will be provided after due communication with the architect ? : “‘(e) That all educational work of University character carried on within such portion of the building handed over to the Institute authorities shall be under the direct contro} of the University ? *«(f) That proper accommodation will be provided for the University examinations in practical science either in the Imperial Institute buildings or in others to be built outside as may be decided on after further discussion ?” The reply, dated Christmas Day 1898, was as follows :— ‘Tt is not the intention of the Government that any of the three parties should enter on the proposed inquiry with their hands tied. Their sole wish is that the University, the Institute, and the Treasury should meet and discuss whether azy, and, if any, what arrangement is possible, under which the University could be suitably housed, and under suitable conditions, in the a JuLy 6, 1899] present Institute buildings. If the result of the discussion is to show that no suitable arrangement is practicable, the University will be in no way prejudiced by having shown its readiness to discuss the project in a friendly spirit. It will be quite open to the Senate to make an express reservation in the above sense a condition of sending its representatives to sit on the Committee. “The answer to the first and second questions is yes. “* As regards the third, the answers are— sai(@)iWes, “*(6) I am not sure that I quite understand the meaning of the words ‘ the first use,’ but if the following definition will meet the views of the Senate, I can answer the question in the affirm- ative, viz. ‘Full and exclusive use and control at all times at which the said halls are required for the purposes of examination.’ “The regulations for giving effect to this condition will be drawn up by the Treasury, who will be responsible for seeing that they are carried out. ‘*(c) The representatives of the Institute have assured me that the entertainments and concerts will not again take place, but it will be quite open to the Senate to safeguard themselves by making the discontinuance of such things a condition of their presence on the Committee. ‘* The answers to (d), (e) and (/) are in the affirmative.” The views of Convocation upon the proposals are contained in the following letter from the Clerk of Convocation to the Registrar, read at the meeting of the Senate :— ““T am directed by the Special Committee of Convocation, appointed to communicate with the Statutory Commission and the Senate, to request you to inform the Senate that the Committee having had their attention directed to the subject of the proposed transference of the University to the Imperial Institute, adopted the following resolution :— ‘That, in the opinion of this Committee, the Imperial Insti- tute would furnish an adequate and dignified home for the University, provided that the exclusive and permanent control of the whole or a distinct and sufficient portion, with an adequate entrance, and with security of tenure, be vested in the University.” On the motion of the Vice-Chancellor, seconded by Lord Kimberley, it was then resolved : “That with reference to the correspondence between the Vice-Chancellor and Sir Francis Mowatt, the Senate do agree to join in the Conference therein mentioned upon the terms generally set forth in the correspondence, and without prejudice to the ultimate action of the Senate, and that accordingly three Fellows be nominated as a Special Committee of the Senate to serve on the Conference, and to report to the Senate the result of the Conference.” The following Fellows were nominated Members of the Special Committee :—The Vice-Chancellor, Lord Kimberley, and Sir Joshua Fitch. At the next meeting of the Senate, on February 22, further correspondence was presented. It was announced that the Lords Commissioners of Her Majesty’s Treasury had selected the undermentioned gentlemen to represent them at the Con- ference :— Sir F. Mowatt and Mr. S. E. Spring Rice, both of the Treasury, and Mr. Almeric Fitzroy, Clerk of the Council. The following Treasury Minute, dated February 16, 1899, was read :— “*The First Lord and the Chancellor of the Exchequer state to the Board that Her Majesty’s Government have had under consideration the possibility of an arrangement with the authorities of the Imperial Institute whereby a dignified and suitable home may be provided in the Institute buildings at South Kensington for the University of London, as reconsti- tuted by the Act of last Session. The accommodation would include the sole occupation and control of rooms and offices fully equal in number and dimension to those now in the possession of the Senate at Burlington Gardens; examination rooms and laboratories either in or immediately adjoining the existing building ; and also such provision as may hereafter be needed for the full extension and development of the University under the statutes and regulations made by the Commissioners appointed by the Act. ‘*The First Lord and the Chancellor of the Exchequer state that, as the result of negotiations which have taken place between representatives of the University, the Institute and the Treasury, NO. 1549, VOL. 60] NATURE 233 there is reason to hope that an arrangement meeting all the re- quirements of the several interests is now possible ; and they recommend to the Board that the authorities of the University and the Institute should be invited to nominate representatives, who will consider and report in conference with persons selected by the Treasury— ‘**T, Whether such an arrangement is in fact practicable. ‘TI. What is the amount and nature of the accommodation to be transferred. “TIT. What alterations or adaptations are necessary to render it in all respects suitable to the needs of the University, ““TV, Under what conditions it should be held from Her Majesty's Government by the Senate. “*The object of the Conference would be expressly limited to furnishing Her Majesty’s Government with fullinformation upon the several points indicated above; and the consent of the several parties to enter the Conference would not pledge them to accept any recommendation which the representatives, or a majority of them, may make. “*My Lords approve the course recommended by the First Lord and the Chancellor of the Exchequer.” The representatives of the Council of the Institute appointed to take part in this Conference were Lord James of Hereford, the Right Hon. Sir Henry Fowler, M.P., and Sir Frederick Abel. The Conference thus constituted held several meetings at the Treasury and at the Institute, and the Committee paid repeated visits to South Kensington with a view to ascertain the exact extent and capabilities of the building, particularly of that por- tion of it which it is proposed to assign to the University. On the first of these occasions the Prince of Wales inet the Committee and accompanied the members through the various rooms of the Institute. His Royal Highness evinced much interest in the proposed arrangement, and expressed a strong wish to meet the requirements of the Senate and to facilitate the work and due development of the University. At a subsequent meeting the representatives of the University were requested to draw up, for the information of their col- leagues, a statement showing the nature of the accommodation needed by the University, and also the way in which the eastern portion of the building might be adapted to the use and to the future requirements of the University. In conformity with this wish the Committee prepared a memorandum, which became the basis of discussion at subsequent meetings of the Conference. Among the points referred to in this document are the future requirements of the University. Upon this subject the repre- sentatives of the University remark : “In considering the proposal to exchange the present build- ing in Burlington Gardens for a portion of that now occupied by the Imperial Institute, it is necessary not only to take into account the means of supplying these serious deficiencies, but also to forecast the probable requirements of the University under its new constitution. The details of that constitution are now being settled by the Statutory Commission appointed under the provisions of the University of London Act of 1898. ““The new statutes will certainly provide for a large ex- tension in the work and usefulness of the University, will invest it with new teaching powers, will bring it into closer relations with the principal colleges and medical schools of the metropolis, and will, without encroaching on the ordinary functions of those institutions, probably do much to encourage the development of post-graduate study and of research, under the direction of the governing body of the University, and in its central building.” With regard to the central portion of the building, the memorandum states :-— “Tt is evident that joint user of this neutral territory, on the part of the Institute and the University, would be for many reasons inconvenient unless the relations and claims of the two bodies are clearly defined. Otherwise frequent references to the Treasury would become necessary. ‘* Moreover. it is essential for the credit and for the usefulness of the metropolitan University that it should not be regarded as, in any sense, a department of another institution. It would cause grave disappointment to the Senate and to the Graduates if we were unable to report to them that the Government were sensible of the importance of this consideration, and able to give effect to it. ‘*Tt is obviously desirable that the building to be known as the University of London should have a separate entrance.” 234 Tt was in relation to the neutral territory referred to that the representatives of the University felt it necessary to receive further explanations. It was at first proposed by the authorities of the Institute that a joint permanent Committee should be formed, and that while the University and the Institute respectively should be entitled to have the use of the central hall and the east conference hall on certain occasions to be specified beforehand, the occupation of the rooms on other occa- sions should be settled by arrangement with this Committee. But grave inconvenience and the possibility of future compli- cations were foreseen in such an arrangement. From the first it had been impressed upon the Treasury that the relations of the University should be with the Government alone, and that any plan which assumed that the University should be either tenants or partners with another institution would certainly be un- welcome to the Senate. The Committee therefore insisted that, in accordance with the letter of Sir Francis Mowatt of Christmas Day 1898, the University should be the tenants of the Govern- ment only. Asa result the following formal communication, dated May 16, was received by the Vice-Chancellor from Sir Francis Mowatt :-— “« With reference to our recent discussions as to the conditions on which the Government is prepared to offer to the University improved and enlarged accommodation in the Imperial Institute building, Iam authorised by the Chancellor of the Exchequer to inform you that the original intention of the Government re- mains unchanged, namely. to take over a// the present building for the use of (a) the University of London, and (4) the authorities of the Imperial Institute, and that he has caused notification to this effect to be communicated to the Council of the Institute. “*T am at the same time instructed to forward to you the en- closed memorandum indicating that the University will hold direct from the Government.” The memorandum enclosed was as follows :— “In any arrangement under which the University is invited to occupy a part of the Institute building, it will be an absolute condition that the University holds directly and solely from the Government and not in any form or degree from the Institute. «This is true equally of the part to be occupied exclusively by the University and of the part to be occupied alternately by the University and by the Institute under arrangements to be approved by the Treasury.” The exact nature of the arrangements here referred to between the University and the Treasury, with respect to the central portion of the building, the galleries, and the east conference hall, will be fixed from time to time on the understanding that the full and exclusive use of these portions of the building will be secured for the University at all times at which they are required for purposes of examination, for the annual ceremony of the presentation for degrees, and for the meetings of Con- vocation. The Senate will also afford, as it has been accustomed to do during many years, accommodation to meetings and con- gresses of a national and international character, as well as for assemblies of graduates or others interested in the promotion of collegiate or advanced education. Subject, therefore, to any reservation which the Treasury may make as to the use of the central portion of the main building for occasional meetings of the Imperial Institute, the building, with the exception of the west wing, will either belong exclu- sively to the University or will be at its disposal when required. The main entrance will be used by the University and by the Imperial Institute jointly. An additional University entrance and staircase will give access to the east wing, and will serve for candidates for examination and for other purposes. . The assent of the Council of the Imperial Institute to the Government proposals was notified in a letter dated June 5 from Lord James of Hereford to Sir Francis Mowatt. With regard to the future appropriation of land adjacent to the building, it is understood that, in view of the probable future requirements of the University, especially in the direction of scientific and literary research and of post-graduate lectures and studies, the University will be entitled to a first claim on any vacant ground which may hereafter prove to be needed. The area thus available is very large. It is understood that the Government is prepared to under- take the whole cost of the removal of the effects of the Uni- versity to its new quarters, and that the Chancellor of the Exchequer will include in the estimates for this year a sufficient NO. 1549, VOL. 60] NATURE [JuLy 6, 1899 sum to meet all charges for furnishing the rooms, for adapting them to the purposes of the University, and also for effecting such structural and other changes as may be found necessary in subsequent consultation between the officers of the University and the architect of the Board of Works. At present no change is proposed in the financial arrangement by which the charges of the University for the maintenance and care of the build- ing, the provision of stationery and stores, the salary of the officers, and the expenses of administration are borne by the Treasury, and are provided, so far as they exceed the amount received from candidates in the form of fees, by an annual vote in Parliament. F This arrangement is, however, wholly exceptional, and does not apply to any other University in Great Britain. It un- doubtedly relieves the authorities of the University from all” financial concern or responsibility. But it cannot be regarded as a permanently satisfactory settlement, or one which is likely to conduce to the repute and independence of the University, or to its due development in the future. It has the obvious and serious result of discouraging endowments and gifts, and of diminishing the interest which the inhabitants of London ought to take in their chief academic institutions. So long as the University is dependent for its maintenance on an annual vote in Parliament, it can hardly be expected to receive much voluntary support. Such generous gifts from private persons or from municipal bodies as have enriched the colleges of the Victoria University, and have recently been promised to the contemplated University of the Midlands, are not likely to be forthcoming in London while the University exists on its present financial basis. But it may well be hoped that under different conditions the University will evoke similar local patriotism to that which has been so conspicuously shown in Manchester, Liverpool, Leeds, Cardiff, Newcastle and Nottingham, and that the citizens of London will become conscious of a new responsibility, and will take a pride in strengthening and enlarging from time to time an institution which ought to serve as a great centre of intellectual life for the whole metropolis. The Government has throughout this negotiation shown a strong desire to make the best provision in its power to meet the needs of the University and the wishes of the Senate and the Graduates. And, having regard (1) to the fact that the present accommodation is insufficient, and that there are no means of enlarging it upon its present site; (2) to the size and dignity of the Institute building and its capacity for adaptation and expansion ; (3) to the fact that no alternative proposal for the housing of the University in a more appropriate place is likely to be made; and (4) to the consideration that the building, though not geographically central for London, is placed in the midst of a group of institutions— the Royal College of Science, the Natural History Museum, the City and Guilds of London Institute, the College of Music, and the Science and Art Galleries and Museums—which are all in various ways cognate in their objects with the purposes and work of the University, the Committee conclude by expressing the opinion that the proposal of the Government has been con- ceived in a fair and liberal spirit, and that it deserves the favour- able consideration of the Senate. PHYSICAL MEASUREMENTS IN ANTHROPOLOGY. THE question of the value of physical measurements is one that lies at the base of physical anthropology. Large numbers of often very extended series of measurements are con- tinually being published, new methods are constantly being proposed and tried ; but in spite of all this, it is questionable whether the value of the results obtained is proportionate to the trouble expended. Unfortunately there is variability in the methods employed, which may change according to the nationality of the investigators ; some methods are complicated like those of Benedikt and Tcersek, or, as in the case of the latter anthropologist, who takes 5000 measurements on a single skull, they may be impracticably numerous. Very precise measurement with refined instruments gives an apparent exacti- tude which appears to be more scientific than it really is. Preferable is the system that adopts a small number of measure- ments which can be readily made, and which have a better chance of being taken on a large number of subjects. The . le ee JuLy 6, 1899] aver te AE 235 extreme exactitude of cranial measurements, especially when based, for example, on the cephalic index only, has often led to creating imaginary races among a given people. These and other wholesome warnings are uttered by O. Hovorka Edler von Zderas in the Cetralblatt fiir Anthropologie, iii. p. 289, who also points out that there is no need to calculate indices to the first or second decimal, and he also states that in the analysis of a people one should not take account of differ- ences of Jess than ten units in the index. As all investigators are well aware, the cephalic index gives no information upon the real form of the skull; this has been well emphasised by Sergi, who has sought to establish a more rational system of skull nomenclature. M. L. Laloy supports (2 Anthropologie, x. p. 105) Hovorka’s general contention, and refers to the clever visual analysis of the inhabitants of Bretagne by Dr. P. Topinard, which was published in the Jowrnad of the Anthropological Institute (1897, xxviii. p. 99). In the last number of the Journal (new series, i. p. 329) Dr. Topinard gives the results of the trip which he made to Cornwall last year in order to compare the anthropological types there with those he had previously ascertained in Bretagne, But in our own country Dr. J. Beddoe has long adopted a similar method of investigation, and his acute and trained powers of observation have thrown a flood of light on the problems of the races of Britain. The methods of the doyex of British anthropologists are those of the field naturalist, and there are many who realise that what is generally knownas ‘‘ natural history,” is as integral a part of biology as is the most refined laboratory technique. It is well to use one’s eyes for other purposes than for reading off scales on instruments. “ WAVE OR BILLOW CLOUDS. A: SERIES of cloud photographs taken by Mr. Alfred J. Henry, of the United States Weather Bureau, and contributed to the Mlonthly leather Review for February, is on several grounds specially instructive. It is too frequently the case that photographers content themselves with a single plate of a cloudy sky, which specially re- commends itself to their notice by the grouping and arrangement of the vaporous patches. But in this instance we have a succession of pictures of the same clouds, showing their varia- tion during the interval, and, more- | atmosphere. | regular arrangement of streaks presents the peculiarity of cover- similar weather conditions gave rise to a similar formation of clouds (also photographed) some two months later. This is all that instrumental registration and careful observ- ation can teach us, and possibly the slow onward movement of meteorological science is traceable to the strict adherence we have generally shown to the record of instrumental indications, rather than a confident appeal to theoretical research. But the study of such a cloud formation as that pictured here goes a step beyond the reading of instruments, and places in our hands a powerful means by which to investigate the motion of the It cannot have escaped general notice that this ing a considerable extent of the sky, almost simultaneously. On a comparatively clear sky these strips of cloud are suddenly | formed; and on the other hand, a sky uniformly covered can, in a very short space of time, break up and offer the appearance of these billow waves. This sudden origin of parallel streaks finds a complete analogy in the formation of waves over still water, when a slight wind agitates the surface, and it is seen to break into ripples over a considerable area. Von Helmholtz, working on this suggestion, has shown conclusively that these billow waves are due to the existence of air strata of different temperatures moving with different velocities, and are produced at the surfaces of separation of these various strata. Travellers in balloons have confirmed this theory from actual experiment, and have shown that at very various altitudes this peculiar formation is encountered. It may be that the billow clouds are over, taken in various azimuths at different stations, so that we get the same formation viewed from different standpoints. We regret that we can only reproduce one of the very admirable pictures that Prof. Henry has secured, It is the first of the series, and shows the typical arrangement of these clouds as they first arrested the attention of the observer. The altitude was probably that of the mean altocumulus level. Occurring as these clouds do at all possible heights above the surface, we are glad to netice that the term wave or billow, following the nomenclature of Helmholtz, is coming into use, since such a description more nearly expresses the character of the formation than do other terms which generally refer to the height alone. We have here in the cause of the formation of these clouds an instance of the advantage of theoretical investigation over simple observation. The readings of meteorological instru- ments explain nothing of the origin or behaviour of atmospheric waves. Prof. Henry has recorded for us, with the care that becomes a meteorologist, that the wind was blowing steadily from the north-west with a velocity of twelve miles an hour. Rain had ceased shortly before, and the temperature, which had fallen to 34° during the night, had risen at the time at which the photograph was taken (Sh. 25m. a.m.) to 36°. The direction of the parallel bands when first observed was ap- proximately east and west. Later they took up a position about N. 80° W. to S. 80° E. In an hour and a half the typical appearance of the billow wave had passed away, leaving the sky about half-covered with cirrus and cirro stratus. It is hot unimportant to note, however, that the occurrence of NO. 1549, VOL. 60] Wave or Billow Clouds. visible to us only under peculiar circumstances of moisture, but the wave motion in the invisible air is probably a most common phenomenon, and one that plays a large part in determining our weather conditions. THE PROPOSED MAGNETIC SURVEY OF THE UNITED STATES} THE present superintendent of the Coast and Geodetic Survey, Prof. Henry S$. Pritchett, perceiving the need of expansion in the magnetic work of the Survey, has brought about the formation of a separate division, known as the Division of Terrestrial Magnetism of the United States Coast and Geodetic Survey. The chief of this division is to be Dr. L. A. Bauer, who will have full control of all magnetic work, both in the field and in the office. The following preliminary outline will serve to give some indication of the character and scope of the work it is proposed to carry out with the enlarged opportunities. SECULAR VARIATION INVESTIGATIONS. The best evidence of the great demand for secular variation data is the fact that, thus far, eight editions of Schott’s secular variation paper have been successively issued by the Survey. 1 Abridged from an advance proof of a paper. by Dr. L. A. Bauer in Terrestrial Magnetism. 236 NATURE [JuLy 6, 1899 In all matters relating to the re-location of land boundaries, where it is frequently necessary to know the precise amount of angular change in the direction of the magnetic meridian since the first or original survey, the Coast and Geodetic Survey is recognised throughout the country as the ultimate authority. The amount of money saved to landowners by such authorita- tive determinations as the Survey is able to furnish, can scarcely be estimated. It certainly exceeds many times the total amount to be spent for magnetic work. Every effort will be made in the future to multiply and verify the secular variation data, and requests for information on the part of surveyors will be encouraged in every possible manner and true meridian lines established for them. This involves the determination of the magnetic elements, declination, dip, and intensity at various points throughout the land. Exactly how close the stations shall be to each other depends upon the special purpose to be accomplished with the means at hand, and the magnetic character of the regions in- volved. A magnetic survey has peculiar difficulties to contend with ; for the quantities to be experimentally determined are for ever undergoing changes—some periodic, others not periodic. A magnetic survey must, therefore, be made to refer to some particular moment of time, and such means must be taken as to enable one to reduce all the measurements, not only to the selected epoch of the survey, but also, as occasion may demand, to some other epoch in the near past or in the near future. Means must also be taken for the proper elimination of all such errors as are to be referred entirely to the particular magnetic instrument used, z.e. instrumental errors. NUMBER AND DISTRIBUTION OF STATIONS. At how many stations it will be necessary to determine the magnetic elements? The areas of the countries at present be- longing to the United States are, approximately, as follows :— United States 3,025,600 square miles Alaska een 5773390 a0 Hawaiian Islands ... 6,250 oe Porto Rico 35530 3 Total 3,612,770 Op Hence the area is equal to that of entire Europe, or about one-fifteenth of the entire land area of the globe. As magnetic surveys have been especially prosecuted in Europe, it will be of interest to note the density of distribution of the magnetic stations in two recent, fruitful magnetic surveys—viz. that of Great Britain, where there was one station to every 139 square miles ; and that of Holland, embracing one station to every 40 square miles. Suppose one station is decided upon, on the average, to every 100 square miles—an end that may be obtained some day—then the determination of the magnetic elements would be required at 30,000 stations within the United States. At the rate of 400 stations a year, the magnetic survey, as detailed as this, would require for its completion at least seventy-five years. It is not well, however, to have a magnetic survey extend over such a long interval of years. The errors incurred in reducing the observations to a common epoch would greatly exceed the errors of observation. It is evident, then, that a very large number of observers and instruments would be required to complete the survey within a short interval, say ten years at the most, or a less detailed survey will have to be undertaken. The plan of conducting a magnetic survey of the United States which appears to be best suited to the present conditions, and one that it is possible to carry out within a reasonably short time, is as follows :—To make first a general magnetic survey of the country with stations about twenty-five to thirty miles apart ; then, as opportunities present themselves, to add stations in the magnetically disturbed areas. The observations at the ‘‘ repeat stations,” made from time to time, will furnish the proper secular variation corrections. The great advantages of this plan over that of attempting a greatly detailed magnetic survey at once, the steady progress of which over the entire country, on account of its extent, would necessarily be very slow, will be readily perceived. It will be of interest, however, to point out that the plan, as briefly out- lined, will make it possible, within a reasonable time, to con- NO. 1549, VOL. 60] struct two sets of magnetic maps for the same epoch, each set based upon a different distribution of the stations. An oppor- tunity will thus be afforded, as in the case of the magnetic survey of Great Britain, to obtain some idea of the accuracy with which the isomagnetic lines can be determined. The satis- factory solution of this question will serve as a valuable guide in future magnetic work. Various State geologists, incited by the example set by the State Geologist of Maryland, Prof. William Bullock Clark, either have already made plans, or are making plans, for detailed magnetic surveys of their respective States, in co-operation with the Coast and Geodetic Survey. MAGNETIC SURVEY OF OCEAN AREAS. Provision for the determination of the magnetic elements at sea are being made. With the many vessels at the service of the Coast and Geodetic Survey, exceptional facilities for this purpose will be afforded. In fact, one of the chief duties of the Survey is the supplying of magnetic data to the mariner. From an economic standpoint this feature of magnetic work is the one really of the greatest practical importance. In recognition of this fact, the Survey vessels will hereafter take advantage of every opportunity to obtain the magnetic elements on sea and on shore. MAGNETIC OBSERVATORIES. The rapid, successful, and economical execution of the plans as above briefly outlined requires the establishment, at certain points, of magnetic observatories, where the countless variations in the earth’s magnetic force are continuously and automat- ically recorded, enabling thus the proper corrections to be applied to observations made at stations at any hour of the day. The present plans contemplate the establishment of a mag- netic observatory near Washington City—this will be the Central or Standard Observatory; another near Seattle, State of Washington; one in the Hawaiian Islands, and one in Alaska. With the co-operation of the observatories at Toronto, Mexico and Havana, and with the aid of secondary or temporary observatories established as occasion may demand, the areas to be surveyed will be fairly well covered. It is very much to be hoped, however, that the universities and colleges in the United States will seriously consider the establishment of magnetic observatories. Many an institution which lacks the means of making a reputation in astronomical work, could still afford to inaugurate useful work in terrestrial magnetism. The United States stands at the bottom of the list of civilised countries possessing magnetic observatories. Almost every European Power of note maintains, not only one, but several permanent magnetic observatories. France has four already established, and four additional ones in process of erection ; and progressive Japan, with its small strip of territory, has six continuously operating magnetic observatories. The recent International Magnetic Conference recommended the establishment of a magnetic observatory at the Lick Ob- servatory. It is earnestly to be hoped that this suggestion will be carried out. It is unfortunate that the San Antonio ob- servatory in Texas had to be abandoned. A permanent observatory should be re-established in this locality. The scheme of work for the Coast and Geodetic Survey observatories will embrace, in addition to the regular magnetic work, observations in atmospheric electricity and of the electric currents within the earth. Such observations can be carried on with practically no additional cost, and yet add greatly to the value of the observatory work. Arrangements will likewise be entered into with the Potsdam Magnetic Observatory for the making of strictly simultaneous observations of a special character. The plan of referring the initiation and prosecution magnetic work in America to such a well-organised department as the Coast and Geodetic Survey, the work of which is recognised universally as of the highest order, will readily be seen to have decided advantages. In the first place, the machinery for carrying on the work is already to a great extent inexistence. The observer engaged in geodetic or astronomical work can frequently include to advantage magnetic observations, and thus can often be saved the chief cost of magnetic work— the occupying of stations. Again, the care and refinement with which the geodetic and astronomical work of this bureau is carried out will ever be an incentive to keep the magnetic work of the same high order. Juty 6, 1899] NATURE 237/ UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Oxrorp.—The following is an extract from the speech de- livered at the Encaenia on the presentation of F. D. Godman, F.R.S., Trustee of the British Museum, for the degree of D.C.L., June 21. “‘In ea Naturae parte quae ad animalium herbarumque varietates pernoscendas spectat neminem vel diligentius vel utilius hoc viro laborasse scitote. Ille enim, scientiae amore instigatus, Americae quae dicitur centralis saltus silvasque una cum amico suo caro Osberto Salwino (nuper fato eheu! nobis abrepto) longis pererravit peregrinationibus atque fruges fetusque omnes ejus orbis ter- rarum partis adcurate investigavit. : Nec illud tacendum arbitror eundem diversi generis species illic ab ipso cura infinita collectas quum rarissimas tum etiam pretiosissimas singulari munificentia Museo nostro Britannico donasse.” THE Committee of the City and Guilds of London Institute are inviting applications for the appointment of Assistant Professor in the Department of Civil and Mechanical Engineer- ing at the Institute’s Central Technical College. Particulars of the appointment may be had of the Honorary Secretary of the Institute, Gresham College, E.C. THE Board of Education Bill was considered by the House of Commons Committee of Ways and Means on Tuesday. It was resolved ‘* That it is expedient to authorise the payment, out of moneys to be provided by Parliament, of a salary, not exceed- ing 2000/., to the president of the Board of Education, and of salaries and remuneration to the secretaries, officers, and servants of the Board, in pursuance of any Act of the present Session to provide for the establishment of a Board of Education for England and Wales.” Major-GENERAL SIR JOHN F. D. DONNELLY, K.C.B., retired on Monday from the Secretaryship of the Science and Art Department, after forty years in the public service. In consequence of Sir J. Donnelly’s retirement, the Duke of Devonshire, Lord President of the Council, has made the following appointments :—Sir George W. Kekewich, K.C.B., the present Secretary of the Education Department, to be also Secretary of the Science and Art Department. Captain W. de W. Abney, C.B., to be the Principal Assistant Secretary of the Science and Art Department. Mr. W Tucker, C.B., to be the Principal Assistant Secretary of the Education Department. THE Duke and Duchess of York visited Exeter on Tuesday and opened a new wing of the Albert Memorial Museum and College. The Museum became affiliated with the Cambridge University several years ago, when the Exeter Technical and University Extension College was started, with Mr. A. W. Clayden as principal. This institution, to be known in future as the Royal Albert Memorial Museum and College, is now sufficiently equipped for the requirements of a local college. In opening the new wing, the Duke of York remarked that the efficient results attained at Exeter and also at Reading seem to indicate that it is possible for the municipal authorities of towns of moderate size to establish, with the co-operation of the great universities, institutions providing for higher and technical Instruction. The co-operation of the universities, with their expert knowledge, and the local authorities with their control of funds for educational purposes and their practical know- ledge of local needs, cannot fail to be of the greatest advantage to the community from an educational standpoint. SCIENTIFIC SERIALS, Meteorologische Zeitschrift, June.—On the amount of cloud in Europe during cyclonic and anticyclonic days, by Dr. C. Kassner. In this important discussion the author has invest- igated the cloud observations at five principal stations in Europe for twenty years (1871-90), and has followed a plan adopted by Dr. Leyst in another discussion by selecting the days in each month when the readings of the barometer were lowest or highest. These days, including the days preceding and following that on which the extreme reading occurred, are those called respectively cyclonic or anticyclonic periods. He finds that in NO. 1549, VOL. 60] cyclonic periods the maximum amount of cloud only occurs on the principal day in summer and autumn, while in winter and spring a large amount of cloud occurs in the evening of the preceding day as well ason the morning of the principal day. The preceding day has generally somewhat less cloud than the principal day, and almost always more than the following day. This result agrees with that deduced by the late Mr. Ley, and by the Deutsche Seewarte with respect to the distribution of cloud in cyclones. In anticyclonic periods the least cloud fre- quently occurs, not on the principal day, but on the preceding or following day ; this is especially the case at Christiania and Pavlovsk, where the least cloud occurs before the passage of the highest barometric pressure, and then gradually increases. Generally speaking, however, the principal day is clearest, and next to this the preceding day, but not always, for at Buda- Pesth and Tiflis the day following that of the maximum barometric pressure has less cloud than the day preceding. Bollettino della Socteta Sismologica Italiana, vol. iv., 1898, No. 9.—Old seismic instruments, by P. Tacchini, referring to an old form of the Cecchi seismograph and to Cacciatore’s mercury seismoscope, recently acquired by the Central Office of Meteorology and Geodynamics at Rome, and which, with others already in the possession of the office, will form the nucleus of a seismometrical museum.—Principal eruptive pheno- mena in Sicily and the adjacent islands during the half-year July to December 1898, by S. Arcidiacono.—Later modifica- tions in the electrical seismoscope of double effect, by G. Agamennone. Describes several improvements by which the instrument may be put more rapidly in working order.— Notices of earthquakes recorded in Italy (December 25 to 31, 1897), by G. Agamennone, the most important being an after- shock of the Umbria-Marches earthquake of December 27, and the Haiti earthquake of December 29. SOCIETIES AND ACADEMIES. LONDON. Royal Society, June 15.—‘‘ The Colour Sensations im Terms of Luminosity.” By Captain W. de W. Abney, C.B., DiG-L.,, PaRSs: This paper deals with a determination of the colour sens- ations (based on the Young theory) by measuring the luminosity of the three different colour components in a mixed light which matches white. At the red end of the spectrum there is but one colour extending from its extreme limit to near C, and there is no mixture of other colours which will match it, however selected, and is, on the theory adopted, a colour which excites but one sensation. At the violet end of the spectrum, from the extreme violet to near G, the same homo- geneity of light exists, but it is apparently due to the stimu- lation of two sensations, a red and a blue sensation, the latter never being stimulated alone by any spectrum colour. Having. ascertained this, it remained to find that place in the spec- trum where the blue sensation was to be found unmixed with any other sensation except white. By trial it was found that close to the blue lithium line this was the case, and that a mix- ture of this colour and pure red sensation gave the violet of the spectrum when the latter was mixed with a certain quantity of white. The red and the blue sensation being located, it re- mained to find the green sensation. The complementary colour to the red in the spectrum gave a position in which the green and blue sensations were present in the right proportions to make white, and a point nearer the red gave a point in which the red and blue sensations were present in such proportions as found in white, but there was an excess of green sensation. By preliminary trials this point was found. The position in the spectrum where the yellow colour complementary to the violet was also found. The colour of bichromate of potash was matched by using a pure red and the last-named green. To make the match, white had to be added to the bichromate colour. A certain small percentage of white was found to exist in the light transmitted through a bichromate solution with which the match was made, and this percentage and the added white being deducted from the green used, gave the luminosity of the pure green sensation existing in the spectrum colour which matched the bichromate. Knowing the percentage com- position in luminosity of the two sensations at this point, the luminosity of the three sensations in white was determined by 238 matching the bichromate colour with the yellow (complementary to the violet) and the pure red colour sensation. From this equation and from the sensation equation of the bichromate colour already found, the sensation composition of the yellow was determined. By matching white with a mixture of the yellow and the violet, the sensation equation to white was deter- mined. The other colours of the spectrum were then used in forming white, and from their luminosity equations their per- centage composition in sensations were calculated. The per- centage curves are shown. The results so obtained were applied to various spectrum luminosity curves, and the sensation curves obtained. The areas of these curves were found, and the ordinates of the green and violet curves increased, so that both their areas were respectively equal tothat of the red. This gave three new curves in which the sensations to form white were shown by equal ordinates. A comparison of the points in the spectrum where the curves cut one another, and of those found by the red and green blind as matching white, show that the two sets are identical, as they should be. The curves of Koenig, drawn on the same sup- position, are mentioned, and the difference between his and the new determination pointed out. The red below the red lithium line, as already pointed out, excites but one (the red) sensation, whilst the green sensation is felt in greatest purity at A 5140, and the blue at A 4580, as at these points they are mixed only with the sensation of white, the white being of that whiteness which is seen outside the colour fields. “A Comparison of Platinum and Gas Thermometers, including a Determination of the Boiling Point of Sulphur on the Nitrogen Scale: an Account of Experiments made in the Laboratory of the Bureau International des Poids et Mesures, at Sevres.” By Drs. J. A. Harker and P. Chappuis. Communicated by the Kew Observatory Committee. The present paper is the outcome of the co-operation of the Kew Observatory Committee and the authorities of the Inter- national Bureau of Weights and Measures at Sevres, for the purpose of carrying out a comparison of some platinum thermo- meters with the recognised international standards. A new resistance-box, designed for the work, and special platinum thermometers together with the other accessories needed were constructed for the Kew Committee, and, after their working had been tested at Kew, were set up at the laboratory at Sévres in August 1897. The comparisons ex- ecuted between these instruments and the standards of the Bureau may be divided into several groups. The first group of experiments covers the range —23° to 80°, and consists of direct comparisons between each platinum thermometer and the primary mercury standards of the Bureau. Above 80° the mercury thermometers were replaced by a gas-thermometer, constructed for measurements up to high temperatures. The comparisons between 80° and 200° were made in a vertical bath of stirred oil, heated by different liquids boiling under varying pressures. For work above 200° a bath of mixed nitrates of potash and soda was substituted for the oil tank. In this bath comparisons of the two principal platinum thermometers with the gas-thermometer were made up to 460°; and with a third thermometer, which was provided with a porcelain tube, we were able to go up to 590°. Comparisons of the platinum and gas-scales were carried out at over 150 different points, each comparison consisting of either ten or twenty readings of the different instruments. By the intermediary of the platinum thermometers a determin- ation of the boiling point of sulphur on the nitrogen scale was also made. The mean of three very concordant sets of determin- ations with the different thermometers gave 445°°27 as the boiling point on the scale of the constant volume nitrogen ther- mometer, a value differing only about 0°*7 from that found by Callendar and Griffiths for the same temperature expressed on the constant pressure air scale. If for the reduction of the platinum temperatures in our com- parisons we adopt the parabolic formula proposed by Callendar, and the value of 6 obtained by assuming our new number for the sulphur-point, we find that below 100° the differences between the observed values on the nitrogen scale and those deduced from the platinum thermometer are exceedingly small, and that even at the highest temperatures the differences only amount toa few tenths of a degree, Full details as to the instruments employed and the methods adopted are given in the paper, NO. 1549, VOL. 60] NATURE [JuLy 6, 1899 “On the Comparative Efficieny as Condensation Nuclei of positively and negatively charged Ions.” By C. T. R. Wilson, M.A. Communicated by the Meteorological Council. When moist air is ionised, a greater degree of supersaturation is required to cause water to condense on the positively charged ions than on the negatively charged ones. The experiments consisted in measurements of the expansion required to cause condensation in the form of drops in air initially saturated and con- taining ions alternately nearly all positive and nearly all negative The ratio of the final to the initial volume being indicated by Zo/%,, then to cause water to condense on negatively charged ions, the supersaturation must reach the limit corresponding to the expansion 7,/7;=1°25 (approximately a fourfold super- saturation). To make water condense on positively charged ions, the supersaturation must reach the much higher limit cor- responding to the expansion v)/v,=1°31 (the supersaturation being then nearly sixfold). Thus, if ions ever act on condens- ation nuclei in the atmosphere, it must be mainly or solely the negative ones which do so, and thus a preponderance of negative electricity will be carried down by precipitation to the earth’s surface. Experiments were carried out which appear to prove that the difference in the condensing power of positive and negative ions is not to be explained by supposing the charge of each negative ion to be, for example, twice as great as that of each positive ion. Experiments were also tried to test whether the rainlike condensation, which always takes place in moist air when the expansion 7/v=1'25 is exceeded, is due to slight ionisation of the moist air. These experiments led to the con- clusion that this is not a case of condensation on ions ; unless the process of producing the supersaturation itself gives rise to ionisation. i Mineralogical Society, June 20.—Prof. A. H. Church, F.R.S., President, in the chair.—Mr. E. G. J. Hartley gave the results of analyses of so-called plumbogummite from Roughten Gill, Georgia, and Huelgoat. The blue mineral from Roughten Gill, usually regarded as a silicate or carbonate of zinc, proved to be identical with the hitchcockite from Georgia. Both minerals have been analysed by Mr. Hartley, and shown to contain about 19 per cent. of water and 3 percent. of carbonic acid. In a note on the optical characters, Prof. Miers finds that these two minerals present absolutely the same appearance under the micro- scope, and differ somewhat from the only other known hydrated lead aluminium phosphate, viz. the plumbogummite from Huelgoat in Brittany. Mr. Hartley’s analyses of this mineral differ from those of Damour, and shows that it has by no means the same composition as hitchcockite, and it is therefore considered to be a distinct species. —Mr. H. L. Bowman gave a detailed description of the optical crystallographic and chemical characters of a clear green rhombic pyroxene from the diamond- washings of South Africa.—Messrs. G. T. Prior and L. J. Spencer contributed a paper on the chemical composition of tetrahedrite. In a previous investigation proving the specific identity of the rare mineral binnite with tennantite, the numbers obtained in the analysis, like those of several older analyses of tennantite, agreed much more closely with the formula 3Cu,S.As,S3 than with the ordinary text-book formula 4Cu,S.As,S3, originally proposed by Rose. In the present communication the authors describe the physical and chemical characters of three specimens of tetrahedrite. The result of the analyses made by Mr. Prior is to confirm the idea that the true formula for tetrahedrite proper is 3Cu,S.Sb,S3, and also to show that when iron and zinc are present they enter into the composition of the crystals not as 3(Fe,Zn)S.Sb,S3, but as 6(Fe,Zn)S.Sb,S3, in which 6(Fe,Zn)S isomorphously replaces 3Cu,S. The proposed general formula for fahlerz (tetrahedrite and tennantite) is accordingly 3R'gS. RS, + #[6R’S.R'.S5] where R’ = Cu, Ag; R’” = Sb, As, Bi; R” = Fe,Zn, and x is generally a small fraction, rising, however, to 4 in the case of the highly ferriferous tetrahedrite ‘‘ coppite.”—Mr. L. Fletcher described the chemical analysis of a constituent of the meteoric iron of Youndegin, Western Australia, and gave an account of the fall of meteoric stones at Mount Zomba, British Central Africa, on January 25, 1899.—Mr. Herbert Smith pointed out the specific identity of the new oxychloride of lead para- laurionite, described by him in April 1898, with the new mineral rafaélite, a description of which by the late Dr. Arzruni has just been published. a ‘ r JuLy 6, 1899] NATURE 239 Geological Society, June 21.—W. Whitaker, F.R.S., President, in the chair.—On a series of agglomerates, ashes, and tuffs in the Carboniferous Limestone series of Congleton Edge, by Walcot Gibson and Dr. Wheelton Hind. With an appendix on the petrography of the igneous rocks, by H. H. Arnold-Bemrose. After referring to the discovery of volcanic rocks in the upper part of the Carboniferous Limestone series at Tissington, the authors proceed to describe evidence of vol- canic action of the same age on the western slopes of Congleton Edge.—On some ironstone fossil nodules of the Lias, by E. A. Walford.—Additional notes on the glacial phenomena of Spits- bergen, by E. J. Garwood. This paper contains the results of additional observations on the ice of Spitsbergen made by the writer in 1897. The inland ice visited occupies two distinct areas, separated by Dickson’s Bay and Wijde Bay. The radiating point lies somewhat north-west of the centres of each area, with supplementary radiating points on the north and east. The group of peaks including the Three Crowns may be regarded as nunatakkr. The valley-bound ground-ice does not necessarily travel in the same direction as that of the sur- face. The effect of nunatakkr on the surface of the ice-sheet was studied, and from this it was often found possible to infer the existence and position of buried mountain-ridges. On the stoss-sette of a nunatak moraine-material is often discharged. The movement of the ice has frequently converted the ice- bridges across crevasses into arches and tunnels, some of which carry part of the drainage of the ice-sheet. Portions of old stranded ground-moraines, formed when the ice was more ex- tensive, were sometimes found to have fallen upon the lowered ice-Sheet, and to be mingled with modern moraine-material. Englacial and superficial rivers are described, and one of the latter was found to be depositing gravelly material along a line at right angles to the valley down which the ice was flowing. Certain observations on the rate of movement of the ice-sheet seem to indicate that this is not less than fifteen to twenty feet in twenty-four hours; while the glaciers near the sea-margin appear to be travelling about twenty-five feet in the same time. The action of sea-ice is described, and it is inferred that a certain amount of rounding and scratching of shore-rocks, and possibly part of the smoothing of boulders, may be due to this agent.—Additional notes on the vertebrate fauna of the rock- fissure at Ightham (Kent), by E. T. Newton, F.R.S. Royal Microscopical Society, June 21.—Mr. E. M. Nelson, President, in the chair.—The President exhibited an old 4-inch objective made by Andrew Ross, which had been presented to the Society by the Master of the Rolls. It was a rare form of objective, constructed probably about the year 1838, and possessed a very primitive form of adjustment. A special interest was attached to it because it formerly belonged to the father of the donor, Prof. John Lindley, the second President of the Society (1842-43).—The President also ex- hibited a new coarse adjustment which Messrs. Watson had made in accordance with a suggestion contained in his paper read before the Society in March last. It showed that with a loose pinion it was possible to have a rack coarse adjustment that would work without ‘‘loss of time.”—A paper by Mr. Jas. Yate Johnson, entitled ‘* Notes on some sponges belonging to the Clionidz obtained at Madeira,” was taken as read. Six slides of Spiculz, &c., in illustration of the paper, were exhibited under microscopes.—The President called the attention of the Fellows present to an exhibition by Mr. Beck of parts of various wild flowers shown with low powers.—This was the last meeting of the session, and the President announced that the first meeting after the vacation would be on October 18. EDINBURGH. Royal Society, June 5.—Sir Arthur Mitchell in the chair.— A note by Dr. Thomas Muir, on a persymmetric eliminant, was taken as read.—Dr, A. T. Masterman read a paper on contri- butions to the life-histories of the cod and the whiting. The paper was illustrated by numerous diagrams tracing the succes- sive stages of development from lengths of 3 mm. to lengths of 25mm. There was found to be a greater abundance of pigment in young whiting, and the body shows a characteristic pigmented lateral line. The migration of the young of each species shore- wards was also studied. In the case of the cod the transition was very marked from surface to mid-water, and thence to the littoral region. Thus the limiting length of surface forms was 17 mm., of mid-water forms a little over 25 mm., and later NO. 1549, VOL. 60] forms were all found in the littoral regions. No attempt has as yet been made to trace outward migration, if there be any. As had already been pointed out by Prof. M°Intosh, the migration of the whiting was much more indefinite. Sufficient causes for these migrations had not yet been satisfactorily made out.—Dr. Hugh Marshall gave a preliminary note on the hydrolysis of thallic sulphate. June 19.—Sir William Turner, F.R.S., in the chair.—A paper by Dr. Thomas Muir, on the eliminant of a set of general ternary quadrics, was taken as read.— Messrs. A. C. Seward, F.R.S., and A. W. Hill presented a paper on the structure and affinities of a Lepidodendron stem from the Calciferous Sandstone of Dalmeny. The fossil stem described in this paper was found by Mr. J. Kerr, of Edinburgh, and generously handed over by Mr. Robert Kidston, of Stirling, to Mr. Seward for examination and description. The peripheral portion of the stem is occupied by a band of secondary cortical tissue (phelloderm) about 5-7 cm. in breadth ; the more internal cortex has not been preserved, but the central cylinder is un- usually perfect. The specimen measures 33 cm. in diameter. A fairly broad pith occupies the centre of the stem, and this is enclosed by a ring of primary xylem succeeded by a broad band of secondary xylem. The leaf traces exhibit a well-marked secondary growth; each consists of a few primary tracheids, accompanied bya fan-shaped group of short and thin-walled tracheal elements. The stem appears to be identical with Lepidophloios Wunschianus from Arran, and a comparison is also instituted with Lefidophloios Harcourté?, a species characterised by the absence or late development of secondary wood.—Dr. T. H. Bryce read a paper on duplicitas anterior in an early chick embryo. This very rare condition in birds was examined in careful detail, and the structure of the duplex embryo was demonstrated by microphotographs of typical section.—In a paper on the trap-dykes of the Orkneys, Mr. J. S. Flett gave a description of a series of trap-dykes running mostly in an east-north-east direction, and cutting the Old Red Sandstone of Orkney. They are principally camp- tonites, but include also bostonites, monchiquites, fourchites, alnoites, and mellilite monchiquites. They are remarkably fresh, and show an interesting series of gradations between the different types. They are probably of Tertiary age, and have all proceeded from one focus. The presence of a single diabase dyke points to their origin from a gabbro magma.—Miss E. Chick presented a paper on the vascular system of the hypocotyl and embryo of Ricénus communis, which contained a detailed study of the behaviour of the vascular system in its passage from the root to the stem. Certain anomalies which have been observed were explained, and the inquiry brought out very clearly the individuality of the bundles as compared with the whole central cylinder of the root to which they belong.— Dr. W. Peddie, ina note on Mr, J. O. Thompson’s paper on torsional oscillations (see NATURE, May 25, p. 86), pointed out that Mr. Thompson’s suggested explanation of the results de- scribed by Lord Kelvin is very improbable, for there is no apparent reason why too large an initial oscillation should be given always to the fatigued wire and not to the unfatigued wire. Experiments on an iron wire, already described by Dr. Peddie, showed distinct fatigue of elasticity. It was also pointed out that Mr. Thompson’s own results seem themselves to indicate fatigue. PARIS, Academy of Sciences, June 26.—M. Van Tieghem in the chair.—Note accompanying the presentation of the fourth part of the photographic atlas of the moon, by MM. Loewy and Puiseux. The salient characters of the regions represented are described. — Preparation of fluorine, by electrolysis, in an apparatus of copper, by M. Henri Moissan. The costly plati- num apparatus hitherto employed in the preparation of fluorine may, it is found, be replaced by one of copper, which is less attacked than most other metals. It is probable that the copper becomes coated with a thin layer of copper fluoride which, being insoluble in hydrofluoric acid, prevents further action taking place.—Action of some gases on caoutchouc, by M. D’Arsonval. At pressures varying from 1 to 5 atmospheres caoutchouc absorbs large quantities of carbonic anhydride and, at the same time, increases considerably in volume and becomes more gelat- inous and less elastic. On exposure to air the gas is gradually lost, and the substance resumes its original properties. In virtue of this property, vessels of caoutchouc readily allow car- 240 NATORE [JuLy 6, 1899 bonic anhydride to pass through their walls. The action is much slower in the case of oxygen and is very slight with nitrogen. —The report of the commission recommending the revision of the map of France was adopted.—Observations on the work of MM. S. Lie and A. Meyer. A mathematical paper.—A new formula relating to quadratic residues, by M. P. Pépin. A paper dealing with the theory of numbers.—On the equation of motion of automobiles, by M. A. Petot. A reply to the criticisms of M. Blondel on a former communication by the author.—On the temperature of maximum density of aqueous solutions of alkali chlorides, by M. L. C. De Coppet. Experiments were made with the chlorides of potassium, sodium, lithium, and rubidium. Itis remarkable that the mole- cular lowering of the point of maximum density caused by lithium chloride is less than half that observed in the case of the other salts examined.—On an oscillation phakometer, by M. Ch. Déve. The superior accuracy claimed for this instrument for measuring the curvature of optical surfaces, &c., depends on the use of a novel artifice for determining the exact position of an image.— On a laboratory spectroscope in which the dispersion and the scale are adjustable, by M. A. De Gramont.—On the polar- isation of dielectrics, by M. Liénard. Observations on a pre- vious note by M. Pellat on this subject.—Results of seismic observations in Greece from 1893 to 1898, by M. D. Eginitis. During the six years over which the observations extended 3187 disturbances were recorded, the average annual number being 531 and the maximum 876 (in 1893). Seismic disturbances are more frequent in the night than in the day, and, as regards their annual distribution, exhibit a maximum in spring and a minimum in autumn.—On the constitution of the oxides of rare metals, by MM. G. Wyrouboff and A. Verneuil. Considera- tions relative to the formation of various complex salts of cerium and thorium lead to the suggestion that the oxides of these metals have the formula (CeO), and (ThO), respectively, in which one of the CeO or ThO groups differs in function from the rest.—The action of ferric chloride and bromide on some aromatic hydrocarbons and on their halogen substitution de- rivatives, by M. V. Thomas. A continuation of previous work on the subject. From the product of the action of ferric chlor- ide on paradibromobenzene the author has succeeded in iso- lating two new bromotrichlorobenzenes which melt at 93° and 138° respectively.—The preparation of phenylic chlorocarbon- ates, by MM. Et. Barral and Albert Morel. The action of a solution of carbonyl chloride in toluene on an aqueous solution of the sodium compound of phenols is shown to afford a ready means of preparing a number of aromatic chlorocarbonates. The temperature at which the reaction takes place should not exceed 40-50", otherwise decomposition ensues, and the sym- ‘metrical phenylic carbonate is produced.—On cerine and fried- eline, by MM. C. Istrati and A. Ostrogovich. By fractional: dissolution in, and crystallisation from, chloroform, the sub- stance formerly described by one of the authors as ex- tracted from cork has been separated into two distinct compounds, cerine, Cy,H4,O0,, and friedeline, C,,H-=)O..—On some new reactions of indolic bases and albuminoid compounds, by M. Julius Gnezda. When indol and its derivatives are heated with excess of oxalic acid,a fine purple coloration is developed, and a similar reaction is given by albumen, peptones, and gelatin. Some other dibasic acids may be used instead of oxalic acid. Other colour reactions brought about by hydro- fluoric acid and hydrofluosilicic acid are also described. —Pre- liminary tests for the presence of rare metals in mineral waters, by M. F. Garrigou. In the author’s opinion, the presence of rare metals of the copper and tin groups in mineral waters is “more frequent than is generally supposed.—On the formation of pearls in Meleagrina margaritifera, by M. Léon Dignet. Genuine pearls are not simple deposits of nacreous material accidentally produced by glandular secretions, but are the result of a definite physiological action having for its aim the elimin- ation of parasites or other causes of irritation.—On the embry- ogeny of Protzla metlhact, by M. Albert Soulier.—Regeneration of members in J/antedes and the constant production of a tetramerous tarsus in members regenerated after autotomy in pentamerous Orthoptera, by M. Edmond Bordage.—On the histology of the digestive tube in the larva of Chzronomus plumosus, by M. P. Vignon.—Contribution to the study of Actinidia (Dillentaceae), by M. Florentin Dunac.—On the experimental production of fascicular stems and inflorescences, by M. L. Géneau de Lamarliere.—Velocity of propagation of nervous oscillations produced by unipolar excitation, by M. NO. 1549, VOL. 60] Auguste Charpentier.—General and local anesthesia of motor nerves, by Mlles. I. Ioteyko and M. Stefanowska.—Physio- logical significance of alcohol in the vegetable kingdom, by M. P. Mazé.—On the action of currents of high frequency in arthritis, by M. Apostoli.—On the influence of electrolytic action in the production of radiographic erythema, by MM. H. Bordier and Salvador.—Further demonstrations of the variations in the amount of iron present in the tissues under the influence of pregnancy, by M. A. Charrin. GOTTINGEN. Royal Society of Sciences.—The Wachrichten (physico- mathematical series), part i. for 1899, contains the following memoirs communicated to the Society :— January 14.—W. Voigt: On the inflexion of plane non- homogeneous waves at the straight edge of an infinite absolutely black screen.—E. Riecke : On the work expended in producing large sparks with a Topler induction-machine.—H. Liebmann : A new property of the sphere.—O. Miigge : On new structural faces in the crystals of unalloyed metals. February 11.—H. Minkowski: A criterion for algebraic numbers. February 25.—C. Runge: On the solution of certain equa- tions with integral coefficients. —R. von Zeynek: On the irritability of sensory nerve-endings by variable currents.—W. Nernst : On the theory of electrical stimulation. —F. Nachtikal : On the proportionality between piezoelectric phenomena and the stresses that produce them. CONTENTS. PAGE Mammalian Distribution. By R.L. ....... 217 Antiquities from Benin, By H. Ling Roth... . 219 The Lost Volume of Hutton’s Theory of the Barth. By) ProfelaGeBonney, FR. Siete. ere2co Our Book Shelf :— Muybridge : ‘* Animals in Motion.”—F. J. J.-S. . . 220 Walters: ‘*Sanatoria for Consumptives in Various Parts ofthenWovldigeeememne =. | cere 221 Edser : ‘‘ Measurementand Weighing” ... . . 221 Grunmach : ‘‘ Die Physikalischen Erscheinungen und Kiraifte pes F7 en eee emeememacenss es > jn Grace: ‘‘ Practical Plane and Solid Geometry (Test Papers) sic seh emcee =) -/) > ae ee Heyne and Rosal : ‘‘ Practical Dictionary of Electrical Engineering and Chemistry in German, English and SpanishiayepeemewneneeNis) fie) > © - /<)velieeninam mmeea Letters to the Editor :— Magnetic Strain in Bismuth.—Shelford Bidwell, FURS.) DreGaGieknott <.. . | ee eee Gooseberry Saw-fly.— Prof. L. C. Miall, F.R.S. . 222 School Laboratory Plans.—A. E. Munby . 222 Illustrations of Mimicry and Common Warning Colours in Butterflies. (///ustrated.) By E. B.P. 222 The United States National Museum. (J///ustrated.) 225 An Improved Liquid Interrupter for Induction Coils. (Z/ustrated.\ By A. A. Campbell Swinton 226 The Seventh International Geographical Congress 227 Science at the Women’s International Congress . 228 Notes PMS ho 3 ao 228 Our Astronomical Column :— Gomet 1899\a(Swift) meee) i; -: +. =) XoueennpnmenmimmcnaTa Tempel’s Comet 1899 ¢ (1873 1I.). ....... = 232 Holmes’ Comet(r8o2s0Mi)ies. - we 232 Maxima of Mirae seen OG 232 The New Algol Variable in Cygnus - nes 2 The Housing of the Offices of the University of London . 0} Semen)... eee Physical Measurements in Anthropology . 234 Wave or Billow Clouds. (JZ/lustvated.) . 3 ties 235 The Proposed Magnetic Survey of the United States. By Dr. L. A. Bauer ~ Smee 6, 285 University and Educational Intelligence .... . 237 Scientific Serials . Heo 5G OR URCREEEEEO Dc Car 23y/ Societies'and Academies.) 2 - . « cme 237 NATURE 241 THURSDAY, JULY 13, 1899. SAUNDERS’S BRITISH BIRDS. An TIliustvated Manual of British Birds. By Howard Saunders. Second Edition; revised. Pp. xl + 776. Figs. and Maps. (London: Gurney and Jackson, 1897-99.) HE demand for works on British birds shows no signs of diminution, the popularity of the present instructive volume being vouched for by the fact of the exhaustion of the first edition of 3000 copies in less than eight years from the date of completion. The first edition being out of print early in 1897, the publishers lost no time in preparing a second, which commenced in November of that year and was completed on the first of June last. That this new issue is in no sense a mere replica of the preceding one is at once shown bya glance at the preface, where it is stated that, while the number of species admitted as British was then 367, it has now been raised to 384. Of course, these additional species are merely stragglers ; and it seems to us that, in cases like those of the frigate-petrel and the black-browed albatross, it would have been decidedly better to include such stragglers in a separate list, as they have nothing whatever to do with the true British fauna. It must, however, be admitted that in making sucha list of foreign stragglers it would be exceedingly difficult to know where to draw the line, so that we are not going to blame the author for the course he has thought fit to pursue. The accounts of the various species, although neces- sarily somewhat brief, are all that can be desired from a popular point of view; and as these accounts are in nearly all cases supplemented by an excellent illus- tration, it may be safely said that there is no other work of its size in which so much information on the subject of British birds can be obtained. The great majority of the illustrations are the same as those in the fourth edition of “Yarrell” ; and although the impressions of many of these do not compare favourably when contrasted with the latter, yet their attractive character and zoological accuracy may well justify their use. New figures, by Mr. G, E. Lodge, are, however, given of many of the species recently added to the British list, while a considerable number of the old-established birds have been redrawn by the same talented artist. A special feature of the work is the carefully compiled synopsis of genera in the introduction, where all the essential diagnostic characters of each are given in simple and yet precise terms. Another notable feature is afforded by the three ad- mirably coloured maps at the end of the volume. The first of these shows the comparative elevation of the land and the depth of the surrounding seas in the United Kingdom, while the second does the same for Europe generally. The former, as the author states, serves to remind the reader that, owing to the indentations of the coast, comparatively few spots in the British Islands are situated at a distance of more than fifty miles from the coast ; and how important a bearing this has on climate —and consequently on bird-life—scarcely needs mention. The third map is a North Polar chart, embodying NO. 1550, VOL. 60] Nansen’s discoveries; and although this is primarily intended to assist in estimating the range of Arctic- breeding species, it will be found highly useful to many others besides ornithologists. Fortunately, Mr. Eagle Clarke’s valuable digest on bird-migration appeared in time for its results to be in- corporated in this volume. And how important are these results in regard to the non-continuation of the Heligo- land migrations to Britain, and also in respect to the effects of wind on migration, needs no telling on this occasion. With regard to the difficult subject of classification, we are glad to find that the author follows the lines of the last edition of “ Yarrell,’ so that the number of families and genera is considerably less than in certain other recent manuals of British birds. We are likewise pleased to see the retention of the old ordinal names, such as Passeres and Gallinz, instead of their fashionable substitutes Passeriformes and Galliformes. So, too, is it refreshing to notice the absence of alliterative names ; the familiar goldcrest, for instance, appearing as Regulus cristatus instead of Regulus regulus. At the same time, it is greatly to be deplored that ornithologists should not, by a system of give-and-take, come to some general agreement over what is really, in one sense, an extremely unimportant matter—v.e. the names and limits of the orders, families, genera, and species of British birds. In the introduction, the author observes that the limits of a genus are mainly—and often purely—a matter of convenience. With this statement we thoroughly agree ; but it is surely a matter of the most extreme 7conventence when each and every writer on British birds adopts his own views on such limits, without any regard to those of his fellow workers. Contrast, for instance, Mr. Saunders’s classification of the Zurdidae (Thrush family) with the grouping of the genera contained therein by Mr. Sharpe in his “ Hand- book of British Birds,” as exemplified in the following table :— SAUNDERS. SHARPE. Fam. Turdide. Fam. Regulide. Sub-fam. Turdinee. 1. Regulus. I. Turdus. Fam. Turdide. 2. Monticola. 2. Oreocichia. 3. Saxicola. 3. Geoctchla. 4. Pratincola. 4. Merula. 5. Rutecella. 5. Zurdus. 6. Cyanecula. 6. Dauilias. 7. Erithacus. 7. Erithacus. 8. Daulias. 8. Cyanecula. Sub-fam. Sylviinz. 9. Monticola. 9. Sylvia. 10. ARuteczlla. 10. Regulus. Il, Saxzcola. 11. Phylloscopus. 12. Pratincola. 12. Acdon. Fam. Sylviidee. 13. Lusctniola. 13. Sylvia. 14. Hypolats. 14. Melizopheluus. 15. Acrocephalus. 15. Acdon. 16. Locustella. 16. Phylloscopus. Sub-fam. Accentorine, 17. Hypolars. 17. Accentor. 18. Acrocephalus. 19. Locustedla. Accentoride. 20. Tharrhaleus. 21. Accentor. Fam. Here we have one author making three families out of what the other regards as one, while he expands M 242 NWATOURE [Juty 13, 1899 sixteen! genera of the former into twenty-one. If specific names were taken into consideration, further discrepancies would be noticeable. Moreover, in many of the other families of birds the two authors do not agree in regard to several of the generic names. For example, in the case of the ruff and reeve Mr. Saunders retains the Cuvierian (Jachezes, while Dr. Sharpe employs the earlier Pavoncel/a. Such differences and idiosyncrasies are irritating enough to the working naturalist who knows what he is about, but to the amateur and the beginner they must be absolutely maddening. Although personally we are inclined to side with Mr. Saunders in regard to the limits of genera, and with Dr. Sharpe in regard to the adoption of the earliest names for the same, we consider both matters of no importance at all in comparison with uniformity of usage. And it is, we think, high time ornithologists settled upon some uniform working basis. Otherwise, we are of opinion the sooner scientific names are given up the better; they were intended for our tools, and we are rapidly making them our masters. In the last few paragraphs we have departed rather widely from our text; and, to revert to the same, we may conclude by expressing the hope that the second edition of the “ Boy’s Yarrell,” as the work before us has been not inappropriately termed, may meet with as favourable a reception from the public as has been accorded to its predecessor. IR Ibs AS REGARDS REGENERATION. Thatsachen und Auslegungen in Bezug auf Regenera- zion. Von August Weismann. Pp. 31. (Jena: Gustav Fischer, 1899.) ROF. AUGUST WEISMANN’S essay on regener- ation, which appeared simultaneously in Watural Science and in the Anatomischer Anzeiger, has now been published in pamphlet form, and well deserves the careful consideration of biologists. Its contents may be divided into two parts, the first of which is independent of the second. In the first part, Prof. Weismann ex- pounds his previously expressed conclusion that re- generation is an adaptive phenomenon—“that the regenerative power of a part is to be considered, not as a direct and necessary expression of the nature of the organism, but rather as a capability which, though it may be absent, is found wherever it is necessary in the interests of species-preservation.” In other words, the power of regenerating lost parts, though depending primarily (like all other vital qualities) on the properties of organised protoplasm, has been defined and perfected in the course of natural selection in those organisms which are in the ordinary course of their life frequently liable to serious mutilation. This is not a new idea, for, as Weismann notices, Réaumur made, in the first half of the eighteenth century, the induction that the power of regeneration was especially characteristic of animals whose brittle body was frequently liable to risk of breakage, and also of those, like earthworms, which are liable to be partially devoured. The Italian naturalist Lessona gave more precise expression to the same in- 1 Lusciniola, for Radde’s bush-warbler, was not known to be British when Dr. Sharpe wrote. NO. 1550, VOL. 60] duction in what is sometimes called ‘“‘ Lessona’s law,” while Darwin regarded the regenerative capacity as in- terpretable on his theory of the selective origin of adaptations. But since the days of Lessona and Darwin the wide occurrence of regenerative capacity throughout the animal series, till it fades away to almost nothing in mammals, has been more adequately appreciated, and besides obsery- ations not a few experiments have been made, so that the literature of the subject is already enormous Weismann, more perhaps than any other, has the credit of having recognised the importance of the problem pre- sented, and of having tried to face the facts with a theory. The first part of the pamphlet is an argument in favour of the interpretation of the regenerative power as an adaptive phenomenon. (1) It has been objected that regeneration sometimes occurs where the loss could only be called a casualty, and not such as would occur in the ordinary course of nature, e.g. a bird’s_ re- generation of a broken beak, or a newt’s regeneration of aneye. But as one inquires further into the matter it becomes probable that these injuries are much more frequent than was imagined, and that they cannot be called casualties. (2) It has been objected that internal organs not naturally exposed to mutilation or periodical wearing out are sometimes regenerated. But there seem to be few cases where this has been really sub- stantiated, though some observations—by Vitzou, for instance, on monkeys—lead us to doubt whether Weismann is quite warranted in saying that regener- ation of brain-cells'in mammals never occurs. (3) T. H. Morgan’s experiments on hermit-crabs showed that all the appendages were capable of regeneration, both those most liable to injury and those naturally well-protected, and led him to the conclusion that there is no relation between the frequency of loss and the regenerative capacity. With this case Weismann deals at consider- able length and with his wonted ingenuity, calling to his aid especially the idea that the variation of the re- generation-“anlage” may lag behind the phyletic trans- formation of the part in question. But is it not enough to say that the fallacy underlying Morgan’s objection is _ that of treating an organism as a finished product, and of assuming that an adaptation must be perfect? (4) It has been objected that regeneration does not occur in many cases where it would be very useful, thus its occurrence among reptiles, as regards the tail, is strangely sporadic, one might be tempted to say capricious. But is not this an argumentum ad tgnorantiam, is it not likely that as we know more about the actual conditions of life in the apparently puzzling cases, the difficulties will disappear? Moreover, must it not be admitted that the absence of regeneration may be explained by the presence of another life-saving adaptation on totally different lines, and that, after all, adaptations are but com- promises, and by no means perfect? Thus it is hardly an argument against the generally adaptive character of regeneration in earthworms to cite a case where the mutilated creature grows a second tail instead of a new head. One might as well say that the quickness of cerebral activity was not an effective adaptation because some people sometimes lose their heads. JuLy 13, 1899] NATCRE 24 3 But we must not prolong our review of this able essay on these familiar lines. Suffice it to say that to those who enjoy this sort of discussion, and who appreciate its ‘serious significance, this last utterance from the renowned biologist of Freiburg—though somewhat more discursive than is his wont—will afford, as the saying is, both pleasure and profit. The second part of the essay contains an attempt to show, not merely that regenerative phenomena are adaptive, and presumably the outcome of selection, but that they are interpretable, on the ontogenetic theory of “anlagen,” “determinants,” “neben-Determinanten,” “reserve germ-plasm,” and the like. This is quite another affair, and altogether too complex to be dealt with in a few lines. But we would venture to insist that the evolutionary or phylogenetic interpretation of re- generation phenomena as adaptive is independent of the subtler developmental or ontogenetic theory of the manner in which the capacity may be supposed to organise and express itself. It seems to us regrettable that Prof. Weismann should condescend to notice the “invectives, sarcasm, and de- rision which have been showered upon” him, and that he should regard “Such utterances as a not exactly desired, but yet not altogether unsatisfactory, sign that the less noble emo- tions of human nature—envy and ill-will—have found cause to direct themselves against the results of my work.” No doubt criticism without knowledge is exasperating, but it is also humbug ; no doubt invective without appre- ciation is irritating, but it is mere pettifogging ; and why should the immortals concern themselves about either ? A more philosophical temper, which we should regard as more deeply habitual, is indicated in one of the paragraphs towards the end of the pampzlet. “One of my critics has compared my ‘theories’ to “towns in the Far West,’ the houses of which are barely erected when they are taken down again to be rebuilt further out in the unknown land. I accept the simile, provided it be not forgotten that the first house of the advancing pioneer must remain standing and in use for a time before the region beyond becomes accessible to further colonisation.” * We would respectfully commend to the illustrious author a motto from a northern University, “They have said, What say they? Let them say.” For the author of the “Germplasm” and “Germinal Selection” is surely, among living biologists, the foremost pioneer. J. A. T. WEST AFRICAN FETISG. West African Studies. By Mary H. Kingsley. With illustrations and maps. Pp. xxiv + 639. (London: Macmillan and Co., 1899.) FOR the last three years Miss Kingsley has been known to the scientific world as a careful collector of facts relating to West Africa, while to the unscientific public interested in works of exploration and travel she is known as a writer with an original and very entertain- ing manner. Her book entitled “Travels in West Africa,” which was published in 1896, was the result of two journeys to West Africa, where she had devoted herself to the study of fetish and fresh-water fishes. In the NO. 1550, VOL. 60] preface to her present volume she tells us that her previous work, which she rather unjustly refers to as ““a word-swamp of a book,” was of the nature of an interim report. She there confined herself to facts, and eliminated as far as possible any inferences that might be drawn from them, distrusting at the time her own ability to make theories, and intending that ethnologists should draw from her collections of material such facts as they might care to select. The use that has been made of the volume since its appearance has certainly justified Miss Kingsley’s method of publication. But there was obviously room for another work on the same subject from her pen. No one was better qualified than herself to form opinions with regard to the beliefs and practices she studied, and we are glad to find that in the present work she has formulated the conclusions at which she has arrived. We welcome the book as a valuable supplement to the first volume of her travels. The book contains a good deal or very varied in- formation, and while some portions of it appeal to the anthropologist and student of religion, others deal with purely scientific observations, and others again are of a political nature. Miss Kingsley’s criticism of the Crown Colony system will doubtless receive the attention it deserves at the hands of those who are responsible for the methods we adopt as a nation in dealing with our tropical possessions. Her chapter entitled “ Fishing in West Africa,” which has already appeared in the Vationaz Review, explains the means by which she was enabled to form the collections which won Dr. Giinther’s admiration ; while in the same connection we have an interesting account of the little fishes (A/est/s Kingsleyae) which have the honour to bear their discoverers name. The most interesting part of the book, however, which Miss Kingsley herself regards as of greatest importance, is the section which deals with the subject of fetish im West Africa. The word fetish is used by Miss Kingsley in a much wider sense than that in which it is generally employed at the present day. The word was adopted into scientific literature from the writings of the old Portuguese navigators, who were the modern discoverers of West Africa. These men noticed the veneration paid by Africans to inanimate objects, and called these things Feitico, a term they applied to their own talismans and charms. The word is nowadays generally employed in a rather similar sense as a general term for the doctrine of spirits embodied in, or conveying influence through, material objects. Miss Kingsley, however, in spite of a protest from Prof. Tylor, has thrown over this established usage, and employs the word as a convenient synonym for the religion of the natives of the West Coast of Africa where they have not been influenced either by Christianity or Mohammedanism. Using the term with this extended application, Miss Kingsley classifies West African fetish into four main schools: the Tshi and Ewe school, which is mainly concerned with the preservation of life; the Calabar school, which attempts to enable the soul to pass_ successfully through death; the Mpongwe school, which aims at the attainment of material prosperity; and the school of Nkissi, which chiefly concerns itself with the worship of the power of the earth. These schools of fetish are not sharply defined, and many of the same 244 NATLTORE [JuLy 13, 1899 things are worshipped indiscriminately in each ; but Miss Kingsley has shown that in certain schools certain ideas are predominant, and her classification is based on a general survey which can afford to ignore minor inconsistencies. It is interesting to note that, according to Miss Kingsley’s observations, the African, to what- ever school of fetish he may belong, conceives of a great over-God, who has below him lesser spirits including man. But this fact does not necessarily support Mr. Andrew Lang’s recently promulgated theory as to the original purity and elevation of the religious beliefs of primitive races, though Miss Kingsley herself is inclined to identify her own conception of things with that she found current among the peoples she studied. We have merely touched on the principal sections of Miss Kingsley’s very interesting work, and have not space to do more than recommend its perusal to all those interested in the religions of the undeveloped races of mankind. The reader will find in it much material of the greatest scientific importance, while its anecdotes and lively style render it one of the most entertaining books of travel and observation that has appeared for many years. OUR BOOK SHELF. Catalogue of the Library of the Royal Botanic Gardens, Kew. (London, 1899.) THE issue of this catalogue fittingly commemorates the development, up to the last year of the nineteenth century, of an adjunct indispensable in the equipment of a centre of botanical research so deservedly famous as the Royal Botanic Gardens at Kew. The many botanists that have enjoyed the access to the library so freely allowed to workers in the Herbarium, and have learned to value the stores of information contained in it, will rejoice to have the catalogue as a guide to render the riches of the library still more accessible than in the past. But not to those alone that can visit Kew Herbarium is it likely to be welcome. Botanists living ata distance that precludes frequent visits to Kew Herbarium will find it most useful for reference as a guide to the literature of botany, and will value it accordingly. The size of the library may be judged from the fact that a rough calculation shows upwards of 15,000 separate entries of books or papers, besides numerous cross- references. Of course, all sides of botanical research are represented, from the more elementary to the most pro- found, from the most rigid study of botany as pure science to its practical applications to industries and arts, to folk-lore, and to its manifold links with other fields of study, scientific and literary. Occasionally one meets with a title that at the first glance seems to have little connection with botany, e.g. W. Ridgeway’s ‘‘ The Origin of Metallic Currency and Weight Standards,” yet these only serve to show the curious relations of botany to other studies. The entries are divided into four series, each arranged alphabetically :—(1) General, occupying 683 pages; (2) Travels, 43 pages ; (3) Periodicals and Serials, 47 pages ; (4) Manuscripts, 15 pages, large octavo. The catalogue has been prepared by Mr. B. Daydon Jackson, and is marked by the accuracy so characteristic of all his work in botanical bibliography. . Despite the peculiar risk of errors in transcribing and printing the titles and necessary details, many of which are in very unfamiliar languages, the freedom from errors is very noteworthy. An introduction to the volume from the pen of the Director of the Gardens gives a brief account of the NO. 1550, VOL. 60] leading facts in the formation of the library, which originated as a public library in 1852, when Miss Bromfield presented to the Gardens the botanical books that had belonged to her deceased brother, Dr. W. A. Bromfield. Sir William Hooker, on his appointment as Director in 1841, had offered to make his large private library and herbarium available for public use if they were suitably accommodated. This was done in a house provided for him as Director until 1852, when they were transferred to the present Herbarium, though still re- maining his private property. In 1854 the late George Bentham, F.R.S., very generously gave his large botanical library to the Herbarium, where in subsequent years he long continued those researches by which he so greatly advanced the science of botany. In 1867, after Sir William Hooker’s death, the Treasury sanctioned the purchase for the library of those botanical works that had belonged to him and that the library did not possess. Valuable legacies and gifts have also been received from other sources, and numerous serials are obtained in exchange; and purchases are made with occasional grants from the Bentham Trust. The sum expended from public funds in the formation of the library has been very small in comparison with its value, and has consisted of a small annual subsidy since 1849, supple- mented after some years by free binding by the Stationery Office. One important source of constant additions—the gifts of books and separate papers from the authors—is largely the result of the benefits experienced by the botanists that come from far and near to pursue re- searches at Kew. The catalogue would become still more valuable to botanists if there could be added a subject-division, even under large sections, of the multitude of titles that it contains. The difficulties of doing so are indeed con- siderable, but the aid to workers would be very great. The Larvae Collectors Guide and Calendar. By J. and W. Davis. Pp. 90. (Dartford: J. and W. Davis.) THE times of the appearances of the British macro- lepidoptera are given in this little book, together with notes on rearing lepidoptera from eggs, larve, and pupe. Young naturalists should find the volume useful in stock- ing their butterfly cages, and as a guide to the manage- ment of insects in the different stages of development. LETTERS TO THE EDITOR. (The Editor does not hold himself responsible for opinions ex- pressed by hts correspondents. Nether can he undertake to return, or to correspond with the writers of, rejected manuscrepts intended for this or any other part of NATURE. No notice ts taken of anonymous communications. ] A Lecture Experiment on the Relative Thermal Conductivities of Various Metals. Most lecture experiments on the conductivities of metals occupy too much time to be very effective, and in addition are often somewhat uncertain in their action. The following arrangement may be very quickly and simply put together, and by its aid the relative conductivities of a number of metals may be quantitatively determined in an interval of about a minute, the essential parts of the apparatus being capable of projection on a screen, A piece of brass tube, about 10 cm. in diameter and 20 cm. in length, is closed at one end by means of a brass disc. A number of holes are bored in this disc to receive the extremities of rods of copper, brass, iron, &c., each rod being 2°5 mm. in diameter and about 15 to 20 cm. in length. The rods are soldered in position perpendicular to the disc. : Each rod is provided with a small index, made from a piece of copper wire of about ‘8 mm. diameter, bent into the form shown in Fig. 1, a small arrow-head of blackened paper or mica being attached by shellac varnish. The rings forming part of each index are wound on a rod very slightly larger in diameter than the experimental rods. To start with, the brass vessel is inverted, an index is slipped Jury 13, 1899] on each rod, the single ring (Fig. 1) being left in contact with the disc, and a very small amount of paraffin wax is melted round the rings. When the vessel is supported with the rods downwards, as in Fig. 2, the solid wax holds the indexes in position. The arrangement is then placed between the con- denser and the focussing lens of the lantern, and boiling water is poured into the brass vessel. When that part of a metal rod, in the neighbourhood of the double ring of the index, reaches the ' Fic. 1.—Enlarged view of index. melting temperature of the wax, the index commences to slip downwards, carrying the wax with it, and when the temper- atures of the rods have acquired steady values, the indexes will have descended to points on the various rods where the wax just solidifies, and which, therefore, possess equal temperatures. Hence, the conductivities of the various rods are proportional to the squares of the distances from the bottom of the brass vessel to the respective positions indicated by the several arrow-heads. Fic. 2.—Lecture apparatus for demonstrating the relative thermal con- ductivities of metals. (The left-hand rod is of copper, the middle one of brass, and the right-hand one of soft steel.) Ascale of equal parts, or, better still, a scaleof squares, may be drawn on the screen, when the relative conductivities may be directly read off. In Fig. 2, rods of copper, brass and soft steel are shown with the indexes in the positions acquired at the end of an experi- ment. It will be seen that the relative conductivities work out to within three or four per cent. of the accepted values for the mean conductivities between o° and 100° C, Royal College of Science, July 8. Epwin Epser. The Electrical Resistance of the Blood. Ir is no easy task to measure the electrical resistance of the blood of a living individual. The principal difficulty depends upon the fact that only very small quantities of blood can generally be obtained at a time. During the last five years many attempts have been made by me to obtain trustworthy and consistent results ; various methods and forms of apparatus have been employed and subsequently rejected. The best results were obtained by placing five cubic milli- NO. 1550, VOL. 60] NATURE 245 metres of freshly-drawn blood between two cup-shaped elec- trodes three millimetres in diameter, coated with spongy platinum, and fixed at 0°75 mm. apart. The average resistance of normal blood at 60° F. measured by Kohlrausch’s method in this apparatus is 550 ohms. A striking, change may be observed in pernicious anzemia, the resistance in this disease being sometimes diminished to about one-half that of normal blood. The deduction is that the blood in pernicious anzemia contains an abnormal amount of salts, due to the destructive metabolism going on. Dawson TURNER. School Laboratory Plans, I HAVE long believed that by far the best arrangements of the benches in a laboratory for elementary chemical teaching is the last one suggested by Mr. Richardson, viz. ‘‘ single benches, cross-ways, like the desks of an ordinary class room.” It must be remembered that qualitative analysis now occupies a secondary place in an elementary course, and a great number of reagents is not required for preparations and simple quantita- tive experiments. The superstructure of shelving may there- fore be replaced by a single rack for the common reagents. This allows perfect supervision from the raised demonstration table in front of the benches, and the work of the class can at any moment be interrupted for explanation or revision of the work done, or for an experiment made by the master himself. It is surely a mistake to divide an elementary course of chemistry into two parts—theoretical and practical ; the proposed arrange- ment allows of the practical work forming a part of the general course. In this county this arrangement has beer successfully carried out. The grammar schools are, however, unwilling to risk the refusal of the Science and Art Department to recognise such a laboratory for earning grants, the old-fashioned benches with uncleanly teak tops and rarely used drawers and cupboards being usually insisted on. T. S. DyMonp. County Technical Laboratories, Chelmsford. The Origin of the Doctrine of Compensation of Errors in the Infinitesimal Calculus. I sHOULD be much obliged if you could help me by inserting a query on this point. Lazare Carnot, at the end of his ‘‘ Reflexions sur la Méta- physique du Calcul Infinitésimal,’’ stated that ‘‘it is singular that in this indispensable condition of elimination the real character of Infinitesimal Quantities . . . should not hitherto have been discovered.” However, Lagrange (see ‘‘CEuvres,” t. vii. p. 595) had explicitly stated this doctrine many years before. Very possibly Carnot did not see this note, but Lagrange again stated it in the preface of his “* Théorie des Fonctions Analytiques,” which Carnot had certainly seen, as he quoted some passages from it in the later editions, at least, of his ‘* Reflexions.” If Carnot has any right toan independent discovery, he could hardly have quoted Lagrange in the first edition of his work. The first edition of both Carnot’s and Lagrange’s works was dated 1797. I have been unable to find a first edition of ‘‘Carnot”’ here, so write to ask if any one can tell me whether there is any mention or quotation of Lagrange in it. Puitir E, B. JOURDAIN. 63 Chesterton Road, Cambridge, June 30. Robert Browning and Meteorology. RoBeRT BROWNING’s well-known description of Aurora Borealis, in ‘‘ Easter Day ” (c. xv. xvii), is so graphic that it must have been written from personal observation. Probably few persons can fully appreciate its accuracy ; but on September 24, in that wonderful Aurora year 1870, just such a display took place, which I had the fortunate opportunity of watching nearly all night from the Welsh hills, when all the phenomena Browning describes, and many others, were abundantly visible. But I can find no account of any such display having been seen in these latitudes earlier in the century, and ‘‘ Easter Day” dates from 1850. The lunar rainbow in ‘Christmas Eve” (c. iv. and vi.), which “‘ rose at the base with its seven proper colours chorded,” 246 NATURE [JuLy 13, 1899 blending at the summit ‘‘in a triumph of whitest white.” with a second bow above it, and ‘‘a wondrous sequence” beyond that, is evidently the hybrid offspring of fancy and that in- accurate observation of phenomena which seems inevitable without scientific training, especially as, while evening service is going on in Zion Chapel, the moon's ‘full face” is shining in the West, and the bow appears in ‘‘ the evpty other half of the sky,” ‘‘North and South and East.” The effect of ‘‘ the flying moon” trying to break out of its “‘ramparted cloud prison” is, however, very graphically described. But I should like to know when and where the poet could have seen his Aurora. BeaWeas: July 8. A Plague of Frogs. Tuis afternoon, as I was walking into Lickey Village from King’s Norton, I came across innumerable frogs. They lined the hedges and covered the road so thickly that I had to walk on tiptoe. I thus proceeded quite 400 yards, where the phenomenon ended as sharply defined as it had begun. Nowhere else along the road was a frog to be seen. I was par- ticularly astonished, as I knew the nearest water to be the Little Reservoir—quite 4+ mile away. The frogs were about ten days old, verysmall. A cottage stood about 300 yards from the beginning of this swarm. Upon inquiry I ascertained that the frogs had thus congregated since noon on Monday, that they had literally besieged the house, jumping allover the ground- floor rooms, that the garden and its paths were full of them. The present occupants had lived there 44 years, but had never experienced anything like this. They have sometimes seen a few frogs cross the road in wet weather. They are now occupied with brushing them out of doors. Can any of your readers explain the cause of this extraordinary spectacle ? King’s Norton, Birmingham, July 5. F. H. Forrey. THE UNIVERSITY OF LONDON. As we went to press last week, an adjourned meeting of the Senate of the University of London was being held to discuss the report of the special committee appointed to consider the offer of the Government to house the University in the Imperial Institute. The history of the negotiations that have taken place may be read in the abridged report published in last week’s NATURE; and the facts contained in that statement formed the basis of the discussion in the Senate. In the end the offer of the Government was accepted, the following resolution, proposed by Sir Edward Fry and seconded by Mr. Bryce, being carried bya large majority : “That the Senate accepts the proposal of Her Majesty’s Government as far as it provides in the buildings of the Imperial Institute accommodation for the work hitherto done by the University ; and authorises the Committee consisting of the Chancellor, the Vice-Chancellor, and Sir J. G. Fitch to settle the formal terms of agreement with the Government, and the Senate reserves the right of the University to hereafter request the Government to make further provision for such further needs as may arise in the future.” By this resolution the question of the future head- quarters of the University is practically settled. The schemes of organisation of the constituent Colleges of the University and future possible teaching centres are now matters of the highest importance, for by them the future work and influence of the University will be determined. An ideal University should encourage the advancement of every branch of knowledge which assists human progress, and it can only do this by admitting into its constitution all subjects with which men of “light and leading” are concerned. It can hardly be held that the University of London has satisfied these conditions in the past, but under the new constitution we may confidently hope that a wider view will be taken of its functions and respons- ibilities. We have no longer to deal merely with a body authorised to confer degrees by examination, but with a NO. 1550, VOL. 60] living organisation taking part in the actual work of instruction. The teachers in this great University will feel that the interests of the University are their own interests, and that their work is not to have for its end the preparation of candidates for degrees, but to en- courage students to work for the dignity and influence of their alma mater. There are several directions in which the work of the University ought to be developed. Law and medicine should, of course, have their Faculties, as they have in the Universities of Paris, Bologna and elsewhere ; and we may surely look to those institutions which have for centuries kept the lamp burning in the absence of a University for the needed heip. Higher commercial education can be provided for by the establishment of a School of Economics and Political Science organised at the Imperial Institute itself. The exceptional facilities offered by the Institute for the work of a school of this character were referred to in an article in NATURE of April 20 in the following words : “ The well-arranged collections of Indian and Colonial products, which form a most important part of the equip- ment of the Imperial Institute, would be found of especial value in illustrating the teaching of that branch of commercial education known as Waarenkunde. No- where else in London do similar facilities exist for in- struction in the technology of commercial products. Within the building, too, has been provided a chemical laboratory, which is now largely used for the examination and analysis of foreign products; and much of the scientific investigation therein carried on, under the able direction of Prof. Dunstan, is an essential feature in the programme of a high school of commerce. Indeed, a large part of the work which entered into the original scheme of the promoters of the Imperial Institute might, it would seem, consistently, and with great advantage to the public, be continued in that Institute under the auspices of a school of economics, industry and com- merce, in connection with the reconstituted University of London. Whether such an arrangement can be effected is a matter for careful consideration; but there is no doubt that the association with the new University of a school of ‘economics and political science,’ under a separate Faculty, suggests a reasonable basis of union between the educational side of the Imperial Institute and the future University of London.” In connection with this suggestion, another point well deserves consideration. The support which the Colonies have given to the Institute has been in some cases with- drawn on the ground that no advantage was derived from it. But with a commercial school at the Institute colonial students could come over to pursue their studies in the midst of collections illustrating the products of their homes, and the training they would receive with such an environment would ultimately be used for the benefit of the Colonies, so that an adequate return would be made for whatever support was given. In fact, it seems that the use of the collections for the purposes of instruction in connection with the new University would satisfactorily settle the question of the service of the Institute to the Colonies, as well as give colonial students an opportunity of obtaining a degree under the very best conditions. If the example is once set by using the Institute collections to illustrate courses of instruction on colonial products and industries, it is to be hoped that the other special collections which abound in London illustrating many other branches of culture may also be utilised for University purposes. With its new resources and facili- ties for advanced teaching, the University is given the opportunity of widely increasing its sphere of influence ; and friends of education and national progress look to it to make the best use of the opportunities which the new headquarters will afford. Jury 13, 1899] THE LIFE OF A STAR. A LETTER FROM PROF. PERRY TO SIR NORMAN LOCKYER. ayoU have asked me to examine certain publications on this subject, and to give you my views on the value of such speculations as have been made by mathematical physicists. Mr. T. J. J. See (Zhe Astronomical Journal, Boston, February 6, 1899) states as “one of the most funda- mental of all the laws of nature” that gaseous masses follow the law K t= R where K is a constant for all stars of whatever mass or of whatever kind of gaseous stuff, R is the radius and ¢ is the temperature. Now we have all sorts of tem- peratures in a star ; but whether Mr. See takes average temperature or thé temperature of some layer at a definite depth below the surface, he is certainly wrong. Mr. Homer Lane does not express the general results which I shall give presently, nor does Lord Kelvin give them in my form (although he does give them); but from either of these classical papers Mr. See might have inferred them, and seen that his own statement was wrong. Mr. See’s arguments are really metaphysical. For example, at the very beginning of the proof of his proposition he speaks of the gravitational pressure at the surface Of a Star, whereas in physics we do not admit that there can be such a pressure in the absence of outside matter. Thus it is impossible for a mathe- matical physicist to get to Mr. See’s point of view. Of A. Ritter’s articles in Wzedemann’s Annalen there is a good abstract in the Astrophysical Journal, Chicago, December 1898. He assumes that the radiating layer on the outside of a star is of constant mass. He also assumes that the rate of ‘radiation is proportional to the fourth power of the average temperature of this layer. He is dealing with temperatures which are so much greater than the temperatures with which we work in the laboratory, that such assumptions must be regarded as quite arbitrary. Mr. Homer Lane, in his classical paper on the theoretical temperature of the sun (American Journal of Science and Arts, second series, vol. |. p. 57, 1870), makes the assumption that Dulong-and Petit’s law of radiation is true for solar radiation, and he uses it to calculate the temperature of the radiating layer, which he finds to be 28,000° F. That is, he uses an empirical law, obeyed possibly at laboratory temperatures in radiation from hot solids, to express the radiation at enormous temperatures from a hot layer of gas which has layers of gas of all sorts of temperatures above and below it. It seems to me that we know too little about the phenomenon of radiation from layers of gas with denser and hotter layers below and rarer and colder layers above to allow of any weight being placed upon these assump- tions of Ritteror Homer Lane. In a star we have layers of fluid at all sorts of temperature and density. Wehave no laboratory knowledge of radiation that is applicable. We know very little about any star except our own sun. During Palzeozoic time, many millions of years, there has been life on our earth. Prof. Newcomb is of opinion that the sun’s heat received by the earth cannot have varied more than a very little during Paleozoic time. My results will enable us to see what this uniformitarian assumption leads to. It is my own belief (see NATURE, p- 582, April 1895) that there may have’ been many millions of years during which the sun may have been radiating at only one-third or one-tenth of its present rate. My formulz will enable us to apply such assump- tions as these, and see what they lead to. However different assumptions of this kind may appear to be, they NO. 1550, VOL. 60] NATURE 247 all lead to results which only differ in’ degree, and not in kind. Assumptions like those of Homer Lane and Ritter may lead to results which are altogether wrong. All this is speculation, but it is speculation on physical and mathematical lines where criticism is immediately applicable to one’s logic and one’s premises. Gaseous Stars. Homer Lane, Lord Kelvin, Ritter, and all people who have tried to make exact calculations, have assumed that the stuff of which a star is composed behaves as a perfect gas In a state of convective equilibrium. I also assume that this is the case. But if we apply our results to our own sun, we find that at its centre there is adensity 33, that is, 50 per cent. greater than the ordinary density of platinum. It seems to me that speculation on this basis of perfectly gaseous stuff ought to cease when the density of the gas at the centre of the star approaches o'r or one- tenth of the density of ordinary water in the laboratory. Let p be density, ¢ absolute temperature, # pressure of the gas at the distance 7 from the centre ; the gas is such that po¢=Z, o being a constant depending on the nature of the gas, and let y be the ratio of its specific heats. Let there be convective equilibrium, so that . (1) « (2) pert ~Y)=c,, a constant . or phila-Y=c,, weonstant! 2)" 4a 4 - Let % and ‘pp be values at the centre of the star. If #z is the mass inside the radius ~, then dp = m — ie dr pe - (3) [I introduce the constant @ because ~ is the gravita- Ayo tional force with which a mass m attracts a mass p at the distance 7 If we keep a=1, all our forces will be in gravitational units. I prefer to have them in laboratory units. If we keep to C.G.S. units throughout, as one dyne is the weight of one gramme at the earth’s surface +981 and the weight of one gramme corresponds to gravitation units, where M, is the mass of the earth i : in grammes and R, is the radius of the earth in centi- metres ; onedyne corresponds to ae gravitation units, 981 Rj? so that a= FT): 1 Also : m=4r "2p. dr sMisiites cx veil iomteintell (4) : 0 (3) is the same as “93 y at ( e Bete am ones (5) From (4), am _ page es Ds =z Fae as P = 4mr*cyzv-1. Hence, differentiating (5), we have Dee AER =X poet ED) a > + + + 2 (6) dr rdr oy tytly-D Let us assume that 7=/,6, and that r=éx, choosing 6 so that x and @ shall not depend upon 4% or py, and that the coefficient of the last term is 1, thus we find a0, 2 ae + aty¥—Y =o : dx? xdx an equation which is true for any star the y for whose gaseous stuff is known. 6 which is ¢/f% may be expressed as a sum of powers ot . (7) 248 , and so tabulated. In the same way, or p/pg might be tabulated. Indeed ¢’ ‘=6. Again p or px*.dx may be 0 tabulated. Mr. Lane has done this work for several values of y. Solution by means of series of powers of x can be relied upon only till x=1. After that one must work indirectly. Lord Kelvin, in a paper published in the Philosophical Magazine, 1887, vol. xxiii. p. 287, gives numbers calculated by his assistant, Mr. Magnus Maclean, from which, with the help of Mr. J. Lister’s or Mr. Homer Lane’s values at x=1, I could give a table like the following for the case of y=1'4. There are outside limits for x and p, which Mr. Lane calls 2 and wp’. Knowing the value of @ for x=1, I find that Lord Kelvin’s numbers give x’ as 5°24, and the corresponding p’ as 2°165, whereas Mr. Lane gives x’ as 5°35, and p' as 2'188. Mr. Lane does not publish the other values, and his curves are drawn to too small a scale for us to be able to make out tables of the values of 6 or ¢. Lord Kelvin from x=o, and Mr. Lane for values beyond +=1, ob- tained their results by methods such that errors may have increased as the work proceeded. On the whole, I am disposed to take Lord Kelvin’s numbers with an 2’, which is the mean of those just given, or 5°30, and p’ as 2°177. TABLE I.—For Gaseous Stuff whose Specific Heat Ratio ts 1"4. x 6 iy BB 10) eee 1000 1*000 vee oO 795 “904 777 “136 "883 "884 "734 "184 993 857 ‘679 *252 I'lq. - ‘819 “607 355 1°33 "763 “508 “512 1°59 “681 "385 ‘758 1°99 “562 237 1°133 2°65 "384 0916 1'666 3'97 on “141 ee "0074 2°117 5°30 Rite {e) ae fo) 25577; _ We know now that for any star whose stuff behaves like a perfect gas a(2 e Bs,3%p,-2/2 7= Al — ane — Deel a : OPO Ei acy eS) 7=1)8, p=poh Where N= a , and B=4rA3, 4na(y—1) we see that A and B, x’ and p’ depend merely on the nature of the gas. We have if R is the outside radius and M is the whole mass. We may choose values of 7) and py, and calculate R and M, or it is easy to see that if we know R and M, we may calculate the internal density and temperature by x M 0 TTA No) 4nmAty’ OR SNE, (isan tees (11) PO amu’ RS It will be noticed that, « being proportional to the molecular volume (being sixteen times as great in hydrogen as in oxygen), py is independent of o, whereas 7) is inversely proportional to o. If we consider our own sun to be made of hydrogen, and if the laws of perfect gases could be applied as we have applied them, % = 3°25 x 10’ degrees centigrade, p, = 33, that is, 50 per cent. greater than the density of platinum (see how I blush). Whereas if it were made of oxygen, py is the NO. 1550, VOL. 60] NATURE [Juty 13, 1899 same as before, but 4% is 2°03 x 10° degrees. It is sometimes good to employ, instead of (8) ne a Mx’ Mx oh epapet ag (22) ~ gmA2Ry!’ PS peRSa! The above tables and these formulz enable us to find the temperature and density at any point in any gaseous star of any mass, size and material (if y is 1°4). The curve connecting @ and x is the 4,7 curve for any star ; the curve connecting @ and x is the p, 7 curve for any star ; the scales of measurement are given in (12). The intrinsic energy (not including any gravitational energy) of the whole mass being %, since the intrinsic energy of unit mass at temperature ¢/ is #7, if & is the specific heat (in ergs) at constant volume, and ¢ is %y Por Y pY~*, rR h=4rnktopy "| rp .dr 0 or h=4nkA*t)?p)X if X stands for Bs | Oy Dax 0 a known number depending only on the value of y. Hence Ee Ete TA? | If W is the work done by gravitation in bringing all the stuff into its present position from an infinite distance, M? Reel » (13) = es We=age | pmr. dr=aV i . + (14) 0 where oa! yi— i xp. dx 0 a known number depending only on the value of y. We can now speculate on these results. If the pieces of stuff which come together to form the nebula are not mere molecules, but of the size of meteors such as reach our earth, W will not be much less than what is here stated. Indeed, we may say that even when a star ceases to be gaseous, and throughout its whole history the value of W is so nearly what is given in (14), that (14) may be used generally in such speculations as these. A gaseous star doubles all its temperatures and its intrinsic heat energy when its radius is halved. We see that if all stars are of the same gaseous stuff, the ratio of % to W is constant for all stars at all times. Let us _. M2 ee put W =a R? Ae RR As W =’+H if H is the total energy lost by the star by radiation, then os. ene a oo ol@G)) As part of this heat was lost by the stuff before it became a spherical gaseous star, we may take as the heat lost from time T = 0 when the radius was Ry to the present time T, when the radius is R Deed a-B M( = 2 x) ( ) RR In the mass M there are surfaces whose areas are proportional to R*, and whose temperatures are pro- portional to + I shall assume as quite reasonable, that Total radiation per year from siete } ccareas x (temperatures)” . (17) where 7 is some constant. JuLy 13, 1899] NATURE 249 It may be worth while here to use with this the assumption that our sun, when gaseous, radiated heat of the same amount every year ; of course H of (15) or (16) is then proportional to time. (15) is the age of the sun from some zero of time until it had the radius R ; (16) is the time taken to contract from radius Ry to radius R. Using (17), Rate of total radiationoR'(7). ao a (Oe) we see that # must be 2 for our sun. In our state of ignorance of the phenomenon of radiation from a star it may be presumptuous in me to say that this would be a very reasonable @ friorz assumption. Namely that rate of radiation is proportional to surface and square of average temperature. Anyhow it makes the task of pursuing the uniformitarian assumption less thankless.! For any star then the total radiation in unit time is proportional to M?, and hence the time taken by any gaseous star in contracting from radius Rg to radius R is Ta au — im . R R being the same for any star, whatever its mass may be. How it depends on the nature of its material we do not know, as we are basing these speculations on an assump- tion as to the sun’s radiation. Or counting age from some period in the nebulous state, which it is not easy to define. Sees ee 5 (19) temperature of star «age x mass. . . . (20) We see that stars get to have higher and higher tem- 1 If total radiation from a star is proportional to surfaces x the #th power of temperatures OA oMmR2-n but from (16), @H___ M2? dR aT R? av Putting these equal and integrating we find T as the time since the star was of radius Ro -3 2-—n Tec(R) -R M a=3 n—3 I. Thus if z=1, I I TeM( ec =) It follows from this assumption that the rate of increase of temperature per Tass annum is proportional to ——, temperature Il. If x=2 as above, I I Ta, —-—. R Ro It follows from this that the rate of increase of temperature per annum is constant and is proportional to the mass of the star. Ill. If x=3, I Ro Ta— log —. MSR It follows from this that the temperature increases with time by the com- pound interest law; that is, the rate of increase of temperature per annum is proportional to the mass X temperature. IV. Iin=4 Tok, (Ro- R). In this case the rate of increase of temperature per annum is Proportional to the square of the temperature. Suppose it to be assumed that the radiation is mainly from an outer layer, that this layer increases in temperature from =o at its outer surface to ¢=¢j at its inner surface, the depth or thickness of it is aR? M~- Thus the thickness of the Jayer is greater with stuff like Hydrogen than with Oxygen. As we really know nothing about how the total radiation from such a layer depends upon the thickness, I cannot use this in my. calculations. It is however worth noting that from equal surface areas of layers all with the same range of temperature but of different depths or Do thicknesses D, the radiation per second oc (3) aos Thus in the case above, in assuming »=2, we are really assuming that the radiation from unit area of layer is inversely proportional to its thickness. Suppose we speak of the depth D’ below the surface to reach a layer of a particular density p, then R* oc M} the depth being independent of whether the stuff is Oxygen or Hydrogen. NO. 1550, VOL. 60] peratures as they get older, until they cease to behave as gaseous bodies throughout. The temperature outside is o. The depth below the surface at which there exists a layer ofa particular temperature, say 5000” Cent. absolute, is proportional to R2/M, or if our rule as to time is right, the depth is inversely as the mass of a star multiplied by the square of its age. In a very old, massive star the layer at 5000° is very close to the outside. It seems to me that this is an important thing. A young star, a truly gaseous star, has great depth of radiating layer. I mean it is probably only at great depths from the free surface that we find the layer from which a continuous spectrum comes. I take it that it is only during collision of molecules that a continuous spectrum is given out ; in the free-path state of a molecule it radiates its own light only. Great density and high temperature conduce to the giving out of the continuous spectrum. In old stars, like our sun, the layer of stuff capable of giving out white light is comparatively near the surface of the star. I can imagine a comparatively young star long before its heat energy is a maximum, not radiating energy very fast, but rather giving out bright line spectra light from the greater part of its area; in fact from all butits central parts. I am very ignorant of your subject, but I take it that any star gives out a continuous spectrum with lines. The continuous spectrum is strong, and the lines relatively dark, in old stars ; the continuous spectrum is weak, and the lines bright, in new stars. In both cases the con- tinuous spectrum is most intense, and the lines least intense at the central parts of a star. If a star is very new, so that it is not all gas, it will probably not be spherical, and one may have spectra quite different in different places and at different times. Stars tn General. I suppose that many people will think the above specu lation to be fairly safe. It is correct on the assumptions. One may apply it to any star until the central density approaches o'r or one-tenth of that of water or even more. In the case of our sun, the theory may have been applicable from the time when his radius was twenty times what it is now until it was five times what it is now. Near the surface I assume the density and temperature to be very small, and probably there is no substance that will behave as a perfect gas near the zero of temper- ature even if its density is also nearly zero. But as the mass of stuff in this condition is small, we may, I think, use our hypothesis. Besides, we are neglecting~more important things; many possible conditions difficult to specify ; heterogeneity ; violent convective rushing of stuff like iron vapour to the places of low temperature where it may undergo sudden condensation and fall as iron hail over large regions; also, intense electrical actions are certainly taking place. All this may be said to be superficial, affecting only a small portion of the whole mass. On the whole, then, we may take our theory of gaseous stars to be applicable to some portion of the life of any star. Iam on much less safe ground when I try to trace the history of a star after its material ceases to behave as a perfect gas, and yet, as I take it, this is very much the longest part of its career. I may only vaguely speculate on its long or short life as a nebula ; as a confused mass of streams of meteors in which every collision generates gaseous masses at all kinds of temperatures ; its record is fairly clear from the time [if there ever is such a period in the truly gaseous state] when it assumes the spherical shape [in all cases I am neglecting rotation] and gets hotter and hotter and smaller and smaller. If the law of radiation is the same in any star as in our sun, and if we take one year’s loss of heat energy by our sun as the unit of energy ; if our unit of mass is the mass of our sun and if the sun’s present radius is our unit of length, I 250 ‘find? [using Lord Kelvin’s popular lecture figures for the (present solar radiation] for any star, Sr ears: Oy) M? A= m = G SE SMG) Sap seer (22) OURO TO On -l -80 “0 Time wa mullions oj years Fic. 1 I must say that when Mr. Lister first worked out this value of % for me I was greatly surprised, for it has been NATURE [JuLy 13, 1899 doubt (see also my final statement) that in a gaseous star the intrinsic or thermodynamic energy in the star is a very large fraction of the whole energy of the gravit- ating matter. Indeed it is so large that one is tempted to look for some greater original store to account for the enormous amount of radiation which takes place, or rather perhaps to assume that no radiating mass can follow the gaseous law. W — represents life in years if we assume a uniform rate of radiation. It has an obvious connection with life under any assumption that we may make. Let us call it life in years; and continue to consider our sun. As the perfect gas law ceased more and more to be true, A, instead of increasing steadily, reached a limiting value and then diminished again, so that eventually Z must become zero. In what state is our sun now? Is itstill very much like a gas throughout, and getting hotter ? ‘It is too much to assume for stuff that would be 50 per cent. greater in density than platinum at the centre. In all prob- ability the change from the law of (22) began before R was 5, was quite marked when R was 4, and / reached its maximum value when R was 4 or 3} or 3._ It is quite certain that Z must reach a maximum value in any star, and afterwards diminish gra- dually, and the simplest mathematical formula expressing this fact may be used instead of (22) to give us useful suggestions in regard to the history of our sun. Such a simple formula is i=o-0W /(1 iF 2 Ro’ =) » eves (23) If R is very great (23) is the same as (22). When R is Ry, 2 reaches a maximum value, and for smaller values: of R, / diminishes. The following tables have been calculated, a different assumption being made for each. W é is calculated from (21). Ro is the radius of our sun (as compared with its present ‘TABLE IIl.—Based on five different assumptions as to the time when our Sun was at its hottest. Also assuming Radiation at present rate. Age of Star in millions Ro=6 Ro=s5 Ro=4 Ro=3 Ro=2 of years. Di Ww] z R DI wWwi-2z W Zar h R D 129‘Q} 2°50) 2°10|14°39|208°3] 2°20) 1:80 | 2°12)14°29) 2°80 12°87 166°7 149°3] 3°28) 2°48)10°96/120°5] 3°53) 2°73 3°32/8"S02) 4°48/6°398 40°16 83°33] 4°30| 2°80/8°433)/69'93] 4°82] 3°32 4°15/6°448, 5°51/5 173 26°39 63°69] 4°96) 2°96|7°337/52°91] 5°57] 3°57 4°5015°573 6°01!4°515 20°20 41°49] 6°14) 3°14/5°898|34°36] 6°85) 3°85 4°94/4 454 6°78|3 699 13°55 29°67] 7°23) 3°23/4°975|24°81] 8:01) 4:01 5°19 3°927, | 7°28)3°198| 10°19 22°47] 8°23] 3°23|4°367|19°16} 9°06) 4°06 5°33/3°508 7°61/2°859 8242 17°79} 9°14) 3°14/3°937|15°53]10'03| 4°03 5°49|3°137 7 '83|2°605 6°832 T2°15J10°54| 2°54/3°413|L1O7I 1°91) 3°91 5°37/2°698 8°07|2 244 )5,072 6°667}14°59| 2°59|2°463/6°1 1615 °52| 3°52 5 08|2°126'4° $04) 1 801)3°226 3°425]20°05| 2°05|1°792|3°226]20'96| 2°96 4°48|1 604, 7°61/1°407/1'976 2'037)25'68| 1’68|1°401|1°961]26'44| 2°44 3°93|1‘291 7'04|1°160)1°346 1'057]35°36) 1°26|1°018/1'037}35"99| 1°89 3°16|'9754)" 603) "9024 8162 generally thought that % is always, not merely much less than W, but exceedingly less. But there can be no 1 In C.G.S. units (13) and (14) give, if the stuff is like oxygen or hydrogen whose y is r*4, =6°36 X10°8M2/R, W=7'079 X 10°8M2/R. In obtaining these numbers Mr. J. Lister took the values of @ deduced from Mr. Homer Lane's curves before we discovered Lord Kelvin’s paper. ‘will be seen that he gets 4/W="o. I It is easy to show that this ratio must , but I am not concerned in getting mathematical accuracy here. htly different from 1'4, we may have the above numbers. NO. 1550, VOL. 60] really be Wf our y is s It | radius) when # was a maximum. Thus the table headed | Ro=4 gives W and 4, T and D on the assumption that our sun reached its hottest condition when it was of 4 times its present radius. I take W—A and call it T theage or Time in years, but all these values of T may be multiplied by some constant, W, # and T are given in millions. | Dis the depth (from surface) of a layer of stuff, say | 10,000° C., taking the depth of such a layer at present as I. Fig. 1 shows how the intrinsic heat energy of our sun JuLy 13, 1899] NATURE 251 has varied with its age on the above assumptions, which | _The values of 2 and of R at the various periods in the are all uniformitarian. The curves and table will suit | life of our sun (or any star) are given in Fig. 2. : any star if the unit of energy employed is the heat The curve for # shows also the rate of radiation, It is radiated per year by the star. Ifa star is twice the mass assumed to have once been more than twice as great as of our sun, the unit of energy is four times as great asin at present in our sun. the case of our sun. A curve connecting R and time is Any other assumption may be tried easily. I myself prefer to think that as a star gets older and as its white light radiating layer gets. | | nearer and nearer its outer surface, its | |. rate of radiation increases. It is quite a) i> possible as I. have shown in NATURE 1-4 | (p. 582, April 1895), that our sun;radiated ] | very little energy during long periods in the past. Without taking an extreme case I will assume that the rate of radiation. gets greater just in proportion to age and so find the following table. TABLE IV.—Rate of Radiation Proportional to Age of Star. ae in z Sa poem R. zt. o4 = 795 “= 16°34 8 oe 11°26 = 10°2 5, en llem ier eae. Aa 7°57 2°0 = 17:0) -@ tux. 6°52 ay saa. walcet asad 370 218 3 5°27 ; ; : = = = = 4°0 25°2 Ss 4°51 Fic. 2. 50 a4 ae ae 3'99 the same for all stars, and in the table the sun’s present ae as He ae se radius is the unit for R. 120 et 43°6 we 2°32 I take the critical size or size of maximum 4% in a star | ABO ca Sap 2 1°71 to depend upon p, the central density ; if then the critical 24°0 a 61°7 a 1°36 radius of our sun was 4 (or 4 times its present radius), | 34°0 te 734 a 1’00 the critical radius of a star whose mass is M times that The values of % and of R at the various periods in the of our sun was 4 8/M. life of our sun are given in Fig. 3. Non-Uniformitarian Assumptions. The numbers in Table II. enable us to find what any assumption as to rate of \ radiation leadsto. Thus, instead of assum- is ing a constant amount of radiation every - Ad year, let us assume in the case of our sun that the rate of radiation at any time was \ always proportionalto %. Let us take the supposition that # was greatest for our sun : a when R was four times its present value. Then as T in the table is no longer to be called time, as it is really W-Z,; let ¢ be | time ; ¢ being some constant. 5 6T =ch. it. | Hence It is quite easy to plot the curve whose 3 05 b E ordinate is a and whose abscissa is T of the table ; in this way using a value of ¢, . i which is suitable, I find TABLE III.—Rate of Radiation Proportional toh. Age in Fic. 3. On no one of the above assumptions can I see that Wi. a millions of R. : h | it is possible to give even a probable limit to the future he pear ; life of our sun as a light-giving body. : | Ce eee Energy in a Spherical Mass of Gas. 3 zoo = 45 527 385 I end this long letter with a very curious statement 4 Sec 09 =| Ae a OF concerning gaseous masses in space, and I am sorry 5 BAG es: 2°75 «2.1 SEGQm meen e406 a Fd 2 248 : ia <8 ma that my own proper work is demanding so much of my 8 256 Xe 458 ‘ 33 S aa attention that I must leave the following very definite “5 284 7-28 ee 352 statement without applying it, as I see that it may be 18 “338 1192 171 2°96 applied, to the study of the physical properties of many 24 “410 T7539 . y-«. 0) SON ae AA. gases. We have seen that, under convective equilibrium,. 34 Geers, .29°205)....., OO MES ISO there is an outside radius beyond which there is no stuff NO. 1550, VOL. 60] 252 NATURE [Jury 13, 1899. existing. The following statement does not assume convective equilibrium ; an outside radius, R, is assumed to exist. f Let temperature, pressure, &c., be functions of ~ If yz is the total mass bounded by the spherical surface of radius 7, dp _ m ip aA . » (24) m=4n [ GIN shies ks) oes » (25) / 0 the stuff being a perfect gas, MS 9 65 6 0 o . (26) If & is the specific heat (in ergs) at constant yolume, the total intrinsic energy of the mass is R haart | rpt . dr, nate o The work that would have to be done in taking suc- cessive layers to an infinite distance is W=+ | ae atfPs v= +4na [pm Lael @2-)) r 0 0 0 Spriidr av patel 5 ake 0 Now (24) is pam= — Es so that R 0 Wie - ar | pt. dr= ~an| dp . . (29) 0 dr “ po Now in (27) R R 70 Fe: / PP dr= [ sa | 7 | = dp. J 0 Py ty fo3 The bracket term is 0, as is o at the centre, and =o at the surface. Hence 27 is -0 h=- gee dp. vs a Dividing by (29) we have eee: W 30 Now in gases, if K is specific heat at constant pressure o=K-—&£s0 that Ls Wis (i=) 93 (7 —2) If y=1}, h=W If y=1'4, h=°833W Here are very definite astonishing statements ! I must confess that I do not understand how if y=1} we can have A=W. It seems to mean that if a mass of this kind of gas gravitates by itself from an infinite distance it retains all its energy. But such gas must surely be imagined to be radiating heat, as it is not at zero temperature. Wherecan it get such heat? I come to the conclusion that there must be atomic energy avail- able somehow in it, even when we imagine the molecules at an infinite distance from one another, or else there is no such gas possible. J say that no substance for which y=1} can behave as a perfect gas. You will notice that we do not need to imagine our stuff in a state of infinite diffusion. If a gaseous star changes its size or the arrangement ofits stuff, the gravita- tional work done is exactly equal to the additional intrinsic heat energy in the star if y is 14. The paradox is greater if we think of coloured diatomic gases such as chlorine, NO. 1550, VOL. 60] which have values of y less than 13. We must either assume that there is more energy available than mere gravitational energy, or else that such substances cannot really behave as perfect gases. [It is to be remembered that by a perfect gas I do not merely mean that /¢p is constant, but that 4, the specific heat at constant volume is constant, a statement which does not follow from the first.] It is some time since I have come across a state- ment which looks better worth study than this one. WILLIAM HENRY FLOWER, K.C.B., FRCS, LL.D. D.CL, SEDMRES. ZS. BES HE distinguished naturalist whose death has recently occurred was the second son of the late Mr, Edward Fordham Flower, the founder of the well-known brewery at Stratford-on-Avon, and dear to all lovers of animals on account of his crusade against the bearing- rein. Sir William Flower was born in November 1831. He was educated at private schools and at University College, London, where he took Sharpey’s gold medal in Physiology, and Grant’s silver medal in Zoology. He became M.B. of the University of London in 1851, and joined the Medica! Department of the Army in 1854, serving in the Crimea, where his health broke down. On his return to England he became Demonstrator of Anatomy at the Middlesex Hospital, and Curator of the Museum, intending to practise as a surgeon. Here he published his first work, “‘ Diagrams of the Nerves of the Human Body,” and also wrote in Holmes’ “ System of Surgery” on “Injuries of the Upper Extremities.” In 1861, at the age of thirty, he was appointed to suc- ceed Queckett as Curator of the Hunterian Museum at the College of Surgeons, and later became Hunterian Professor. Thenceforward he abandoned professional work for purely scientific pursuits. Twenty years later, when he received the Royal medal of the Royal Society, the President stated with justice that “it is very largely due to his incessant and well-directed labours that the museum of the Royal College of Surgeons at present contains the most complete, the best ordered, and the most accessible collection of materials for the study of vertebrate structures extant.” Two years later (in 1884), on the resignation of Sir Richard Owen, Prof. Flower was appointed Director of the new Natural History Museum in the Cromwell Road, where he was incessantly occupied with the ar- rangement and development of the collections until failing health necessitated his resignation, which took effect in October 1898. Unhappily he did not long enjoy the rest and leisure which he had so well earned by a life of unusual industry and devotion to public work. His services in the cause of knowledge were recognised by many honorary degrees from Universities, and by his election as a Correspondent of the Institute of France. He was made C.B. in 1887, and K.C.B. in 1892, and was President in 1889 of the British Association for the Advancement of Science. The mere enumeration of the incidents in a man’s life does not tell very much about the nature and value of his work. Sir William Flower’s chief work was in two directions: firstly, as a director and original artist in museum management ; secondly, as an investigator and discoverer in the comparative anatomy of the Mammalia. Besides these two chief lines of work, there were others to which he gave time and care. He was not unheedful of the popular demand for instruction and guidance by lectures. He frequently appeared at the Royal Institution and the London Institution, and always had a weighty and well-considered discourse to deliver. The most original and, from a social point of view, the most im- portant of these was one on “ Fashion in Deformity,” in which he gave very strong support to those who dis- Jury 13, 1899] approve of tight-lacing, high-heeled shoes, and other monstrosities of clothing. “Another way in which Sir William Flower gave voluntarily a large amount of valuable work to the community was as President first of the Anthropological Institute, and then of the Zoological Society—a post which he held until his death. Such services in our scientific societies are given without any remuneration, and they can only be repaid by the grateful acknowledgment of those interested in the progress of the branches of science thus benefited. To revert to the two chief lines of Sir William Flower’s life-work. He first became generally known in the scientific world by joining the band of young anatomists who supported Huxley in his rejection of the statements made by Owen as to the differences between the brain of man and of apes. Like the other mem- bers of that group—Turner, Humphrey, and Rolleston —Flower published an important contribution to the controversy. This memoir, entitled “Observations on the Posterior Lobes of the Quadrumana,” was printed in the Philosophical Transactions in 1862 ; and about the same time Flower wrote also on “the brain of the Siamang” in the Natural History Review. His most numerous contributions to anatomical science relate to the Cetacea, which was his favourite group. After the deaths of P. J. Van Beneden and Gervais, he was only rivalled in his knowledge of whales by Sir William Turner, of Edinburgh. Flower to have been able to complete the admirable exhibition of whales at the Natural History Museum before his retirement—an exhibition which is not only unequalled, but is not even attempted in any other museum in Europe or America. Next to the Cetacea, the subject on which Flower worked and wrote most was physical anthropology. His catalogue of the anthropological series in the museum of the Royal College of Surgeons | and its introductory chapter have served as classics to amount of patient research. Separate papers by him on the osteology of the Andaman Islanders and of the Fijians are of great value on account of the large amount of material dealt with, and the caution and judgment shown in drawing conclusions. Caution and reticence in generalisation certainly distinguish all Flower’s scientific writings. Whilst he was on this account necessarily not known as the author of stirring hypotheses, his state- | ment of fact gained in weight by his reputation for judg- ment and accuracy. The most important discovery in anatomical science which we owe to him is that of the existence of but one successional molar in the marsupial Mammals. This sharply defined and important fact was only one, but the most striking, of the results of a long, conscientious and painstaking study of the dentition of the Mammalia. The next most striking discovery which we owe to Flower seems to me to be the complete and convincing demonstration that the extinct marsupial called 7hylacoleo carnifex by Owen was not a carnivor, but a gnawing herbivorous creature like the marsupial rats and the wombat—a demonstration which has been brought home to the eye even of the unlearned by the complete restoration of the skull of Thylacoleo in the Natural History Museum prepared by Dr. Henry Wood- | ward. Another thoroughly original and elaborate piece of work which should, I think, be especially remembered the attempt to bring order and system into the study of the forms presented by the lobes of the liver in the Mammalia, an effort which has not, perhaps, as yet borne all the fruit of which it is capable. In such a brief notice as the present a complete biblio- graphy of Sir William Flower’s contributions to anat- omical science cannot be given, but a fair notion of his great activity in research can be obtained from a selected list. Relating to the Cetacea, I would cite the following NO. 1550, VOL. 60] It was a special satisfaction to | MABRORE 253 papers from the Proceedings of the Zoological Society :— On a lesser Fin-whale (Balzenoptera rostrata) stranded on the Norfolk Coast (1864) ; the skeletons of Whales in the Principal Museums of Holland and Belgium (1864) ; on a new species of Grampus from Tasmania (1864) ; on Physalus Sibbaldii (1865) ; on Pseudorca meridionalis, 1865 ; on a Fin-whale stranded in Pevensey Bay (1865) ; the probable identity of Balzenoptera Carolinee and Physalus Sibbaldii (1868) ; on the Whales of the genus Hyperoodon (1882) ; on the Characters and Divisions of the Family Delphinide (1883) ; then in the 7ramsactions of the same Society, the fine illustrated papers on the skeleton of Inia Geoffrensis (1869) ; on the osteology of the Cachalot (1869) ; on the skeleton of a Chinese White Dolphin (1872); on Risso’s Dolphin (1873); on recent Ziphioid Whales (1878); on two species of British Dolphins (1880) ; and the translation of and introduction to Eschricht’s treatise published by the Ray Society. Also in the Proceedings of the Royal Institution, Whales Past and Present, and their probable origin (1883). Relating to physical anthropology, Sir William Flower’s most important works are the following :—The Catalogue of Specimens in the Museum of the Royal College of Surgeons, 1879 and 1884 (already referred to above), in the Journal of the Anthropological Institute ; the oste- ology of the natives of the Andaman Islands (1879) ; the osteology of the Fijians (1880); the osteology of the Mallicolese (1881); the aims and prospects of the Study of Anthropology (1884) ; the Classification of the Varieties of the Human Species (1885) ; on the size | of Teeth asa character of Race (1886) ; in the Proceedings of the Royal Institution (a Friday evening discourse) on the Native Races of the Pacific (1878) ; and in the Man- | chester Science Lectures, a discourse on the aborigines of Tasmania (1866). Ranging over other groups of Mammals, I would cite { _ the following papers :—On a newly-discovered extinct English anthropologists, and are the result of an immense | Mammal (Homalodontotherium) from Patagonia (PA7/. Trans., 1873) ; Description of the skull of a species of Halitherium from the Red Crag of Suffolk (Quart. Journ. Geol. Soc., 1874); on the remains of Hyzenarctos in the Red Crag of Suffolk (zézd., 1877). From the Proceedings of the Zoological Society: papers on the anatomy of Galago (1862); of Pithecia monachus (1862); on the brain of the Echidna (1864), on the brain of the Red Howling Monkey (1864); on the anatomy of Hyomoschus (1867) ; on the development of the teeth in the Armadilloes (1868) ; on the characters of the base of the cranium and the classification of the order Carnivora (1869); on the anatomy of Proteles cris- tatus (1869); and on that of Aelurus fulgens (1870) ; and of the two-spotted Paradoxure (1872); and of the Musk Deer (1875) ; on the cranial and dental characters of the existing species of Rhinoceros (1876) ; and on the mutual affinities of the animals composing the order Edentata (1882). Of a more general character are his articles in the “Encyclopedia Britannica”:—On the anatomy and zoology of the Horse, Kangaroo, Lemur, Lion, Mam- malia, Mastodon, Megatherium, Otter, Platypus, Rhin- oceros, Seal, Swine, Tapir, &c. These have formed the basis of a very useful volume on the Mammalia pub- lished by Messrs. Black, whilst the compact little volume c L | on the osteology of the Mammalia by Sir William in attempting to survey Flower’s anatomical labours, is | Flower is known to all University students. The last volume which came from his pen is one of the best and most interesting, namely that called “The Horse: a study in natural history,” published in 1892. Having thus indicated (and only “indicated” by no means “enumerated” r “fully set down”) the labours of Sir William Blower. th anatomical research, I pass to a brief consideration of his work as a museum curator, which probably took up more of his time and energy than he was able to give to original investigations. This 254 NATURE [Juty 13, 1899 is most certainly true of the second portion of his scientific life, which dates from his appointment in 1884 to the directorship of the Natural History Museum, and was preceded by twenty years of work as Hunterian Curator. There can be no doubt in the mind of any man who is acquainted with the present condition of the public galleries of the great museums of natural history in Europe, and with the condition which characterised those of similar institutions in’ Great Britain previously to the year 1864, that a very great and important change for the better was effected by Flower, first of all at the College of Surgeons, and later in accordance with a further development of his ideas, at the Natural History Museum (British Museum, Natural History). The arrangement and exhibition of specimens designed and carried out by Flower in both instances was so definite an improvement on previous methods, that he deserves to be considered as an originator and inventor in museum- work. His methods have not only met with general approval, and their application with admiration, but they have been largely adopted and copied by other curators and directors of public museums both at home and abroad. In his address as President of the British Association, and also in an address to the Museums Association, Sir William Flower has explained in some detail the theory which he held with regard to the proper selection and arrangement of objects in a public museum. The general conception which Sir William Flower had formed was accepted and developed in detail by that gifted and genial museum-director, Brown Goode, of Washington, U.S. It is simple enough and convincing. But the work of the museum curator consists not merely in framing theories of museum organisation and arrangement: the more important part of his work is the putting of such theories into practice. To do this, energy and patience in the surmounting of obstacles are necessary, and perhaps as much as or more than any other qualitv—the artistic sense. Sir William Flower possessed this last quality in a remarkable degree. No pains were spared by him in selecting the proper colour for the background or supports of the specimens exhibited in a case, or in effectively spacing and balancing the objects brought together in one field of view. He took the greatest pains to make the museum under his care a delight to the eye, so that the visitor should be charmed by the harmony and fitness of the groups presented to his notice, and thus the more easily led to an appreciation of the scientific lesson which each object has to tell. There are public galleries in some of the natural history museums of Europe where the specimens are so crowded and ill- placed, where the lighting is so badly designed and the prevailing colour of case and wall so depressing, that the main purpose of the exhibition is defeated by the fact that the visitor becomes seriously attacked by head- ache before he has been able to ascertain what there is for him to look at, or why he should look at anything at all, in the appalling accumulation spread before him. It was Sir William Flower’s merit to have introduced a better way, and so far as opportunity and the brief four- teen years of his directorship allowed him to do so, he put that better way into practice at the national museum of natural history. The first great principle upon which Sir William Flower insisted was that the possessions of a great museum of natural history must be divided into two distinct parts—to be separately dealt with in almost all respects—viz. the public or show-collection, and the special or study-collection, not exhibited to the general public, but readily accessible to all investigators and specially qualified persons. The latter collection, he in- sisted, should have at least as much space devoted to it as the former. In this way the public galleries would (he showed) be cleared of the excess of specimens which, nevertheless, the museum must carefully preserve for the NO. 1550, VOL. 60] use of specialists. Then, further, Flower held that every specimen placed in the public or show-collection should be there in order to demonstrate to the visitor some definite fact or facts, and so should be moSt fully visible, isolated rather than obscured by neighbouring speci- mens, and ticketed with an easily-read label stating clearly and simply the reason why it is worth looking at —that is to say, what are its points of interest. He would thus have reduced very much in ”zder the speci- mens commonly exhibited in natural history museums, and have increased the zzferest and beauty of each specimen selected for the public eye. Another principle which he often insisted upon—but was not able to put fully into practice owing to long-standing arrangements in the museum over which he presided—was that in the public galleries the skeletons of animals should not be placed in one room and the stuffed skins in another, and the soft parts in a third, and the fossilised remains of extinct allied animals in a fourth more or less remote chamber ; but that the visitor should see, side by side, the stuffed or otherwise preserved animal (mammal, bird, reptile, fish, mollusc, insect, worm or polyp) and its skeleton and important parts of its internal structure and the re- mains of its extinct allies. Thus, there would be, not three or four separate zoological collections for the amazed visitor to traverse and bring into correlation by mental effort, but one only, in which the story of each animal is told as completely as possible in one connected exhibit. It is simply a fact that the “art of arranging museums for the public” is in its infancy, and that it was mainly, if not entirely (so far as natural history is concerned) founded by William Henry Flower. Like other originators, he did not live to see the principles which he advocated fully acted upon, nor did he expect to do so. He knew that time is a necessary element in such developments. But he has left an enduring mark on what we may call “museum policy.” His teaching and performance are producing, and will con- tinue to produce, progress towards the realisation of his ideals. Sir William Flower did not train or produce any pupils. He did his own work with his own hands, and I have the best reason to know that he was so deeply shocked and distressed by the inaccuracy which un- fortunately crept into some of the work of his dis- tinguished predecessor Owen, through the employment of dissectors and draftsmen whose. work he did not: sufficiently supervise, that he himself determined to be exceptionally careful and accurate in his own records and notes. In later years, he had the assistance of young » anatomists in making the beautiful preparations which are placed in the central hall of the museum. One of: his assistants, Mr. Wray, whilst preparing, under Sir William Flower’s direction, specimens for the museum to exhibit the disposition of the feathers in the wings of birds, discovered the strange and puzzling fact that the fifth cubital quill is apparently absent—that is to say, there is a gap where it should be—in whole orders and families of birds, whilst it is present in other orders and families. The discovery of the wide-spread occurrence of aquintocubitalism—as it has been called—was thus made in Sir William Flower’s work-room, and in con- nection with his scheme of museum exhibition. It is well to place on record that Sir William Flower was a convinced Darwinian. At the meeting of the Church Congress at Reading in October 1883, he had the courage to open a discussion on “ Recent Advances in Natural Science in their relation to the Christian Faith,” his expressed object being to mitigate the pre- judices of many of the strongest opponents of the doctrine of evolution amongst the clergy. Whilst discharging in so many different ways important public duties, and holding up amongst scientific men a high standard of accurate work and unremitting devotion JuLy 13, 1899] NATURE 255 to the progress of zoological knowledge, Sir William Flower found time to extend very largely among the educated classes an interest in the aims and results of zoology by the willing courtesy with which he received visitors at the Museum in Cromwell Road, and explained its contents. His interest in his work there was so sin- cere that no zoologist ever asked in vain for his help and advice in museum matters. He was so earnest in carry- ing out his new devices for the effective exhibition to the public of zoological specimens that even on his busiest days he would find a few minutes to show his latest im- provements to one who sympathised with his aims and believed in his methods. Personally, I owe very much to him in this way. Iam glad also to be able to acknowledge here the help which he gave to me by supporting in a valuable letter, which was printed and circulated at the time, the re-arrange- ment of the zoological and anatomical collections in the University Museum at Oxford, which I had proposed and was enabled: subsequently to carry out—largely in conse- quence of the weighty opinion which Sir William Flower gave in its favour. E. Ray LANKESTER. THE DUTIES OF PROVINCIAL PROFESSORS oe NG the past twenty years numerous centres of university education have grown up all over our country, and much public money has been spent in their endowment. Some of these colleges have already risen to the rank of universities with the power of conferring degrees ; others ate eagerly pressing forward in the same direction in the hope of competing with their more fortunate rivals. If this multiplication of universities is not to result in lowering the prestige of British uni- versity degrees, but to enable us to compete in the matter of scientific education with foreign countries, it is of the utmost importance that the professorial staffs of our younger university colleges should be placed under the most favourable positions for establishing the re- putations both of themselves and of their colleges in the matter of higher study and research. The time appears to have come when we must face much more boldly than hitherto the question whether the conditions attaching to provincial professorships and lectureships, even in some of our most successful university colleges, are conducive or inimical to progress in such respects. In calling attention to the serious and, to our mind, unnecessary disadvantages under which provincial pro- fessors are often placed at the hands of their Councils or Governing Boards, our remarks must be understood to be based on a considerable number of experiences of which we have gathered details during some years. A foreign professor may only lecture five hours a week, and devote the rest of his time to research, and yet be re- garded as discharging his duties fully and efficiently. Under such a system German professors have filled their class-rooms with the best students drawn from all parts of the world, German degrees are rising in public esti- mation year by year, English students are going out of their own country for the higher training they cannot obtain at home, and we are mainly indebted to Germany for our standard literature on every branch of science. In America university development is more recent, but the majority of universities are lavishly staffed with professors and assistant lecturers, who thus have ample time for research ; and the system has been introduced of giving these teachers one free year in seven, in order that they may be able the better to keep themselves abreast with the most recent developments of their science. Under such conditions, America is rapidly pressing for- ward in scientific research, and American text-books are slowly and surely finding their way into English class- rooms. NO. 1550, VOL. 60] .In facilities for cheaply acquiring pass degrees. As instances of what one university can do in pro moting research, even in a single department of science, we need only call attention to the Communications from the Physical Laboratory of the University of Leiden, published periodically in English, or the Physical Review, brought out under the auspices of Cornell University. Our modern centres of university education are largely bound down to the policy of attracting the greatest number ‘of students, not by the reputations of their professors, but by the attractions they offer in small bursaries and Under this system a professor may give fifteen lectures a week or more, and spend most of the rest of the day in the laboratory ; but there is no limit to the extraneous work required of him by his Council or Governing Board, beyond that research work forms no part whatever of his obligations. We do not deny that good work is done in this country by many provincial professors, but it is often done under extreme difficulties, and many others are debarred from taking that place in the scientific world for which their abilities qualify them. With regard to the lectures themselves, these are almost , exclusively limited by the syllabus of examinations for pass degrees. Matriculation preparation forms a heavy item in the work of most departments, and one to which great importance is commonly attached. It is the duty of the professor not so much to push forward his best students as to adapt his lectures to the requirements ot the average student, and to bring as many as possible up to pass standard. He is held responsible for the attendance and diligence of his students in class, and is bound to make records of these matters ; while out ot class he and his colleagues are jointly responsible for general discipline, even extending to the rules of athletic clubs. He is required to set and correct exercises and examination papers at frequent intervals. If students have not followed his lectures properly he is expected, often at short notice, to provide tutorial instruction without limit to those whose chances of passing are in danger—an arrangement, by the way, hardly calculated to ensure students giving their best attention to pro- fessorial lectures. We do not imagine that any professor, if left to him- self, would be wanting in willingness to give a large amount of his private time to helping students over difficulties, and making his lectures convey the greatest amount of instruction with the least amount of work. But if a professor makes a conscientious stand against cramming, or puts any personality into his profes- sorial work, he runs the serious risk of losing at a few weeks’ notice the post he has held foryears, at the hands of a Governing Board who misinterpret his action because they have no knowledge of the conditions attach- ing toa sound teaching of his subject. In such cases students, who are more concerned about getting a degree than about the thoroughness of their training, may be called on to give evidence against their professor. We have knowledge of several instances in which colleges have on insufficient grounds lost the services of men who have been doing good work for them, whose teaching has been acknowledged to be successful, and who, under less disadvantageous conditions, would have done them credit by their scientific work. The practical result of this system is that our modern university centres, whether chartered or not, are devoting their endowments to competing for cheap passdegrees with one another, and with private institutions and tutors who prepare for London University and similar examinations. The students spend the whole day in class-rooms and in laboratories, and when they have done the exercise work required by their teachers, the day is gone and they are too tired to ¢himk over what they have learnt. Their professors are thus required to do the thinking for them. 256 NATURE [JuLy 13, 1899 After three years in the mill the students obtain a degree, gained under conditions calculated to minimise what should be one of the most important features in any university training: the learning to think and overcome difficulties for oneself. There is thus a growing annual output of graduates of both sexes who find, often too late, that their qualifications only fit them for one career: that of swelling the ranks of the already overcrowded and underpaid teaching profession. The production of a certain number of schoolmasters is a necessary element in the educational system of every country, but the question is: should this or the advancement of higher learning be the main function of a university endowed with public funds ? Many provincial colleges plead poverty as an excuse for overburdening their staffs with pedagogic and tutorial work. But these colleges are not too poor to vie with each other in the award of small scholarships, many of which go to pass students of no great ability. And experience, both in America and in this country, has shown that if only such objects as endowment of research are prominently brought before public notice, support will not be found wanting. In conclusion, the directions where reform is most needed include the following :— (1) Discontinuance of matriculation preparation—work which naturally belongs to the province of schools and crammers. (2) Recognition of research work rather than tutorial instruction of pass candidates as the main duty of a professor outside his class-room. (3) Reduction of the hours of class work, both of teachers and students. (4) Revision of the now precarious conditions under which provincial appointments are tenable. (5) Attraction of public attention to the importance of providing facilities for professorial research. (6) The appointment of more and better paid assistant- lecturers and demonstrators. (7) A more judicious expenditure of scholarship money, which should be restricted to honours students. If the new university systems of this country are not, in the course of a few years, to take a subordinate position, and their degrees to sink into disrepute, if, in short, we are not to be left in the lurch by our foreign rivals, it becomes the duty of all who are responsible for the management of our provincial colleges and universities to have their attention aroused to a state of affairs which too often results in their professors being sweated and their students crammed. GOVERNMENT GRANT IN AID OF ANTARCTIC EXPLORATION. Ope following letter, referring to a Parliamentary grant in aid of Antarctic exploration, has been received by Lord Lister from H.M. Treasury, and sent to us by the Secretaries of the Royal Society :— Treasury Chambers, July 3, 1899. My Lorp,—I am directed by the Lords Commissioners of Her Majesty’s Treasury to inform you that the First Lord has laid before the Board the memorial signed by your Lordship as President of the Royal Society, by the President of the Royal Geographical Society, and by other distinguished representatives of various branches of science, by which memorial application is made for a Government grant in aid of the expedition now being organised by the Royal Society and the Royal Geo- graphical Society for the exploration of the Antarctic regions. This application has received the careful con- sideration of Her Majesty’s Government, and I am directed to inform you that they are prepared to ask Parliament for grants amounting, in all, to 45,000/. NO. 1550, VOL. 60] towards the expenses of the proposed expedition, pro- vided you are able to assure them that not less than an equal amount will be forthcoming from other sources, so as to enable the scheme to be efficiently carried out. In making this announcement, I am to call attention to the latter part of the speech of the First Lord to the deputation which waited on him on this subject, as in- dicating that Her Majesty’s Government must not be regarded, in making this promise, as inaugurating a new era of ‘more extensive grants than formerly from the Exchequer in aid of scientific enterprises. Rather, it is to be understood that the very exceptional importance ot the present scheme, so strongly represented by the deputation, is being recognised by the promise of a special grant. At the present time, it is only necessary to add that the applications to Parliament for instalments of the grant will be spread over four years, of which 1900-1901 will be the first. I am to ask you to be so good as to communicate this decision to the other signatories of the memorial. I am, My Lord, (Signed) FRANCIS Mowatt. LorRD LISTER, President of the Royal Society, Burlington House. NOTES. THE Paris Academy of Sciences has been authorised to increase its number of national and foreign Correspondants from 100 to 116. THE British Medical Journal announces that Sir John Burdon Sanderson, Bart., and Prof. Michael Foster, K.C.B., will be entertained at dinner by British physiologists on July 20, to congratulate them on the honours recently conferred on them by the Queen. The dinner will take place at the ‘‘Star and Garter,” Richmond. Tue Volta Centenary Exhibition at Como, described in Nature of June 22, has been completely destroyed by a fire, attributed to the fusing of some electric wires. Practically all the precious Volta relics were lost in the flames, notwithstanding the precaution taken to preserve the objects by placing them in a receptacle of solid masonry. The only things saved were a sword of honour presented by Napoleon the First to Volta, a picture by Bertini of Volta explaining his battery to Napoleon, a cast of the great electrician’s skull, his watch, and a few personal relics. Volta’s books and manuscripts, some of which were recently bought by the Italian Government for 100,000 lire, his collection of batteries, the only authentic portrait of Volta, his will, &c., were all destroyed. In spite of the destruction of the Exhibition, the committee has decided that the /étes in honour of Volta shall be continued. The Inter- national Congress of Electricians will be held as previously arranged. Pror. Ewart exhibited a number of his zebra hybrids, their dams, sire, and half-brothers and sisters, at the great Agricultural Show recently held in Edinburgh. The authorities were little prepared for the interest taken in the exhibit, with the result that many thousands either failed to see anything of the hybrids, or had but a passing glance. The Prince of Wales, accompanied by a deputation of the Royal Agricultural Society of England, made a special inspection of the mixed family. From a con- temporary we learn the Prince was so greatly interested that he requested Prof. Ewart to make a similar exhibition next summer at the Royal Agricultural Societies’ Show at York. Should breeders give up empirical in favour of scientific methods, not a Juty 13, 1899] NATURE =) little of the credit will be due to the Prince of Wales recognis- ing the importance of the investigations that have for some years been carried on by the Edinburgh Professor of Natural History. AN international conference organised by the Royal Horti- cultural Society for the purpose of discussing ‘‘ Hybridisation (the cross-breeding of species) and the cross-breeding of varie- ties” was opened on Tuesday. In opening the proceedings, Dr. Maxwell Masters gave an address on the history of the subject. Papers dealing with the experimental production of plant-hybrids and the scientific significance of the results were read by Mr. W. Bateson, F.R.S., Prof. H. de Vries, Prof. George Henslow, Prof. L. H. Bailey, and Mr. C. C. Hurst. Sczemce announces that Dr. Milton Updegraff, professor of astronomy in Missouri University, has been appointed, by President McKinley, professor of mathematics in the United States Naval Observatory. WE learn from the Secretary of the Institution of Electrical Engineers that the reunion of the Institution in Switzerland, from September I to 10 next, is likely to be well attended, and that the final arrangements for the visit are now in progress. It is hoped that a circular giving further details may be issued at the end of the current month. To commemorate the services which the late Mr. H. T. Soppitt rendered to mycological science and to Yorkshire natural history generally, efforts are being made to obtain funds to form a Soppitt memorial library of mycological literature, of which the nucleus should be Mr. Soppitt’s own books and herbaria, which the widow and family are willing to part with for such a purpose. Such further funds subscribed as are not required for the purchase of these, are to be laid out in the purchase of mycological reference-books. The library when formed will be presented to the Yorkshire Naturalists’ Union. Mr. H, H. HOWELL, who joined the Geological Survey under De la Beche in 1850, retires from the service to-day. Mr. Howell, after surveying some portions of Wales and the south of Scotland, and large areas in the midland counties of England, became District Surveyor of the north-eastern counties of England in 1872, he was appointed Director for Scotland in 1882 (when Sir Archibald Geikie became Director General), and he was further promoted to be Director for Great Britain in 1888, Mr. Ernest E, L. Dixon, who has for the. past two years acted as assistant to Prof. Judd at the Royal College of Science, has been appointed an Assistant Geologist on the Geological Survey of England. THE annual meeting of the Society of Chemical Industry commenced yesterday at Newcastle-upon-Tyne. In his pre- sidential address, Mr. George Beilby dealt with the question of fuel and smoke. The magnitude of this problem may be judged from the fact that the total coal consumed in the United King- dom ‘in 1898 was 157 million tons, of which 76 million tons were consumed for the production of power for industrial pur- poses, 46 million for the production of heat for industrial purposes, and 35 million for the production of heat for domestic purposes. The various remedies which have been suggested to reduce this consumption by using coal more economically are (1) improved appliances for the combustion of raw coal, and distribution of the air supply in furnaces ; (2) the transform- ation of the raw coal into smokeless fuel by preliminary treat- ment, either by destructive distillation in gas retorts or in coke ovens, or by its conversion into fuel gas by partial combustion in air and steam, Mr. Beilby considered these remedies, and NO. 1550, VOL. 60] concluded by suggesting that, as a means of bringing all of the different interests which are concerned in this matter into line, the Society should arrange for the holding of a conference on the subject of fuel and smoke, at which the leading technical societies, as well as the actual industries concerned, should be fully represented.—Prof. C. F. Chandler, of New York, was elected president of the Society in succession to Mr. Beilby. THE death is announced of Sir Alexander Armstrong, K.C.B., author of ‘fA personal narrative of the discovery of the North-West passage” (1857) and ‘‘ Observations on Naval Hygiene, particularly in connection with Polar service,” at the age of eighty-one. From the 7Zzmes we learn that in 1849 the deceased was appointed surgeon and naturalist to Her Majesty’s ship Znvestzgator, under the command of Captain (afterwards Sir Robert) McClure, which sailed from Plymouth on January 20, 1850, for the Polar Sea in search of Sir John Franklin. After encountering many difficulties, the Zrveséz- gator, in September 1851, was forced into a bay which Cap- tain McClure named Mery Bay. Here both officers and men suffered great hardship and privation, the food being reduced during the second winter to two-thirds of its original quantity, and the sickness increasing to a great extent, when they were rescued from their perilous position by Lieut. Bedford Pim. In the previous April, Captain McClure had taken a party from the ship and, crossing the strait, reached Melville Island, where he left notice in a cairn that the /nvestigator was icebound off Bank’s Island. This notice was discovered by a travelling party from Her Majesty’s ship eso/wte, under Captain Kellett, who were stationed off Melville for their winter quarters. It was then that Lieut. Pim volunteered to go in search of the ship, which he reached on April 6, 1853, after a journey of 160 miles, which occupied him twenty- eight days. The Znvestigator was then abandoned, and the officers and crew were transferred to the Resolute; but, owing to that vessel being unable to get to the eastward, they were compelled to pass another winter—the fourth—in the ice. Eventually they were transferred to the North Star, and reached England on September 28, 1854. By this expedition the existence of a north-west passage was fully established. Sir Alexander Armstrong was appointed Director-General of the Medical Department of the Navy in 1869, and retired from that office in 1880. AN account of some simple experiments on the best forms of curves for use with gliding or soaring machines for artificial flight has been sent to us by Mr, A. A. Merrill, of the Boston Aeronautical Society, U.S.A. A bicycle wheel was arranged to revolve in a vertical plane upon an axle fastened in a pier. From a point on the wheel a rod projected, and at the end of the rod the surface to be experimented upon was fixed at an observed angle with the plane of revolution of the wheel. The wheel was then started by the fall of a weight joined to the wheel in such a way that when the weight had fallen through a certain distance it became disconnected. After a surface had been fastened to the rod, the wheel was started, and when it had stopped the number of revolutions it had made was shown by a mechanical recorder. Given the same starting force, the number of revolutions would evidently depend upon the facility with which the surface moved through the air. The surface which offered the least resistance to motion was thus obtained. Among other results, the experiments seem to confirm Mr. L. Har- grave’s statement that the existence of a wind vortex under a bird’s wing is an important factor in soaring. A SATISFACTORY report of the committee o: the Albany Museum, Cape of Good Hope, for the year 1898, has been issued. While special attention has been given to the develop- ment of the South African collections, a number of specimens 258 NATURE [Jury 13, 1899 of general interest have been acquired from foreign countries. Dr. S. Schonland, director of the museum, reports that the kitchen-middens near Port Alfred have again yielded a number of interesting specimens. Amongst them were portions of skulls of some human beings (which still await a careful examination) and a number of animal bones, amongst which was the lower jaw.of the Vlakke Vark (Phacochaerus aethtopicus). This animal is quite extinct in Cape Colony now, and it was not previously known that it had occurred at all in that neighbourhood, Dr. Schonland has been able to get some light thrown on a ques- tion concerning the pottery found in these middens, which has hitherto puzzled many ethnologists. More or less large pieces of pottery, with holes neatly drilled through them, have fre- quently been found ; and the meaning of these holes has hitherto been unexplained. It now appears that these pots with holes were used as miniature kilns, technically known as “‘ saggers” (in which smaller pots were burned), and the need of holes through them becomes obvious when the use of these pots is known. IN his introductory lecture, Prof. J. A. Thomson, the newly- appointed Regius Professor of Natural History in the University of Aberdeen, gives utterance to a note of warning as to the direc- .tion in which our biological studies are tending. ‘‘ Amid the -undoubted and surely legitimate fascinations of dissection and osteology, of section-cutting and histology, of physiological chemistry and physiological physics, of embryology and fossil- hunting, and the like, do we not need to be reminded some- ‘times that the chief end of our study is a better understanding of living creatures in their natural surroundings?” He even goes so far as to say that it is difficult to see any reason for adding aimlessly to the already overwhelming mass of morphological and systematic detail. And that what we should rather aim at -is the understanding of the chief laws of organic architecture, of the certainties and possibilities of blood-relationship among diving creatures, and a true conception of what is meant by the term organisation. As has been pointed out elsewhere by Prof, Alfred Newton, such a warning is undoubtedly needed at the present day, when there is far too great a tendency to regard the description of mere structure as the ultimate end of biological research. It is as if some person to whom modern telegraphy were unknown were to describe in great detail the mechanics of the various instruments employed therein without the vaguest conception of their practical use. THE inexplicable habit of snails occasionally abandoning their ‘shells is again alluded to in the July number of the Journal of ‘Conchology. A former instance. recorded was that of pond- snails (Zzmnea), but this time it is land-snails (He/zx) captured at Venice. Here is a case in point illustrative of what is said above—the fact is all very well in its way, but is of no real interest unless we know the reason for such a strange perversity of habit. THE most generally interesting article in the June number of the American Naturalist is one by Prof. Sylvester Judd on the efficiency of some of the protective adaptations of insects in securing their safety from foes. As the conclusions are chiefly based upon the undigested contents of the stomachs of a very large number of birds, it will be obvious that the author has a definite set of facts with which to test the validity of theories— and the facts are by no means always in accord with the theories. ‘Especially is this the case with insects presenting a presumed protective resemblance with the object or ground on which they rest. Grasshoppers, for instance, even when lying still and then most like their surroundings, are snapped up by numbers of birds ; as are also the larvee of ‘‘ looper” moths which resemble twigs, and likewise weevils. On the other hand, hairs, like those of many caterpillars, and, toa minor extent, the stings of NO. 1550, VOL. 60] bees and wasps, appear to be much more efficacious for protec- tion. The brilliant colours of lady-birds seem likewise highly protective. ‘* Warning colours” are, however, by no means always effective inthis respect ; and pungent odours and acid juices (which may be more suited to avian than to human palates) often also fail to save the insects in which they occur. | Tue detailed studies that are now being made of the religious ceremonies of various native tribes of North America by trained American anthropologists are worthy of special study by all students of Comparative Religion, It is now possible, as Dr. J. Walter Fewkes points out in his account of ‘‘ The winter solstice altars at Hano Pueblo” (American Anthropologtst, n.s., i. p. 251), to trace the effect of one cult upon another in mixed populations. Walpi, for example, commenced as a settlement of Snake clans which had united first with the Bear phratry and subsequently with other phratries of lesser importance. The purport of the winter solstice (Zttaz) rites at Hano is to draw back the sun in its southern declination and to fertilise the corn and other seeds, and to increase all worldly possessions. As at Walpi, strings with attached feathers are made and given to men and women with wishes that the gods may bring them blessings. These strings are also attached to beams of houses, placed in springs of water, tied to tails of horses, burros, sheep, dogs, chickens, and indeed every possession which the Indian has and wishes to increase. THE experimental psychologists have passed from testing senses to experimenting on sensations, and ‘‘ The Emotion of Joy” forms the subject of a monograph, by Dr. G. Van Ness Dearborn, in Zhe Psychological Review, vol. ii., 1899. The first series of experiments consisted in recording what the sub- ject said he felt like doing, or would probably do under the ac- cession of hypothetical gifts of ten, one hundred, one thousand, ten thousand and one hundred thousand dollars respectively. The more practical experiments consisted in noting unconscious muscular movements during pleasant or unpleasant conditions of sound, light, smell, &c. It was found that somewhat in pro- portion to its proper pleasantness, an emotional ektramotion consists in expansiveness and outwardly in contraction of ex- tensor muscles; this is true of the smile and laugh of joy. Contraction of the extensor muscles is more pleasant in itself than contraction flexors ; there is a general tendency to flexion under a (naturally unpleasant) sudden shock. IN recent years several authors have published expositions of the methods originated by Hansen in dynamical astronomy ; the text-books on lunar theory chiefly used in this country— Brown’s ‘‘Lunar Theory,” and the third volume of Tisserand’s ‘‘ Mécanique Céleste”—each devote a chapter to the subject. As the ephemerides of the moon given in the Mautical Almanac and the Connaissance des Temps are still calculated from MHansen’s tables, as corrected by Newcomb, the theory cannot be neglected by astronomers ; though in the hopes of mathematicians it has been some- what displaced by the more fascinating work of living writers. In a memoir (Ueber die Differentialgleichungen der Mondbewegung), reprinted from the TZvansactéons of the Leipzig Academy, Dr. Scheibner (who we believe is a former pupil of Hansen) develops systematically the numerous and complicated equations which form the basis of Hansen’s theory of the moon’s motion. The memoir will doubtless be welcome to those German students who have felt the need of something in their own language intermediate in character between the brief account given in Herz’s article in the “*Handworterbuch der Astronomie,’” and Hansen’s own ex- position in the Darlegung. ‘¢SoME Glacial Wash-plains of Southern New England ” is the title ofan essay by Mr. J. B. Woodworth (Bulletin of the Juty 13, 1899] NATURE 259 Essex Institute, Salem, vol. xxix.). These “ wash-plains” or stream deltas and fans constitute a very important feature in the Pleistocene deposits of the region. They form the lowlands on which the greater number of towns and villages are built. To the early settler, they offered flat ground free from the boulders which are strewn over the uplands ; and they yield vast stores of gravel and sand in fairly definite positions. Representing the morainal deposits of a retreating ice-lobe, they comprise the materials spread out at successive stages by streams and rivers which issued from the ice ; and these deposits vary according to their original relations to the frozen mass. Hence the coarse gravels and the finest sands may be looked for in particular areas. No definite relations to sea-level are found among the various wash-plains. It is noticed that temporary lakes were at times produced by the local presence of blocks of ice ; and it is ‘pointed out that the retreat of the ice from the area was so recent that the general form of the deposits and most of their details remain unaltered. Owing, however, to the decay of some of the basaltic and other stones, the surface of the ground has been somewhat lowered. Herr A. WEIGEL, of Leipzig, has acquired the last two remaining copies of Kiitzing’s Zabulae Phycologicae, in 19 vols., with 1900 coloured plates, which he offers for sale at 2400 m. (Kiitzing’s own copy) and 2000 m. respectively. Messrs. DuLAU AND Co., of Soho Square, have issued a catalogue of botanical works, consisting entirely of works on Phanerogamia, which are arranged alphabetically in their natural orders. The same firm forwards also a catalogue of books and papers on British botany, Bulletin 168 of the Cornell University Agricultural Experi- ment Station is devoted to an account, by Prof. G. F. Atkinson, of three species of Fungi which he regards as valuable from an esculent point of view, Cofrinus comatus, C. atramentarius, and C, mzcaceus, with abundant illustrations. Dr. F. SCHLEICHERT has an interesting note, in a recent number of the Waturwissenschaftliche Wochenschrift (June 25) on the observation of phenomena of vegetable physiology in the winter. Many of them, especially those connected with the supply of nutrition, may be followed nearly equally well at that period of the year as in summer. Dr, L. O. Howarp has published an account or the principal insects affecting the tobacco-plant in America in the Year-book of the Department of Agriculture for 1898. Although the plant is said to have no enemies peculiar to itself, it suffers from the attacks of many omnivorous Lefidoplera, especially Sphinges and Noctuze; and from those of various Coleoptera, Hemiptera, &c. WE have received parts 10-12 (published in 1898) of the second volume of a journal called Zavowva, published by the National Society of Agriculture of Brazil. Among the mis- cellaneous contents which fill the magazine, we find a coloured plate of the imago and pupa of a butterfly (He/écontus eucrate, Hiibn.); illustrated articles on a formidable internal parasite (Anchylostoma), and on the history of the wheat-plant; a portrait of the late Prof. Aimé Girard ; notices and figures of Eleusina coracano and indica (forage-plants) ; and much agri- cultural and statistical information, primarily, of course, of local interest, THE first number of Le Mors scientifique et tndustriel—a monthly synopsis of scientific information—has been received. To some extent, the new periodical resembles Sczence Abstracts, but it contains more abstracts of engineering papers, and less cf scientific investigations. The abstracts are concise, comprehen- NO. 1550, VOL. 60] sive as regards nationality, and well printed ; they should, there- fore, be of real service to French readers interested in the progress of pure and applied science. A CAREFUL investigation of tautomeric compounds, 2.é. sub- stances which react as though each possessed more than one molecular structure, though only represented by ove substance, has revealed in a few cases the actual existence of the different structural forms. A very interesting example is furnished by diacetylsuccinie ester, which has lately been studied by Prof. Knorr, At the time of its discovery it was regarded as a single distinct individual, having the formula CH,.CO.CH . CH.CO.CH; coor oor According to Knorr the presence of the other structural isomers has been overlooked from the fact that, though not the most stable relatively, the original compound has the highest melting point, and, being the least soluble, has crystallised most readily from solution. Knorr predicted some time ago the existence of seven isomeric compounds, not including optically active forms, andof these he has already succeeded in preparing five, whilst he considers it very probable that the two missing members will be found. These will be represented by the following formulae :-— CH,.CO.CH.COOR | CH;.CO.CH.COOR Keto-form f representing two representing three inactive forms. cis-trans-forms, CH,.C(OH) : C.COOR CH,.CO.CH.COOR™ Keto-enol-form representing two inactive forms. CH,.C(OH) : C.COOR | CH,.C(OH) : C.COOR Enol-form A RECENT issue of the Zvansactions of the Oxford University Junior Scientific Club contains a valuable account, by Mr. A. F. Walden, of the condition of dissolved substances in solutions other than aqueous. The experiments of Carrara have shown that solutions in methyl alcohol exhibit a progressive ionisation, and that the independence of the ions is as clearly marked as in the case of aqueous solutions. Tessarin has also shown that the molecular lowering of the freezing point of formic acid brought about by the chlorides and bromides of the alkali metals is abnormally high, showing that this solvent also behaves like water. Recent experiments by Franklin and Kraus have shown that liquid ammonia acts as a dissociating solvent. In reference to the hypothesis of Nernst that the dissociating influence of a solvent is related to its dielectric capacity, it is to be remarked that the dielectric constants of water, methyl alcohol, acetone, formic acid, and ammonia are all high. It is pointed out also that these solvents, with the possible exception of acetone, are characterised by having ‘‘associated” molecules. On the whole, therefore, it may be said that the phenomena which it is attempted to represent by the hypothesis of electrolytic dissoci- ation are not peculiar to aqueous solutions. They are, so far as experimental evidence is available, found to be characteristic of solutions of salts in other solvents possessing high dielectric capacities and complex or associated liquid molecules. Accord- ing to Thwing, the dielectric capacity is both an additive and a constitutive property. It increases as the temperature is lowered. The factor of association, according to Ramsay and Shields, also increases as the temperature is lowered. These facts have all to be considered in dealing with solutions and in comparing ionisation determinations made by different methods, Thus we have some explanation of the observation that the degree of ionisation of metallic salts dissolved in methyl or ethyl alcohol is uniformly less when estimated by the boiling point method 260 than when measured by the determination of electrical con- ductivity at a lower temperature. THE additions to the Zoological Society’s Gardens during the past week include a Macaque Monkey (M/acacus cynomolgus) from India, presented by Mr. J. H. Higgins; two Maholi Galagos (Galago maholi) from South Africa, presented by the Hon. Gilbert Johnstone ; two Common Badgers (A/e/es taxus), British, presented by Mr. A. Gorham; a Spring-bok (Gazedla euchore, 8), a Ring-hals Snake (Sefedon haemachates) from South Africa, four Spur-winged Geese (Plectropterus gambensts) from West Africa, presented by Mr. J. E. Matcham; two Lanner Falcons (Fadco /anarius) European, presented by Sir H. H. Johnston, K.C.B.; a Yellow-fronted Amazon (Chrysotes ochrocephala) from Guiana, presented by Mrs. G. F. Cote; a Hunting Crow (Céssa venatoria) from India, a Black-necked Grackle (Graculipica nigricollis) from China, a Larger Rocket- tailed Drongo (Déssemurus paradtseus) from India, a Sacred Kingfisher (7alcyon sancta) from Australia, a Black Hangnest (Casstdix ortzivora) from the Amazons, two Blackbirds ( 7urdus merula), European ; a Brown Thrush (7zrdus leucomelas) from South America, presented by Mr. Russell Humphreys ; an Arabian Baboon (Cynoceshalus hamad yas) from Arabia, three Barbary Partridges (Caccabis petrosa) from North Africa, three Western Pintailed Sand-Grouse (Plerocles pyrenaica), South European, a Grand Galago (Galago crassicaudata) from East Africa, three Black-headed Terrapins (Damonia reevest-unicolor), three Reeve’s Terrapins (Damonia reeves?) from China, a Home’s Cinixys (Cinzixys homeana), a Derbian Sternothere (Sverno- thaerus derbianus) from West Africa, three Reticulated Pythons (Python reticulatus) from the East indies, deposited; four Crested Pigeons (Ocyphaps lophotes) from Australia, an Ostrich (Struthto camelus, 8) from Senegal, a Sun Bittern (Zurypyoa helias) from South America, a Scarlet Ibis (Zudoctmus ruber) from Para, purchased ; a Japanese Deer (Cervus stka, 6), born in the Gardens. OUR ASTRONOMICAL COLUMN. CoMET 1899 a (SwirT).— Ephemeris for 12h. Berlin Mean, Time. 1899. R.A. Decl. Br. h. m. s. . . july 13 TA 3) 13 +13 50°7 . 006 15 I2 26 12 59°9 17 2 el 12 12°1 19 II 45 II 26°9 . 005 21 II 36 10 4471 23 Il 34 To! 356) 7.10704 25 II 40 9 25°1 27 LTS 3 8 48°3 29 12 10 SI Sa ye OlO8 I 12 32 a 73 0e7 August 2 14 12 59 nee a AO. TEMPEL’s CoMET 1899 ¢ (1873 II.). Ephemerts for 12h. Paris Mean Time. 1899. R.A Decl. Br. ek itl Sh Per 7 July 13 20 31 7°6 —14 25 22 14 2 20°5 14 55 18 5 33, 3372 15 25 46 3°418 16 34 4577 15 50 42 17 35 580 16 28 5 is). § sh 3 7mlO ae: 10) 59) 51 LO Mees Bozzi 17 Sl Somers SE500 20 20 39 34°3 -18 4 26 The comet is still on the borders of Sagittarius and Capri- cornus, about 3° west of a and B Capricorni. M. L. Schulhoff points out in Ast. Mach. (No. 3574) that it is important to secure as many accurate observations of the comet as possible NO. 1550, VOL. 60] NATURE [JuLy 13, 1899 at observatories of different latitudes during this apparition, as by this means our knowledge of the mass of Jupiter may be considerably improved. THE New ALLEGHENY OpseRVATORY.—A little over a year ago Mr, J. A. Brashear inaugurated a movement to provide for the erection of a new building and an adequate instrumental equipment for the Allegheny Observatory, and the fund, from numerous subscriptions received, has grown to such proportions that the plan shows every sign of success. Prof. F. L. O. Wadsworth, until recently a member of the staff of the Yerkes Observatory, has been appointed to the directorship, and the plans for the new building have been prepared by him. The largest instrument is to be a refracting telescope of 30 inches aperture, with object-glass by Brashear, and special provision is to be made for astrophysical investigations, which will form the principal work of the observatory. LEEDS ASTRONOMICAL Society.—The /ournal and Trans- actions for the year 1898, lately issued, maintains the excellent standard of former years. Among the many interesting papers mention may be made of ‘‘ The movements of the moon,” ‘Star temples in Egypt,” ‘‘ Astronomy as applied to navi- gation.”” The volume contains two plates, one showing four drawings of Jupiter and one of Saturn made by Mr. H. J. Townshend, and the other a portrait of Mr. T. J. Moore, who has charge of one of the micrometers from the Oxford Observ- atory, with which he is engaged in measuring the plates for the Astrographic Catalogue. Accompanying this is a very lucid description of the work and scope of the Astrographic Survey, by Mr. Moore. THEORY OF THE MOTION OF THE MOON. THE second part of Dr. Brown’s ‘‘Lunar Theory ”’ contains the calculation of the terms of the third order in the eccentri- cities, inclination and ratio of the parallaxes. The first part (reviewed in NaTuRE, November 25, 1897) had already dealt with the general theory, the variation, and the terms of the first and second orders. It will be remembered that the differential equations to be solved are (D + 2)?20 + $®u + Sms — - ee —— > 00, (ues + 27) ° ds hb (D — m)?s+ 4s + 8ru — ess ——— 60, (zes + 27) * Ou (D? = m*)z — — 2 ,=7 40%, (ws +2")? dz The notation is sufficiently familiar to render explanation unnecessary. Dr. Brown’s procedure is as follows :—Let U=Uj tu, +My, S=2, +2 where 7) denotes the variational terms Uy, 2 the terms of the orders already calculated Uy, 2 the terms of the next order to be calculated. Then expanding by Taylor’s theorem the unknown terms enter in the form ¢-(D + m)Pu,+ Mow, + NOa, and D*%z, —-2Mz, M, N being functions of the known variational terms. The unknown terms enter under the same form every time, but if a solution with indeterminate coefficients be assumed, the coefficients in the simultaneous equations that result will depend upon the period of the inequality under consideration, and therefore, from the point of view of numerical solution, entirely different nearly every time. All who have had the practical mee Theory of the Motion of the Moon; containing a New Calculation of the Expressions for the Coordinates of the Moon in Terms of the Time.’’ By Ernest W. Brown, M.A., Sc.D., F.R.S. (from the A7emozrs of the Royal Astronomical Society, vol. liii.). JuLy 13, 1899] experience know how laborious is the solution of twenty simultaneous equations. Prof. Brown estimates the solution of the equations at half the labour of obtaining them, in addition u =e E | 4 | = e | ee fe vie e Fst n = uv 2 | 3 Argument. a Fi | gf o¢ EE 8 & Bo) Cetra oO —-- nook: Pe cc. || MOREE: BS ne mo , : fo) 13 | 206265 | 070002 5 y +/ 18 | 17000 2 3 ée +/ | 21 | 350 ot 4 a D | 9 80 | = 9°05 5 is F II goo0o ool 3 2 +2/ 21a 240 3 7 Po oO It 340 3 8 ee! ERCP) 20) | ee 4 9 ee! +(/-7) 22) | 100 4 10 2 B27 18 6 06 II é? o 10 | = 6 12 Be +2F 20 Aieey | || Cher 3 ye) Cc II 400 o"4 14 | ea D+/ 19 12 oe 15 ea Dre | 20 | 14 ot 16,.| . ° 9 ores | ee 7 ae F+/ 10 15 0°06 18 ye BZ, di, | 45 0°06 19 hel Bays | / 10 u exer 20 he’ F-/ II oe or oh ke D+F 10 | 4 oz 22 é +37 y/ ut gl 23 ee #/ 18 uw ed oa | ae +(2/+7) | 17 Sil 4 25 ee’ £(2/-/’) | 18 3 4 26 ee’ #2 Ne) 8 4 27 ee’? + (2+ 22’) 16 | 5 oe 28 | ceemmee(2—27) | 15 |. (2g 06 2 ee’? 7 17 a BiG 30 3 +37 |) es 03 O‘OL 3 23 i | 16 OES |, 0:1 32 ek? + (7+ 2F) U5) 4 Riga ot 33 eke +(/-2F) 17 30 men i4 34 ek? ari 16 I4 o"4 35 ee | e(24+2F) | 15 | & OT 36 Cent (20-2) 16 | z O57 37 eR +1 We zOnny 4 o7 38 |. ce eer | || | 18 eae’ ® 39 | SD | 7 el 40 celGee (2 2)) | 16 oe u 4r | coMmeD (2-7) | 16) | » Ramey or 42 | ea D+2/ 15 | Sean 0102 43 | ¢?qm D eee | Ors | ie 44 | Pa D+2F 16 O75 | OF 45 ka D | 8 3 O;T 46 | ea® +2 16 Oj), 9 O'T 47 ea? aay if 16 | 0°002) 0'02 48 a D 8 0'001) 0°03 49 As 3F : es 50 | 4am F ake aeae 2 Br | ee F+2/ 10 10 I 2 ke* | F-2/ TON) Ole rors 33 ke | F 10 4mi0 i) 4 54 hee! F+/+/ 10 5 Oe 55 | zee’ iF \| 10 3 se 56 | Acc e— | iL, || 2 or2 57 | «Ae! B-/+/ II 4 O'2 58 he'? F+2/ 10 o's 0°03 59 he’? F-2/ Lo 008 | 03 60 co | F | 10 Cite 2/05 61 hea. D+F+/ 10 ol OZ 62 hea D+F-/ 10 o'2 i 63 | ka D+F+/ 10 | O72 | Riese 64 | ke'a D+F-/ 10 | 0°5 | 07003 65 hea? F 8 | 0'004| 0°06 NO. 1550, VOL. 60] NATURE 261 to the fact that this portion of the work is peculiarly liable to numerical error. He may therefore be congratulated on having obtained an algebraical solution, reducing the operation of finding fresh terms to mere multiplication of series. The mathematical investigation is referred to as destined for public- ation elsewhere, and does not appear in the memoir. The underlying principle is that when in a differential equation of the zth order there are 2-1 integrals known, when the right- hand member of the equation is zero, then a particular integral in the general case can be obtained. In the lunar theory the differential equation is, in effect, of the fourth order, and three integrals are known, two representing the elliptic in- equality and the third a variation of the epoch. For forming the right-hand sides of later stages, the quotient of each set of terms by the variation terms is required. As divisions are troublesome, these quotients are the quantities sought in the first instance: the new set of terms can then be obtained by a multiplication. The quotients referred to are given algebraically as the sum of four products, each product being that of two series. It is inconvenient, in the numerical appli- cation of the above method, that small coefficients often appear as differences of comparatively large numbers. Dr. Brown gives as an example a case where a coefficient 2 arises as the sum of separate coefficients — 6418 + 6496 + 316 — 392 from the above-mentioned four products. Terms of long period require a special treatment, but the general methods apply to the other terms of the group. The loss of accuracy is reduced to that due to the first, instead of the second, order of the small divisor. When the period is that of the elliptic inequality, a new part of the motion of the perigee has to be determined, Calling this new part ¢aje a new unknown term ¢"!(D + 72). #e ca/e appears, and is transposed to the right-hand side of the equation, so that the quantities A, which in other cases are completely known, now appear in the form B+ cj, where B, 4 are known. Dr. Brown has already shown in the first part how ce may be obtained before the coefficients of the inequalities are calculated. When this has been done, one of the equa- tions becomes redundant. Another is already redundant, until the meaning of the arbitrary constant denoting the ellipticity is defined with further precision, Dr. Brown defines the arbitrary constant so that €)—e€) =I to all orders; hence Ay=Aj. The other coefficients A,, A,’ consist of three parts, one proportional to ¢aje, and arising from the quantities 4, a second arising from the quantities B, and a third proportional to Aj. The two equations for which «=o then give a double determination of A», and furnish a check upon the numerical accuracy. Many of the quantities that occur in this arrangement of the computations are of service at subsequent stages. The treatment of the third coordinate follows the same lines, and only differs in being more simple. § The foregoing table exhibits the extent of the calculations already performed, and the results of the first part are for convenience included in it. The decrease of accuracy of the terms in the twenty-second and twenty-third groups is due to the period of one term approximating to the synodic period. Even in these cases, the coefficients are given to less than one-thousandth part of the least quantity that could be detected by observation. Pans INVESTIGATIONS OF DOUBLE CURRENTS” IN THE BOSPHORUS AND ELSEWHERE? AS my books and papers are published chiefly in the Russian language, they are not very well known in this country. A short account of some of my results may therefore not be with- out interest. I cannot, in the course of my address, make you familiar with all my works, and wish at the present moment only to draw your attention to the interesting phenomena of double currents in the Straits of Bosphorus, Gibraltar, Bab-el- Mandeb, Formosa, and La Pérouse. The Strait of Bosphorus joins the Black Sea and the Marmora Sea. The Black Sea water has in it—roughly speaking—half the quantity of salt found in the water of the Mediterranean. 1 Abridged from a paper by Vice-Admiral S. Makaroff inthe Proceedings of the Royal Society of Edinburgh (vol. xxii. No. 4, 18¢9). 262 NATURE [JuLy 13, 1899 © The water of the lower strata or the Marmora Sea has the same “composition as the water of the Mediterranean. The upper Strata, say from ten fathoms upwards, contain water of inter- mediate salinity between the water of the Mediterranean and the water of the Black Sea. This difference in the salinity of the water is the chief reason of the enormous double current of the Bos- phorus. Let usimagine that at a certain given moment the level of both seas is at the same height. The pressure of the column of water in the Marmora Sea will be greater than that in the Black ' Sea; the difference would increase with the depth, and it would disappear at the surface. For this reason, the water in the lower strata of the Marmora Sea rushes into the Black Sea, keeping close to the bottom. That rush of water after a certain time will raise the level of the Black Sea, producing a difference in the level of the two seas, which causes a superficial current to flow out of the Black Sea in the opposite direction to the under current. Here we see distinctly that the principal reason for the double current is the difference in the salinity of the water, and should that difference in salinity cease the double current would be discontinued. The fact is that in the Black Sea evaporation does not exceed the quantity of water supplied by rains and streams, and this excess of fresh water maintains the difference of salinity in the waters of the Black Sea and Mediterranean. The existence of double currents in the Bosphorus was known long ago, and Marsilli in 1681, in his letter to Queen Christina of Sweden, has described them. Later they were somehow forgotten, and some interesting papers have been published, in which the authors try to prove that the double current was legendary. Rear-Admiral Sir W. J. L. Wharton (who is now at the head of the Hydrographic Office) was the first to show bydirect observations that a double current existed in the Bosphorus. I was there a few years after him, commanding the stationary steamer Zaman. 1 began to take observations of the specific gravity of the water at different depths, and I found out that the water forming the lower strata contained twice as much salt as the water of the upper strata ; after this, a double current was quite evident to me. I do not wish to detain you with an account of the different results referring to the velocity of both currents, and will only ‘point out to you that the lower current is similar in many details to an ordinary river, while, on the contrary, the upper current differs much from an ordinary river, probably for the reason that, while the surface of it is falling gradually down, the bottom rises constantly. The difference of level of the Black Sea and :Marmora Sea, calculated from the difference in the specific gravity of the water, I found for the month of July 1882 to be 1°396 feet. In the Strait of Gibraltar I had only five stations, and made my observations one day only. I had no opportunity of measuring the velocity of the current, but the phenomenon is very similar to what I found in the Bosphorus. The water of the Atlantic rushes into the Mediterranean, the difference between the surface levels being, according to my calculations, 0°54 foot. The evaporation of water from the Mediterranean is greater than the quantity supplied by rivers and rains. For this reason, the water becomes more dense, settles down, and goes back to the Atlantic by the under current. I wish to point out here that the temperature of the lower strata of the Mediterranean coincides with the mean winter tem- perature of the air in the eastern part of the sea. This is quite evident, because in winter the temperature of the water to a great depth corresponds to the temperature of the air. In summer, the surface water is much warmer, but this high tem- perature cannot penetrate to a great depth. Iam sorry that I have not time to discuss more fully this question, but in the Straits of Bab-el-Mandeb we have the same phenomena as in the Gibraltar Strait and Mediterranean. Here again—by my observations—the temperature of the lower water strata coincides with the winter temperature of the air at the place where the water settles down. In the three straits already mentioned we have a double current: superficial and bottom current. In the Straits of Formosa and La Pérouse there are also two currents, but both are superficial. { ought to mention that the influence of the rotation of the earth on the direction and velocity of the currents cannot be over-estimated. I shall not discuss this question fully, but the fact that in every salt inland sea there is a circular rotation of NO. 1550, VOL. 60] the water in a direction opposite to the apparent movement of the sun, shows that the rotation of the earth has very much to do with the direction of the currents. In the vicinity of islands, for the same reason, the water follows a direction coinciding with the apparent movement of the sun. It is for this reason also that the water alongside the Chinese coast flows to the south during the north-easterly monsoon as well as during the south-westerly monsoon. The Kuro-Siwo current going to the north and north-east cannot touch the Chinese coast because there is brackish water flowing to the south-west. In the Strait of Formosa the specific gravity and temperature of the water at the Chinese coast are quite different from what is observed off the coast of Formosa. This difference in the temperature and specific gravity may give to a sailor a good guide for a fair passage through the Strait. The temperature of the water, say, in the month of February at the Chinese coast is 11° C., while at the coast of Formosa it is 20°. If the captain will try during the month of February to follow the line of the temperature of 15° he will pass at a good distance from the dangers of both coasts. Moreover, at the Chinese coast in winter it is possible to find water at less than 1I‘0240 (si), while at the coast of Formosa it is seldom less than 1'0265. Every sailor knows how difficult is the passage through the Strait of Formosa. During the north-easterly monsoon the weather is very thick, and the depth of the sea cannot in these places be regarded as giving a good means for determining the position of the ship. It may happen that after a ship leaves, say, Nagasaki the captain never knows his position until he runs on the Chinese coast and wrecks his ship. My opinion is that a regular temperature service should be arranged from Turnabout Lighthouse ; everyday a pilot boat should put to sea, taking temperatures both going out and returning, and the tem- perature of the water should be wired to all Chinese and Japanese ports for the information of the captains. By these means many ships would be saved from danger. | The currents in the Strait of La Pérouse are very complicated. There is a very narrow and long strip of cold water, which lies in the direction from N.W. to S.E. ; a vessel crossing that strip in July may have temperatures of 18° C., then 5°, and again 16° or 18°. It would take me too long to explain the source from whence the cold water comes, and why it is constantly there ; it is the cause of fogs which render navigation in that place very difficult. I may briefly say that the Kuro-Siwo current partly enters the Sea of Japan, and the excess of water escapes partly through the Strait of La Pérouse into the Okotsk Sea. Due to the rotation of the earth, the current turns to the south-east and flows alongside the Island of Yezo. This water is warm and dense, having much salt init. The water of the Okotsk Sea— particularly in the vicinity of the Island of Saghalien—is in summer also pretty warm, but it is much lighter than the water of the Kuro-Siwo, and thus while the denser water sinks down, the lighter water tries to rise on the top of it. The difference of level which is produced hereby brings to the surface the cold water of the lower strata. I studied this Strait in 1887 and 1888, and published the results of my study, but when I came to the Pacific again in 1895, as the Admiral commanding the squadron, I was very anxious to go to the Strait of La Pérouse to re-investigate the currents, and now I am in possession of very valuable material on this subject, which is almost ready for publication. I do not propose to take up more of your time at present with particulars of these five straits. I only wish to remind you what important information the thermometer and hydrometer can give in the study of the different parts of our so little-known planet. You know better than I that studies in that direction ought to be continued, and no nation in the world has been so liberal as England, which found means to send out for four years the Challenger with a scientific staff to explore the deep sea. But it is not always possible to find such means, and it is advan- tageous to associate ordinary seamen with that kind of work. I should be very glad if oceanographers would come to certain definite opinions with regard to the mode of collecting the information about the temperature of the surface water. It would be a great advantage to knowledge to divide the study of the sea with regard to the temperature. Suppose Russia should take Okotsk Sea, Bering Sea, or Sea of Japan, Black Sea, White Sea, Kara Sea, and the Finnish Gulf, England takes | the Atlantic, United States takes Northern Pacific, Germany Juty 13, 1899] NATURE 263 takes Indian Ocean, France takes South Pacific, Sweden and Norway take North Sea, Baltic Sea and the Arctic Sea. Every nation should extract the information in regard to the temperature from ships’ log books, put it in tables of approved description, and send it to the corresponding nation; this will give means to collect enormous information. The observations of every ship in a certain square ought to be placed on a separate card, Boxes containing these cards, say for the North Pacific, would not occupy more space than can be found in a good-sized book-case. When a new journal of a ship is received, temperatures of sea water observed on board that ship should be placed on the cards, and the cards put in their corresponding place. In this way we should, each year, become richer in the knowledge of the temperature of the surface water, and no observ- ation would be lost. Every observation would increase our knowledge of the temperature of sea water. It would be a real pleasure to see that progress of knowledge, and if ever this system or any other system be accepted, it will help us to study many details which, up to the present time, are unknown. UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Mr. R. L. JAcK, Government Geologist, Queensland, now on a visit to this country, is to receive the honorary degree of LL.D. of Glasgow University on July 20, Mr. E. A. MINCHIN, Fellow of Merton College, Oxford, has been elected to the Jodrell Professorship of Zoology in University College, London, in succession to Prof. W. F. R. Weldon. THE Bill for establishing a Department of Agriculture and Technical Instruction in Ireland was read for a second time in the House of Commons on Thursday last, and referred to the Standing Committee on Trade. For the purpose of encouraging the study of botany, the London Technical Education Board have had the botanical gardens in Battersea, Ravenscourt and Victoria Parks laid out upon an organised plan. Good collections of plants, represent- ing various natural orders, have been obtained, and suitable arrangements have been made for the convenience of teachers and students. The more important trees and shrubs in the parks have been labelled, and lists have been supplied for insertion in the botanical guide which the Board proposes to issue shortly for the convenience of students. Teachers of botany can obtain tickets for themselves and pupils for admission to the botanical gardens at the Battersea, Ravenscourt and Victoria Parks by application to the Secretary of the Board. By the recent gifts of Mrs. Stanford (Sczence states), Leland Stanford Jr. University becomes the richest university in the world, far surpassing in its resources Harvard, Columbia, or any other university. The resources of the University consist of three great farms, aggregating 95,000 acres of land, deeded by Act of Legislature. On one of these farms, which constitutes the University Campus, buildings to the value of one million dollars were erected before Senator Stanford’s death. By his will the University received 2,500,000 dollars in cash, invested in interest-bearing bonds. During the litigation following his death, Mrs. Stanford gave to the University (by deed) her own private fortune, amounting to about a million dollars, By her recent gift she transferred the residue of the estate to the Uni- versity, it being necessary to do this by deed of gift under the laws of the State. The property just transferred has a com- mercial value—judging from the revenue stamps put upon the deeds—of 35,000,000 dollars. What its actual value may be only the future]can determine, The income arising from this final gift is at present relatively small, as by agreement among the railroads, in bonds and stock of which it largely consists, the earnings are fora time to be used in freeing the property from debt and in making improvements. Ar the annual dinner of the Old Students’ Association of the Central Technical College, held on Thursday last, Prof. W. E. Ayrton, in proposing the toast of the Association, referred to the progress of the College and the insufficiency of accommo- dation due to the continued increase in the number of students. He announced that the electrical department would soon be NO. 1550, VOL. 60] greatly extended by the erection of a large new dynamo room nearly six times the size of that at present in use, and occupy- ing a considerable part of the ground floor of the new building of the Royal School of Art Needlework adjoining the College. The accommodation for this department would be further Increased by the completion of a new drawing office and a new lecture theatre. Sir Philip Magnus, in proposing the toast of the College and its professors, remarked that the College was that day entering on a new period in its career, for it was likely to become an integral part of the new University of London, which had decided the day before to move into new quarters at the Imperial Institute next door to the College. The needs of the College were recognised in the new University by the decision to appoint a faculty of engineering for the first time in the history of University education, and by the variation of the University matricula- tion examination to suit the requirements of different classes of students. Prof. Armstrong, in replying to the toast of the Chairman, alluded to the research work done at the College, especially in relation to its value as a means of mental training. SCIENTIFIC SERIALS. Bulletin of the Amerian Mathematical Society, June.—Prof. F. N. Cole reports the April meeting of the Society held in New York City, and summarises the thirteen papers which were contributed. He also indicates where the papers themselves may be or will be found.—Surfaces of revolution in the theory of Lamé’s products is a paper which was read by Dr. Safford at the February meeting. It is a review of an article by Haentz- schel (reduction der Potentialgleichung), in which that writer criticises results obtained by Wangerin in the Berliner Monats- berichte (February 1878). Dr. Safford agrees with Wangerin in the results he gets, and so, in his opinion, invalidates Haentz- schel’s criticisms. —The next article is an enthusiastic review by Mr. Arthur Berry of Picard’s ‘‘ Théorie des Fonctions Algé- briques de deux Variables indépendantes,””—Another review is one of Jules Tannery’s ‘‘Lecons d’Arithmétique théorique et pratique,” by Prof. J. Pierpont. This latter is pronounced to be the first work on arithmetic which the reviewer has seen which, while intended entirely for secondary instruction, is written in accordance with the new ideas regarding the number concept and the need of rigour. Thus it is a pioneer ofa revolution in secondary instruction.—Dr. L. E. Dickson con- tributes a note on Page’s ordinary differential equations (cf a review of this by Prof. Lovett in the Bz//etin, April 1898).— The usual notes and new publications close the number. In the Journal of the Royal Microscopical Society for June, besides the usual summary of current researches in zoology, botany, and microscopy, is a further instalment of Mr, F. W. Millett’s report of the recent Foraminifera of the Malay Archipelago; and an article by the president, Mr. E. M. Nelson, on the rackwork coarse adjustment, in which he traces the history of the application of rackwork to the focussing of the microscope from the time of Bonannus in 1691 down to the most recent improvements. THE Journal of Botany for July contains an article, with illustrations, on a new British fresh-water alga, by Dr. A. B. Rendle and Mr, W. West, jun. The alga is a new species of the interesting genus Pithophora, first found by Wittrock ina tank in Kew Gardens. Like Wittrock’s species, however, it has no claim to the title of ‘‘ British’ beyond the fact that it was found in a canal near Manchester, where it had unquestion- ably been introduced with cotton-bales. The remaining papers in both the June and the July numbers appeal to those interested in descriptive and geographical botany. SOCIETIES AND ACADEMIES, Paris. Academy of Sciences, July 3.—M. van Tieghem in the chair.—Considerations on the physical constitution of the moon, by MM, Loewy and Puiseux. A summary of conclusions ar- rived at from recent photographic study of the moon. Certain 264 NATURE [JuLy 13, 1899 comparisons are drawn between the structure of the moon’s surface and that of the earth, and evidence is adduced of the existence, at the present time, of a remnant of the original lunar atmosphere. —Examination of sea-water drawn from different depths: variation of iodine compounds therein, by M. Armand Gautier. Examination of water taken from the sur- face of the Mediterranean shows, as has been previously found to be the case with the Atlantic Ocean, the entire absence of iodides and iodates, the whole of the iodine present being con- tained partly in microscopic organisms and partly in combin- ation with a complex organic substance which contains nitrogen and phosphorus, and is capable of dialysis. The total amount of iodine present is nearly the same for all depths, but the form in which it exists varies considerably. Thus, at the bottom of the sea iodine exists in the form of iodides and iodates to the extent of 0°305 milligramme per litre, and the quantity decreases with decreasing depth until it disappears altogether at the surface. On the other hand, the iodine con- tained in living organisms is greatest in amount at the surface, and gradually diminishes as the depth increases. The iodine present in the form of soluble organic compounds is much more constant in amount, the maximum quantity being found at a depth of 880 metres. The water of the Mediterranean appears to be somewhat poorer in iodine than that of the Atlantic, the total quantities found being 2°25 and 2:40 milligrammes per litre respectively.—Observations of Swift's comet (1899 a) made with the Brunner equatorial at the Lyon Observatory, by M. J. Guillaume.—On the suppression of trial methods in the calculation of parabolic orbits, by M. L. Picart.—On the transformation of surfaces, by M. E, O. Lovett.—On the surfaces of Voss, by M. C, Guichard.—-The groups of the order 16 A, A being an odd prime, by M. Le Vavasseur.—On the development of a uniform branch of analytic functions in a series of polynomials, by M. Paul Painlevé.—On two integrable equations of the second order, by M. E. Goursat.—On a class of equations to partial derived functions, by M. Ivan Fredholm.—Considerations on the works of MM. S. Lie and A. Mayer, by M. N. Saltykow. —Wandering globular sparks, by M. Stéphane Leduc. When two fine metallic points are connected with the poles of an electrostatic machine, and placed in contact with the sensitive film of a photographic plate resting on a metal surface, an effluvium is produced around the positive point, and a luminous globule appears at the negative point. This globule increases in size, detaches itself from the negative, and slowly wanders towards the positive, point; on reaching the latter the lumin- osity ceases, and the machine is found to be discharged. The phenomenon suggests a comparison with globular lightning. — The frequency of nervous oscillations, by M. Auguste Char- pentier.—On the nature and cause of the phenomenon of coherers, by M. Thomas Tommasina. An account of further experiments on the formation of conducting chains of metallic particles in coherers.—On the position of the points of magnetic ‘transformation of nickel steels, by M. L. Dumas. The influence of chemical composition on the magnetic properties of steels is described and discussed. —On the volumetric estimation of zinc, by M. Pouget. In the new process here described the solution of zinc is treated with hydrogen sulphide and the precipitated zinc sulphide decomposed with a known amount of iodine solu- tion, the excess of the latter being subsequently determined by titration with thiosulphate.—On the preparation and properties of the arsenides of strontium, barium, and lithium, by M. P. Lebeau. The arsenides of the metals in question were obtained by the reduction of the corresponding arsenates with carbon at the temperature of the electric furnace. They are reddish- brown substances presenting a crystalline fracture, and are rapidly decomposed by water with evolution of hydro- gen arsenide and formation of the hydroxide of the metal.—A study of methylic oxymethylene-cyanacetate and some of its homologues, by M. E. Grégoire de Bollemont. Methylic, ethylic, and amylic oxymethylene-cyanacetates have been prepared from the corresponding ethereal salts, which have been previously described. These compounds exhibit the char- acteristics of strong monobasic acids, and may be looked upon as substitution derivatives of formic acid.—The use of tetra- chlorohydroquinone for the characterisation and separation of fatty acids, by M. L. Bouveault. Tetrachlorohydroquinone reacts with one and two molecules of the chlorides of fatty acids to form stable, well-crystallised compounds which are easily purified, and thus eminently adapted for the identification, and NO. 1550, VOL. 60] in some cases for the separation, of the acids. The physical properties of some of these compounds are described.—On the ' presence in the animal organism of a soluble ferment which reduces nitrates, by MM. E. Abelous and E. Gérard. Ex- periments are described which show that the various organs of the body contain, in different proportions, a soluble substance of the nature of a ferment which reduces nitrates to nitrites. A temperature of 20-40° is most favourable to the reaction, which ceases altogether at _72°.—On the reducing power of urine, by M. Henri Hélier. The author determines the reducing power of urine by titration with potassium permanganate solution in the presence of sulphuric acid, the result being ex- pressed with reference to urine of normal concentration, as measured by the amount of urea present. In many diseases, the reducing power is characteristically higher or lower than the normal.—Contribution to the study of the bark of Rhamnus purshiana (Cascara Sagrada), by M. Leprince. The presence is demonstrated of chrysarobin, chrysophanic acid, and emo- dine.—Direct transformation of acetamide into ethylamine by hydrogenation, by M Guerbet. The reduction is effected by means of metallic sodium in the presence of boiling amylic alcohol.—On the secretion of diastases, by M. Dienert.— Peculiarities of the eruption of Vesuvius, by M. Matteucci. CONTENTS. Saunders’s British Birds. By R.L. ....... 241 As Regards Regeneration. ByJ.A.T. ..... 242 Westra frican) Fetishie mmm Mises tel. ¢- tei meres Our Book Shelf :— ‘Catalogue of the Library of the Royal Botanic Gardens, Kew” 366 (OME eg a al Davis (J. and W.): ‘The Larvz Collector's Guide and Calendar”. .SceeeenenCic: + +) +) oat eme A Letters to the Editor :— A Lecture Experiment on the Relative Thermal Con- ductivities of Various Metals. (J//ustvated.)— Edwin Edsertueacmeecne: = « «nema The Electrical Resistance of the Blood.—Dr. Dawson Stitdlgoes Gus og 4 6 6 Gio eOEEIDo 5 o.6 > School Laboratory Plans.—T. S. Dymond .. . . 245 The Origin of the Doctrine of Compensation of Errors in the Infinitesimal Calculus.—Philip E. B. Jourdain! |). {ey tee men elie te. /> |cieal eanene Robert Browning and Meteorology. By B. W.S.. 245 A Plague of Frogs. —F. H. Fortey. ..... .. 246 he University of London. . - . + - inl mnuee4o The Life of a Star. (Wzth Diagrams.) By Prof. JafPerry, F..RiS se eeemeen Seni). =. (ieee meey William Henry Flower, K.C.B., F.R.C.S., LL.D., DiC... Sc. Di; WaReSeehe219., 0). 12-5. bysbrots Ev Ray ankestenslaReoumit-) -7- - - -teaneutemnneesc The Duties of Provincial Professors .. . ... . 255 Government Grant in Aid of Antarctic Exploration 256 LS). Mii i O'S ob 14 eMoD Tg Yolo ol) BRO Our Astronomical Column :— Gomet:1899.ai(Swifk)emeeeecres Gli. = =: | eeeneinen eRZOO Tempel’s Comet ‘1899 ¢ (1873 II.). . . ..... + 260 The New Allegheny Observatory ....... . . 260 Leeds Astronomical Society ..... . . 260 Theory of the Motion ofthe Moon. By P,H.C. . 260 Investigations of Double Currents in the Bosphorus and Elsewhere .,..iureeiieec = + EOL University and Educational Intelligence ..... 263 Scientific Serials .... Pie (ite |). TSR EzOS Societies and Academiesimuss:) -0-0- -°- |») me EzOS VA Oa Ss 265 THURSDAY, JULY 20, 1899. PRESTWICH AND PRACTICAL GEOLOGY. Life and Letters of Sir Joseph Prestwich. Written and edited by his Wife. Pp. xiv+444. (Edinburgh and London: Wm. Blackwood and Sons, 1899 ) HIS is a pleasantly written personal history of a well- known man, and as such interesting to his friends who survive him and to the numerous friends of his friends who have passed away but are spoken of in con- nection with him. Scientific inquiry, however, filled so large a part of his life, and he did so much for the elucid- ation of certain branches of geological inquiry, that the story cannot fail to be more or less an account of the progress of research along those lines to which he devoted himself. Born of a good north-country stock, Prestwich was sent to school while very young, and although people took a fancy to the spirited boy and were kind to him, he must have had to rough it somewhat in childhood. At sixteen he entered at University College, London, where he worked hard and successfully, but confined his attention, unwisely as he allowed in after life, too much to chemistry and natural philosophy to the neglect of mathematics and classics. Yet it must not be supposed that he was a one-sided man, for he carefully apportioned his time when it was more at his own disposal, and went through a very full if not severe training. His extensive reading in English literature and his knowledge of the French language, acquired when a boy at school in France, and kept up in after life, proved of the greatest assistance to him. Joseph Prestwich, jun., was soon well known in the scientific world, and those social qualities and that genial temperament which made ‘“ Uncle Jovis’ parties” so delightful to the happy children he loved to gather round him, enabled him also to do much to further the co-operation of scientific workers, and ‘ Prestwich’s Easter excursions” were not less highly appreciated by the geologists who had the privilege of joining them. These excursions were certainly very pleasant and | profitable. They were thoughtfully planned and well- managed. The party, generally consisting of one carriage load, met at some appointed spot. A few put their heads together when invited by the leader to do so, details were arranged, orders as to hours were given— these often involying a very early start—a call all round for say 10/., which was carefully administered till spent, when a new call was made, then from each halting-place visits to points of interest, examination, discussion, demonstration, and home to dinner. Among the illustrations in the book are excellent portraits of some of his more intimate friends, most of whom at one time or another accompanied him on his geological excursions. He had for forty years to give most of his time and attention to business, but all his hours of leisure were spent and all his recreation taken in the pursuit of his favourite subject geology. In his reply to the remarks which Sir Henry De la NO. 1551, VOL. 60] Beche made on presenting the Wollaston medal to him in 1849, he said : “Tt is true that I entered upon this field as a student and for relaxation, but the interest and difficulties of the subject speedily induced me to take it up with more earnestness and determination, and eventually led me to extend the inquiry over an area which I, at first, never contemplated. “The Tertiary geology of the neighbourhood of London may be wanting in beauty of stratigraphical exhibition and in perfect preservation of organic types, but in many of the higher questions of pure geology—in clear evidence of remarkable physical changes, in curious and diversified paleontological data, however defaced the inscriptions, which is after all but a secondary point—few departments of geology offer, I think, greater attractions. “The pleasure I have derived from the study of the remarkable phenomena which have come before me in the course of the investigation has far outbalanced the few obstacles I have had to contend against. I, in fact, feel deeply indebted to geology, as a source of healthful recreation, as an inestimable relief and abstraction in due season from the cares frequently attendant upon the active duties of life, for its kindly and valued asscciations, and above all for the high communing into which it con- stantly brings us in the contemplation of some of the most beautiful and wonderful works of the creation” (p 66). Yet most of his work, undertaken and carried on in the true scientific spirit, bore directly, as it turned out, on questions of the greatest economic importance. This was, however, by accident, for he studied the Coal Measures in early life only because his holidays were spent at Broseley, where he got interested in the geology of Coalbrook Dale. And similarly the Tertiary and Cretaceous rocks of the London district offered in later life the most accessible sections, and so he plunged with his usual zeal into their discrimination and classification with no ulterior view to the practical application of the information he was then acquiring. But the knowledge which he gained of the characters and sequence of both these groups of formations was afterwards of immense value to the country, and we find him not only a member of the Coal Commission, but also one of the most trusted authorities on water-bearing strata. His paper on Coalbrook Dale is a masterly sketch in which the fossils of different horizons are distinguished and the stratigraphical structure of the district is worked out with great accuracy and well illustrated by maps and sections. To give an idea of his work on the Tertiary strata would be to give a sketch of Tertiary geology which is not wanted in a notice of this kind, for he established the classification which is now adopted with very slight modification. He followed up the strata to the newest beds, and soon took part in the discussions which arose respecting the age and origin of the Glacial and post-Glacial deposits —controversies not yet settled, and inquiries out of which suggestions of new difficulties yet to be explained still continue to arise. It is very interesting to follow the progress of opinion respecting the association of the remains of man with those of extinct animals in the river gravels, whose antiquity was further proved by their relation to. the . N 266 NATURE [JuLy 20, 1899 physical geography of the country. There were doubts also as to the objects from the occurrence of which the presence of man was inferred, for, except in some very doubtful instances, it was not his bones that were found, but only flints roughly fashioned into serviceable instru- ments. A good sketch of the development of the inquiry appeared some years ago in Blackwood’s Magazine (vol. clvii., June 1895, p. 939). M. Boucher de Perthes had conceived the idea that so it must be, but it was long before he found sufficiently convincing evidence of the fact. At last, however, after Boucher de Perthes had been excavating, collecting, talking, and writing about it for years, Dr. Falconer visited him and acknowledged that a good prima facie case had been made out, and wrote to Prestwich to say that he ought to look into it. Prestwich accordingly made a pilgrimage to Abbeville, and came to the con- ) q [bs ~ = Fic. 4.—Romulus. ancestor of one of the parent species, though absent from the parents themselves. With regard to the zebra hybrids now under dis- cussion, the most striking point of difference in marking between “Romulus” and the other cross-bred foals on the one hand, and their common sire ‘‘ Matopo” on the other, is the multiplication of stripes in the former, and the tendency to the production of a gridiron pattern over the rump. The last-named of these characters re- sembles the condition seen in the mountain zebra, an earlier form, according to Prof. Ewart, than the Burchell group, while the former point recalls the still more ancestral pattern of the Somali zebra. In the Shetland pony’s hybrid, ‘“ Norette,” the pattern over the hind- quarters from the first resembled that of the Somali zebra ; in the other hybrids, the markings of the same region, indeterminate at first, finally settled down into a form suggestive rather of the less remote stage marked 274 NATURE [JuLy 20, 1899 by the mountain zebra. The difference in the general system of striping between “ Matopo ” and his offspring is well brought out in the figures here reproduced, by the | courtesy of the publishers, from Prof. Ewart’s work. A more special point, but one of great interest, is that ex- emplified in the accompanying figures of the brow-stripes in “ Matopo,” in “ Romulus,” and in a Somali zebra. The numerous rounded arches shown on the forehead of “Romulus” are very different from the four or five acutely pointed arches of “ Matopo,” and clearly bear a much greater resemblance to the corresponding pattern of the Somali zebra. It should, however, be mentioned that a system of brow-striping not unlike that of “ Romulus” occurs in Crawshay’s zebra, a member of the Burchell group. On one point of special importance the experiments have so far given results that, however interesting Fic. 5.—Somali Zebra. scientifically, are from the practical side disappointing. Following a suggestion of Captain Lugard, that zebra mules might possibly turn out to be immune to the disease communicated by the tsetse fly, and might thus help in solving some of the difficulties of African trans- port, Prof. Ewart, with great liberality, inoculated three of his hybrids with some of the tsetse organism at that time under investigation by Messrs. Blandford and Durham. The result of this experiment is not given in the present volume, but in the recently published Pvo- ceedings of the International Congress of Zoology at Cambridge it is stated that the inoculated animals, though apparently somewhat more resistant than horses, all died in about eight weeks. The above-mentioned are a few only of the points of interest brought out by the remarkable series of experi- NO. 1551, VOL. 60] ments dealt with in the present volume, but enough has. probably been said to show the importance of the problems which Prof. Ewart has set himself to solve, and the prospects of advance in knowledge which these researches hold out. It only remains to say a word in commendation of the general get-up of the book, and of | the character and accuracy of the illustrations, which in many cases are reproduced from actual photographs. _ The absence of an index or detailed table of contents is a drawback, but this, like the frequent repetition of the same facts, is perhaps inseparable from the method of publication adopted. A tabular list of the hybrids, giving their parentage and the more important features of their aspect, might be a useful addition, as the reader finds it a little difficult at present to piece together the various details, scattered through many parts of the work, under their proper headings. But any small defects of this kind will, no doubt, be completely remedied in the connected and systematic account of the fruit of his researches which Prof. Ewart leads us to hope for at some future time. Meanwhile, the course of his experiments will be watched with keen interest by all those who realise the import- ance, both scientific and practical, of a right con- ception of the laws of heredity. LANG JD), PIONEER CLIMBERS. OTWITHSTANDING what has been done by Coolidgeand Freshfield, by C. E. Mathews and F. Pollock, for the pioneers in mountain climbing, there is still room for a book so com- prehensive as that before us. Mr. Gribble has collected a quantity of interesting information, and prints at the end of his work several rare and curious documents. It is, moreover, not wholly restricted to the Alps, for it touches on early ascents in the Pyrenees and the Apennines. These, however, are distinctly subordinate ; the interest, as is only natural, centres on the moun- tain backbone of Europe. This is many-sided, but on the present occasfon we must restrict our- selves to aspects more or less scientific. A wide question is suggested at the outset : What caused that horror of mountains which was evidently so genuine among the chief nations of Europe till a period comparatively late in history? It was not felt by the Hebrew, as Mr. Gribble shows, but the Greek seems to have cared little for them, and the Roman detested them. Perhaps the practical nature of this people viewed them as an impediment to “imperial expansion,” a senti- ment hinted at in Napoleon’s question, ‘“‘ When will the Simplon be practicable for cannon?” Moreover, in Rome’s more luxurious days the ‘rough roads, hard fare, and bad lodging of a journey across the Alps would naturally be ob- jectionable. Classical influences, with a certain sympa- thetic similarity, may have caused the dislike once so general among our own countrymen, which has only been changed during the last thirty or forty years. These have witnessed a revulsion of sentiment which, whatever be its cause, is certainly one of the remarkable features in the later part of the nineteenth century. But to pass from a general question to more particular topics, we can incidentally gather from this volume no bad idea of how some parts of scientific knowledge have advanced during the last four centuries. Prior to this epoch men knew little of science, and less of the mountains ; pioneers were few, and the history of climb- ing—except when there was no help for it—was almost By Gribble. Illustrated. 1 “The Francis Early Mountaineers.” (London : T. Fisher Unwin, 1899.) JuLy 20, 1899] NATURE 2795 a blank. A monk of Canterbury, who crossed the Great St. Bernard late in the twelfth century, piously prayed that none of his brethren might come into that place of torment, and till long after that, though Leonardo da Vinci set a better example, and pilgrimages even began Fic. 1.—John Tinner’s Dragon. to be made to the top of the Roche Melon, the Alps found few to praise them. Fancy invested them with super- stitious terrors, of which the legend of Pilatus is an apt example, but here and there we come on the track of a sceptical traveller. In the first rank of these forerunners of the modern man of science is Conrad Gesner, who laughed at those stories, and was a true lover of the mountains. His successor, Josias Simler, even describes, about the year 1574, the precautions to be taken i in crossing snowfields and glaciers, but the seventeenth century had begun before any careful note was taken of the latter. Then the fact of their motion was observed, and was communicated some years later, in 1669, to our own Royal Society ; but the first specu- lations as to its cause appear to have been published by J. J: Scheuchzer, a professor, like the two first-named, at Ziirich. Though evidently ill-adapted for mountain walking, he stuck bravely to it for some years at the beginning of the eighteenth century, and at last published two bulky volumes with num- erous illustrations. These, in many respects, are interesting as a picture of Switzerland long before the coming of the tourist. But his book testifies to other changes, for it is full of dragon stories, and gives us portraits everything which appears in print. But before long in De Luc and Bourrit, and lastly in the really great De Saussure, scientific mountain travel begins, and the new era may be said to dawn. Now science finds in the Alps | a workshop as well as a playground, and special memoirs | such as that on Mont Blanc, noticed in these columns on June 15 (p. 152), are becoming common. Yet it is only just over a century since the last volume of “ Voyages dans les Alpes” appeared. Many curious. illustrations, as we have intimated, are reproduced by Mr. Gribble, some indicating the strides which have been made in the representation of scenery, especially Alpine, during the last two centuries. The one given below was published about the year 1760, yet it bears little resemblance to nature, while some earlier than it are still more completely conventional. Incidentally the quotations in this volume throw light on the fauna of the Alps, showing, for instance, that bouquetin were common in districts from which they have long vanished. Indeed, odds and ends of curious lore abound in these pages ; so that we have to thank Mr. Gribble, not only for an amusing book, but also for a valuable addition to Alpine literature. ule BONNEY. BOWER-BIRDS SEE the year 1840, when Gould communicated to the Zoological Society an account of their extra- ordinary “runs,” as they are locally called, the Bower- Birds of Australia and Papua have always attracted a large share of interest on the part not only of ornithol- ogists but of students of the habits of animals. For in the construction of the “bowers” or “runs,” from which they take their name, these birds stand absolutely alone, although the “playgrounds” of the Argus pheasant are | comparable to the sinooth patches cleared in the jungle by one species of Bower-Bird. On such an interesting subject it is of the utmost importance to have as much definite information as possible at first hand, and we are therefore glad to welcome the paper on the Australian | representatives of the group, from the pen of an original (such as that now printed) of many a loathly worm which now finds no representative on land, whatever it may do in the sea. Scheuchzer, in fact, though a good mathematician and a keen observer of minerals, plants, and even glaciers, had no critical faculty. He represents a type of student not yet extinct—the man whose first care is for “the litera- ture of the subject,” and who attaches an equal value to NO. 1551, VOL. 60] 2,—Griiner's view of the Lower Grundelwald Glacier. observer—Mr. A. J. Campbell, of Melbourne—which appears in the last issue of the Proceedings of the Royal Physical Society of Edinburgh, special value attaching to this communication from the excellent photographs of | “runs” and nests with which it is illustrated. 2706 NATURE {JuLy 20, 1899 “runs” of | it may | The As there may be a lingering idea that the these birds have some connection with nesting, be well to state that this is altogether a mistake. nests, of which beautiful examples are figured by Mr. Campbell, present indeed no special features, being built at a height of from ten to fifteen feet above the ground, and usually containing at the proper season two, or sometimes three, eggs. These latter, however, cannot “Run” of Great Bower-Bird. L ster ’ a (nron the Proceedings of the Royal Physical Society of Edinburgh.) From a photograph taken in Western Austral fail to attract the collector by their porcelain-like polish and beautifully pencilled markings. Thanks to the energy of Australian ornithologists, the nests and eggs of most of the species are now known, although some are rare and difficult to find. as Among the more elaborate types of “runs” or “bowers,” the author figures those of the Satin Bower-Bird, the | NO. 1551, VOL. 60] Spotted Bower-Bird, the Great Bower-Bird, the Queens- land Bower-Bird, and the Regent Bird; the third of | these being herewith reproduced. The phetographs confirm previous Statements as to the two types of decoration employed in these bowers, the taste of the Satin Bower-Bird displaying itself in the selection of bright-coloured parrot-feathers, while the other species named prefer bones and shells. The Spotted Bower- Bird may be described as a col- lector of sheep’s bones (especially the vertebrae), whereas the Great Bower-Bird accumulates bleached shells. As is the case with the “Viscacherias” of the Argentine Pampas, in a Bower-Bird haunted country it is well to search the “runs” for any glittering objects, such as money or jewellery, which may have been lost in the neigh- bourhood. The amount of grass and sticks employed in some of these “bowers” js enormous, one structure being described as rang - ing trom four to six feet in height. In one respect Mr. Campbell does not agree with some writers, who have stated that the Cat. Birds (Aeluroedus) differ from other members of the group in that they build no bower, but con- tent themselves with clearing a space of ground. No such spaces have, however, according to our author, yet been observed : and it is suggested that the birds may merely play on some fallen log. On the other hand, the Tooth- billed Cat-Bird (Scoenopaeus) of North Queensland does undoubt- edly clear such spaces, upon which are laid at intervals a few leaves of one particular kind of tree. This represents the simplest type of “run,” the most complex being that of the Gardener-Bird (Am- blyornis) of New Guinea, which builds an orchid-covered hut, with a mossy lawn in front, ornamented with brilliant flowers and berries. As to the object of these strange structures, Mr. Campbell has no new suggestion to offer, and we may therefore conclude that he accepts the old ‘playground theory.” Reve: THE COSMIC ORIGIN OF MOLDAVITE. UCH attention has recently been devoted by Austrian and Bohemian geologists to the solution of an interesting question, that of the origin of those peculiar glassy bodies which are known col- lectively as moldavite or bouteillen- stein. It has been considered by some authors that these fragments are to be looked upon as representing the relics of prehistoric glass-manufacture; but, as recently noted in the columns of NATURE, Herr J. Bares has lately brought forward experimental proofs | to refute the theory of the artificial origin of molda- vite glass. Additional stimulus has been given to the study of this problem by the recent enunciation of a ia by Mr. H. H. Johnston. JuLy 20, 1899] new theory. that these glassy fragments bear strong analogy to meteorites, and that they are in reality, like the latter, aerolites. In support of this view, in addition to other arguments, he lays special stress on the nature of the peculiar, though varying, surface sculpture of bouteillen- stein, a sculpture not consistent with any theory of mechanical transport in water. ) ) has opposed this hypothesis of a cosmic origin, and brings forward arguments for its refutation. This author rather inclines towards the theory of an artificial origin ; but Bares, by experiments above referred to, applied a process of elimination to the various theories put forward for the terrestrial origin of the glass, and finally considered that of Dr. Suess to be most probably the correct one. cent contribution to the literature of this subject is a short paper brought before the Bohmische Kaiser Franz- Josefs Akademie (Prague) by J. N. Woldrich last December. An abstract of this appears in the Bulletin NET TOLLE Dr. F. E. Suess has expressed the opinion | A re- | 277, Pror. KLEIN proposes to spend two or three weeks in this country, so that, after the work of the Catalogue Conference is finished, he can have an opportunity of discussing, with our mathematicians and physicists, the plan and scope of the second part of the Zzcyklopidie der Mathematischen Wissenschaften, which deals with Applied Mathematics. The season for his Prof. Rzehak, however, | visit is in some respects unfortunate, as being a holiday time ; : ; . on the other hand, there is the advantage that those who are to be found at home will have plenty of leisure to devote to the discussion of the details of this great work. THE death is announced, at the age of eighty-seven years, of the Right Rev. Charles Graves, Lord Bishop of Limerick, who in 1843 was appointed Erasmus Smith professor of pure mathematics at Trinity College, Dublin. His published work appeared for the most part in Cre//e’s MJathematical Journal, | and many of his theorems are to be found in text-books on | | | geometry. In 1841 he edited a translation, with considerable ad- International (dated 1898) issued by the Academy, and | ditions, of Chasles’ ‘* Memoirs on Cones and Spherical Conics.” from the photographs illustrating that paper the accom- | He was elected Pcesident of the Royal Irish Academy in 1861, | and a Fellow of the Royal Society in 1$$o. panying figures have been selected for reproduction. Fic. 4. Herr Woldrich describes the surface markings of speci- mens in his own large collection, and points out the re- semblance between certain of these Bohemian examples and the peculiar obsidian-bombs from Australia, described by Stelzner. Some of the Bohemian occurrences show, in fact, a hollow, bomb-like form. A fragment of such a specimen is represented in Fig. 8a. Figs. 4 and 6, types of sculpture, Fig. 4 exhibiting “finger impressions,” and Fig. 6 a network of furrows, having in part a rough radial arrangement. The moldavite found both in northern and southern Bohemia occurs in sandy de- posits which are regarded as belonging to either late Tertiary or early Diluvial time. Herr Woldrich con- siders that the known facts relating to moldavite and its distribution speak in favour of its extra-terrestrial origin, but that it is only known to occur in sandy deposits, whether in Europe or on other parts of the earth’s surface, he regards as a striking circumstance. NOTES. AT a meeting of the Glasgow University Court held on the | 13th inst., Principal Story presiding, a petition for leave to retire from the chair of Natural Philosophy was presented from Lord Kelvin. The Court granted the leave asked, and accepted Lord Kelvin’s resignation with deep regret. A remit was made to the Principal to prepare a minute to be signed by all the | members of the Court, expressing their sense of the great loss that the University is now to sustain. Lord Kelvin has occupied the chair for fifty-three years. Dr. P. F. RAymonp, the successor of Prof. Charcot in the chair of Nervous Diseases at the Saltpétriére, has been elected a member of the Paris Academy of Medicine. NO. 1551, VOL. 60] Fic. 6. | THe death is announced in the d4¢henaeum of Dr. Eugen Ritter von Lommel, Rector of the University and a member of the Academy of Sciences of Munich. He was the author of several works, including ‘‘ Das Wesen des Lichts,” ‘* Wind und Wetter,” and ‘‘ Lexikon der Physik und Meteorologie.”” THE negotiations which for some time past have been carried photographed in natural size, show two characteristic | 0n between the Royal Geographical Society and the University of Oxford with a view to the establishment at Oxford of a fully- equipped school or institute of geography, for the use, not only of Oxford graduates and undergraduates, but of others who desire to avail themselves of such an opportunity, have come to a satisfactory conclusion, and the school will begin operations in October next, under the direction of Mr. H. J. Mackinder. The Royal Geographical Society is to contribute 400/, annually for five years out of the 800/. required, and the school will be under the supervision of'a joint committee of representatives of the Society and the University. At a recent meeting of the | committee, the staff was appointed, Mr. Mackinder being the | head of the school, and dealing specially with historical | geography ; Mr. A. J. Herbertson has been appointed assistant to the Reader, and will deal with physical geography, carto- | graphy, and surveying; Mr. H. N. Dickson has been ap- | pointed Lecturer on Physical Geography; and Mr. G. B. Grundy will in 1899-1900 lecture on ancient geography. The | work of the school will include a course of systematic instruc- tion primarily intended for graduates and other advanced students, with classes, demonstrations, and practical work in physical geography, cartography, and surveying. Courses of lectures will also be given with special reference to the his- torical and scientific teaching of the University The work will be carried on for five days each week during term. The lecture-room and laboratory will be in the Old Ashmolean 278 Museum, the upper floor of which is being fitted with the necessary appliances. . PartTicuLars have reached us of the autumn meeting of the Iron and Steel Institute, which, as has already been announced in NaTurg, is to be held in Manchester from August 15 to 18 next. The following papers have been promised for reading :— On the constitution of steel, by Prof. E. D. Campbell; on dif- fusion in steel, by F. W. Iarbord and Thomas Twynam ; on the magnetic concentration of iron ore, by H. C. McNeill; on India as a centre for steel manufacture, by Major R. H. Mahon, R.A. ; on pig iron fractures and their value in foundry practice, by J. W. Miller ; on practical microscopic analysis for use in the steel industries, by C. H. Ridsdale; on the relation between the structure of steel and its thermal and mechanical treatment, by Albert Sauveur ; on the present position of the solution theory of carburised iron, by Dr. A. Stansfield ; on the iron industry in the territory of his Highness the Nizam, by Shamsul Ulama Syed Ali Bilgrami; on a new casting machine for blast furnaces, by R. Hanbury Wainford ; on the utilisation of powdered iron ore, by Prof. J. Wiborgh. In the outline programme, just issued, full particulars are given of a number of excursions for which arrangements have been made, THE summer meeting of the Institution of Naval Architects, which is taking place this week at Newcastle-upon-Tyne, was opened on Tuesday, when papers were read by Sir Andrew Noble (on “* The Rise and Progress of Rifled Naval Artillery’), Dr. F. Elgar (on ‘* The Distribution of Pressure over the Bottom of a Ship in Dock, and over the Dock Blocks’’), and Mr. Nelson Foley (on ‘‘ A New System of Forced Draught”). A CONFERENCE was held at the Home Office on Tuesday with some of the principal pottery manufacturers, in reference to the report by Prof. T. E. Thorpe and Dr. T. Oliver on the employment of compounds of lead in the manufacture of pottery. Science states that a laboratory for the physical analysis of soils has been established by the Maryland Geological Survey. A full outfit of apparatus has been installed, and work will be engaged in during the coming year upon the soils of Maryland, in conjunction with the geological surveying of the same area. The Survey has also recently had constructed an elaborate calorimeter for the determination of the calorific power of coal, preparatory to the investigations of the coal formations of Maryland, an exhaustive report on which is promised for an early date. THE Magnetic Observatory at Vienna having had to be dis- continued in consequence of the electric tramways and electric light wires, Prof. Pernter has submitted to the Austrian Govern- ment a plan for a new observatory to be situated at some distance from Vienna, and to be provided with instruments of the latest construction. ACCORDING to the Pharmaceutical Journal, a committee has been formed in France to organise a public subscription in aid of scientific research, with a view to the discovery of new methods of treatment for infectious and contagious diseases. That the need is pressing will be seen when it is stated that France loses every year by these diseases two hundred and forty thousand victims, nearly double the number of lives lost in the Franco-Prussian war of 1870. Out of this total, tuberculosis is responsible for 100,000 deaths; typhoid fever and other con- tagious diseases, such as small-pox, measles, scarlatina, whooping-cough, diphtheria, and puerperal fever for 64,000, without speaking of the ravages caused at long intervals by cholera and plague. NO. 1551, VOL. 60] WAT ORE: [JuLy 20, 1899 THE committee appointed to inquire into the use of preserv- atives and colouring matters in food held their first meeting on Monday, when there were present Sir Herbert Maxwell, M.P. (in the chair), Dr. Timbrell Bulstrode, Dr. Tunnicliffe, and Mr. C. J. Huddart (secretary), The terms of reference to the committee were under discussion, and certain preliminary matters were disposed of, a second meeting being fixed for early in August to complete arrangements for the carrying out during the hot weather of necessary experiments in relation to the use of preservatives and colouring matters in one and another class of food, and to settle the scope of the evidence to be taken when the committee reassemble in October next. THE Liverpool expedition for the study of malaria in Sierra Leone, to which attention has already been called in thesecolumns, will sail on July 29. In addition to Major Ross and Dr. Annett, each of the Liverpool School of Tropical Diseases, the ex- pedition will include Mr. E. E. Austen, of the British Museum (Natural History), and Dr. S. Van Neck, official delegate of the Belgian Government. The School of Tropical Diseases has recently been in communication with the various Government departments concerned with regard to the forthcoming research, On July 1 the Colonial Office wrote that Mr. Chamberlain had learned with great satisfaction that the expedition of the Liver- pool School was being sent, and that he appreciated the energy and public spirit shown by the Committee of the School in the matter. Mr. Chamberlain also stated that the local authorities at Sierra Leone will be instructed to give every facility to the work of the expedition. TuE Vienna correspondent of the Zz#es, telegraphing to that paper on July 14, says the renewed experiments by Prof. Tuma and a number of officers of the Vienna garrison to test the possibility of wireless telegraphy between two balloons were attended with a certain degree of success. A balloon held captive at a height of 150 metres served in place of the mast used in the Marconi experiments, being connected with the despatching instruments on the ground by a copper wire. The second free balloon carried a receiving instrument and a wire which hung loose 20 metres below the car. In these conditions it was found possible to communicate with the three officers in the free balloon, who signalled with flags that they had received and understood the telegraphic messages. These signals were observed at an estimated height of 1600 metres and a distance of about 10 kilometres from the despatching station. Owing to the size and weight of the accumulators and the great danger of bringing them into close proximity to a large volume of explosive gas, it is thus far impossible to telegraph from a balloon to the ground or from one balloon to another. On the return of the officers to Vienna a comparison will be made between the detailed particulars noted by them and the report of the actual messages despatched. THE Liverpool Section of the Society of Chemical Industry proposes, with the approval of the Council, to perpetuate the memory of the late Dr. Ferdinand Hurter, especially his great services to applied chemistry, by instituting a memorial lecture to be given every second year on some subject connected with applied chemistry. The lecturer will be chosen by the Liver- pool Section of the Society, and it is proposed to collect a sum of 300/., which it is supposed will be sufficient for the endowment. ON the afternoon of Saturday, July 8, a marble bust of the late Prof. William Rutherford, F.R.S., was unveiled in: the Physiology ‘Class-room of the University of Edinburgh by Principal Sir William Muir, in the presence of, among others, Sir William Turner, Prof, T. R. Fraser, Prof. Crum Brown, Prof. Hunter Stewart, Dr. Clouston, and Dr. E. W. W. Carlier. The Lord Provost of Edinburgh and Prof. Schafer sent apologies for absence. The bust, which is by Mr. John Hutchinson, was JuLy 20, 1899] NATURE 279 subscribed for by past and present members of the class of physiology. It bears the following inscription on the pedestal: —In piam memoriam Gulielmi Rutherford, M.D., F.R.S., in Universitate Academica Edinburgensi, ab anno MDCCCLXXIV. ad annum MDCCCXCIX., Physiologic Professoris hanc effigiem posuerunt discipuli eius Universitatis huius cives. A.D. MDCCCXCIX.” Sir Joun WoLFreE Barry, K.C.B., F.R.S., has been elected by the Council of the Society of Arts chairman for the ensuing year. Tue fourth International Congress of Psychology will be held in Paris from August 20-25, 1900. The organisation is left to the French members, and the following are the officers : President, Th. Ribot, professor of experimental and comparative psychology in the Collége de France ; Vice-President, Charles Richet, professor of physiology in the Paris Faculty of Medicine; General Secretary, Pierre Janet, Director of the Laboratory of Psychology in the College de France. The seven Sections and the Presidents are as follows: (1) Psychology in its relations to physiology and anatomy, Prof. Matthias Duval; (2) Intro- spective psychology and its relations to philosophy, Prof. G. Séailles; (3) Experimental psychology and _psycho-physics, M A. Binet ; (4) Pathological psychology and psychiatrie, Dr. Magnan; (5) Psychology of hypnotism and related questions, Dr. Bernheim ; (6) Social and criminal psychology, M. Tarde ; (7) Comparative psychology and anthropology, Prof. Yves Delage. Those wishing to attend the congress should apply to the Secretary, and those wishing to present papers should forward abstracts not later than January I next. A COMBINED meeting of the German and Viennese Anthropo- logical Societies is to be held at Lindau from September 4 to 7 of the present year. AN expedition to determine the geological and mineralogical features of the almost unknown region lying between Buffalo Hump, in Idaho County, Idaho, and the Nez Perce Pass, in the Bitter Root range, has been organised and equipped by Colonel W. S. Brackett, of Peoria, Ill. The party numbers twelve men, all of whom are stated to be experienced mountaineers. Reports from Vancouver, British Columbia, announce the ascent for the first time of Mount Morrison, the highest moun- tain in Formosa, by Stoepel, the explorer of the Pic of Orizaba n Mexico. Dr. D. J. LEECH, professor of materia medica and thera- peutics at the Owens College, Manchester, will deliver the address inaugurating the winter session of the Pharmaceutical Society on October 2, and on the occasion the Society’s Hanbury medal will be presented to Prof. Albert Ladenburg, of Breslau, for his researches into the chemistry of the atropine alkaloids. Tue ‘‘ Board of Estimate and Appointment” for the City of New York has set aside 63,000 dollars for the zoological garden in Bronx Park. It is also proposed to raise the appropriation for the American Museum of Natural History from 90,000 to 130,000 dollars annually. AN appeal has recently been made in the Manchester press, by the President and Secretary of the Manchester Literary and Philosophical Society, for help in restoring the tomb of Dalton the chemist. The appeal is made ‘‘ to those residents of Man- chester, chemists and others, who are interested in the work and fame of John Dalton.” It appears that the funds of the Society cannot be used for the purpose, but the Council ‘* have felt that the continued neglect of the resting-place of one of Manchester’s greatest worthies would be a scandal and a dis- credit.” The sum of 75/. in all is the amount endeavoured to NO. 1551, VOL. 60] be raised, it being thought that the interest on the sum remaining after the payment of present repairs has been made will suffice for keeping the tomb in repair. Mr. GRIESBACH states in the annual report of the Geological Department of India that last year a find of copper and gold was reported near the village of Rohera, a station on the Rajputana-Malwa Railway, in Sirohi territory. The place had evidently been worked for copper in ancient times, and to a considerable extent, as may be seen from the heaps of copper slag in the vicinity. The old mine had, however, not been sufficiently excavated at the time of the Director's visit to enable him to judge of the extent of the deposit. A CONSIDERABLE amount of attention has, says the Journal of the Society ef Arts, been given in France to what may be termed general agricultural education. Agricultural teaching, of a more or less rudimentary order, has been made obligatory at elementary schools, and a small garden for practical illus- tration has been attached to many of these institutions in rural districts, “and the instruction thus given has, it is said, produced most beneficial results. The general instruction is given by departmental professors and special professors, whose duties may be divided into two distinct sections: (1) general instruction of adults—in the service of the Ministry of Agri- culture ; (2) teaching in the normal schools—in the service of the Ministry of Public Instruction. The tuition for adults takes the form of lectures, delivered in different parts of the department. The lectures are intended to enlighten landed proprietors, farmers, and others as to the best agricultural methods, the applications which can be made of scientific discoveries, &c. ; in a word, to assist them in reaping the greatest possible profit from their land. The subjects treated naturally vary greatly according to the needs of the population of each department ; the lectures, however, possess one charac- teristic in common, they are of an essentially ‘‘ popular” type. The lecturer also, at the close of each lecture, places himself at the disposal of his audience, with the object of advising them individually regarding special questions, and of elucid- ating any points touched upon in his discourse which they may have failed to grasp. The most powerful aids to this class of teaching are found in the ‘‘ experimental” and *‘ demon- stration” fields. Attention is also called to the agricultural stations and laboratories of the country, which, though not properly coming within the sphere of educational establish- ments, render considerable service to the agricultural popu- lation. AccoRDING to the Watzonal Geographic Magazine, forecasts for forty-eight hours in advance, for all States east of the Rocky Mountains, were, for the first time in the history of the Weather Bureau, regularly issued from Washington each night during April of the present year. Orbers issued by the Government of India to civil surgeons with entomological proclivities require them ‘‘ to make collec- tions of mosquitoes and other flies that bite men or animals, in accordance with the instructions contained in [rof. Ray Lankester’s pamphlet,” with a view of determining the possible connection of malaria with mosquitoes. For the general de- tructions of mosquitoes several methods have, says the Indian correspondent of the Zance¢, been tried. In many places the engineer has been successful by draining the marshy areas. In others the use of kerosene by throwing it into the water where it forms a film on the surface has prevented the developing larve from reaching the air, and has thus brought about their destruction. A more recent experiment has been the employ- ment of permanganate of potash, which is said to kill the insect in all stages of its development. As this chemical has also been 280 NATURE [JuLy 20, 189y largely employed for purifying the water of doubtful wells, and especially with the view of protecting against the cholera _ bacillus, it would seem particularly applicable for use in India. Tue Times of Monday published a very interesting account of a visit paid by Dr. Karl Peters last April to some ruins near the river Muira, a southern tributary of the Zambesi, in Portuguese territory, nearly opposite Shupanga. The ex- plorer made his journey in consequence of a passage in the Atlas Historique, which is to the effect that half a day’s journey from the river Mansoro is the fort of Massapa, and near this is the great mountain of Fura, very rich in gold, in which are Cyclopean ruins. It was to find these ruins that Dr. Peters, accompanied by Mr. Leonard Puzey and Mr. Ernest Gramann, journeyed from the Zambesi. After recounting in- cidents of the journey, the writer says the decisive discovery for the exploration was made by Mr. Puzey on April 20. The ruins are situated on the hill which runs parallel to Mount Peters, and are about two miles distant from Inja-ka- Fura. Dr. Peters’ description of his discovery is as follows: ““We discovered . . . another ground-wall which had un- doubtedly been a part of a building, maybe a temple, maybe a storehouse. _ This wall had been worked into the natural rock, which here forms a sort of flat floor. The stones of this ground- wall, samples of which I have sent to London, are heart-shaped, and are worked with a pick, so that the description in our old report saying the stones were not worked with a pick apparently only applies to the outer walls. Perhaps the author never took the trouble to visit one of the ruins. I laid bare a part of this ground-wall on the top, but gave up further digging because I was afraid that my clumsy workmen might do harm to the remains. They have, indeed, already destroyed part of the ground-wall. The stones of the wall are a pseudomorph sand- stone, while the rock into which they are worked is quartzitic slate. The whole of the ruin is built after the general ancient Semitic pattern. The Cyclopean wall skirts the hill about half- way between the bottom and the top; on the top the buildings, the hoarding-place, and likely the temple were standing. The remains of a ground-wall along the edge of the top lead me to believe that a second wall formerly ran round the platform itself. To explore the ruin properly it will be necessary to send a scientific expedition witha proper outfit for such excavations. The débris have to be removed, and this I am sure will take a considerable time. Why the old conquerors chose this spot for their fort is easy to see. The Muira touches the bottom of the hill, so water was handy. A second river we have discovered at the back of the ruin. From the top they had an outlook over the wide plain before them, while they had the bulk of the Fura From their fort they commanded the plain as well asthe mountain. I have called the hill on which the ruin stands after its discoverer ‘ Puzey Hill.’ Mr. Puzey some days later found a second ruin west-north-west of the first on another head of the same ridge looking over the plain in the same direction. Iam certain we shall find still more of these Cyclopzan buildings when our time, which now is otherwise occupied, permits of a more extended exploration.” massive at their back. THE British Central Africa Gazetle for May 24, which has just reached us, says ‘‘ from time to time it has been rumoured that giraffes existed in British Central Africa, on the Loangwa River, but, although that river valley has been frequently visited during the last ten years by Europeans, no authentic inform- ation on the point has ever been obtained. Last month, how- ever, a giraffe was shot on the east bank of the Loangwa in the Marimba district by a European prospector, and its skin (in- complete) sent in to Captain Chichester in Mpezeni’s country. The hinder half of the skin is being sent to the British Museum, and it is hoped that a complete specimen may be now obtained. NO. 1551, VOL. 60] The existence of giraffe in Marimba is remarkable: the area in which they are found is extremely restricted, and their number appears to be very few. The one shot, however, was in a herd of about thirty-five. The nearest country north of Marimba in which giraffe are known to exist is north of Mareres, where the Elton-Cotterill Expedition met with them (many years ago). To the south, Matabeleland is the nearest giraffe country.”” THE same number of the Gaze¢¢e states that there seems to be no further decrease in the number of elephants still existing in the Protectorate ; indeed, the natives round about Domwe have been complaining to the Acting Collector of the damage done in their food plantations by these animals. In the Johns Hopkins University Czvcz/ars for June 1899 a number of notes from the physical laboratory are published under the editorship of Prof. Joseph S. Ames. These com- prise a short paper on the effect of temperature, pressure, and used solutions on the deposit of silver voltameters, by J. F. Merrill; notes on the energy-spectrum of a black body, and on the absorption of ice in the ultra-red, by F. A. Saunders; on the Zeeman effect, by H. M. Reese; on electric absorption in condensers, by L. M. Potts; on transference of heat in cooled metals, and on a method of measuring the frequency of alter- nating currents, by Carl Kinsley. A list of publications in the department of physics, by those who are now or who have been members of the University, is appended. This list, which re- presents roughly a year’s work, occupies three columns, and in- cludes over ninety works and papers by sixty authors. Similar notes and lists from the department of history and politics also appear in the same number, under the editorship of Prof. Herbert B. Adams. THE Berichte der Naturforschenden Gesellschaft of Freiburg (Baden) contains several papers of interest to physicists. Kathode and Réntgen rays form the subject of a discourse by L. Zehnder, who deals somewhat fully with the theory of fluorescence ; Prof. F. Himstedt describes apparatus for illus- trating lecture experiments on Hertzian waves and on Marconi’s telegraphy, and also writes on point-discharges in high-frequency currents. Of biological interest in the same number are Prof. G. Steinmann’s notes on the formation of dark pigment in mollusca, and on Soueina—a genus of fossil algee, and August Griiber’s note on green Ammoebae. A Goop work is being done in Italy by the ‘‘ Valle di Pompei,” an institution in the province of Naples for rescuing and educating the children of prisoners and criminals. Apart from the philanthropic aspect of this undertaking, the Refort contains statistics of interest to anthropologists, criminologists, and those who make a study of heredity. It would appear that under the salutary influence of their environment the children of the worst criminals often take a prominent place in the matter of good conduct and diligence. THE U.S. Weather Bureau has issued a very useful pamphlet (Bulletin No. 26) entitled ‘‘ Lightning and the electricity of the air,” by A. G. McAdie and A. J. Henry. The work is divided into two parts: Part 1 deals with the electrification of the atmosphere and the best methods of protecting life and property from lightning, being to a large extent a revision of Bulletin No. t5—*‘ Protection from lightning.” Part 2 gives statistics of actual losses of life and property sustained in the United States during 1898. The principal facts of the paper are drawn from articles by the authors in various magazines, with the object of furnishing information of practical value generally, especially to those who may have occasion to seek protection from lightning. The work contains interesting par- tculars relating to the electrical potential of the upper air, as manifested by kite experiments and auroral displays. Jury 20, 1899] NATURE 281 Tue Pilot Chart of the North Atlantic Ocean for July, issued by the Hydrographic Office of Washington, contains an article on tropical cyclonic storms or West India hurricanes which are prevalent at this season of the year. Froma table showing the number of storms experienced between 1885 and 1898, it is seen that the greater number occur between August and October. The nature and mean path of the hurricanes are exhibited by a diagram. In its earlier stages, the centre of the path of the storm has a certain amount of westing, due to the general west- ward motion of the atmosphere in the low latitudes in which the storm originates, and the whirl is small, probably less than 100 miles in diameter, but its growth is rapid, so that in the middle and higher latitudes it may attain a diameter of 500 or even 1000 miles. The velocity of progression along the track of the disturbance reaches from twenty to thirty miles an hour in high latitudes, while the velocity of the whirl itself, in a direction against the hands of a watch, attains the force of a hurricane. Tue interesting ani useful ‘‘Glossary of Popular Local and Old-fashioned Names of British Birds” contained in “* A Dictionary of Bird Notes,” by Mr. Charles Louis Hett, has been issued separately by Jackson, of Brigg. THE additions to the Zoological Society’s Gardens during the past week include a Bonnet Monkey (A/acacus sznicus, 8 ) from India, presented by Miss Nesta Bevan; a Black-faced Spider Monkey (Af¢e/es ater) from Eastern Peru, presented by Mrs. K. E. Mackenzie ; two Campbell’s Monkeys (Cercopithecus camp- Sellé, 6 9) from West Africa, presented by Captain F. R. B. ‘Parmeter ; a Mozambique Monkey (Cercopithecus pygerythrus) from East Africa, an Arabian Gazelle (Gazella arabica) from Arabia, presented by Mr. B. T. Ffinch; two Common Foxes {Canis vulpes) from Russia, presented by Mr. A. H. Britten ; an Arctic Fox (Canis /agopus) from Iceland, presented by Mr. M. Magnusson; five Common Hedgehogs(Z7znaceus europaeus), European, presented by Mr. Geo. Long; three Chipping Squirrels (Zwmzas striatus) from North America, presented by the Rev. A. E. Tollemache; a Common Peafowl (Pavo cres- ¢atus, 3) from India, presented by Miss A. S. Heldmann ; two Climbing Anabas (Anadbas scandens) from India, presented by Mr. P. Barford ; two Rheas (Rhea americana, white var.) from Argentina, two Syrian Bulbuls (Pycvovzotus xanthopygos) from Syria, an European Pond Tortoise (Zzys orbiculare), European, deposited; two Rose-coloured Pastors (Pastor rvoseus), two indian Mynahs (Acridotheres ginginianus) from India, two Bamboo Partridges (Bambustcola thoracica) from Northern China, two Lunulated Honey-eaters (J/edithreptes lunulatus), two Pied Grallinas (Gallina australis), two Musky Lorikeets (Glossopsittacus concinnus) from Australia, purchased; a Japanese Deer (Cervus stka, 9), born in the Gardens. OUR ASTRONOMICAL COLUMN. TeMreL’s Comer 1899 c (1873 II.). phemerts for 12h. Paris Mean Time. 1899. R.A. Decl. Br. oem. os. Aes i July 20 20 39 34°3 —18 4 26 3°570 21 40 461 18 37 9 22 Ate57-0) ... - 19) Loped! 23 43) 1955... - 19 4319 3662 24 AAL2tT ... , 20) 16822 25 45 326 ... 20 49 38 200 ee 40 44°0 ... 21 22 55 27 «-. 20 47 554 —21 56 9 3698 Hormes’ Comer 1899 d (1892 III.).—Prof. C. D. Perrine gives full details of his rediscovery of the comet in Asér. Fournal, No. 465. It was found with the 36-inch refractor, NO. 1551, VOL. 60] using a power of 270. It appeared as a round nebulous mass about 30” in diameter, with only a slight brightening at the centre. The conditions were good, the sky being very clear and the star images steady. The object was very faint, not brighter than 16 mag., and very difficult to observe, so that the probable error of observation of its place was larger than usual. DyNAMICAL THEORY OF NEBUL.—In No. 465 of the Astronomical Journal, Dr. E. J. Wilczynski gives an extended explanation of a dynamical theory of ring and spiral nebulz which he first brought forward in 1896 (As/70.-Phys. Journad, vol. iv. p. 97, 1896). He starts with the assumption that the primordial nebula exists either as an assemblage of meteorites or as a gaseous mass obeying the laws of hydrodynamics. Then, in some unexplained way, each particle is to describe a circular orbit about the common centre of gravity, at which point there may or may not be a condensation. Such an arrangement is not necessarily stable, the limit depending on the relative ratios of the masses and distances of the individual particles, and the ratio of the mass of the central controlling body to its distance from the swarm. If these conditions allow stability the body may condense to a star, single or double. If the system be unstable, however, then on applying Kepler’s third law to the revolving particles it is found that the inner members, owing to their greater angular velocity, constantly advance with respect to the outer ones, and after an interval the particles originally lying along a vadéus of the swarm will be drawn out into a spiral curve, as is actually the case in the bodies known as spiral nebulee. According to this view, the age of a nebula would be to some extent indicated by the zzber of tts corls, and the author gives an interesting suggestion that this might be investigated by a minute comparative examination of all photographs of spiral nebulee of different dates. The paper concludes by indicating the possibility of determining the /azw of rotation of these bodies by a combination of spectroscopic and photometric observations. THE NATAL OBSERVATORY.—The annual report of Mr. E. Nevil, Government Astronomer of the Natal Observatory at Durban, consists chiefly of the detailed meteorological observ- ations made at the institution. The staff consists of the director, one senior astronomical assistant, one junior astronomical as- sistant, and one meteorological assistant. The astronomical equipment includes an 8-inch Grubb equatorial refractor, a 3-inch Troughton and Simms transit instrument, sidereal and mean time clocks, 3-inch portable equatorial refractor, and an automatic signal transmitter and recorder. Owing to a reduc- tion in the vote to the observatory, much of the work has had to be put aside. The system of time signals established over the Colony has been carried on without alteration, this being facilitated by the erection of new wires. Since the appointment of the astronomer in 1882 there has been no official residence, the computations, &ce., having been mostly made in the open air. This is at last to be remedied by the erection of a residence, all the fixtures, water supply, &c., however, being provided by the astronomer himself. TEMPERATURE CHANGES IN YERKES OBJECT-GLASS.— Prof. Barnard has several times made series of measures with the large telescope to find if the changes produced in the instrument by variations in temperature were of sufficient amount to necessitate their consideration in delicate invest- igations. During the last year observations have been made of the focus at temperatures varying from — 22° F. to +80° F., the range thus being 102° (Astr. Journal, No. 462). The means of the observations made on nineteen nights show a marked difference in the focus, and it was found that the object-glass shortened 0°26 inch more than the steel tube which carried it. Micrometric measures of the difference in declin- ation between the stars 4¢/us and Pezone of the Pleiades showed a decrease of nearly 0:2 (from 0”°676 during July- September to 0”"491 during January-February). From the result of these experiments Prof. Barnard thinks that for exact work, such as parallax, with a large glass in a variable climate, these minute changes ought to be deter- mined and taken into account. In addition to these visual observations, careful determin- ations of the changes in the colour-curve during wide extremes of temperature are being carried on by Prof. Frost and Mr. Ellerman. 282 NATURE [JuLy 20, 1899 ELECTRIC ARC) ISSING is one of the few phenomena connected with the electric arc with which every one is more or less familiar. In the old days the sudden, almost complete, extinction of the light of an arc-lamp, and the loud hiss accompanying its relighting, was socommon an occurrence that it was supposed by the lay mind to form part and parcel of the working of the — ““ electric light,” and led to a lively prejudice against that light on the part of the public. In these days of .enclosed arcs and | of better constructed lamps, such little interludes are of far less | frequent occurrence ; but it is as important as ever, from a scientific point of view, to discover their origin, and even from the practical side anything which points to a remedy for this | grave defect in arc-lighting cannot fail to be of interest. | The object of the present article is to explain the cause of | hissing in direct current open arcs; that is to say, in arcs in which the current flows always in one direction, and to which | the air has free access at every point. | { THE REASON FOR THE HISSING OF bi) | a sound something like that of steam under pressure, issuing from a pipe. This sound is accompanied by a diminution of about ten volts in the P.D., or electric pressure between the carbons, and an increase in the current. For the experiments on which the present article was based, three sets of electrical measurements were made, viz. measure- ments of the current, the P.D. between the carbons, and the length of the arc. Before each observation was made the current and length of are were kept 7%gorvozs/y constant for a sufficient length of time for the carbons to take their character- istic shape for that particular current and length of arc, and long enough, therefore, for the P.D. to have become constant also. Such an arc is called a zovmal arc, as contrasted with one arrived at in a haphazard fashion by suddenly giving the current some particular value and the arc some particular length, and making observations without allowing time for the carbons to acquire their proper forms. The carbons used were generally both so/d, that is, neither had a soft core such as is usually given to the positive carbon when the arc is employed for lighting purposes, and they were, OPEN ARCS. Sotia Carvors 7 re ] ~ i NX is) is S) Qo Ss iS) Ss PD between carbons in Volts. ay G l es ( en i 2 USS SPN | ah sito ‘ Teale ose | 40} kl WC Arcs. | Le | Me \ aan 7 a \ N ° | | \ \ as 35 en — ———— + a Ne eS 4 + asl + | NM is G » | PyAl eee L Ger Ee [eta pa eee Oo: a 4 6 8 /0 12 /4 /6 18 20 22 rae 26 28 30 Current in Amperes. Fic. 1.—Curves connecting P.D. and Current for Constant Length of Are. Carbons :—Positive, 11 mm. ; Negative, 9 mm. There are other ways in which a change taking place in the arc may manifest itself, in addition to giving out sounds of various kinds or by becoming silent. For example, there may be changes in its electrical measurements, or an alteration in the appearance of the crater, the arc, and the carbons. The sounds given out by the direct current open arc are many and various, but only two seem to possess much significance — the hum and the hiss—and the causes of these are evidently connected with one another, for the hum never occurs except when the arc is on the point of hissing or has just been hissing, although it is quite possible to make an arc hiss and become aie again without any hum being heard either before or alter. The hum is a distinct musical note, which is often quite low to start with, and gets higher and higher, till it finally rises to a shriek, and then the arc breaks into a loud hiss, giving forth 1 Based on a paper read before the Institution of Electrical Engineers by Mrs. W. E. Ayrton. NO. 1551, VOL. 60] as usual, placed vertically over one another with the positive carbon on top. Some of the results of these experiments are given in Fig. 1, in which the curves connect the P.D. between the carbons with the current, for various constant lengths of arc. Starting from the left, each curye goes smoothly on its way, as the current increases, till a certain point is reached, when it suddenly breaks down, and is continued in a straight line far below and to the right of its own lowest point.. The break-down occurs when the current has such a value that the arc can no longer remain silent. The dotted lines, which join the cwsves for silent arcs to the strazght /énes for hissing arcs of the same length, indicate ranges of current that will not flow through the par- ticular length of arc indicated at all if the arc is normal with the arrangement of the circuit existing when the experiments were made. An examination of these curves shows that with the carbons used, and with the xorvma/arc, the following results are met with: JuLy 20, 1899] NATURE 283 (1) When the length of the arc is constant and the arc is silent, it may be made to hiss by increasing the current sufficiently. (5) For the hissing arc the P. D. is constant for a given length of arc, whatever the current. It was Niaudet (La Lumiére Electrique, 1881, vol. ili. p. 287) OPEN ARCS. Positive Carbon Cored. - ee ape fal oie wn °o + or a a ; \ | ea | PD. between Cartons in Volts. © o O +o) iF + 3 ie [ | 0) TOY TO fo) , “2 ; ee tno Pe ee | ee 30 . ‘. my Sis . . . D oO ; : eT SSIEENG ———=_== ae 5 ;. o Sess Soh s sats suis a 10 12 14 16 18 20 22 24 26 28 30 32 34 Current tn Amiperes. Fic. 2.—Curves connecting P.D. and Current for Constant Lengths of Arc. Carbons :—Positive, 9 mm. Cored. ; Negative, 8 mm. Solid. (2) When the current is constant and the arc is silent, shortening the are will make it hiss. (3) The largest current that will maintain a sz/ez¢ arc is greater the longer the arc. who, in 1881, first observed the fall of about 10 volts in the P.D. between the carbons at the moment hissing began, and, although perhaps there is even yet a lingering notion that it is only when an arc is short that it can hiss, I find that as far back OPEN ARCS. Positive Carbon Cored. SS A & mm 5 mm 4m 5am — { 2mm | Hissing Unstable State! \ mm. LN Se mm . fs 1 | { 15 * 20 25 30 35 40 Current in Amperes. . Fic. 3.—Curves connecting P.D and Current for Constant Lengths of Arc Carbons :—Positive, 18 mm. Cored. ; Negative, 15 mm. Solid. t (4) When the arc begins to hiss, the P.D. suddenly falls | as 1889 Luggin (Wen Sztzungsberichte, 1889, vol, xlvii. p- 118) about ro volts and the current suddenly rises two or three | showed that, however long an arc might be, it would still hiss amperes. NO. 1551, VOL. 60] were the current increased sufficiently. 284 NATURE [JuLy 20, 1899 At the Congress at Chicago in 1893 Prof. Ayrton (Zhe Electrician, 1895, vol. xxxiv. pp. 336-7) first drew attention to the region of instability indicated by the dotted portions of the curves. At the same time he pointed out in Fig. 2, shown at Chicago, that whether the P.D. was descending as the current increased for, say, a 4 mm. arc, or was ascending for, say, a 0’5 mm. arc, it became quite constant for wide variations of current with a hissing arc. And, lastly, by a comparison of Fig. 2 with Fig. 3 he brought out the fact that the largest current that would flow silently with any given length of arc was increased by using thicker carbons; for the carbons in Fig. 3 have about twice the diameter of those in Fig. 2, and while the largest silent current for, say, the 2mm. arc in Fig. 2 is 15°5 amperes, that for the same length of are in Fig. 3 is about 49 amperes, or more than three times as great. Returning now to the subject of the dotted lines in Figs. 1, 2 and 3, it is plain that these divide the curves into two per- fectly separate parts, governed by different laws. For to the left of the dotted part the lines are all curved, and curved differently according as so/éd positive carbons are used as in Fig. 1, or coved as in Figs. 2 and 3, showing that with silent arcs the P.D. varies as the current varies, and that the law of variation is different with solid and cored carbons. To the right, on the other hand, the lines are all straight, and more or less parallel to the axis of current, whether the positive carbon is solid or cored, showing that with Azssdzg arcs the P.D. is the same for a given length of arc and a given pair of carbons, whatever current is flowing, and that this law is true whether the carbons be cored or solid. In fact, when the arc begins to hiss some complete and sudden break-down appears to occur, upsetting all the laws that have governed it while it was silent, and making cored and solid carbons behave alike. : Thus, our subject divides itself quite naturally into two dis- tinct portions, the one dealing with the arc when the break- down is imminent, but before it has actually occurred—dealing, that is to say, with the points at which the current is the largest that will flow silently—the A7ssézg points as I shall call them ; and the other dealing with the arc after the break-down has occurred, and when, therefore, the arc is really hissing. An examination of Fig. 1 shows that the hissing points lie well on the curve A BC; that curve may, therefore, be taken to embody the laws connecting the P.D. between the carbons, the current, and the length of the arc, at the Azsstng poents, for at least all those lengths of are given by the curves in Fig. 1. The most important of these laws concerns the current at the Azssing point, the largest sz/ent current. It is quite plain, from Fig. 1, that although this current in- creases as the length of the arc increases, yet it does not increase at the same rate as the length of the arc. For each millimetre added to the length of the arc involves a smaller and smaller addition to the largest silent current; so that finally a current must be reached which will not increase appreciably however much the arc is lengthened, always supposing that the law continues to hold for such long arcs. Hence, on this sup- position, for each pair of carbons the current that will sustain a normal silent arc has a maximum value, and any current greater than, this will make the arc hiss, however long it may be. Other laws concerning the arc when on the point of hissing and when actually hissing can be deduced directly from Figs. I, 2 and 3, but as these do not bear directly on the cause of hissing, the mathematical proofs of them may with advantage be omitted from the present article. Some of these laws may, however, be summed up as follows :— If V be the P.D. in volts between the carbons at the hissing point for an arc of 7 millimetres, and if V’ be the constant P.D. between the carbons for a hissing arc of the same length, then V =40°05 + 2°49 /, V'=29°25+2°75 /, and consequently V-V’=10'8 -—0'26/, which shows that ¢he longer the arc the less ts the P.D. between the carbons diminished when tt changes from silence to hissing, The numerical coefficients in the above equations naturally refer only to the carbons I used in my experiments, but the Zaws expressed by the equations must be true for a// direct current open arcs of lengths not differing very greatly from those I used, and burning between solid carbons. NO. 1551, VOL. 60] From Fig. 1 it might be supposed that, given the length of the arc, the increase of current that abruptly occurs on the arc starting hissing was as definite for that length of arc as the diminution in the P.D. And this, for a long time, I imagined to be the case. But while trying to find out what law connected the smallest hissing current with the length of the arc, I saw that the value of that current really depended on the circuit outstde the arc. I found, in fact, that when the largest silent current for any length of are changes to the smallest hissing current for the same length of arc, the value of that smallest hissing current depends on the E.M.F. of the dynamo ov/y. The smaller that E.M.F. is, the greater will be the smallest hissing current for any given length of arc, while if the E.M.F. of the dynamo could be made infinite, the smallest hissing cur- rent and the largest silent current would be equal; that is to say, when the arc began to hiss the P?.D. between the carbons would drop, but the current would remain quite unchanged. Thus it is possible, by choosing suitable E.M.F.s, to make the sudden smallest hissing current have any value greater than that of the largest silent current for the same length of arc. In 1889 Luggin found, by measuring the fall of potential between each carbon and the arc, that the principal part of the diminution of P.D. caused by hissing took place at the junction of the positive carbon and the arc. Some experiments of the same sort that I made about three years ago, using arcs varying between £ mm. and 6 mm., gave the same result. For the lengths of are dealt with, I found that hissing caused a mean fall of about 9°7 volts in the total P.D. between the carbons, and a mean fall of about 6°3 volts in the P. D. between the positive carbon and the arc. Hence of the whole diminution of the P.D, between the carbons caused by hissing, about two- thirds took place at the junction of the positive carbon and the arc. Further, my experiments showed that very little of the re- mainder of the diminution, if any, was due to a diminished fal] in the P.D. between the are and the negative carbon ; there- fore this remaining diminution must be attributed to a lowering of the resistance of the arc itself. We may sum up these results as follows :— Of the total diminution of the P.D. between the carbons caused by hissing, about two-thirds takes place at the junction of the posttive carbon and the arc, and the remaining third seems to be due to a lowering of the reststance of the arc ztself. We now pass from the consideration of the electrical measurements of the arc to the appearance of the crater, arc, and carbons. Every alteration of the current and of the distance between the carbons naturally produces a corresponding modification of all parts of the arc, but until the value of the current attains a certain magnitude, which depends only on the length of the are with a given pair of carbons, this change is one of degree merely, and not of character. A greater current simply pro- duces a larger crater, a larger arc, and longer points to the carbons. When the special current is reached, however, a change, which is no longer simply one of degree, takes place in that white-hot depression at the end of the positive carbon — from which most of the light of the arc is derived—the crater, © as it is called. Instead of presenting a uniformly. bright surface to the eye, this becomes partly covered with what appear to be alternately bright and dark bands, sometimes radial like the spokes of a wheel, sometimes in one or more sets of concentric circles, sometimes oscillating, sometimes rotating round different centres in opposite directions. The directions of rotation or oscillation and whole positions of the images change continu- ally, and the motion grows faster and faster as the current is increased. When the current is so much increased that the motion becomes too fast for the eye to detect, the are begins to hum, and then, as Mr. Trotter (Proc. Noy. Soc., vol. lvi. p. 262) first showed in 1894, it rotates at the rate of from 50 to 450 revolutions per second. As soon as hissing begins the whole appearance of the crater changes again; a sort of cloud seems to draw in round a part of it, moving from the outer edge inwards, and varying con- tinually in shape and position. Sometimes but one bright spot is left, sometimes several, but always the surface is divided into bright and dull parts, giving it a mottled appearance, as 1s slightly indicated in (6) Fig. 4. If, then, the current be diminished, so that the arc becomes silent again, the whole Jury 20, 1899] NATURE 285 surface of the crater grows dark for an instant, then brightens | in spots, and finally becomes bright again all over. The vaporous arc itself undergoes fewer modifications ; it preserves the ordinary characteristics of the silent arc while rotating wheels hold possession of the crater, but, when humming begins, a green light is seen to issue from the crater, and with hissing this becomes enlarged and intensified, till the whole centre of the purple core is occupied by a brilliant greenish-blue light, as is indicated in Fig. 5. ILENT. HISSING. Fic 4.—Cuarbons :—Positive, 9 mm. Cored ; Negative, 8 mm. Solid. Length of Arc. (a) 5 mm., (4) 8 mm. Current (a) 3°5 amperes, (4) 34 amperes. M. Blondel, whose accuracy of observation and originality in experiment have added so much to our knowledge of the arc, first mentioned a very curious fact about this vapour in 1893 (The Electrician, 1893, vol. xxxii. p. 170). He noticed that, while the arc was silent, the vapour was quite transparent, so that, when viewed at a proper angle, the crater could be seen through it perfectly; but that, as soon as hissing began, the vapour became so opique as to completely hide the crater. SILENT. SILENT. (6) (@) Fic. 6.—Carbons :—Positive, 11 mm. Solid; Negative, 9 mm. Solid. POINT OF HISSING. In any case, however, M. Blondel’s theory of a change from | vapour to solid particles in the arc when hissing begins seems to me to be hardly tenable, if only for the following reason, When- ever we put solid carbon into the arc, such, for instance, asa very thin carbon rod, it glows far more brilliantly than the surrounding vapour, and hence increases the luminosity of the arc. If, there- HISSING. Fic. 5 —Carbons :—Positive, 11 mm. Solid ; Negative, 9 mm. Solid. Length of Arc, 1.5 mm. Current, 28°5 amperes. | fore, hissing is accompanied by a substitution of solid particles. for the vapour of the arc, the luminosity of the arc should zucrease With hissing. But, M. Blondel mentions, in the same article, that the intrinsic brilliancy of the are d¢mznishes when hissiug begins, hence the theory of a disruptive discharge of solid particles does not appear to cover the facts. ON THE HISSING. (OQ) Length of Arc,2mm. Current, (a) 6 amperes, (4) 12 amperes, (c) 20 amperes, (@) 30 amperes. M. Blondel believes that, when hissing begins, the gentle evaporation of the carbon of the crater, which feeds the column of vapour in the silent arc, gives place to a disruptive discharge of solid particles torn from the crater. I have found the opacity of the hissing arc less complete and less invariable than M. Blondel, probably because my conditions were different from his. Indeed I have often been able to see the crater of a hissing arc through the vapour as clearly as if the arc were silent. NO. 1551, VOL. 60] The shafe of the arc also alters when hissing begins. When the arc is silent its shape is rounded, and it has an appear- ance of great stability; but as soon as hissing occurs, it seems | suddenly to dart out from between the carbons and to become flattened out, as if under the influence of a centrifugal force act- ing at right angles to the common axis of the two carbons. In Fig. 5 and in (d@) Fig. 6, this flattened appearance is well marked ; and indeed these figures show that every part of the vaporous arc itself isinvolved in this flatteaing—the purple core, 286 INACRO LEE: the shadow round it, and the green aureole—asif they were all revolving with great rapidity round a common axis. And what more likely than that this should be the case, since, as has already been mentioned, the are is revolving at the rate of 450 revolutions per second at ¢he moment that it starts hissing ? As regards the carbons themselves, the only important modification of the zega¢zve carbon that appears to be due to hissing is the formation of the well-known ‘‘ mushroom” at the end of that carbon with a short hissing arc. This mushroom, of which a good example is seen in Fig. 5, is well named, not only because ofits shape, but also because of the rapidity of its growth, which is so great that, while it is forming, the carbons often have to be separated, instead of being brought together, to keep the length of the are constant. (Zo be continued.) HVBRIDISA TION. UR first duty, and a very pleasant one it is, is to welcome our foreign guests, our friends from across the sea, as I prefer to call them, to thank them for their presence here to-day, and to express a hope that their sojourn among us may be both agree- able and profitable. At the same time we regret that some, such as Dr. Focke, the historian of hybridisation, has not been able to preside over this meeting, as we had hoped he might have done. Nor can we at such a meeting do other than express our abiding regret at the loss, though at an advanced age, of the great hybridiser Charles Naudin. Our next duty is to thank the Council of the Royal Horti- cultural Society for this opportunity of meeting once more in these time-honoured gardens to discuss what I venture to think is one of the, if not the most, important subject in modern pro- gressive experimental horticulture. I use the words progres- sive and experimental because I believe that the future of horticulture depends very greatly on well-directed experiment. So far as the details of practical cultivation are concerned, we are not so much in advance of our forefathers. We have infinitely greater advantages, and we have made use of them, but if they had had them they would have done the same. We are able to bring to bear on our art not only the ‘‘ resources of civilisation ” to a degree impossible to our predecessors, but we can avail ourselves also of the teachings of science, and endeavour to apply them for the benefit of practical gardening. We are mere infants in this matter at present, and we can only dimly perceive the enormous strides that gardening will make when more fully guided and directed by scientific investigations. One object of this conference is to show that cultural excellence by itself will not secure progress, and to forward this progress by discussing the subject of cross-breeding and hybridisation in all their degrees, alike in their practical and in their scientific aspects. To appreciate the importance of cross-breeding and hybrid- isation we have only to look round our gardens and our exhibition-tents, or to scan the catalogues of our nurserymen. Selection has done and is doing much for the improvement of our plants, but it is cross-breeding which has furnished us with the materials for selection. A few years ago by the expression ‘‘ new plants ” we meant plants newly introduced from other countries, but, with the possible exception of orchids, the number of new plants of this description is now relatively few. The ‘‘new plants” of the present day, like the roses, the chrysanthemums, the fuchsias, and so many others, are the products of the gardeners’ skill. From peaches to potatoes, from peas to plums, from strawberries to savoys, the work of the cross-breeder is seen improving the quality and the quantity of our products, adapting them to different climates and con- ditions, hastening their production in spring, prolonging their duration in autumn.* Surely in these matters we have out- distanced our ancestors, But let us not forget that they showed us the way. ” I do not 1 Substance of the address by Dr. Maxwell T. Masters, F.R.S., delivered on opening the proceedings of the International Conference on ‘* Hybridis- ation,”’ Tuesday, July rz. * See some interesting observations of MacFarlane on the period of flowering in hybrids as intermediate between that of the parents, Gardeners’ Chronicle, June 20, 1891 ; and on the structure of hybrids, May 3, 1890. NO. 1551, VOL, 60] [JuLY 20, 1899 propose to dilate on the share which Camerarius, Millington, Grew, Morland, and others, at the close of the seventeenth cen- tury had in definitely establishing the fact of sexuality in plants, but I do wish to emphasise the fact that it was by experiment, not by speculation, nor even by observation, that the fact was proved, and I do wish to show that our English gardeners and experimenters were even at that time quite aware of the importance of their discovery, and forestalled our Herbert and Darwin in the inferences they drew from it. In proof of which allow me to quote from a work of Richard Bradley, called ‘““New Improvements of Planting and Gardening, both Philosophical and Practical,” published in 1717, cap. ii. After alluding to the discovery of the method of the fertilisation of plants, he says (p. 22) :— “By this knowledge we may alter the property and taste of any /vuzt by impregnating the one with the /arzza of another of the same class; as, for example, a Cod/én with a Pearmain, which will occasion the Cod/zx so impregnated to last a longer time than usual, and be of a sharper taste ; or if the Weter Fruits should be fecundated with the Dust of the Swmmer kinds, they will decay before their usual Time ; and it is from this accidental coupling of the Fara of one with the other, that in an Orchard where there is Variety of 4ff/es, even the Fruit are gathered from the same 77ee differ in their Flavour and Times of ripening; and, moreover, the Seeds of those Apples so generated, being changed by that Means from their Natural Qualities, will produce different kinds of Fruit if they are sown. ‘Tis from this accidental coupling that proceeds the number- less varieties of Fruits and Flowers which are raised every day from Seed. . . - “Moreover, a curious Person may by this knowledge produce such rare kinds of Plants as have not yet been heard of, by making choice of two //ants for his Purpose, as are near alike in their Parts, but chiefly in their /Vowers or Seed vessels ; for example, the Carnation and Sweet William are in some respects alike, the Marca of the one will impregnate the other, and the Seed so enlivened will produce a Plan¢ differing from either, as may now be seen inthe garden of Mr. Thomas Fairchild, of Hoxton, a plant neither Sweet Welliam nor Carnation, but resembling both equally, which was raised from the seed of a Carnation that had been impregnated by the Farzza of the Sweet William.” Here we have the first record of an artificially-produced hybrid, and you will remark that this was more than forty years before Kolreuter began his elaborate series of experiments. Fairchild was the friend and associate of Philip Miller, and of a small knot of advanced thinkers and workers who banded themselves together into a ‘‘ Society of Gardeners.” “He is mentioned,” says Johnson in his ‘‘ History of English Gardening,” ‘‘ throughout Bradley’s works as a man of general information, and fond of scientific research, and in them are given many of his experiments to demonstrate the sexuality of plants, and their possession of a circulatory system. He was a commercial gardener at Hoxton, carrying on one of the largest trades as a nurseryman and florist that were then estab- lished. He was one of the largest English cultivators of a vine- yard, of which he had one at Hoxton as late as 1722. He died in 1729, leaving funds for insuring the delivery of a sermon annually in the church of St. Leonard’s, Shoreditch, on Whit Tuesday, ‘On the wonderful works of God in the Creation ; or On the certainty of the resurrection of the dead, proved by the certain changes of the animal and vegetable parts of the creation.’ ” Fairchild was thus not only the raiser of the first garden hybrid, but the originator of the flower services now popular in our churches. We do not hear much of intentionally-raised hybrids from this time till that of Linnzeus, in 1759 (‘‘ Ameen. Acad.,” ed, Gili- bert, vol. i. p. 212). The great Swedish naturalist, having observed in his garden a Tragopogon, apparently a hybrid between 7. pratensis and 7. parvifolius, set to work to ascertain whether this;conjecture was correct. Ie placed pollen of 7: parvifolius on to the stigmas of 7. fratenszs, obtained seed, and from this seed the hybrid was produced. About the same time (that is, in 1760) Kolreuter began his elaborate experiments, but these were made with no practical aim, and thus for a time suffered unmerited oblivion. Some years after, the President of this Society, Thomas JuLy 20, 1899] Andrew Knight, and especially Dean Herbert, took up the work, with what splendid results you all know. It is curious, however, to note that objections and prejudices arose from two sources. Many worthy people objected to the production of hybrids, on the ground that it was an impious interference with the laws of nature. To such an extent was this prejudice carried, that a former firm of nurserymen at Tooting, celebrated in their day for the culture, amongst other things, of heaths, in order to avoid wounding sensitive suscept- ibilities, exhibited as new species introduced from the Cape of Good Hope forms which had really been originated by cross- breeding in their own nurseries. The best answer to this prejudice was supplied by Dean Herbert, whose orthodoxy was beyond suspicion. He, like Linnzus before him, had observed the existence of natural hybrids, and he set to work experimentally to prove the justness of his opinion. He succeeded in raising, as Engleheart has done since, many hybrid narcissi, such as he had seen wild in the Pyrenees, by means of artificial cross-breeding. If such forms exist in nature, there can be no impropriety in producing them by the art of the gardener. In our own time, Reichenbach, judging from appearances, described as natural hybrids numerous orchids. Veitch and others have confirmed the conjecture by producing by arti- ficial fertilisation the very same forms which the botanist described. It remains only to speak of another respectable but mistaken prejudice that has existed against the extension of hybridisation. I am sorry to say this has been on the part of the botanists. It is not indeed altogether surprising that the botanists should have objected to the inconvenience and confusion introduced into their systems of classification by the introduction of hybrids and mongrels, and that they should object to hybrid species, and much more to hybrid genera ; but it would be very unscientific to prefer the interests of our systems to the discovery of the truth. I may mention two cases where scepticism still exists as to the real nature of certain plants: Clematis jackmanz of our gardens, raised, as is alleged, by Mr. Jackman, of Woking (Gardeners Chronicle, 1864, p. 825), was considered by M. Decaisne and M. Lavallée! to be a real Japanese species, and not a hybrid. This may be so, but there is no absolute im- possibility in the conjecture that the Japanese plant and the cultivated plant originated in the same way. Again, Mr. Cul- verwell’s supposed hybrid between the strawberry and the rasp- berry has been pronounced to be no hybrid, but to be Rzzdzs Zeesti. But what, we may ask, is Rubus leestz? It appears to be a sterile form more closely allied to the raspberry than to the strawberry. Is it not at least possible that Mr. Culverwell has produced it artificially ? The days when ‘‘species” were deemed sacrosanct, and ‘“systems” were considered ‘‘natural” have passed, and Darwin, just as Herbert did in another way, has taught us to welcome hybridisation as one means of ascertaining the true relationships of plants and the limitations of species and genera. Darwin’s researches and experiments on cross-fertilisation came as a revelation to many practical experimenters, and we recall with something akin to humiliation the fact that we had been for years exercising ourselves about the relative merits of “*pin eyes” and ‘‘thrum eyes” in primroses, without ever perceiving the vast significance of these apparently trifling details of structure. It would occupy too much time were I to dilate upon the labours of Gaertner, of Godron, of Naudin, of Naegeli, of Millardet, of Lord Penzance, of Engleheart, and many others. Nor need I do more than make a passing reference to the wonderful morphological results obtained by the successive crossings and inter-crossings of the tuberous begonias, changes so remarkable that a French botanist was even constrained to found a new genus, Lemoinea, so widely have they deviated from the typical begonias. For scientific reasons, then, no less than for practical purposes, the study of cross-breeding is most important, and we welcome the opportunity that this conference affords of extending our knowledge of the life-history of plants, in full confidence that it will not only increase our stock of knowledge, but also enable us still further to apply it to the benefit of mankind. 1 Lavallée, ‘‘ Les Clematites 4 Grandes Fleurs,” p. 6 and p. 9, tab. iv.: Clematis hakonensis. NO. 1551, VOL. 60] NATURE 287 UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Dr. A. C, Houston has been appointed Lecturer in Bacteri- ology at Bedford College, London, for Women. Dr. W. WAcE CARLIER, at present Lecturer on Experimental Physiology and Histology in the University of Edinburgh, has been appointed Professor of Physiology in Mason University College, Birmingham, THE Royal Commissioners for the Exhibition of 1851 have approved the nomination by the University College of North Wales of Mr. Robert Duncombe Abell to a Science Research Scholarship of the value of 1507. a year. Mr. Abell is about to enter the University of Leipzig, where he proposes to engage in a special research under the direction of Prof. Wislicenus. THE following appointments abroad may be noticed :—Dr. James Ewing to be professor of pathology in the Cornell University Medical College; Dr. Charles W. Wardner to be professor of physics in Williams College; Dr. H. G. Byers ta be professor of chemistry in the State University of Washing- ton; Dr. Alfred H. Seal to be professor of chemistry in Girard College, Philadelphia. THE new buildings of the London Hospital Medical College were opened on Tuesday last. They occupy the site of the old chemical theatre and laboratory, and comprise the following rooms and departments. On the basement is the department of public health, containing a large museum, professors’ room, class rooms, &c. ; on the ground floor, the biological laboratory, class rooms, and the materia medica museum ; on the first floor, the chemical theatre and laboratories, and the balance room ; on the second floor, the physics laboratory, the chemical labor- atory for the diploma in public health classes, the operative surgery room, and a large anatomy class room leading from the dissecting room. On the third floor is the bacteriological department, with general laboratory, research laboratories, class rooms for public health work, sterilising room, &c. Other portions of the building have thus been left for additional development, and advantage has been taken of this to provide special class rooms for students studying for the preliminary scientific, the intermediate M.B., London, and other examin- ations. Additions have also been made to the present physio- logical department, giving rooms for original research and for special class work for the higher examinations. For all these departments special teachers have already been appointed, who are devoting their entire time to the particular subjects that they have undertaken. The new buildings, with their fittings, will cost altogether not less than 10,000/. SCIENTIFIC SERIAL. Bollettino della Socteta Sismologica Ltaliana, vol. v. No. 1, 1899-1900. —The rules of the Society and list of Fellows (forty- three national and ten foreign) are given.—Determination of the epicentre and time at the origin of earthquakes of unknown origin propagated along the earth’s surface by means of four or five time-observations, by G. Costanzi. Equations for the above purposes are obtained on the supposition that the surface-velocity is constant.—Vesuvian notices (July-December 1898), by G. Mercalli. A monthly chronicle, with notes on the paroxysm of September, the central crater, and the excentric eruptive appa- ratus; illustrated by reproductions of two photographs.—Notices of the earthquakes observed in Italy (January 1-February 3, 1898), by G. Agamennone, the most important being the Ferrara earthquake of January 16, a distant earthquake on January 25, and the Asia Minor earthquake of January 29. SOCIETIES AND ACADEMIES. LONDON. Royal Society, June 15.—‘‘ Qn the Application of Fourier’s Double Integrals to Optical Problems.” By Charles Godfrey, B.A. The disturbance received at any point from a luminous body is a vector, varying with the time. It may be defined by its resolved parts along three rectangular axes; let /(2) be one of these resolutes. In general /(¢) will not be a periodic function, 288 even when the light is approximately monochromatic. By Fourier’s theorem of double integrals he) = I (Ccos wt + S sin zt) tv, where +0 +n rif : G=2 [fe coswudv, S = — | A) sin wwe. | TT | mes x This is true provided /(/) is subject to certain conditions, which are proved to be present in any physical problem. The object of the paper is to inquire whether the above theorem justifies us in regarding any plane-polarised plane light motion as equiva- lent to acombination of simple harmonic vibrations, with periods varying from oto”. The element of the integral suggests a vibration of amplitude da /C? + S2, phase tan 2S and period on : ; ¢ : —, Itis proved that in certain very general cases such an in- ue lerpretation is possible, notably in the case of ‘* constant” light, such as presents a steady appearance. This calculus enables us to discuss the width of the lines in the spectrum of an incandescent gas, taking into account not only the velocities of the molecules, but also the effect of collisions, and of radiative damping in the molecular vibrations. The con- nection between Rontgen rays and ordinary light is examined, J. J. Thomson’s theory of the former being assumed. It is shown hat perhaps ;j'5a of the energy of the rays will be in the visible spectrum. The theory of dispersion is considered with reference tonatural light as opposed to a simple harmonic train of waves. Paris. Academy of Sciences, July 10.—M. van Tieghem in the chair.—The Perpetual Secretary announced to the Academy the loss it had sustained by the death of Sir William Flower, Corre- spondent in the Section of Anatomy and Zoology.—Remarks by M. Ed. Perrier on his Zyazté de Zoologze.—New researches on argon and its combinations, by M. Berthelot. Having a larger quantity of argon placed at his disposal, the author has repeated his earlier observations on the reactions between argon and cer- tain organic compounds. Entirely negative results were obtained when mixtures of argon with ethylene, glycollic ether, aldehyde, acetone, amylene, petroleum ether, propionitrile, allyl sulpho- cyanide, or amylamine were submitted to the prolonged action of the silent discharge, the original volume of argon being re- covered unchanged. With benzene, toluene, cymol, turpentine, anisol, phenol, benzaldehyde, aniline, phenyl sulphocyanide, and benzonitrile, on the other hand, an absorption of argon took place inamounts varying from one to six per cent. At the same time a greenish fluorescence appeared, giving a characteristic spectrum.—On the geographical and cartographical work carried out in Madagascar by order of General Gallieni between 1897 and 1899, by M. Alfred Grandidier. The values previously assumed for the latitude and longitude of Tamatave, Andé- vorante, Fort Dauphin, and other towns in Madagascar are here revised, and the differences tabulated. —On the dialkylbenzoyl- benzoic acids and their tetra-chlor-derivatives, by MM. A. Haller and H. Umbgrove. Details are given of the prepar- ation and properties of tetrachlordimethylamidobenzoyl- benzoic acid, acetyldimethylamidobenzoyltetrachlorbenzoic anhydride and the corresponding ethyl and _ methyl ethers, dimethylamidobenzoyltetrachlorbenzoic acid and the anhydride of acetyldiethylamidobenzoyltetrachlorbenzoic acid, together with its ethyl and methyl ethers.—On the de- velopment of analytical functions of several variables, by M. Paul Painlevé.—Contribution to the theory of musical instru- ments, by M. Firmin Larroque.— Remarks on the use of cryo- hydrates, by M. A. Ponsot.—Action of nitric oxide upon chrom- ous salts, by M. Chesnau. Chromous salts in solution dissolve nitric oxide like ferrous salts, giving only one compound. On heating, or placing in a vacuum, this compound gives off no gas, thus differing from the corresponding ferrous compound. — On metallic sulphantimonites, by M. Pouget. Solutions of potassium sulphantimonites by double decomposition with salts of metals may give salts of the types SbS,M3, or SbS;M.K, but in no case of the type SbS,MK,.—Action of phenylhydrazine upon alcoholic bromides, chlorides, and iodides, by M. J. Allain Le Canu. The iodides behave differently to the cor- NO. 1551, VOL. 60] NATURE [Jury 20, 1899 responding bromides and chlorides in respect to their reaction with phenylhydrazine —On the aminocampholenes, by MM. E. E. Blaise and G. Blanc.—Contribution to the study of an oxyptomaine, by M. Cichsner de Coninck. The oxyptomaine C,H,,NO was prepared by the action of hydrogen peroxide upon the pyridic ptomaine, CgH,,N. In the present paper details are given of its bromohydrate, chloroaurate, and chloromercurate. —New method for the acidimetric estimation of alkaloids, by M. Elie Faliéres. The titration is conducted with an am- moniacal copper solution instead of litmus or one of the ordinary indicators. The experimental results were very satis- factory.—On_ benzoyl]-furfurane, by M. R. Marquis. Benzoyl- furfurane is readily obtained by the interaction of pyromucyl chloride and benzene in presence of aluminium chloride. —The egols, new general antiseptics, by M. E. Gautrelet. Parasulphones derived from phenols are nitrated, and the ortho-nitro-phenol- parasulphonate of mercury and potassium prepared from this. The compounds thus obtained are termed egols, phenegol from phenol, cresegol from cresol, and so on, and possess certain advantages as antiseptic agents.—The 7d/e of heat in muscle action, by M. Raphael Dubois. —New observations on echidnase, by M. C. Phisalix. This ferment is present in snake poison, and is found to exert a di:static action not only upon anima} tissues, but even upon the active principle of snake poison, echidnotoxin. —Analogies between cultures of the vegetable fungus Mectrza and the parasitic fungus in human cancer, by M. Bra.—On the absence of regeneration of the posterior mem- bers of the leaping Orthoptera and its probable causes, by M. Edmond Bordage.—On the affinities of AZzcrosporum, by MM. L. Matruchot and Ch. Dassonville.—On the cicatrisation of the fascicular system, and of the secretory apparatus on the falling of the leaf, by M. A. Tison.—Barometric deviations on the meridian of the sun at successive days of the synodic revolution, by M. A. Poincaré.—On the use of self-recording meteorological apparatus in captive balloon ascents, by M. Léon Teisserenc de Bort. CONTENTS. Prestwich and Practical Geology . Oe oe Meteorology, Old and New. By W. E. P. Bieta 62462 Machines for the Liquefaction of Gases . ae A Manual of Anthropology. ........... 269 Our Book Shelf :— Ladd: ‘‘A Theory of Reality."—H. W. B. .. . 270 “Great and Small Game of Africa.”—R. L. . Adie : ‘‘ An Introduction to the Carbon Compounds.” —A.' Hi... Aes ks ey Letter to the Editor:— On the Deduction of Increase-Rates from Physical and other Tables.—Prof. J. D. Everett, F.R.S. 271 The Penycuik — (Lilustrated.) By F. A. D. 56.6 6 CLO oS AS Pioneer Cimber! Gaenreted!) By, Profi@ivGa Bonney, F.R.S., °c eee 274 Bower-Birds. ([iustrated.} By R. L. ie : 275 The Cosmic Origin of Moldavite. (///ustrated.) . 276 Notes ofa 277 Our AGironomicall Cotten: -- Tempel’s Comet 1899 ¢ (1873 II.) . 28 Holmes’ Comet 1899 a (1892 III.) 281 Dynamical Theory of Nebulz 281 The Natal Observatory : F 281 Temperature Changes in Yerkes (object: was 3 281 The Reason for the Hissing of the Electric Arc. (Lilustrated.) By Mrs.W. E. Ayrton . pee, 282 Hybridisation. By Dr. Maxwell T. Masters, eR SS. 3 aie . ee 286 University and watcaneeal fretellizence 287 Scientific Serial | 5 5m > ORS os oo kg Societies and Academies . 287 ARO REE 289 THURSDAY, JULY 27, 1899. INORGANIC CHEMISTRY. Lehrbuch der Anorganischen Chemie. Von Prof. Dr. H. Erdmann. Pp. 728. (Brunswick: Vieweg und Sohn, 1898.) HIS book is based upon the well-known work of Gorup-Besanez, the last edition of which was published in 1878, but it is practically a new book. It is printed in the style of Roscoe and Schorlemmer’s treatise, handsomely illustrated, and well bound. In the 728 pages a vast amount of information is given about the facts of inorganic chemistry, and this information is in most respects well abreast of the time. The treatment and presentation of the subject are quite orthodox, except in so far as the description of experiments and of technical applications is separated from the main text, and printed in smaller type after the more general and descriptive account of asubstance or group of substances has been written. It is, perhaps, asking a good deal that a new book on inorganic chemistry should differ much except in size or price from: contemporaneous works on the same subject. A perusal of the present work proceeds without any sense of freshness until the sections on helium and argon, where for the first time the personal authority of the writer is felt and approving interest excited. After this the even tenor is resumed until the second part of the work dealing with the metallic elements is reached. Here again interest is aroused, and the author may be congratulated on having produced a very readable account of what, scientifically speaking, is usually the dullest part of a book on inorganic chemistry. The accounts of technical applications which are intercalated in the text are very well written, interesting, and trust- worthy. The chief question raised by this book is how far theory is to be introduced into a book on inorganic chemistry. Is a book on inorganic chemistry to be a compendium of facts, whilst the theory is to be sought in books on general or physical chemistry? As a matter of fact, books on inorganic chetnistry written up to about 1870 included a discussion of all that was known of theoretical and physical chemistry. Till then the only important quantitative laws that were clearly established referred to composition, and accordingly the theoretical part of such books dealt mainly with the laws of chemical combination and the atomic and molecular theories. But things have advanced since then; we now know a great deal about chemical dynamics, and it seems anomalous that in such a book as the one under notice there should be no general ex- position of the laws governing chemical reactions and chemical equilibrium. These laws, like the laws of com- position, are fundamental, and the light they throw on every-day inorganic chemistry is indispensable fora right apprehension of the facts. There seems no good reason for neglecting them in a book of 700 pages dealing with inorganic chemistry. The theoretical part of the book is also in other respects the least satisfactory feature. It displays much of the NO. 1552, VOL. 60] anxious striving, to which some minds seem peculiarly liable, to be fundamental and logical on points where such exercitation is quite unnecessary and unfruitful. An advanced student surely does not need to be carefully initiated into the difference between Roman and Arabic numerals, or the meaning of 10%, or the impossibility of putting a quart of liquid into a pint pot; yet these and like matters are gravely and lengthily expounded. The effect is to submerge the salient points of doctrine in a sea of tedious disquisition. One cannot but wish that the space so used had been saved for the discussion of such important theoretical matters as the constitution of ozone, the hydration of salts, the absorption of hydrogen by metals, the atomic weight of tellurium— topics to which justice is not done in the book. There are some omissions and a few mistakes in the book. The account of flame includes the apparently ineradicable dogma that the hydrogen of a hydrocarbon burns preferentially to the carbon, and that solid particles of carbon are burnt up inthe mantle. ‘The rate of the explosive wave is confused with the velocity of inflam- mation, and the acetylene flame, which readily meits a platinum wire, is stated to be peculiarly cool. The blemishes in the book on matters of fact are, however, not many; the information is indeed, on the whole, admirable, and we have no doubt that Prof. Erdmann’s work will on this account meet the requirements of a large class of students. ACrSs MARINE BOILERS. Marine Boilers. ‘Wy L. E. Bertin ; translated and edited by L. S. Robertson, with a preface by Sir William White, F.R.S. Pp. xxviii + 437. (London: John Murray, 1898.) HIS is a translation, with some important alterations and additions, of M. Bertin’s well-known work on marine boilers. M. Bertin, now Director of Naval Con- struction for the French Navy, was previously Principal ofthe Ecole @application du Génie Maritime, and his text-book was the outcome of the course of lectures on boiler construction which he delivered to the students of that institution. The work has been translated by Mr. L. S. Robertson, an authority on the so-called water-tube boiler, and has the advantage of a graceful tribute to M. Bertin’s skill as an engineer and naval architect in the form of a preface by Sir William White, Chief Constructor to the British Navy. The book is copiously illustrated, but unfortunately the plates are sometimes by no means clear, and where dimensions are given it is often impossible to read them ; as the illustrations are reproductions of those in the original French work, the dimensions are in metric units, while all the dimensions in the text have been converted into English units. Fewer illustrations, more clearly reproduced, would have been an improvement ; though these remarks apply in the main to the general drawings only, the detail drawings being much clearer. The author has divided the book into four parts, and has covered fairly completely the whole field. Part i. is devoted to the important subjects of combustion, trans- oO 290 mission of heat, corrosion, &c., and to the various methods for producing draught, with a discussion of the ad- vantages and disadvantages of the various systems. On p. 45 there is a slip, probably arising in conver- sion of units: it is stated that 5°89 lbs. of oxygen are needed to burn a pound of carbon; the figure should be 2°67 lbs. In discussing the possibility of the utilisation of the heat passing away up the funnel for warming either the feed water or the air before it passes into the furnace, there is a somewhat cur ious remark about the heat wasted in condensing the exhaust steam from an engine by cold water in the condenser, the author stating that so far “‘no remedy for this evil” had been proposed. Surely it has been forgotten that since the engine can only convert into work a small portion afterall of the heat it receives, there must be rejection of heat in the condenser or else- where. In discussing the effects of corrosion in tubes, it is laid down as an axiom that only solid drawn tubes should be used, on account of the liability of the welded tube to suffer injury by corrosion along the line of weld, a remark which is sadly significant after the late disaster toa boiler in H.M.S. Zervrzéle, and the finding of the Court of Inquiry. The next two parts deal in detail with the older forms of marine boilers, the Scotch boiler mainly, and the newer tubulous or water-tube boiler. Very full descriptions are given in the second section of the more important details in a cylindrical boiler, especially in regard to the tubes and to the stays, and the section concludes with a valuable table of weights, space occupied, &c. The third section, on water-tube boilers, is the most complete and the most interesting, as was to be ex- pected, the tubulous boiler now reigning almost supreme in the French navy, and its use in the French mercantile marine being fairly large. Three classes of such boilers are described in three separate chapters—the limited circulation class, type Belleville ; the free circulation, types Niclausse, Babcock-Wilcox, &c. ; and lastly the accelerated circulation, types Normand, Thorny croft, Yarrow, &c. In each chapter practically every boiler of the class under description which has been actually tried in prac- tice is illustrated and briefly explained, while very full detailed descriptions are given of one or two of the important forms, such as Belleville, Niclausse, Thorny- croft, &c., with much valuable information as to their performances under steam. The last chapter in Part iil. is devoted to an able summary of the advantages and disadvantages of the tubulous type of boiler, mainly, of course, from the point of view of the marine engineer; interesting contrast- ing figures of comparative weights, costs, &c., per square foot of grate render this chapter one of the most useful in the book. It is surprising how cheap these apparently complex water-tube boilers are, averaging 32/. per square foot of grate surface. The four chapters in Part iv. are devoted to descrip- tions of boiler mountings and fittings, in particular to the automatic feed arrangements, so essential to many water- tube boilers; in these chapters the illustrations are very good. The book undoubtedly is the most complete work on the subject issued in English up to the present, and is NO. 1552, VOL. 60] NATURE [JuLy 27, 1899 well up to date; it should prove a valuable work of reference, not only to the marine engineer, but to the intelligent layman who takes an interest in the efficiency of our navy. The water-tube boiler, much as Mr. Allen may dislike it, has come to stay; in our navy it will gradually displace the old Scotch boiler, and we should be surprised if it does not eventually make headway in the mercantile marine. : Any one reading the book and anxious to ascertain the trend of opinion amongst English marine engineers on this important question should consult the papers read a month or two ago before the Institution of Civil Engineers by Mr. Milton and Sir John Durston. lly 514 OUR BOOK SHELF. The Elements of Euclid. With Notes, &c., by I. Tod- hunter, D.Sc, F.R.S. New edition, revised and enlarged, by S.L. Loney, M.A. Pp. vilit+332, cxxxij. (London : Macmillan and Co., 1899.) Essentials of Plane and Solid Geometry. By W. Wells, S.B. Pp. vilit392. (London: Isbister and Co. Boston, D.C. : Heath and Co., 1899.) WITHOUT altering the general character of the well- known text-book with which he has had to deal, Mr. Loney has succeeded very well in bringing it up to date. The appendix has been enlarged by the insertion of sections on poles and polars, harmonic ranges, inversion, coaxal circles, &c.; the number of exercises has been doubled, and, what is more important, the really valuable exercises have been starred and hints given for the solu- tion of many of them. To teachers of the conservative school this new edition ought to prove very acceptable. Mr. Wells’ book is of quite another stamp. The author belongs to the progressive party, and makes no scruple of using hypothetical constructions or any ab- breviations he finds convenient. In treating of parallels he uses Playfair’s axiom, and the discussion of ratio and proportion is distinctly arithmetical. The exercises are numerous and often accompanied by figures ; hints for solution are also given in many cases. Mr. Wells writes in a fresh and independent manner, and his book seems very likely to interest a student and develop any geo- metrical power he may have in the right way. In another edition the author will, we trust, suppress the appendix (p. 386), which is almost entirely vitiated by an error of reasoning. Mr. Wells proposes, for instance, to prove that the circumference of a circle is less than the perimeter of any circumscribed polygon, and pro- ceeds thus: “Of the perimeters of the circle and of its circumscribed polygons, there must be one perimeter such that all the others are of equal or greater length.” He then proves that, given any circumscribed polygon, we can construct another ene with less perimeter ; and then infers the truth of the proposition. As a matter of fact, the statement quoted above is not justifiable; the perimeters of the polygons form a manifold, and this does not necessarily contain a least element ; indeed, Mr. Wells shows that it does not. There may be a definite lower limit to the perimeter of a circumscribed polygon : even then, Mr. Wells brings forward no argument to show that this lower limit exists ; still less that it is equal to the circumference of the circle. Strictly speaking, he brings the circumference of the circle into no relation of equality or inequality with any of the polygons: it just stands by itself at the end asat the beginning. It is as if one said: “We have a set of quantities x, 1°3, 1°33, 1°333, &c. ; one of these must be at least equal to any of the rest. But this cannot be any of the decimals, because if we choose, JuLy 27, 1899] "2222 ‘Say, 1°3333, we Can write down 1°33333, which is greater. Therefore tt must be x!” It is only fair to add that this unlucky paralogism seems to be a solitary blemish in an otherwise excellent book. G. B. M. A Manual of Surgical Treatment. By W. Watson Cheyne, F.R.S., and F. F. Burghard, M.S., Surgeons to King’s College Hospital, London. In six Parts. Part I. Pp. xiv + 285, with 66 illustrations in the text. (London and Bombay: Longmans, Green, and Co., 1899.) SUCH a work as this has long been wanted by senior students, house-surgeons and general practitioners, who are often left in charge of capital operations performed by surgeons of repute without any precise directions as to the treatment to be adopted in cases of emergency. But the work undertakes much more than this, for it is evident that the authors will review the whole field of surgery in the light of our present pathological know- ledge, showing the modern methods of treatment and explaining why they have replaced the older plans. The present part deals with the more general subjects of inflammation, gangrene, wounds, venereal disease, tuber- culosis and tumours. It treats, therefore, of those parts of surgery which, perhaps more than all others, have been affected by antiseptic treatment. Mr. Watson Cheyne is so well known as one of the most distinguished pupils of Lord Lister that no better exponent of his methods could be found, and we are here presented with a clear account of the rationale of modern treatment. Thus, amongst many other more important things, we learn why poulticing is bad in the treatment of abscess, why a chronic abscess should be scraped, but an acute abscess should only have the matter let out and the loculi broken down. The facts and reasoning are ex- cellent, but the pleasure of reading is too often marred by the form in which they are presented, as many of the sentences seem to be constructed upon a German model. The figures which illustrate the letterpress vary greatly in quality ; some are excellent, others are sketchy, whilst others again are such mere outlines as to be almost unintelligible. Dr, Silk contributes an excellent article on the subject of anzesthetics, and there is a good index to this first part of the work. Inipressions of America. By T. C. Porter, M.A. (Oxon.), Fellow of the Chemical Society, of the Royal Astro- nomical Society, and of the Physical Society of London. Illustrated with diagrams and stereoscopic views. Pp. xvii + 242. (London: C. Arthur Pearson, Ltd., 1899.) THE impressions were obtained during a pleasure trip to Niagara, the Yellowstone Park, San Francisco, the Yosemite, Utah and Colorado Springs. The author re- frains from citing any of the scientific works dealing with the remarkable features of those interesting regions, but gives a graphic account of what he himself saw, and out- lines a number of interesting hypotheses to account for some of the phenomena. Some of these are interesting because they show how a man of scientific habits of thought may from a hasty glance often reach con- clusions very similar to those which the specialists who have studied the subject for years have demonstrated to be correct. We cannot accept Mr. Porter’s ingenious hypothesis that the spiral ridges of the trunks of many trees in the Yellowstone Park are due to unequal heating by the sun and the uniform rotation of the earth, because he does not buttress it with the necessary ex- planation why trees in other places in the same latitude where the sun also shines unequally and the earth rotates uniformly do not also incline to a screwy form. But the little appendix on the Gulf Stream is a neat demonstra- tion from the study of a single bottle-chart of the seasonal NO. 1552, VOL. 60] NATURE 291 variation of the Gulf Stream and its attendant drift. Of course the deduction is not new ; the fine charts of North Atlantic currents grouped for two-monthly intervals by the Meteorological Office bring it out perfectly, and the labours of American, British, and Scandinavian ocean- ographers, and of the Prince of Monaco, have done much to find the reasons for the observed variations. We might venture, however, to remind Mr. Porter that the course of the Gulf Stream shown on a single small scale map is as conventional and empirical a representation of oceanic circulation as the isotherms on a map of mean annual temperature are of the climates of the world. The generalisation in no way implies that the seasonal changes are unknown. A new theory of geysers to fit the phenomena of the Yellowstone Park is also printed in the appendix in the form of a paper read to the Physical Society. It points out defects in Tyndall’s well-known theory, and intro- duces a syphon-bend in the underground channel and the spheroidal state induced by the intense heat of the rocks as more probable explanations. The great merit-and the unique character of the book depend, however, not on the author’s impressions or his theories, but on the incomparable series of photographs which he took. These are reproduced in the form of stereoscopic views, and aneat little lenticular stereoscope is supplied with the volume. The views shown in these illustrations are admirably selected and splendidly photo- graphed. They are reproduced by the half-tone process as separate plates, and very well printed. As a diary of the observations of a man of science at leisure there is much of interest in the whole book, which has also the advantage of being brief. H. R. M. Tables for Quantitative Metallurgical Analysis for Laboratory Use. By J. James Morgan, F.C.S., Member Soc. Chem. Industry, Member Cleveland Inst. Engineers. Tables xvi. (London: Charles Griffin and Co., Ltd., 1899.) TABLES for qualitative analysis are to be found in every chemical laboratory, and are used by every analyst at one time or another. Any attempt to supply chemists with information on quantitative analysis drawn up in the same convenient form must therefore be welcome. The present collection of tables has been carefully pre- pared, and is well arranged. It includes the analyses of iron ores, steel, limestone, boiler incrustation, certain slags, gaseous fuels, water, coal, and a few of the common metals and alloys. Alternative methods are not given, but the tables will be found very useful in saving the time of an analyst engaged in the examination of materials with which he is not accustomed to deal in the ordinary course of his daily work. LETTERS TO THE EDITOR. (Zhe Editor does not hold himself responsible for opinions ex- pressed by hts correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for this or any other part of NATURE. No notice ts taken of anonymous communications. ] Tides of the Gulf and River St. Lawrence and Bay of Fundy. PERMIT me to invite your attention to the latest report of the engineer in charge of the survey of the tides and currents of the coast waters of Canada, Mr. W. Bell Dawson, a copy of which has been addressed to you, This survey, commenced by the Government of Canada in 1894, is of great importance, not merely in the interest of hydrographical science, but of the large and increasing trade which finds its way along the gulf and river St. Lawrence, the greatest water-way from the North Atlantic into the northern part of the American continent, and which, like all 292 similar tide-ways, is affected by the complex action of the tides and consequent currents. It is much to be regretted that the economy or parsimony of the Government has caused a suspension for the present of the special survey of the currents, and has restricted the work to tidal observations, which, though of great value to the shipping interests, can only be considered as preliminary in regard to the investigation of the currents themselves, which lead to so many losses of property and life, and tend to high rates of insurance, injurious to the shipowners and merchants of Canada, and through them to those of an empire as a whole. The present report, in addition to what can be done with the insufficient grant allowed, in the matter of tide-gauges and tide- tables, has reference to the behaviour of the gigantic tides of the Bay of Fundy, when confined by the converging coasts at the head of the bay, and their relation to the smaller tides on the opposite side of the isthmus connecting Nova Scotia and New Brunswick at Bay Verte on the Gulf of St. Lawrence. These and the phenomena of the ‘‘ bore” at the head of the Bay of Fundy are here for the first time described, illustrated by maps and sections, and tabulated, and will be found of the greatest interest by all who desire information as to the exceptional tides of this region. J. W. Dawson. School Laboratory Plans. As one who has had the privilege of seeing Mr. Dymond’s excellent arrangement and outlay of money in his laboratory at Chelmsford, may I make a comment on his letter in your issue of July 13? I think the conditions of work in an average school laboratory show some points of difference from those in Mr. Dymond’s laboratory. Of course qualitative analysis is now confined to quite senior boys, who can be persuaded not to treat the subject as if they were working from a cookery book ; | but though owning no allegiance to the Science and Art Department, I believe that drawers and lockers are valuable, not only in relieving the general stock of the laboratory (very heavy for descriptive and quantitative work) of some smaller apparatus in constant use, but also in conferring a feeling of ownership, which induces some care and respect in a boy for his belongings. With snap-locks answering to one master key, and the lockers of each class bearing a label of a distinctive colour, they may be at once opened by the assistant before a class, so that there need be no keys to lose and no depredations on neighbouring lockers. Mr. Dymond’s objection to that most durable of woods—teak—or why it alone should be left in a dirty state, I do not understand. Admitting that in all but very elementary work some tuition in the way of lectures is necessary, a laboratory will generally possess a lecture room ; and where this is a separate room, I grudge the space usually given to a demonstrator’s table in the laboratory, because no large section of a practical class is ever doing the same experi- ment at the same time. Physics, again, is often involved in this question of arrangement in a school. since the two subjects may, | I think, with little detriment and great economy often have a common lecture room. Considering the prodigal waste of space often seen in laboratories, and the number now being built by public bodies, some further views on this subject ought to be of value. A. E. Munsy. Felsted School. Duties of Provincial Professors. NATURE THE article in your issue of July 13 upon ‘‘ The Duties of | Provincial Professors local university colleges. It insists none too strongly upon the * will be welcomed by all professors in | disadvantageous position they occupy with regard to the op- | portunity for the prosecution of original research, and the un- fortunate result of compelling our best students to complete their scientific education in Germany. It is not sufficiently recognised that the reputation of a uni- versity is advanced more by the contributions to science and literature produced by its staff than by the mere number of its students. Unfortunately, the staff of assistants in the university colleges is often totally inadequate to the work required, and the knowledge that their energies will be dissipated in elementary teaching, and no time given for continuing original investi- gation, is deterring men of really high academic distinction from accepting such appointments. The government of a local college is largely directed by business men, and the methods which ensure commercial success are hardly those best calcu- NO. 1552, VOL. 60] [JuLy 27, 1899 lated to further the interests of true education. Salvation lies apparently in the fact of Government inspection ; the Govern- ment grant is only given when the education is of an advanced university type ; and, judging from the tenor of the Treasury Minute, ‘‘ University Colleges, Great Britain—Grant in Aid,” the fullest recognition is given to those colleges which offer Opportunities for advanced work and research and can show an adequate educational equipment. “© A PROFESSOR.” July 23. IN the articles on ‘* The Duties of Provincial Professors,” it is stated: ‘‘ In such cases students . . . may be called on to give evidence against their professors.” This is almost in- credible, but, to my great astonishment, I learnt quite lately that the only possible alteration in the statement consistent with truth would be the substitution of the words ‘* have been ” for ‘may be.” The adoption of such a course must be fatal to good discipline in a college, and it leaves the members of the staff at the mercy of a few unruly and ignorant students whose disposition to learn may be small, though their capacity for agitation is great. From time to time students of this descrip- tion will be found in every college. Apart altogether from | these evils, there is another reason why the practice of allowing Students to give evidence against a professor is decidedly objectionable ; and that is, the lay members of the governing body of a provincial college are not likely to fully understand how incompetent the average pass student is to form an opinion as to the soundness of the teaching he receives. In the interests, not merely of the provincial colleges, but of higher education throughout the country, it is desirable that professors should not, for any except very grave reasons, and then only after a perfectly fair trial, be forced to resign their offices. 12% THE VREDE EB CTURE: THE WAVE THEORY OF LIGHT: ITS INFLUENCE ON MODERN PHysICS. UR era is distinguished from preceding ages by wonderful utilisation of natural forces ; man, that | weak and defenceless being, has been enabled by his genius to acquire an extraordinary power, and to bend to _his use those subtle yet dreadful agents whose very existence was unknown to our ancestors. This marvel- lous increase of his material power in modern times is due cnly to the patient and profound study of natural phenomena, to the exact knowledge of the laws that governed them, and to the skilful combining of their effects. But what is peculiarly instructive is the dispro- portion between the primitive phenomenon and the greatness of the effects which industry has drawn from it. Thus, those formidable engines, based on electricity or steam, grew neither from lightning nor the volcano ; they had their birth from scarcely perceptible phenomena which would have remained for ever hidden from the | vulgar eye, but that penetrating observers were able to recognise and appreciate. This humble origin of most of the great discoveries which are to-day a benefit to the 1 Besides the interest presented by a glance on the progress and the influence of optical science, this lecture offers the conclusions of a careful study on Newton's treatise of optics. It will be seen that the thought of the great physicist has been singularly altered by a sort of legendary inter- pretation developed in the elementary treatises where the emission-theory is expounded. In order to make the theory of fits clearer, the commentators have imagined to materialise the luminous molecule under the form of a rotating arrow offering now its head, now its side. This mode of exposi- tion has contributed to lead to the belief that the whole emission-theory was comprehended in this rather childish image. q Nowhere in his treatise does Newton give a mechanical illustration of the luminous molecule : be confines himself to the description of facts, and | sums them up in an empirical statement without any hypothetical explan- ation. Moreover, he denies the opinion that he raises any theory, though he holds occasionally as very probable the intervention of the waves excited in the ether. 7 So that the general impression resulting from the reading of the treatise and above all of the ‘“‘ queries” in the 3rd Book, is the following : Newton, far from being the adversary of the Cartesian system, as he is commonly repre- sented, looks, on the contrary, very favourably at the principles of this system. Struck by the resources which the undulatory hypothesis would offer for the explanation of the luminous phenomena, he would have adopted it, if the grave objection concerning the rectilinear propagation of light (only recently solved by Fresnel) had not prevented him. Jury 27, 1899] whole human race, shows us plainly that the scientific spirit is at present the mainspring of the life of nations, and that it isin the onward march of pure science that we are to look for the secret of the growing power of the modern world. Whence a series of questions which demand more and more the attentions of all. How did this taste towards the study of natural philosophy, so dear to the ancient philosophers, abandoned for centuries, again revive and grow? What are the phases of its advance? How appeared the new notions which have so deeply modified our ideas on the mechanism of nature’s forces? What paths, rich in discoveries, lead us gradually unawares to those admirable generalisations in accordance with the vast plan foreseen by the founders of modern physics? These are the questions which as a physicist I intend to inquire into before you. The sub- ject is rather abstract, I might say severe. But no other has seemed more worthy of your attention during the féte which the University of Cambridge celebrates to-day in honour of the Lucasian Professorship Jubilee of Sir Geo. Gabriel Stokes, who in his fine career has laid a master-hand on the very problems which seemed to me the most conducive to the progress of natural philosophy. The subject is all the more fitted here, as in citing the names of those great minds to whom modern science is most indebted, we found amongst those who most honoured the University of Cambridge—its Professors and Fellows—Sir Isaac Newton, Thomas Young, George Green, Sir George Airy, Lord Kelvin, Clerk Maxwell, Lord Rayleigh, and the memory of that glory which links to-day back through the centuries would add lustre to the present ceremony. Let us then, in a rapid glance of the scientific revival, point out the secret but mighty influence which has been the directing force of modern physics. I am inclined to attribute to the study of light, and to the attraction it has for the highest minds, one of the most effective causes of the return of ideas towards natural philosophy, and con- sider optics as having exercised on the advance of science an influence it would be difficult to exaggerate. This in- fluence, already clear at the dawn of the experimental philosophy under Galileo, grew so rapidly that to-day it is easy to foresee a vast synthesis of natural forces founded on the principles of the wave theory of light. This influence is easy to understand if we reflect that light is the way by which knowledge of the exterior world reaches our intelligence. It is, in fact, to sight that we owe the quickest and most perfect notions of the objects around us: our other senses, hearing, feeling, also bring their share of learning, but sight alone affords us abundant means of simultaneous information such as no other sense can. It is, therefore, not surprising that light. this lasting link between us and the outward world, should intervene with the varied sources of its inner constitution to render more precise the observation of natural phenomena. Thus each discovery concerning new properties of light has had an immediate effect on the other branches of human knowledge, and has indeed determined the birth of new sciences by affording new means of investigation of unexpected power and delicacy. Optics are really a modern science. The ancient philosophers had no idea of the complexity of what is vulgarly called light ; they confounded in the same name what is proper to man, and what is exterior. They had, however, perceived one of the characteristic properties of the link, which exists between the source of light and the eye, which receives the impression, “Light moves in a straight line.” Common experience had revealed this axiom through the observation of the shining trains that the sun throws across the skies, piercing misty clouds, or penetrating into some dark space. Hence arises two empirical notions—the definition of the ray of light, and that of the straight line. The one became the basis of optics, the other that of geometry. NO. 1552, VOL. 60] NATURE 293 Very little remains to us of the ancient books upon optics. Yet we are aware that they knew the reflection of the luminous rays on polished surfaces, and the geo- metrical explanation of the images formed by mirrors. We must wait many centuries until the scientific re- vival for a new progress in optics (but then a very con- siderable one) opens the new era; it is the invention of the telescope. The new era begins with Galileo, Boyle and Des- cartes, the founders of experimental philosophy. All devote their life to meditations on light, colours, and forces. Galileo lays the base of mechanics and with the refracting telescope that of astro-physics. Boyle im- proves experimentation. As to Descartes, he embraces with his penetrating mind the whole of natural philosophy; he throws away the occult causes admitted by the scholastics, and proclaims as a principle that all phe- nomena are governed by the laws of mechanics. In his system of the universe, light plays a prominent part! : it is produced by the waves excited in the subtle matter which, according to his view, pervades space. This subtle matter (which represents what we call to-day the ether) is considered by him as formed of particles in immediate contact ; it constitutes thus at the same time the vehicle of the forces existing between the material bodies which are plunged in it. We recognise the famous “vortices of Descartes,” sometimes admired, sometimes baffled during the last centuries, but to which skilful contemporaneous physicists have rendered the importance they deserve. Whatever may be the opinions granted to the exact- ness of the deductions of this great philosopher, we must be struck by the boldness with which he proclaims the connection of the great cosmical problems, and for- tells the solutions which actual generations did not yet entirely accept but drew insensibly to. In Descartes’ view the mechanism of light and that of gravitation are inseparable ; the seat of corresponding phenomena is this subtle matter which pervades the universe, and their propagation is performed by waves around the acting centres. This conception of the nature of light shocked the opinions in vogue; it raised strong opposition. Since the oldest times it was the habit to imagine the luminous ray as the trajectory of rapid projectiles thrown by the radiant source. Their shock on the nerves of the eye produce vision ; their resistance or changes of speed, reflection or refraction. The Cartesian theory had, how- ever, some seductive aspects which brought defenders. The waves excited on the surface of still water offer so clear an image of a propagated motion around a dis- turbing centre! On the other hand, do not the sonorous impressions reach our ear by waves? Our mind feels yet a real satisfaction in thinking that our most sharp and delicate organs are both impressed by a mechanism of the same nature. Yet a serious difference arose. Sound does not necessarily travel in straight lines as light does. It travels round any object opposed to it, and will follow the most circuitous routes with scarcely any loss of strength. Physicists were thus divided into two camps. In one the partisans of emission, in the other those of the wave theory, each system boasting itself superior, and indeed each being so in certain respects. Other phenomena had to be examined in order to decide between them. The chance of discovery brought to view several phenomena which ought to have decided in favour of wave theory, as was proved a century later ; but the simplest truth does not prevail without long endeavour. A strange compromise was effected between the two systems, helped on by a name great among the greatest, and for a century the theory of emission triumphed. The tale is a strange one. In 1661 a young scholar, 1 Le Monde de M. Descartes, ou le Traité de la Lumiére (Paris, 1664). 204 NATURE [JuLy 27, 1899 full of eagerness and penetration, enters Trinity | secretly tu find in the pure undulations the explanation of College, Cambridge; his name is Isaac Newton. | the beautiful phenomena he has reduced to such simple He has already in his village read Kepler's “Optics.” Almost immediately, and while following Barrow’s lectures upon optics, he studies the geometry of Descartes with passionate care; with his savings he buys a prism that he might examine the properties of colour and meditate deeply on the causes of gravitation. Eight years later his masters think him worthy to succeed Barrow in the Lucasian Professorship, and in his turn he also teaches optics. The pupil soon becomes greater than his teacher, and he gives out this great result : White light which seemed the type of pure light is not homo- geneous ; it consists of rays of different refrangibility, and he demonstrates it by the celebrated experiment of the solar spectrum, in which a ray of white light is de- composed into a series of coloured rays like a rainbow ; each shade of the colour is simple, for the prism does not decompose the shade. This is the origin of the spectral analysis. This analysis of white light brought Newton to explain the colours of the thin plates which are, for instance, observed in soap-bubbles. The funda- mental experiment, that of Newton’s rings, is one of the most instructive in optics, while the laws that govern it are of admirable simplicity. The theory was expounded in a discourse addressed to the Royal Society with the title, ““ A New Hypothesis concerning Light and Colour.” This discourse called forth from Hooke a sharp com- plaint. Hooke also had already examined the colour of thin plates, and endeavoured to explain them in the wave system. He had the merit, which Newton himself readily granted, to substitute for the progressive wave of Descartes a vibrating one—a new and extremely im- portant notion. He had even noticed the part of the two reflecting surfaces of the thin plate, and the mutual action of the reflected waves. Consequently Hooke should have been the very forerunner of the modern theory if he had had, as Newton, the clear intelligence of the simple rays. But his vague reasoning to explain the colours takes away all demonstrative value from his theory. Newton is very affected by this complaint of priority, and combats the arguments of his adversary by remark- ing that the wave theory is inadmissible because it does not explain the existence of the luminous ray and of the shadows. He denies the opinion that he has raised a theory ; he certifies that he does not admit either the wave hypothesis or the emission, but he says “ He shall sometimes, to avoid circumlocution and to represent it conveniently, speak of it as if he assumed it and pro- pounded it to be believed.” And, really, in the Proposi- tion XII. (second book of his Optics),! which constitutes what was since called the theory of fits, Newton remains absolutely on the ground of facts. He says simply, the phenomena of thin plates prove that the luminous ray is put alternatively in a certain state or fit of easy re- flexion and of easy transmission. He adds, however, that if an explanation of these alternative states is re- quired they can be attributed to the vibrations excited by the shock of the corpuscles, and propagated under the form of a wave in ether.” After all, notwithstanding his desire to remain on the firm ground of facts, Newton cannot help trying a rational explanation. He has too carefully read the writings of Descartes not to be heartily, as Huygens, a partisan of the universal mechanism and not to wish 1 Prop. XII.—LHvery Ray of Light in its passage through any refracting Surface is put into a certain transient constitution or state, which in the progress of the Ray returns at equal Intervals, and disposes the Ray at every return to be easily transmitted through the next refracting Surface, and between the returns to be easily reflected by it. (Sir Isaac Newton, “ Opticks: or a Treatise of the Reflections, Refractions, Inflexions and plows of Light." London, 1718. Second edition, with additions. P. 293. ~ Loc. cit., p. NO. 1552, VOL. 60] laws. But his third bock on optics more especially proves his Cartesian aspirations, and, above all, his per- plexity. His famous “ Queries” expose so forcibly his argument in favour of the wave theory of light that Thos. Young will later cite them as proof of the final conversion of Newton to the wave theory. Newton would certainly have yielded to this secret inclination had the inflexible logic of his mind allowed him to do so; but when after enumerating the arguments the wave theory of light offers in explanation of the intimate nature of light, when he arrived at the last “queries” he stops, as if seized by a sudden remorse, and throws it away. And the sole argu- ment is that he does not see the possibility of explaining the rectilinear transmission of light.!. Viewed from this standpoint the third book of Ofécks is no longer only an 1 First, here is an extract from the ‘‘ Queries” which prove the leaning of Newton's views towards the undulatory theory and the Cartesian ideas. ““ Query 12.—Do not the Rays of light in falling upon the bottom of the eye excite Vibrations in the 7znica Retina ? Which Vibrations, being pro- pagated along the Solid Fibres of the optick nerves into the brain, cause the Sense of seeing. . .” “ Query 13.—Do not several sorts of Rays make Vibrations of several big- nesses, which, according to their bignesses, excite sensations of several colours, much after the manner that the vibrations of the air, according to- their several bignesses, excite sensation of several sounds? And particularly do not the most refrangible rays excite the shortest vibrations for making a sensation of deep violet, the least refrangible the largest for making a sensation of deep red, &c.?...” “Query 18.— .. . Isnotthe heat of the warm room conyey’d through the vacuum by the vibrations of a much subtiler medium than air, which, after the air was drawn out remained in the vacuz? [ether] and is not this medium the same with that medium by which light is refracted and reflected, and by whose vibrations light communicates heat to bodies, and is put into« fits of easy reflection and easy transmission? ... And is not this medium exceedingly more rare and subtile than the air, and exceedingly more elastic and active? and doth it not readily pervade all bodies? and is it not (by its elastick force) expanded through all the heavens?” Newton, afterwards, considers the possible connection of this medium (ether) with the gravitation and the transmission of the sensations and motion in living creatures (queries 19 to 24). The dissymetrical properties of the two rays propagated in the Iceland spar, draw equally his attention (query 25 to 20). Here appears this sudden and unexpected going back. this sort of remorse from having too kindly expounded the resources of the Cartesian theory, based on the Ader22 ; he makes an apology as follows : “Query 27.—Are not all hypotheses erroneous which have hitherto been “Query 28.—Are not all hypotheses erroneous in which light is supposed to consist in pression or motion, propagated through a fluid medium?.. . and if it (light) consisted in pression or motion, propagated either in an instant or in time, it would bend into shadow. For pression or motion cannot be propagated in a fluid in right lines beyond an obstacle, which stops part of the motion, but will bend and spread every way into the quiescent medium which lies beyond the obstacle... . For a bell or a canon may be heard beyond a hill which intercept the light of sounding body, and sounds are propagated as readily through crooked pipes as through straight ones. But light is never known to follow crooked passages nor to bend into the shadow. . . .” Stopping before this objection Newton is forced to come back to the corpuscular theory. ‘Query 29.—Are not the rays of light very small bodies emitted from shining substances? . . .” * Query 30.—Are not gross bodies and light convertible into one another ...? The changing of bodies into light and light into bodies, is very con- formable to the course of nature, which seems delighted with transmuta- tlOUS.9% re: Logic urges him to go on with the old hypothesis of the vacwum and atoms, and even to invoke the authority of the Greek and Pheenician philosophers in this matter (query 28, p. 343), therefore it is not surprising to see his perplexity expressed by the following words :— “Query 31, and the last.—Have not the small particles of bodies certain powers, virtues, or forces, by which they act at a distance not only upon the rays of light for reflecting, refracting and inflecting them, but also upon one another for producing a great part of the phenomena of nature? .. .” But he perceives that he is going rather far, and compromising himself, therefore his secret tendency, developed in the foremost queries, reappear a little while :-— ‘ ««. . . How these attractions may be performed I do not here consider. What I call attraction may be perform’d by impulse, or by some other means unknown tome...” Many other curious remarks could be made on the state of mind of the great physicist, geometer and philosopher, which is artlessly revealed in those ‘‘ queries.” The preceding short extracts are sufficient, I believe, to justify the conclusion which I get from the study of the 3rd Book, namely, that Newton had not at all on the mechanism of light the definite ideas which have been attributed to him as founder of the emission-theory. Really, he is hesitating between the two opposite systems, perceiving clearly their insufficiency ; and in this discussion he is endeavouring to go away as little as possible. from the facts. That is the reason for which he has stated no dogmatic theory. {[t would be, therefore, unjust to make Newton responsible for every consequence which the emission partisans have sheltered under his authority. JuLy 27, 1899] NATURE 295 impartial discussion of opposite systems ; it appears as the painting of the suffering of a mighty genius, worried by doubt, now led away by the seductive suggestions of his imagination, now recalled by the imperious require- ments of logic. It is a drama: the everlasting struggle between love and duty ; and duty won. Such, I take it, is the inner genesis of the theory of fits—a strange mingling of two opposite systems, It was much admired, presented, as it was, by the great mathematician, who had the glory of submitting the motions of all celestial bodies to the one law of universal gravitation. To-day this theory is abandoned ; it is condemned by the experimentum crucis of Arago, realised by Fizeau and Foucault. One ought, however, to acknowledge that it has constituted a real progress by the precise and new notions which it contains. ‘The ray of light, considered up till then, was simply the trajectory of a particle in rectilinear motion ; the ray of light, such as Newton de- scribed it, possesses a regular periodic structure, and the period or interval of fits, characterises the colour of the vay. This is an important result. It only requires a more suitable interpretation to transform the luminous ray into a vibratory wave; but we had to wait a century, and Dr. Thomas Young, in 1801, had the honour of discovering it. Resuming the study of thin plates, Thomas Young shows that everything is explained with extreme sim- plicity, if it be supposed that the homogeneous luminous ray is analogous to the sonorous wave produced by a musical sound; that the vibrations of ether ought to compose—that is to say, to interfere—according to the expression that he proposes as to their mutual actions. Although Young had taken the clever precaution of supporting his views by the authority of Newton,! the hypothesis found no favour ; his principle of interference led to this singular result that light added to light could, in certain cases, produce darkness, ag paradoxical result contradicted by daily experience. The only verification that Young brought forward was the existence of dark rings in Newton’s experiment, darkness due, according to him, to the interference of waves reflected on the two faces of the plate. But as the Newtonian theory inter- preted the fact in a different manner, the proof remained doubtful ; an experimentum crucis was wanting. Young did not have the good success to obtain it. The theory of waves relapsed then once more into the obscurity of controversy, and the terrible argument of the rectilinear propagation was raised afresh against it. The most skilled geometers of the period—Laplace, Biot, Poisson—naturally leaned to the Newtonian opinion ; Laplace in particular, the celebrated author of the ““ Mecanique Celeste,” had even taken the offensive. He was going to attack the theory of waves in its most strongly fortified entrenchments, which had been raised by the illustrious Huygens. Huygens, indeed, in his “‘ Traité de la Lumiére,” had resolved a problem before which the theory of emission had remained mute ; that is to say, the explanation of the double refraction of Iceland spar: the wave theory (on the contrary) reduced to the simplest geometrical construction the path of the two rays, ordinary and extra- ordinary ; experiment confirmed the results in every point. Laplace succeeded in his turn (with the help of hypotheses of the constitution of luminous particles) to ex- plain the path of these strange rays. The victory of the theory of particles then appeared complete; a new phenomenon arrived also appropriately to render it striking. Malus discovered that a common ray of light reflected under a certain angle acquired unsymmetrical properties similar to those rays from a crystal of Iceland spar. He 1 The Bakerian Lecture, ‘‘On the Theory of Light and Colours.” By Thomas Young. PAzl. Trans. of the R.S. for the year 1802. NO. 1552, VOL. 60] explained this phenomenon by an orientation of the luminous molecule, and, consequently, named this light polarised light. This was a new success for emission. The triumph was not of long duration. In 1816 a young engineer, scarcely out of the Ecole Polytechnique, Augustin Fresnel, confided to Arago his doubts on the theory then in favour, and pointed out to him the experi- ments which tended to overthrow it. Supporting himself on the ideas of Huygens, he attacked the formidable question of rays and shadows, and had resolved it: all the phenomena of diffraction were reduced to an analytical problem, and observations verified calculation marvellously. He had, without know- ing it, rediscovered Young’s reasonings as well as the principle of interference ; but more fortunate than he, he brought the experdmentum crucis—the two-mirror experiment; there, two rays, issuing from the same source, free from any disturbance, produced when they met, sometimes light, sometimes darkness. The illus- trious Young was the first to applaud the success of his young rival, and showed him a kindness which never changed. Thus, thanks to the use of two-mirror experiment, the theory of Dr. Young (that is to say, the complete analogy of the luminous ray and the sound wave) is firmly established. Moreover, Fresnel’s theory of diffraction shows the cause of their dissimilarity; light is propagated in straight lines because the luminous waves are extremely small. On the contrary, sound is diffused because the lengths of the sonorous waves are relatively very great. Thus vanished the terrible objection which had so much tormented the mind of great Newton. But there remained still to explain another essential difference between the luminous wave and the sonorous wave ; the latter undergoes no polarisation. Why is the luminous wave polarised ? The answer to this question appeared so difficult that Young declared he would renounce seeking it. Fresnel worked more than five years to discover it ; the answer is as simple as unexpected. The sound wave cannot be polarised because the vibrations are longitudinal ; light, on the other hand, can be polarised because the vibra- tions are transverse, that is to say, perpendicular to the luminous ray. Henceforth the nature of light is completely estab- lished, all the phenomena presented as objections to the undulatory theory are explained with marvellous facility, even down to the smallest details. I would fain have traced by what an admirable suite of experiment and reasoning Fresnel arrived at this dis- covery, one of the most important of modern science : but time presses. It has sufficed me to explain how very great the difficulties were which he had to overcome in order to establish it. I hasten to point out its consequences. You saw, at starting, the purely physiological reasons which make the study of light the necessary centre of information gathered by human intelligence. You judge now, by the march of this long development of optical theories, what preoccupations it has always caused to powerful minds interested in natural forces. Indeed, all the phenomena which pass before our eyes involve a transmission to a distance of force or movement ; let the distance be infinitely great, as in celestial space, or infinitely small, as in molecular intervals, the mystery is the same. But light is the agent which brings us the movement of luminous bodies ; to fathom the mechanism of this transmission is to fathom that of all others, and Descartes had the admirable intuition of this when he comprehended all these problems in a single mechanical conception: here is the secret bond which has always attracted the physicists and geometers towards the study 296 NATURE [Jury 27, 189y of light. Looked at from this point of view, the history of optics acquires a considerable philosophical import- ance ; it becomes the history of the successive progress of our knowledge on the means that nature employs to transmit movement and force to a distance. The first idea which came to the mind of man (in the savage state) to exercise his force beyond his reach is the throwing of a stone, of an arrow or of some projec- tile ; this is the germ of the theory of emission. This theory corresponds to a philosophical system which assumes an empty space in which the projectile moves freely. At a more advanced degree of culture, man having becomea physicist, has had the more delicate idea of the transmission of movement by waves, suggested at first by the study of waves, afterwards by that of sound. This second way supposes, on the other hand, that space is a plenum ; there is no longer here transport of matter ; particles oscillate in the direction of propagation, and it is by compression or rarefaction of a continuous elastic medium that movement and force are trans- mitted. Such has been the origin of the theory of luminous waves ; under this form it could only represent a part of the phenomena ; it was therefore insufficient. But geometers and physicists before Fresnel did not know of any other undulatory mechanism in a continuous medium. The great discovery of Fresnel has been to reveal a third mode of transmission quite as natural as the pre- ceding one, but which offers an incomparable richness of resources. These are the waves of transverse vibrations excited in an incompressible continuous medium, those which explain all the properties of light. In this undulatory mode the displacement of particles brings into play an elasticity of a special kind; this is the relative slipping of strata concentric to the disturb- ance which transmits the movement and the effort. The character of these waves is to impose on the medium no variation of density as in the system of Descartes. The richness of resource mentioned above depends upon the fact that the form of the transverse vibration remains indeterminate, and thus confers on waves an infinite variety of different properties. The rectilinear, circular and elliptical forms characterise precisely the polarisations, so unexpected, which Fresnel discovered, and by the aid of which he has so admirably explained the beautiful phenomena of Arago produced by crystallised plates. The possible existence of waves which are propagated without change of density, has profoundly modified the mathematical theory of elasticity. Geometers found again in their equations, waves having transverse vibra- tions which were unknown to them ; they learnt besides, from Fresnel, the most general constitution of elastic media, of which they had not dreamt. It is in his admirable memoir on double refraction that this great physicist set forth the idea that in crystals the elasticity of the ether, ought to vary with the direction, an unexpected condition and one of extreme importance, which has transformed the fundamental bases of mole- cular mechanics ; the works of Cauchy and Green are the striking proofs of it. From this principle Fresnel concluded the most general form of the surface of the luminous wave in crystals, and found (as a particular case) the sphere and ellipsoid that Huygens had assigned to the Iceland spar crystal. This new discovery excited universal admiration among physicists and geometers ; when Arago came to expound it before the Académie des Sciences, Laplace, who had been such a long time hostile, declared himself convinced. Two years later Fresnel, unanimously elected a member of the Academy, was elected with the same unanimity foreign member of the Royal Society of London ; Young himself transmitted to him the announcement of this distinction, with personal testimony of his sincere admiration. NO. 1552, VOL. 60] The definite foundation of the undulatory theory im- poses the necessity of admitting the existence of an elastic medium to transmit the luminous movement. But does not all transmission to a distance of movement or of force imply the same condition? To Faraday is due the honour of having, like a true disciple of Descartes and Leibnitz, proclaimed this principle, and of having resolutely attributed to reactions of surrounding media the apparent action at a distance of electrical and mag- netic systems. Faraday was recompensed for his bold- ness by the discovery of induction. And since induction acts even across a space void of ponderable matter, one is forced to admit that the active medium is precisely that which transmits the luminous waves, the ether. The transmission of a movement by an elastic medium cannot be instantaneous ; if it is truly luminous ether that is the transmitting medium, ought not the induction to be propagated with the velocity of luminous waves ? The verification was difficult. Von Helmholtz, who tried the direct measurement of this velocity, found, as Galileo formerly, for the velocity of light a value practically infinite. But the attention of physicists was attracted by a singular numerical coincidence. The relation between the unity of electrostatic quantity to the electro-magnetic unit is represented by a number precisely equal to the velocity of light. The illustrious Clerk Maxwell, following the ideas of Faraday, did not hesitate to see in the relationship the indirect measure of the velocity of induction, and by a series of remarkable deductions he built up this cele- brated electro-magnetic theory of light, which identifies in one mechanism three groups of phenomena completely distinct in appearance, light, electricity, and magnetism. But the abstract theories of natural phenomena are nothing without the control of experiment. The theory of Maxwell was submitted to proof, and the success surpassed all expectation. The results are too recent and too well known, especially here, for it to be necessary to insist upon them. A young German physicist, Henry Herz, prematurely lost to science, starting from the beautiful analysis of oscillatory discharges of Von Helmholtz and Lord Kelvin, so perfectly produced electric and electro-magnetic waves, that these waves possess all the properties of luminous waves ; the only distinguishing peculiarity is that their vibrations are less rapid than those of light. It follows that one can reproduce with electric dis- charges the most delicate experiments of modern optics —reflection, refraction, diffraction, rectilinear, circular. elliptic polarisation, &c.. But I must stop, gentlemen. I feel that I have assumed too weighty a task in en- deavouring to enumerate the whole wealth which waves of transverse vibrations have to-day placed in our hands. I said at the beginning that optics appeared to me to be the directing science in modern physics. If any doubt can have arisen in your minds, I trust this impression has been effaced to give place to a sentiment of surprise and admiration in seeing all that the study of light has brought of new ideas on the mechanism of the forces of nature. It has insensibly restored the Cartesian conception of a single medium refilling space, the seat of electrical, magnetic and luminous phenomena ; it allows us to fore- see that this medium is the depositary of the energy spread throughout the material world, the necessary vehicle of every force, the origin even of universal gravitation. : Such is the work accomplished by optics : the greatest thing of the century ! The study of the properties of waves, viewed in every aspect, 1s therefore, at the present moment, the most fertile study. it is perhaps JuLy 27, 1899| NATURE 297 It is that which has been followed in the double capacity of geometer and physicist by Sir George Stokes, to whom we are about to pay so touching and deserved ahomage. All his beautiful researches, both in hydro- dynamics as well as in theoretical and practical optics, relate precisely to those transformations which various media impose on waves which traverse them. In the many phenomena which he has discovered or analysed, movements of fluids, diffraction, interference, fluorescence, Réntgen rays, the dominant idea which I pointed out to you is always visible; it is that which makes the harmonious unity of the scientific life of Sir George Stokes. The University of Cambridge may be proud of the Lucasian Chair of Mathematical Physics, because from Sir Isaac Newton up to Sir George Stokes it has con- tributed a glorious part towards the progress of Natural Philosophy ! A. CORNU. NOTES. WE are glad to be able to publish this week a translation of the Rede Lecture delivered at Cambridge by Prof. Alfred Cornu, professor of experimental physics in the Ecole polytech- nique, Paris, and a Foreign Member of the Royal Society, on the occasion of the recent celebration of the jubilee of Sir George Stokes as Lucasian professor of mathematical physics. Prof. Cornu delivered the lecture in French, and we are indebted to him for the translation of his brilliant discourse, which immediately precedes this Note. AN interesting gathering took place at the Star and Garter Hotel, Richmond, on Thursday last, when a number of friends joined with the members of the Physiological Society in giving a congratulatory dinner to Sir John Burdon-Sanderson, Bart., F.R.S., and Prof. Michael Foster, K.C.B., Sec. R.S., in honour of Her Majesty’s recent recognition of the great services they have rendered to science. The chair was taken by Prof. Schafer, F.R.S., and the friends who assembled to support him in doing honour to the distinguished guests numbered consider- ably over a hundred. The principal speeches of the evening were made by the chairman, by Sir John Burdon-Sanderson, and by Prof. Michael Foster, all of whom were able to give interesting reminiscences of the early days of physiology in England, and of the great difficulties which used to be thrown in the way of those who wished to study the subject. Owing to the exigencies of the various examinations now in progress, many physiologists were unable to be present in the earlier part of the evening, but the great interest taken in the proceedings was shown by the long journeys undertaken by several in order that they might take part at the dinner. THE special number of the 4/72, containing the report of the anniversary meeting of the Reale Accademia dei Lincei, announces the annual awards of prizes. The Royal prize for astronomy for 1896 remains unawarded. The Royal prize for philology and languages is divided equally between Prof. Pio Rajna, for his critical edition of Dante’s ‘De Vulgari Eloquentia,” and Prof. Claudio Giacomino, for his studies on the Basque language. The prize for history and geography is unawarded, and the same is true of a prize offered for 1898 for perfecting the theory of motion of a rigid body. The Ministerial prize of 3400 lire for history for 1898 is divided, a prize of 1700 lire being awarded to Prof. Gaetano Salvemini, and smaller awards being made to Profs. Alberto Pirro, Niccolé Rodolico, and Michele Rosi. Of the Ministerial prize of 3400 lire for mathematics for 1898, a prize of 2000 lire is awarded to Prof. Ettore Bortolotti, and awards of 700 lire each are made to Profs. Federico Amodeo and Francesco Palatini. The adjudicators state that the works of Prof. Pirondini would have NO. 1552, VOL. 60] gained an award had not some of them received recognition on a previous occasion. The adjudicators of the Ministerial prize for philosophical and social sciences for 1897 award 500 lire each to Profs. Albino Nagy, Luigi Ambrosi, and Tarozzi. The Mantellini prize is unawarded, Of the Santoro prize for electro-technics one half is awarded to Signor R. Arno, for his share in the joint invention with the late Prof. G. Ferraris of a new transformer. The Santoro prize for chemistry as applied to agriculture is unawarded, and from the Carpi prize for mathematical physics for 1897-8 a sum of 500 lire is awarded to Signor C. Canovetti, for his papers on the direction of aerostats and on the resistance of the air. IN connection with the preparation of argon, a good deal of attention has been paid to the absorption of nitrogen by metals. Prof. Ramsay, it will be remembered, used magnesium. Later, lithium was proposed by Ouvrard, and a mixture of lime and magnesium by Maquenne. The subject has recently been systematically investigated by Dr. Hempel, who finds that a mixture of calcium magnesium and sodium is very much more effective than the agents just named. The mixture is obtained by using 1 gramme of finely divided magnesium, 5 grammes coarsely powdered lime, and 0°25 grammes sodium. In a com- parative time experiment the rates of absorption of nitrogen by magnesium, lithium, lime-magnesium, and lime-magnesium- sodium were in the ratio 1, 5, 8 and 20. To commemorate the completion of the twenty-five years of active work as a teacher of physiology of Prof. Purser, of Trinity College, Dublin, a movement is on foot among the professor’s former pupils to raise funds for the bestowment annually of a “Purser Medal” to the candidate who, in the half M.B. examination, shows the highest proficiency in physiology and histology. Subscriptions, which are not to exceed a guinea, should be forwarded to the honorary treasurer, Dr. W. J. Houghton, 30 Lower Fitzwilliam Street, Dublin. Dr. MaxweELt T. MasTERs, F.R.S., has been made an officer of the Order of Leopold by the King of the Belgians. THE Neill Prize for 1895-98 has been awarded to Prof. J. Cossar Ewart, F.R.S., by the Royal Society, Edinburgh, for his experiments and investigations bearing on the theory of heredity. THE King of Sweden has conferred upon Mr. E. P. Martin, past-President of the Iron and Steel Institute, a Knight-com- mandership of the Royal Order of Wasa, and upon Mr. Bennett H. Brough, present Secretary of the Institute, a Knighthood of the same Order. A DEPUTATION from the Iron and Steel Institute, consisting of Sir W. C. Roberts-Austen, K.C.B., F.R.S., President, Sir Lowthian Bell, Bart., F.R.S., Mr. E. P. Martin, past- Presidents, and Mr. Bennett H. Brough, Secretary, waited upon the Queen last week for the purpose of presenting to Her Majesty an illuminated address and the Bessemer Gold Medal, in commemoration of the great progress made in the iron and steel trade during the Queen’s reign. Tue Meteorological Council have appointed Captain Campbelt M. Hepworth, R.N.R., to fill the post of Marine Superintendent in succession to the late Mr. Baillie. Captain Hepworth has been an observer for the Meteorological Office for twenty-three years, and almost all of his logs haye been classed “‘ excellent.” A MEETING of the Aeronautical Society will be held at the Society of Arts to-morrow (July 28) at eight p.m. THE summer meeting of the Institution of Mechanical Engineers was opened at Plymouth on Tuesday. In connection 298 swith the meeting the Freedom of the Borough of Devonport has been presented to the president, Sir W. H. White, K.C.B., F.R.S. THE thirty-sixth annual conference of the British Pharma- 1 B= "(Bi J (e"—u . u—e) +2Bo/(e’ - oy V2 where the A’s and B’s are rational polynominals of z. Thus for 7=5, we can take of 2c peGassaes es 1 Pym: 7 Wao re “2 7 Wt. NI GEria 4c JC=1 where C= aera; and Ae Daa A, = Pre SP pee eos ESS 1S el mala ocr T)(c— ae Aucust 10, 1899] NATURE 349 §ci trict +26c3 —10c* +e -1 2c8(e+ 13(c— 1)* _ch—10c8+2c2—2c+1 , e#(c+1)3(c— 1)? Pj= B,=Qu+Qr where : oaer3le=4c— 0) poe. 47 fs “~~ ack(e+1)(e-1) (C= 4¢-1) (5c? +2c+1) chaz 52 ano 2ck(¢ +1) (¢-1)? Stig +7e+1 , — 238 +227+1oct+2 Cr») B,=72=9 = ra e(e + 1)*(e— 1) The same functions a, 8, y, 5, and their special alge- braical forms are suitable for Kirchoff’s case of the motion of a solid in infinite liquid, but now V is a quartic function of z, requiring resolution into factors. In the more general case invented by Clebsch, and developed in Halphen’s ‘“ Fonctions elliptiques,” t. II., the component rotation about OZ is no longer con- stant, and the solution is more complicated, introducing multiplicative elliptic functions to a parameter corre- | sponding to the infinite value of z. If the motion of the axis of the top is alone required, we take A =oo, and investigate the function A = a/y; this is a multiplicative elliptic function, with an effective parameter a—4é, which can be made algebraical when a— is made an aliquot part of o’, irrespective of the separate terms @ and #. - By a further restriction, the exponential function of the time can be made to dis- appear, by making 7 +/'=0, and then H is at L in Fig. 1; it was inthis way that the analysis was prepared of the algebraical cases, represented stereoscopically by Mr. T. I. Dewar, referred to on p. 199. The authors say they have refrained from utilising these stereoscopic diagrams, because they would not like to assume in the reader the possession of a stereo- scope. But our eyes should be drilled into control to pick up the solid appearance without any apparatus ; a little quiet practice will suffice. Treatises on Solid Geometry of the future should be profusely illustrated with stereoscopic figures, which the student should see | solid at will; and wall diagrams or lantern projections should also be drawn stereoscopically, and the solid effect obtained in the audience by crossing the two lines of sight. Mr. T. I. Dewar’s untimely death, at San Remo last May, has deprived us of any further diagrams from his skill, but the example he set will we trust be followed out completely in mathematical diagrammatic instruction. The unsymmetrical top, discussed in V. § 9, leads into such great analytical complication, that only a few special degenerate cases have so far received any ade- quate attention ; the next century will have its work cut out for the mathematical treatment of this problem and also of the dynamics of the bicycle. The symmetrical top of the boy, with the point free to wander over a smooth or rough horizontal plane, leads to similar analytical difficulties, and should be discussed in the same place. On the other hand, the many attempts at a popular explanation of the motion of the top, restricted princi- | pally to the case of regular precession, are described in V. § 3. Prof. Perry’s interesting little book on “Spin- ning Tops” comes in for praise, and the authors cite with pleasure the comparison of the top to a wilful beast (eigensinniger thier), always ready to move in some other direction to that in which it is pushed ; insomuch that the Irishman can persuade his pig to accompany him on the road only by pretending that his way lies in the opposite direction ; and so Bessemer’s invention to steady the NO. 1554, VOL. 69] motion of a cabin mounted on gimbals, by means of the controlling influence of gyrostats, was a failure. If the authors are in search of other practical elemen- tary illustrations, they should take the modern centrifugal machine, and examine the practical devices, as in the Weston machine, for controlling the nutations ; these devices discovered experimentally without any assistance from theory will serve to elucidate the abstract formulas with advantage. A third part of this book is still to appear, and we await it with great interest ; the work when complete will form an indispensable book of reference for all who wish to make themselves thoroughly acquainted ‘with this: complicated problem in Dynamics. A. G. GREENHILL. NOTES. Av Osborne, on Wednesday, August 2, the Queen conferred the honour of knighthood upon Sir William Henry Preece and Sir Michael Foster, Knight Commanders of the Order of the Bath, and invested them with the riband and badge of the | Civil Division of the Second Class of the Order, and affixed the star to their left breasts. Tue Hanbury Gold Medal of the Pharmaceutical Society of Great Britain has been awarded to Prof. Albert Ladenburg, of Breslau, for his work on alkaloids and their derivatives. Mr. J. S. BupceErt, of Trinity College, Cambridge, who accompanied Mr. Graham Kerr on his expedition in search of Lepidosiren, has been successful in obtaining eggs and larvee of the Crossopterygian Ganoid Polypterus. From a short account of his investigations, illustrated by sketches, which Mr. Budgett has sent to this country, it appears that the larva is very minute, and possesses a ‘‘cement organ” on the dorsal surface of the head. Mr. Budgett is now on the journey home, and the full account of his work will be looked forward to with much interest. ON a preceding page we have referred to some of the work performed by the Royal Gardens, Kew. Coincidently we have received the number for July 21 of our American contemporary Science, which containsan elaborate article by Prof. Underwood, headed ‘‘ The Royal Botanic Gardens at Kew,” in which the features of the garden and its position as a scientific institution —‘‘its beautiful lawns, its delightful shade, its historic asso- ciations, its immense collections of cultivated plants, and_its wonderful activity in the direction of botanical research ”—are described and discussed with critical appreciation apropos the recent establishment of the Botanic Garden of New York and its capability to become ‘‘even more influential in democratic America than. Kew has become throughout the length and breadth of the Queen’s dominions.” It is gratifying to have this acknowledgment of the work of Kew ; and the tribute paid to the versatility and ability of Sir William Thiselton-Dyer in promoting its development and widening its influence will be everywhere endorsed. There are some blots on the escutcheon in the eyes of Prof. Underwood, but we imagine there are many who will not see with him in all the instances he mentions. The crowding of the museum collections he notes isan apparent blemish, and one we may hope to see removed by the provision of increased room for the exhibition of the specimens. A some- what jealous comparison of Kew and Berlin as centres of botanical work is a jarring note in the article; and Prof. Underwood allows, we fear, German bias to weigh with him in making it, for instance, when he writes, ‘‘ the principles of plant distribution are not so thoroughly grasped at Kew as they have been brought out at the German Botanical Garden through the skill of Prof. Engler and his associates.” Yet Kew is the home of Sir Joseph Hooker ! 30° NALORE For several years the need of greater facilities for the public- ation of mathematical investigations has been strongly felt by the members of the American Mathematical Society. This Society has maintained during the past eight years an historical and critical review, known as the Azd/etin of the American Mathematical Society, and throughout the whole of this period there has been a constantly growing demand for the publication in the pages of that journal of articles not properly falling within its scope. The co-operation of several American colleges and universities was therefore recently invited in a plan whereby such articles may be afforded suitable means of publication. The necessary co-operation has now been secured, and the publication of a quarterly number of the Zyazsactzons of the American Mathematical Society has been definjtely undertaken to begin January 1, 1900. The Zyazsactzons will be devoted primarily to research in pure and applied mathematics. The editors will welcome all papers containing investigations of sufficient mathematical interest and value. Such papers, in many cases, will be necessarily of considerable length ; but the editors will be very glad to receive, also, short contributions which are of such a character as to fall within the scope of the Transactions. Papers from mathematicians not belonging to the Society will be welcomed; such papers, if accepted for publication, will be presented to the Society by the editors. Manuscripts intended for publication in the 7yazsactzons should be addressed either to Prof. E. H. Moore, University of Chicago, Chicago, IIl., or to Prof. E. W. Brown, Haverford College, Haverford, Pa., or to Prof. T. S. Fiske, Columbia University, New York, N.Y. By the will of the late Dr. Jules Maringer, the Pasteur Institute at Paris is bequeathed the sum of one hundred thousand francs. THE death is announced at Olten, Switzerland, of M. N. Rieggenbach, Correspondant of the Paris Academy of Sciences, in the Section of Mechanics. Scéence announces the death of Mrs. Elizabeth Thompson, of Stamford, Conn., who made many gifts for benevolent and scientific purposes. She contributed towards the telescope for Vassar College, was one of three ‘* patrons” of the American Association for the Advancement of Science, and endowed the Elizabeth Thompson Science Fund, the income of which is now being so advantageously used for the promotion of scientific research. A REvTER despatch from St. Petersburg, dated August 2, says: — ‘‘News has been received here that the Russian members of the Russo-Swedish Scientific Expedition to Spits- bergen have arrived safely at Horn Sound, where they will winter. Later on they will proceed by land to the western side of the Stor Fiord, where they will engage in geodetic work. Some of the members will not remain over the winter, return- ing to St. Petersburg in October, but the others will stay in Spitsbergen until the autumn of next year. The Russian members of the expedition have not yet met with their Swedish colleagues; but Prof. Baklund has gone to meet them on board an ice-breaker.” REFERRING to the progress of vaccination, Mr. Chaplin said, in the House of Commons on Thursday last, that the returns which he had obtained showed that the total number of certificates of successful primary vaccination received by the vaccination officers during the first six months of the present year was 353,992 as against 277,821 in the first six months of 1898 ; that is to say, there has been an increase of upwards of 76,000 primary vaccinations or of more than 27 per cent. in the first six months of the present year as compared with the corre- sponding period of 1898. These results have been obtained in the first six months of the Act, notwithstanding the difficulty of NO. 1554, VOL. 60] [AucustT 10, 1899 giving effect to an entire change of method throughout the country from stational to domiciliary vaccination ; and also in spite of the fact that in numerous cases there was very con- siderable delay in the fixing of fees and the appointment of officers. From a note in the Zmes we learn that the section of the famous mpundu tree at Chitambo’s, which marked the place where Dr. Livingstone died, has been successfully removed by Mr. Codrington, the Deputy-Administrator of Northern Rhodesia, and will be sent to England for preservation. It will be remembered that two or three years ago Mr. Poulett Weatherley, while exploring in the neighbourhood of Lake Bangweolo, visited Chitambo’s and reported that the mpundu tree was in an advanced stage of decay and would probably disappear altogether ina very short time. After careful con- sideration, the Royal Geographical Society decided that the best course to pursue would be to cut out the section of the tree which bears the inscription and have it sent over to London for preservation at the rooms of the Society. To mark the place where the tree stood, a large cairn has been erected with a staff made of two telegraph poles in the centre, held in place by stays of telegraph wire. This temporary memorial will serve the purpose of preserving the identity of Dr. Livingstone’s deathplace until such time as a more permanent memorial is erected. THE sixth international otological congress was opened on Tuesday at the Examination Hall, Victoria Embankment. Prof. U. Pritchard, the. president-elect, was in the chair, and about three hundred aural surgeons from many parts of the world were present. In his presidential address, Prof. Pritchard traced the birth and growth of otological science. Although an ancient Egyptian papyrus had been found on which was written a monograph on deafness and ear diseases, otology, except perhaps with regard to its anatomy and physiology, did not make itself of great importance until the second half of the present century. Between 1840 and 1860 this branch of medical science was vigorously taken up by Sir William Wilde and Toynbee. Since then the means of diagnosis have been considerably improved, while in treat~ ment there has been immense strides, due to the adoption of antiseptic surgery. At the commencement of the present century the ear was regarded almost as a “erra incognita, scarcely worth consideration except as the seat of one affection only—that which was generally known as ‘‘a deafness”—now, at its close, this organ is fully-explored ground, and has been proved well worth the exploration. Otology has been raised from the rank of pseudo-quackery to an honourable position in scientific surgery, and its importance and bearing upon the body as a whole is now fully recognised. THE results of experiments on the ignition of fire-damp and coal-dust by means of electricity were given in a paper by Herr Heise and Dr. Theim, recently read before the Institution of Mining Engineers. The object of the experiments was to deter- mine to what extent electrically driven machinery is dangerous in fiery or dusty mines. In brief, the sum of the results obtained show that in general the amount of electrical energy which is capable in certain circumstances of igniting fire-damp need only be extremely small. This amount cannot be definitely fixed, however, as it depends not only on the quantity of energy but on the mode of its application and other attendant circumstances. It is only in the case of a current the conditions of which are exactly known that quantitative statements can be made as to the limits of safety for certain classes of transformation of energy. In any case, all visible sparks may be looked upon as dangerous. Experiment alone can decide whether certain classes of sparks AuvcustT 10, 1899] may be devoid of danger. Explosions of coal-dust alone appear to be impossible of production by electricity, unless indeed specially dangerous classes of coal-dust behave differently from those tried. A copy of a paper by Dr. J. S. Haldane, F.R.S., and Mr. F. G. Meachem, containing observations on the relation of underground temperature and spontaneous fires in the coal to oxidation and to the causes which favour it, has been received from the Institution of Mining Engineers. The conclusions to which the results of the investigations have led the authors are as follows: (1) A very large amount of heat, sufficient often (if not otherwise absorbed) to heat the air-current to boiling point, is always being formed in a mine, and this heat is almost entirely produced by oxidation of material in the mine. (2) The heat formed greatly exceeds in amount, as a rule, the heat withdrawn by the air-current, so that the temper- ature of the mine, or of some parts of it, is above that of the strata. (3) The disappearance of oxygen and liberation of heat in the mine are probably due, largely at least, to oxidation of iron pyrites ; and the liberation of carbonic acid in the mine is probably due to the action on carbonates of the sulphuric acid thus formed. (4) Coal, when exposed to air, absorbs oxygen, and may also give off carbonic acid and fire-damp, and a very small amount of carbonic oxide. (5) The rate of absorption of oxygen by coal varies directly with the proportion of oxygen present in the air; and as the temperature of the coal increases in arithmetical progression the rate of oxygen-absorption in- creases in geometrical progression, the ratio of increase (for the coal experimented upon) being about 1/10 for every 4° Fahr. of increase in temperature. THE engineering papers publish particulars of the series of trials made at Liverpool last week of self-propelled vehicles suitable for heavy traffic. The chief object of the trials was to encourage the development of types of heavy motor wagons suitable for trade and agricultural requirements. The trial runs were made from Liverpool, over distances of from thirty to forty miles, on two successive days. All vehicles were required to traverse the prescribed routes without alternative, and to per- form other manceuvres. The distance between any two of the depots provided for the supply of water did not exceed twelve miles. Steam was used as the motive power in the six vehicles entered for competition this year. Oil was used for fuel in three, coal in two, and coke in one. Electricity and oil motors were unrepresented in the competition. The following awards were made by the judges:—In Class B, for vehicles having a minimum load, 2 tons; maximum tare, 2 tons ; minimum level platform area, 50 square feet, a gold medal to the Steam Carriage and Wagon Company (Thorneycroft), Chiswick, and_ silver medals to Bayley’s, Limited, and the Lancashire Steam Motor Company. In Class D, for vehicles with a minimum load of 64 tons ; maximum tare, 4 tons ; minimum level platform area, 110 square feet, the gold medal was awarded to the Steam Carriage and Wagon Company (Thorneycroft). A CoMMITTEE of the British Association was appvinted in 1896 to take any possible measures to secure uniformity in the pages of scientific transactions and serials, so that parts of various publications can be bound together by those interested in particular subjects. The Committee has already issued one report, and has since been taking steps to bring before the various societies which publish Proceedings and Transactions the advisability of bringing their publications into harmony, so far as size of paper is concerned, with the standard sizes which already prevail in a great majority of scientific journals and almost uniformly in the case of those longest established. As the result of the inquiries the Committee has issued a circular NO. 1554, VOL. 60] NATURE 351 giving the dimensions of the standard octavo and standard quarto size recommended for scientific publications. It is strongly recommended that every article should always begin at the top of a right-hand page, even if that involves a blank left-hand page, so that a paper can be extracted from a journal without mutilating one or two others. THE Deutsche Seewarte has published a discussion of the storms experienced in the North Atlantic Ocean during the last week of January and the first weeks of February last. It will be remembered that it was during this exceptionally stormy period that the liners Pavonza and Bulgaria suffered so severely. The investigation shows that very unusual weather extended from the Rocky Mountains across the whole of the North Atlantic to the Ural Mountains, and that the storms over the British Islands and North-west Europe were accompanied by unusually high temperature, and blizzards occurred over the United States. The principal features of the storms were their great intensity and almost uninterrupted succession, and the period was characterised by the relatively southerly position of the zone in which the principal barometric minima occurred, and pursued the easterly direction in which they usually travel. The work has been prepared by Dr. E. Herrmann, and is illustrated by several charts. We understand that the Meteorological Council are also preparing for publication a more elaborate discussion of this stormy period. THE Central Physical Observatory and the Geographical Society of St. Petersburg sent up an unmanned balloon on March 24, with duly verified meteorograph. The balloon started about 8 a.m. ; in the course of an hour it had attained a height of 10 kilometres and was travelling at the rate of 75 kilometres an hour, according to photogrammetric observations made at Pavlovsk Observatory. The balloon was not found until May 9, 700 kilometres to the east of St. Petersburg. The instruments were in good condition, but the trace had suffered from exposure to the weather. The legible portion showed that at starting the temperature was —3°'S F. ; at 3900 metres it had fallen to —29°°6, at 4925 metres to —41°°3, and at 6559 metres to —60°'1 ; at 6878 metres the temperature was — 62°°9, while at the highest point shown by the curve, 7223 metres, the reading had risen to —61°°4. A REPORT on clock-rates and barometric pressure as illus- trated by the mean-time clock and three chronometers at Mare’s Island Observatory, together with a brief account of the observ- atory, is contributed to the Pud/icatéons of the Astronomical Society of the Pacific, No. 68, by Ensign Everett Hayden, of the U.S. Navy. The paper is illustrated by a diagram of the baro- meter-rate curve of the mean-time clock, and from this and other tables it is inferred that the best chronometers show a remarkably regular change of rate for differences of pressure, running about ‘tos. faster for a decrease of ‘10-inch of mean barometer. It is suggested that the rate curves of such chrono- meters should be drawn for a mean pressure of 30°00 inches, with similar curves to the right and left for each tenth lower and higher pressures, respectively, for, say, five-tenths of an inch, for the practical use of navigators. A LENGTHY paper on the influence of magnetism on the luminescence of gases has been contributed to the Budletin de Ja Classe des Sciences of the Belgian Academy (part 6), by M. A. de Hemptinne. The author has studied the action of mag- netism on tubes without electrodes excited by electric vibrations ; and he examines in succession the influence of the pressure of the gas, the length of the electric wave, the nature of the gas, and the influence of the medium. The paper concludes with theoretical considerations relating to the observed facts. 352 IN AVEOLL: [AucusT 10, 1899 Part 6 of the Bulletin de la Classe des Sciences of the Belgian Royal Academy contains a preliminary report from the Belgian Antarctic Expedition on the soundings of the Bedgica, drawn up by M. Henryk Arctowsky. Between the channels of Tierra del Fuego and the archipelago of Dirck Gherrits a section was taken of the large Antarctic channel which separates the extremities of the Andes from the hypothetical Antarctic continent. More- over, within the Antarctic circle and on the west of Alexander Land a series of soundings were taken while the ship was drift- ing with the pack ice. The principal bathymetric discoveries were (1) a deep flat-bottomed basin between the south side of the Andes and the mountain system forming the framework of the lands visited by the expedition; (2) in places a sharp declivity forming a demarcation to the continental plateau ; (3) the existence of a continental plateau west of Alexander Land, and south of the 71st parallel. : From Dr. A. Goldhammer we have received copies of notes published by him in Wedemann’s Annalen 65 and 67, dealing, one with modern theories of electromagnetic phenomena in iron, nickel and cobalt, and the other with the Zeeman effect. In the former paper the author compares his equations with those obtained by Mr. J. G. Leathem, of Cambridge. IN the Journal de Physique for June, M. Coloman de Szily investigates the effect of torsion on the electric resistance of The substance used in the experiments was an alloy called ‘‘ constantan,’’ whose resistance is but slightly affected by changes of temperature. The general conclusions are: that torsion increases the electric resistance of a wire; that up to the limit of elasticity the increase is roughly proportional to the angle of torsion, but beyond that limit it increases more rapidly ; and that the resistance of a twisted wire decreases slowly with the time. wires. In Cosmos, No. 744, M. A. Acloque discusses the affinities between cadelis-flies and moths. The author considers that even if the distance between the Trichoptera and Lepidoptera is not great, there is at the same time a considerable gap separating them, and that little or no light on the question of a previous connection between the two orders is at present afforded by paleeontological considerations. Dr. FELICE DELL’ ACQuA, writing in the Rendicont: del R. Istituto Lombardo, brings forward considerations, both statistical and hygienic, relative to the consumption of meat food. It would appear that in Milan the average daily consumption of meat amounts to only 1544 grammes per head of population, and this the author considers is insufficient. After pointing out the desirability of paying greater attention to the diet, especially of working people, Dr. dell’ Acqua discusses the beneficial effects of a fair proportion of meat on the general physique. The various ways of increasing the supply of meat are con- sidered. Dr. dell’ Acqua strongly urges the desirability of breed- ing more cattle in Italy, and of not slaughtering immature animals. Of other sources capable of yielding greater supply than at present, the author calls attention to fish, rabbits and birds, and he suggests the acclimatisation of foreign animals and even the use of horse-flesh. It would appear that in Italy con- siderably less animals are slaughtered for food in proportion to the population than in France or Germany, or especially England. UNDER the title ‘‘ The Honey Bee: a Manual of Instruction in Apiculture,’” by Mr, Frank Benton, the U.S. Department of Agriculture published a very useful Azd/etzn three or four years ago. Twenty-one thousand copies of the manual have been dis- tributed ; and the third edition, containing a few additions and NO. 1554, VOL. 60] changes, has now been published. The magnitude of the apiarian industry in the United States may be judged from _ the fact that more than 300,000 persons are engaged in the cul- ture of bees, and the present annual value of apiarian products is estimated at 4,000,000/7. Mr. Benton states, however, that the present existing flora of the United States could support ten times the number of colonies of bees it now supports. An advantage of this branch of agricultural industry is that it does not impoverish the soil in the least, but, on the contrary, results in better seed and fruit crops. For instance, Dr. L. O. Howard points out that recent investigations have shown that certain varieties of peas are nearly or quite sterile unless hees bring pollen from other distinct varieties for their complete cross fertilisation. Mr. Benton’s treatise will continue to be of great assistance to persons engaged in the management of bees for profit. In the Verhandlungen der k. k. geol. Reichsanstalt, Nos. © and 7, 1899, Dr. M. Remes deals with the question of palaeont- ological divisions in the Tithonian limestone of Stramberg. This limestone, as is well known, has yielded a varied and specially interesting assemblage of life-forms, including types of both jurassic and cretaceous character, and is to be looked upon as representing a true passage series. The author gives a brief account of the attempts that have been made to distinguish divisions of horizon or organic facies in the Stramberg Beds, and points out that insufficient care has hitherto been exercised in keeping separate the fossils collected from the various ex- posures in the one neighbourhood. With the results of his own studies as a groundwork, as well as the long experience of his father in the same field of observation, Dr. Reme& is enabled to show the character of the fauna collected from five different ex- posures, and to point out petrographical similarities and differ- ences. He concludes that the Stramberg limestone forms a uniform mass which, while not satisfactorily showing stratifica- tion, permits a division according to facies in its different parts. It is found that a separation of the jurassic fauna with Zere- bratula moravica from the cretaceous fauna with 7. janztor, as proposed by Hébert, cannot be justified ; a mingling of jurassic and cretaceous forms occurs in like manner at all the points examined. The division adopted by Dr. Remek, according to organic facies, is threefold. He distinguishes a cephalopod- facies (in the Kotoué-Schlossberg rock-complex), a coral- and sponge-facies (Gemeindesteinbruch complex), and an echin- oderm-facies (in the red limestone of Nesselsdorf). The passage of these single rock-masses into one another is stated to be gradual. Dr. TH. TcHIsTovircH has made the toxic properties of eel- serum the basis of some important investigations on the mechanism of immunity. These researches emanate from the laboratories of Profs. Metchnikoff and Roux at the Paris Pasteur Institute, and are published in the dzna/es. Amongst other interesting facts brought to light is the discovery that during the process of immunising an animal against the toxic effect of eel-serum, although it may be trained to resist increasing quanti- ties of the toxin, the avéz/oxéc properties of this animal’s blood- serum do not increase; on the contrary, the antitoxin of a greater or less degree of strength elaborated during the early stages of the immunising process steadily declines in antitoxic value as the animal gains in power of resisting the toxin. The presence, therefore, in the blood of an immunised animal of an antitoxin of a greater or less degree of strength cannot be held to furnish any information or standard as to the degree of im- munity acquired by that animal. Immunity, therefore, depends not solely on the production of an antitoxin in the blood, but on some other mechanism which Dr. Tchistovitch considers may in all probability be dependent upon the leucocytes, AvcustT 10, 1899] AN account of an investigation of a fungus which has done serious damage to the cacao industry in Trinidad is given in the Kew Bulletin (Nos. 145-146). Mr. J. H. Hart, Super- intendent of the Royal Botanic Gardens, Trinidad, sent to Kew material for examination, and the report upon it states :— “* Microscopic examination revealed the presence of two distinct fungous parasites, one being the well-known Phytophthora omnivora, De Bary, a species closely allied to Phytophthora infestans, De Bary, the cause of the potato disease ; the other a Nectria, which proves to be new to science, and will be known as Nectria Bainiz, the name suggested by Mr. Hart in com- pliment to Mr. Bain, who first called attention to the disease. The Phytophthora was present on all the pods sent, and may be considered as the cause of the present epidemic in Trinidad. The same, or a closely allied species, appears to be the cause of the cacao-pod disease in Ceylon. The Mectvia appeared on two pods, and this again possesses many points in common with the JVecévéa, which has caused such destruction to cacao trees in Ceylon by attacking the bark of the trunk and branches, as described by Mr. J. B. Carruthers. At present no mention is made of other than the pod-disease in Trinidad, but the fact of a parasitic Nectrta being present necessitates the prompt execution of measures calculated to prevent the parasite from extending its ravages.” Mr. G. Massee describes each of the species, and states the measures which should be taken to combat the disease. REPORTS on experiments on the manuring of oits, hay, and potatoes, and on the feeding of sheep, conducted in 1898 on farms in the centre and south-west of Scotland, are contained in the sixth annual report just issued by the agricultural depart- ment of the Glasgow and West of Scotland Technical College. The director of the experiments is Prof. R. Patrick Wright, and under his guidance a large amount of serviceable information, similar in character to that obtained at the Agricultural Experi- ment Stations in the United States, Canada, and elsewhere, has been made known. By a scheme framed by the Scotch Educa- NATURE tion Department, the Agricultural Department of the College | referred to has been merged into the newly-formed West of | Scotland Agricultural College ; so the present report is the last of its series, though it is hoped that under the new college a | considerable development of the scope and usefulness of the work of agricultural education and research will be rendered possible. Vor. I. No. 12, of the Records of the Botanical Survey of India is occupied by Mr. V. F. Brotherus’ Contributions to the Bryological Flora of Southern India. A number of new species of moss are described. THE first part of the second volume of the British Museum Catalogue of the African Plants collected by Dr. Friedrich Welwitsch, dealing chiefly with the monocotyledons of the collection, by Dr. A. B. Rendle, has been published. Messrs. SWAN SONNENSCHEIN AND Co. have published a second impression of ‘An Introduction to the Study of Zoology ” by Mr. B. Lindsay. The volume is intended for readers beginning the study of zoology, and its chief distinc- tive characteristic is said to rest ‘‘in its attempt to present the system of classification by grades in a form suited to the necessities of elementary and popular teaching.” THE number of the Biologisches Centralblatt for July 15 contains a very useful summary, by Prof. Moebius, of recent ad- vances in our knowledge of the mode of impregnation in Gym- nosperms and other flowering plants, derived from the remarkable observations of Webber, Ikeno, Hirasi, Nawaschin, Guignard, and Lotsy. The paper is illustrated by several figures. NO. 1554, VOL. 60] 353 To the practical engineer Molesworth’s ‘‘ Pocket-book of Useful Formule and Memoranda” is invaluable. The fact that the twenty-fourth edition, revised and enlarged, has just been published, indicates the extent to which the book has met with approbation. An entirely new electrical section has been added, and will increase the usefulness of what has long been a very serviceable manual. Contributions from the Botanical Lasoratory of the University of Philadelphia, Vol. ii. No. 1, is full of interesting papers. Dr. Lucy L. W. Wilson has some observations on the life- history of Cozopholzs americana, a remarkable American para- sitic plant belonging to the Orobanchez. Elizabeth A. Simons gives the results of a series of experiments on the rate of circum- nutation of the growing stem of som2 flowering plants, which she finds to be considerably more rapid than the rate stated by Darwin. Mr. R. E. B. McKenney describes observations on the development of some embryo-sacs, chiefly Scz//a and Hy- acinthus, The present publication affords one among many illustrations of the extent to which scientific research is being carried out by ladiesin the United States. Out of nine papers in this number, five are by women. THE first number of the Yorkshire Ramblers Club Journal is a very creditable production. Original contributions, reviews, illustrations, and reprints of articles which have appeared else- where are included, dealing with various phases of activity of the Club. Noteworthy among the subjects dealt with are the mountains and snow fields of Norway, and the caves and pot- holes of Yorkshire. A large number of the caves in the carboniferous limestone still remain unexplored ; and the Club is busily engaged in this almost inexhaustible field of ‘‘ under- ground mountaineering” and research. The manner in which the work of exploration has been carried on and the results achieved have already conferred distinction upon the Club, no less than on the members who are its pioneers. We shall look to future numbers of the Jowrnal for particulars of new explorations. SEVERAL publications containing the results of meteorolog- ical observations have lately come to hand. From Prof. J. M. Pernter we have received vols. 32, 33-35 of the Jahrbiicher of the K.K. Central-Anstalt fiir Meteorologie und Erdmagnet- ismus, Vienna, containing tabulated results of daily meteor- ological observations made in Austria during 1895, 1896 and 1898.—The Jahrbuch of meteorological observations made during 1897 at the observatory attached to the Aagdeburgésche Zeitung, edited by Herr R. Weidenhagen, has, in addition to the usual tables, a number of curves showing graphically some of the results. —The Ergebnisse of hourly observations made at Bremen in 1898, edited by Prof. Paul Bergholz, have been pub- lished. —Sir Cuthbert E. Peek has issued his annual statement of meteorological observations made at his observatory, Lyme Regis, during 1898. A special tower has been erected for the anemometers, and upon it are placed a Dines’ pressure-tube recording anemometer and a Robinson anemometer, so that the two instruments can now be compared under very favourable conditions. SEVERAL new editions of scientific works have lately been received. The publication, by Mr. Murray, of the third edition of Mr. Edward Whymper’s guide to ‘‘The Valley of Zermatt and the Matterhorn ” and the fourth edition of ‘‘ Chamonix and the Range of Mont Blanc ” -is well-timed. All visitors to Switzerland should provide themselves with one or both of these interesting and serviceable handbooks.—A second edition of Prof, Henry Louis’s “ Handbook of Gold Milling” has been published by Messrs. Macmillan and Co. The book originally appeared in 1893, since which date great advances have been 354 NALORE [AucusT 10, 1899 made in the art of gold extraction. So far as possible, account has been taken of all important processes in bringing the book up to date.—Dr. David Walsh’s volume on “* The Rontgen Rays in Medical Work” (Bailliére, Tindall, and Cox) contains much information of interest to all who desire to know how far Rontgen rays have been utilised in medical and surgical cases. To the physician and surgeon this second edition should be of great service in showing what has been done. Referring to the progress made since the publication of the first edition, Dr. Walsh says: ‘In practical work the times of exposure are shorter, results more certain, and the merits of the statical machine more widely recognised.”—A second edition of ‘‘A Text- book of Applied Mechanics,” by Prof. Andrew Jamieson, has been published by Messrs. Charles Griffin and Co., Ltd. This book has been revised and extended, the chief additions being in the part on hydraulics and hydraulic machines.—The case for cremation as a means of disposing of the dead is forcibly stated by Sir H. Thompson in ‘Modern Cremation” (Smith, Elder, and Co.), the third edition of which, revised and much enlarged, has just been published. The volume brings up to the present date the history of the practice of cremation, and of the work of the Cremation Society of England. THE additions to the Zoological Society’s Gardens during the past week include a Tantalus Monkey (Cercopithecus tantalus) from West Africa, presented by Mr. W. Knight; two Hairy Armadillos (Dasypus villosus), a Geoffroy’s Cat (Felis geoffrozz) from La Plata, presented by Mr. W. Brown ; a Magpie (Pca rustica), British, presented by Mr. S. B, Goldsmith ; a Red- eared Bulbul (Pycnonotus jocosus), a Yellow-bellied Liothrix (Liothrix luteus) from India, presented by Miss Petrocochino ; two Goshawks (Astur palumbarius), European, presented by M. P. A. Pichot ; three Spotted Tinamous (Worthura maculosa) from Buenos Ayres, four Rufous Tinamous (RAynchotus vufescens) from Brazil, presented by Mr. Ernest Gibson ; two Black-eared Marmosets (Hapale penzciilata) from South-east Brazil, two Maholi Galagos (Ga/ago maho/z) from South Africa, a Sooty Phalanger (Z72chosaurus fuliginosus) from Tasmania, a Malabar Squirrel (Scevrws maximus, var. dealbatus) from India, a Long-necked Chelodine (Chelodina longicollis) from South Australia, two Serrated Terrapins (Chrysemys scripta) from North America, deposited ; a Grison (Gad¢ctes vttata) from South America, two Superb Tanagers (Cad/zste fastwosa),a Blue and Black Tanager (Zanagrelia cyanomelaena) from Brazil, a Thick-billed Tanager (Zzphonta lanztrostris) from Central America, purchased; a Common Mynah (Acridotheres tristés) from India, received in exchange. OUR ASTRONOMICAL COLUMN. HoimeEs’ CoMET, 1899 d (1892 III.).—A new ephemeris for this comet is given by Mr. H. J. Zwiers in Astr. Nach. (Bd. 150, No. 3582). It is important that as many observations as possible should be secured, in order to provide the necessary data for a more correct determination of the orbit. Ephemeris for 12h. Greenwich Mean Time. 1899 R.A. Decl. Br. aiyinle S. ee * x2, (vA). Aug. 10 ... 2 43 48°80 .. 34 39 464 II... 44 56°27 ... 34 55 39°6 12... 46 2°64 ... 35 II 29°8 ... O'1940 ... 0'04674 13+. 47 7:80). 35 27 4l0°9 T4040) LOOM eR 504311029 15... 49 14°92 ... 35 58 41°7 16...) 50) 16166)... 36, 14°-19°2 ... O71923)".. (O1047 Sr 17) We) 205 Tesl7ahye 3 OR2O) bat Comer Swirr (1899 a).—Observers still interested in this comet, and possessed of the necessary optical means, will find an extended ephemeris in the Ast. Mach. (Bd. 150, No. 3583) NO. 1554, VOL. 60] situated on the eastern side of Bering Sea. by Herr J. Moller, of Kiel. The positions and relative bright- ness are given up to September 16, but it is only with the largest instruments that the comet can be at all detected. THE New ALGOL VARIABLE.—In Harvard College Observ- atory Circular, No. 44, Prof. E. C. Pickering gives an ephemeris for observations of this recently discovered variable. The fol- lowing are the predicted minima during the nights of the present month :— Heliocentric Minima of B.D. 45°°3062. 1899, August 11, at 11h. 43m. » ” 20, at 15h. 12m. The position of the star is R.A. 20h. 2'4m. | Decl. SAR SS all (1855), and its normal magnitude about 8°6. DousLe STAR CATALOGUE.—Mr. R. G. Aitken has com- municated to the Astr, Nach. (Bd. 150, Nos. 3584-5) his observations of 319 double stars made during the year 1898. The measures were made with the filar micrometer, in con- junction with either the 12-inch or 36-inch refractor, at the Lick Observatory. The star places are all reduced to epoch 1900, and the data given are time of observation, position angle, distance of components, and their individual magnitudes. ELEMENTS OF COMETARY ORBITS.—M. G, Fayet has ex- tended Oppolzer’s ‘‘ Traités des Orbites,” and brought it up to date by giving the approximate elements for the year 1900 of all the comets hitherto observed. The list is divided into three portions, dealing with comets having elliptic, parabolic, and uncertain orbits respectively ; 106 comets are given with elliptic elements, and 104 with parabolic elements, the dates of observ- ation extending from 1702 to the present time. Fifty-one comets of uncertain elements are given, extending from 137 B.C. to 1880. This list of cometary elements will be especially useful in referring to the elements of any new comet, to see if it is really a new member of the solar system or a return of one previously recorded. THE FUR-SEAL HERDS OF THE NORTH PACIFIC. EW commercial industries command a more varied or more widely spread series of interests than does the sealing trade of the North Pacific. In addition to the great biological in- terest attaching to the seal-herds, we have, first of all, a considerable number of Aleuts dwelling on the islands to drive, kill, and skin the seals, and who subsist to a certain extent on seal-flesh. Then there is the revenue drawn by the American and Russian Governments for the right of sealing on their respective islands, as well as the Customs dues levied by the former on the dressed seal-skins when re-imported into their territory. Not to mention the transport of the raw hides, the dressing of the latter and their conversion into commercial seal- skin forms a very important industry in London, which employs a large number of hands. There are, moreover, the vessels and their crews, which have of late years been engaged in pelagic sealing ; a large proportion of which sailed from Canadian ports. Finally, there is the manufacture of the finished seal-skin into garments, and the retail sale of the latter. From all points of view a cordial welcome should, therefore, be extended to the issue by the United States Government of the official Report of the Commissioner in charge of the fur- seal investigations of 1896-97. This Report, which bears the title of ‘‘ The Fur-Seals and Fur-Seal Islands of the North Pacific Ocean,” is in two parts, and comprises the final results of the investigations carried on by the Commissioner and his associates, as well as the recommendations jointly formulated by the American and British members of the International Commission. The fur-seals of the Northern Pacific comprise three distinct herds, which are stated to keep strictly apart from one another, having each their own breeding-places, feeding-grounds, and routes of migration. The most important of the three herds is the one resorting for breeding purposes in summer to the islands of St. Paul and St. George in the Pribyloff group, In winter this herd Auvéust 10, 1899] NATURE 355 passes through the channels of the Aleutian chair into the Pacific, ranging as far south as Southern California, and return- ing to their summer haunts along the American coast. Next in importance is the Komandorski herd, the members of which breed upon Bering and Medui islands in that group, migrating in winter down the eastern coast of Japan, and returning by the same route the following summer. Smallest of all is the Robben Island herd, now restricted to Robben, or Tiuleni Island, in the Sea of Okhotsk, just south of Saghalien, but which formerly also colonised four islands of the Kurile chain. The line of migration of this herd lies through the Sea of Japan, so that it never enters the open Pacific. Whereas the Pribyloff herd, which is the one to which the present Report, so far as published,' mainly refers, is the property of the Government of the United States, the other two belong to Russia. So far as can be ascertained, the Komandorski and Pribyloff herds were unknown to man (except during migration) till the discovery of the former islands by Bering in 1741, and of the latter by Pribyloff in 1786. Hitherto the seals of all three herds have been regarded as constituting a single species, Ofaria (or Callorhinus) ursina, although differences in colour, shape, and the character of the fur have long been known to exist between them. From the complete isolation of the three herds, and the apparent absence of intermediate forms, Dr. Jordan, the American Commissioner, feels justified in regarding them as indicating as many distinct species, the leading characteristics of which are indicated in the Report. The typical zszva is represented by the Komandorski herd, while to the Pribyloff form is assigned the name a/ascana (alascanus if Callorhinus be recognised as a genus) and to the Robben Island seals that of cz¢/ens¢s. To our own thinking it would have been better if these three forms had been regarded as subspecies, and that such a classification at one time occurred to Dr. Jordan, seems to be indicated by the circumstance that the page (45) of the Report on which they are described is headed ‘‘ The Subspecies of Fur-Seal.” The fact that the fur-seals resort every summer in great numbers to the Pribyloffs for breeding purposes is doubtless well known to the great majority of our readers, but as some new facts in regard to their period of residence on the islands and their habits while there are recorded in the Report, a brief sketch of this period of their existence may not be out of place. The old breeding ‘‘ bulls” are the first to put in an appear- ance, their average date of landing being about the first of May. The younger bulls do not land till the arrival of the ‘‘ cows,” when they ‘haul out” and pass round the ‘‘ rookeries” to places in the rear, or fight their way through the territories of the old bulls in possession. The ‘‘ bachelors,” or immature males, begin to arrive about the same time as the old bulls, usually making their appearance according to age; the smaller seals beginning to predominate after July 9. The older bachelors being alone killed in the Pribyloffs, as many as possible are slaughtered before the arrival of their younger brethren, regular driving usually commencing about:June 1. It is about June ro that the adult cows begin to arrive, their appearance and land- ing, like that of the adult bulls, being gradual. Their arrival is not, as has been stated to be the case, an occasion of fighting among the old bulls for their possession. As a rule, a female about to land reconnoitres the shore by swimming backwards and forwards, and then lands on the rocks, where she is im- mediately taken in charge by the nearest bull. If a bull dis- covers her while attempting to land, she endeavours to escape ; but if this is impracticable, she submits and takes her station on shore beside him. When a bull once obtains a cow, his station becomes an objective point for all the others landing in the vicinity, and a ‘‘harem” is thus formed; large ‘‘harems” being thus constituted in the neighbourhood of favourite landing-places. Soon after landing the cows give birth to their “* pups ” (one in number to each cow). In the larger rookeries as many as a hundred cows may go to the formation of a single harem; and so long as they remain quietly resting before and after the birth of their pups, the one bull has no difficulty in keeping them under control. But as soon as the pairing-season sets in (which it does very soon after the birth of the pups) the old bull is unable to manage his harem, and the ‘‘idle bulls” around enter the circle. With the ‘‘ podding” (collection in masses) and scattering of the pups and the influx of fresh cows, the area occupied by the 1 Two other parts of the Report are announced, the second (iy.) of which will deal with the Komandorski and Robben Island herds. NO. 1554, VOL. 60] seals gradually extends, and fresh bulls are taken into the circle, until the utmost limits of expansion are reached. The population of breeding cows gradually increases from the beginning of the season till about the middle of July, from which period it diminishes till the close of the breeding-season, about August 1, the height of the season being about July 15, when the maximum number of breeding cows are on shore. It is not, however, to be assumed that by any means all the cows are then on land—quite the contrary. From about June 10 or 12 onwards fresh cows are constantly arriving at the rookeries, each cow making a sojourn of about ten or twelve days, after which she starts on her first excursion to the feeding-grounds, distant between one and two hundred miles. The height of the season accordingly means merely that the stream of arriving cows is about counterbalanced by the departing one. Throughout the breeding-season a band of sleeping, playing, and swimming seals skirts the sea-front of each rookery, the majority of these being cows, although some are bachelors. This band includes the arriving and departing cows ; the former gradually edging themselves nearer and nearer to the shore, while the latter tend to the seaward fringe. So stealthily is the landing and the departure accomplished, that it is a very difficult matter to observe a cow either in the act of landing or of setting out to sea, One reason of the loitering before land- ing seems to be to allow time for the complete digestion of the food, which always takes place while at sea. As the bachelors likewise make periodical journeys to the feeding-grounds, it is evident that it is only the bulls which fast throughout the breeding-season ; and for the purpose of enduring this, they accumulate a thick layer of blubber previous to landing. On landing from one of her feeding expeditions the cow calls lustily for her pup, on finding which she forthwith proceeds to nurse it, the pup then departing and taking no further notice of its parent till it again requires a meal. As the majority of the cows are at sea, a landing cow is immediately surrounded by hungry, and it may be starving, pups, who are driven away with decidedly savage treatment. The pups are entirely de- pendent upon their own mother’s milk till about November, the Commission scouting the idea that there is any promiscuous feeding of the pups by the cows, or that the former subsist in part on a vegetable diet. Mention remains to be made of the landing of the yearling and two-year-old females, whose brothers come to the islands about the first of July and spend their time on the hauling grounds. The two-year-old females reach the rookeries about August 1, and take up their places either in the old harems, or in fresh ones in front of and behind the regular breeding- grounds. Here they are taken charge of by young bulls, and after a short sojourn return to the water. Although the yearling cows apparently arrive with the two-year-olds, they do not make their appearance on the rookeries much before September, and then spend their time in ranging over the Jatter and play- ing with the pups, which by this time have become strong swimmers. In regard to the breaking up of the breeding-season, the old harem-bulls, who have fasted from the beginning of May, begin to desert the rookeries for the feeding-grounds about July 25, their places being taken by the idle bulls. By some time between August 5 and 10, all the adult bulls have departed ; the breeding-grounds being then occupied by the younger bulls and bachelors, who, however, soon return to the sand beaches. At the first approach of winter, which usually occurs in November, the cows and pups start on their journey southward. The bachelors linger for some time longer, in some years a con- siderable number remaining till the end of December or even well on in January ; while in mild seasons some may be seen all through the winter. As a rule, however, November ends the sojourn of the seals on the Pribyloffs, and, class by class, they set out on their winter migration. Such is, very briefly, the life-history of the fur-seals during their sojourn around and on the Pribyloffs. We now proceed to notice, with equal brevity, the decline which has of recent years taken place in the numbers of the herd, the reasons for such decline, and the remedies suggested for its recovery. Since these islands came under the sway of the United States Government only bachelors of a certain age have been allowed to be killed on shore. From 1869 to 1889 the sealing rights were leased to the Alaska Commercial Company, whose annual quota of skins was limited to 100,000, of which 75,000 were to be taken on St. Paul and the remainder on St. George. On 356 NALORE [AucusT 10, 1899 the expiration of this lease the islands were relet for a period of twelve years to the North American Commercial Company, on more advantageous terms, the quota of skins being fixed for the first year at 60,000, while it has since been under the regulation of the Secretary to the Treasury. Putting aside for subsequent mention the question of pelagic sealing, it may be observed that between the years 1871 and 1875 the number of breeding seals and young on the islands was estimated by Mr. Elliott, in round numbers, at 3,193,000. In spite, however, of the fact that this observer did not recognise that only a portion of the cows were on land at any one time, the Commission concludes that this estimate is far too high, and that 1,400,000 would have been a much closer approximation to the truth. They further state that between 600,000 and 700,000 seems to be a fair estimate of the number of breeding females resorting annually to the islands between the years 1871 and 1885; while at the present time (1896-97) the number is only about one fifth of what it then was. As regards the decline of the Pribyloff herd, the best evidence is afforded by the fact that whereas between the years 1871 and 1885 no difficulty was experienced in obtaining the full number of 100,000 bachelor seals of the proper age before July 20, in 1896 it was only found possible to obtain 30,000 fit for killing even by continuing the drives till July 27; while in the follow- ing year, when driving was carried on as late as August IT, only 20,890 were obtained. It is largely on these data that the above-mentioned estimate of the former number of breeding animals is founded. The life of the female seal being estimated at from ten to fifteen years, thirteen years may be taken as an average, during ten of which she is capable of producing young. On this esti- mate 10 per cent. of the breeding females die of old age each winter, in addition to those which perish from other causes. The stock is replenished by the annual addition of the three-year-old females. Among the young and pups the death-rate from natural causes is very high; about two-thirds thus perishing annually before they attain the age of three years, when the females are fit for breeding and the males for killing. The most important of such natural causes are the presence of a parasitic worm on the sandy breeding-grounds, the trampling to death by the ordinary movements or fights of the adults, starv- ation of the pups from being separated from their mothers at a very early age, destruction by the killer-whale, and drowning ‘during the winter storms. In 1896 the number of females with pups on the islands was about 157,000, and in the following year 130,000. In certain rookeries the number of pups had diminished from about 16,240 in 1896 to about 14,320 in 1897, indicating a decrease of about 12 per cent., the number of harems having likewise diminished by about 10} percent. Although precise figures are not avail- able, the total decrease in the number of breeding females for the same period may be put down at about 15 per cent., and that of the males fit for killing at about 30 per cent. Although the exact number to which it is safe to reduce the breeding bulls in a rookery as compared to the cows has not yet been ascertained, it is quite certain that in the Pribyloff herd (here is no reduction of the former to anything near that limit. Consequently the killing carried on in the islands cannot be held responsible for the serious reduction which has of late years taken place in the numbers of the herd. On the contrary, such thinning out of the bachelors has tended to the actual increase of the breeding herd, owing to the less amount of fighting which takes place when the bulls are reduced in number, and the consequent diminished loss of life among the cows and pups ‘owing to such, fights. On the other hand, there is every reason for believing that the ‘waning of the herd is solely to be attributed to pelagic sealing, in which the number of females taken is very largely in excess of the males, while for each female so killed an unborn pup is also destroyed, and in the case of those which have already bred a second pup is starved miserably to death on land. Since the normal rate of increase of the breeding herd is a little short of 17 percent., while the natural death-rate from old age is not far from ro per cent., it follows (without allowing for other natural causes of death among the adults) that not more than about 6-2/3 per cent. of the females can be destroyed by human agency year by year without involving the ultimate destruction of the herd. This limit has been very largely ex- ceeded as the result of pelagic sealing, in which (in spite of statements to the contrary) it is impossible to distinguish NO. 1554, VOL. 60] females from males until too late; and in consequence of this the Pribyloff herd has been so reduced that neither pelagic nor land sealing yields an adequate profit on the money invested. The Commission, indeed, go so far as to say that from a com- mercial point of view the herd is virtually destroyed. ‘* But this,” they add, ‘‘ has not involved the biological destruction of the herd. Under wise protection it may regain its former numbers.” That such protection (which involves the prohibition of the killing of females, and therefore apparently also of pelagic sealing!) may be extended to the herd while there is yet time, must be the hope of every naturalist. Res INHERITANCE OF LONGEVITY IN MAN. “THE object of this paper? is twofold, namely :— (1) To ascertain whether duration of life is inherited, and (2) To exhibit natural selection at work in man. According to both Wallace and Weismann the duration of life in any organism is determined by natural selection. An organism lives so long as it is advantageous, not to itself, but to its species that it should live. But it would be impossible for natural selection to determine the fit duration of life, as it would be impossible for it to fix any other character, unless that character were inherited. Accordingly a preliminary in- quiry as to whether duration of life is inherited or not seems needful before we consider further the plausibility of Wallace and Weismann’s hypothesis. The present paper shows that directly and collaterally duration of life is certainly inherited in the male line. We believe this to be the first quantitative measure of the inheritance of life’s duration. Further data for the inheritance of this character in the female line, and for the study of the inheritance of ‘‘ brachybioty” or shortlived- ness as distinguished from longevity are now being collected. We point out in the paper and endeavour to illustrate by examples the importance of such quantitative measure of the inheritance of life’s duration for actuarial practice. The second aim of our paper seems to us, perhaps, to have the greater scientific importance. In the presidential address at the Oxford meeting of the British Association we were told that no one had seen natural selection at work. In a criticism then published by one of us, it was sug- gested that every one who had examined a mortality table had seen natural selection at work. Now the meaning of natural selection is absolutely simple. All individuals die, but some, better suited by their constitution and characters to their environment than others, survive longer, and so are able, or better able, to reproduce themselves, and to protect for a longer period their offspring. To assert that natural selection does not exist, is to assert that the whole death-rate is non-selective, or is not a function of the constitution and characters of the individual. Looked at from this standpoint the existence of natural selection really becomes a truism. All that remains when we desire to see it at work is to determine the relative amounts of the selective and non-selective parts of the death- rate for individuals living under the like environment. If, therefore, individuals living under much the same conditions are dealt with, the determination of the selective and non- selective death-rates isa measure of the quantitative amount of natural selection. Now we can answer this problem in two ways. First we may take any organ, and determine whether the death-rate is a function of the size of this organ. This method, adopted by Prof. Weldon, would be the direct and best method, if the results were not apt to be screened by other factors. In the first place we have to hit upon some organ upon which vitality largely and sensibly depends ; and this is not easy, for constitutional power of resisting the attacks of disease may depend upon, not one organ, but on the complex relationships of a system of organs, and in the next place the whole problem is rendered difficult by changes due to growth. Inthe second method we do not attempt to select any organ whatever, but select individuals having any general 1 The writer takes this opportunity of mentioning that, misled by a summary of some of the evidence given before the Paris Commissién, he was inclined in the ‘‘ Royal Natural History” to pronounce pelagic sealing more humane than seal-killing on land. 2 “Data for the Problem of Evolution in Man. II. A First Study of the Inheritance of longevity and the Selective Death-rate in Man.” By Miss Mary Beeton and Karl Pearson, F.R.S., University College, London. Received May 29. (Abstract of a paper read before the Royal Society, June 15.) Aucust 10, 1899] NATURE SOV resemblance in their constitution, or in the whole complex of organs and characters, and correlate their fitness for surviving. Now relations or members of the same family are precisely such individuals. If there were no selective death-rate there would be no correlation between the ages of death of, say, brothers. If there were no non-selective death-rate, we ought to find that the correlation between ages of death of brothers takes the value determined for the coefficient of heredity in brothers, e.g. the “4 of stature, fore-arm, cephalic index, eye colour, &c., Actually we find it to be something sensibly less than “4. Our investigation shows that, in round numbers, about 80 per cent. of the death-rate is selective in the case of mankind. To that extent natural selection is actually at work. Combined with the quantitative measures of heredity already published, or ob- tained if not yet published, we can safely conclude that Darwin’s theory of a progressive change due to natural selection com- bined with heredity applies even to mankind to an extent which can be quantitatively measured. The next stage must be an experimental one. Various types of life ought to be submitted to ordeals of a kind like to those which occur in nature, and the correlation between the powers of resistance to these ordeals existing in members of the same family or brood determined. We shall thus be able to ascertain under a variety of circum- stances the relative proportions of the selective and non-selective death-rates. A careful inspection of the characters of the longer-lived families may possibly enable the trained biologist to select some organs or characters to which a direct application of Prof. Weldon’s method can be made, and thus enable us to distribute, so to speak, the total selective death-rate previously discovered among its chief factors; but here it must be remem- bered that relationship of organs may be quite as important as absolute size. The present paper is merely a preliminary study of the selective death-rate in man; but one may venture to express a hope that in a comparatively few years, if enough workers can be found for the experimental side of the subject, we shall no longer hear natural selection spoken of as hypo- thetical, but rather its quantitative measure given for various organisms under divers environments. THE CAUSE AND PREVENTION OF MALARIA. HAVE the honour to address you, on completion of my term of special duty for the investigation of malaria, on the subject of the practical results as regards the prevention of the disease which may be expected to arise from my researches ; and I trust that this letter may be submitted to Government if the Director General thinks fit. It has been shown in my reports to you that the parasites of malaria pass a stage of their existence in certain species of mosquitoes, by the bites of which they are inoculated into the blood of healthy men and birds. These observations have solved the problem—previously thought insolvable—of the mode of life of these parasites in external nature. My results have been accepted by Dr. Laveran, the discoverer of the parasites of malaria; by Dr. Manson, who elaborated the mosquito theory,of malaria ; by Dr. Nuttall, of the Hygienic Institute of Berlin, who has made a special study of the relations between insects and disease; and, I understand, by M. Metchnikoff, Director of the Laboratory of the Pasteur Instijute in Paris. Lately, moreover, Dr. C. W. Daniels, of the Malaria Commission, who has been sent to study with me in Calcutta, has confirmed my observations in a special report to the Royal Society; while, lastly, Prof. Grassi and Drs. Bignami and Bastianelli, of Rome, have been able, after receiving specimens and copies of my reports from me, to repeat my experiments in detail, and to follow two of the parasites of human malaria through all their stages in a species of mosquito called the Anopheles claviger. It may, therefore, be finally accepted as a fact that malaria is communicated by the bites of some species of mosquito ; and, to judge from the general laws governing the development of parasitic animals, such as the parasites of malaria, this is very probably the only way in which infection is acquired, in which opinion several distinguished men of science concur with me. In considering this statement it is necessary to remember that it does not refer to the mere recurrences of fever to which 1 Report from Major Ronald Ross to the Secretary to the Director General, Indian Medical Service, Simla. Dated Calcutta, February 16. NO. 1554, VOL. 60] people previously infected are often subject as the result of chill, fatigue, and so on. When I say that malaria is com- municated by the bites of mosquitoes, I allude only to the original infection. It is also necessary to guard against assertions to the effect that malaria is prevalent where mosquitoes and gnats do not exist. In my experience, when the facts come to be inquired into, such assertions are found to be untrue. Scientific research has now yielded so absolute a proof of the mosquito theory of malaria that hearsay evidence opposed to it can no longer carry any weight. Hence it follows that, in order to eliminate malaria wholly or partly from a given locality, it is necessary only to exterminate the various species of insect which carry the infection. This will certainly remove the malaria to a large extent, and will almost certainly remove it altogether. It remains only to consider whether such a measure is practicable. Theoretically the extermination of mosquitoes is a very simple matter. These insects are always hatched from aquatic larvee or grubs which can live only in small stagnant collections of water, such as pots and tubs of water, garden cisterns, wells, ditches and drains, small ponds, half-dried watercourses, and temporary pools of rain-water. So far as I have yet observed the larvee are seldom to be found in larger bodies of water, such as tanks, rice-fields, streams and rivers and lakes, because in such places they are devoured by minnows and other small fish. Nor have I ever seen any evidence in favour of the popular view that they breed in damp grass, dead leaves, and so on. Hence, in order to get rid of these insects from a locality, it will suffice to empty out or drain away, or treat with certain chemicals, the small collections of water in which their larvae must pass their existence. But the practicability of this will depend on circumstances— especially, I think, on the species of mosquito with which we wish to deal. In my experience, different species select different habitations for tleir larve. Thus the common “*brindled mosquitoes” breed almost entirely in pots and tubs of water ; the common “‘ grey mosquitoes” only in cisterns, ditches and drains; while the rarer ‘‘spotted-winged mosquitoes” seem to choose only shallow rain-water puddles and ponds too large to dry up under a week or more, and too small or too foul and stagnant for minnows. Hence the larvz of the first two varieties are found in large numbers round almost all human dwellings in India ; and, because their breeding grounds—namely, vessels of water, drains and wells—are so numerous and are so frequently contained in private tenements, it will be almost impossible to exterminate them on a large scale. On the other hand, spotted-winged mosquitoes are generally much more rare than the other two varieties. They do not appear to breed in wells, cisterns and vessels of water, and therefore have no special connection with human habitations. In fact it is usually a matter of some difficulty to obtain their larvee. Small pools of any permanence—such as they require —are not common in most parts of India, except during the rains, and then pools of this kind are generally full of minnows which make short work of any mosquito larve they may find. In other words, the breeding grounds of the spotted-winged: varieties seem to be so isolated and small that I think it may be possible to exterminate this species under certain circumstances. The importance of these observations will be apparent when I add that hitherto the parasites of human malaria have been found only in spotted-winged mosquitoes—namely, in two species of them in India and in one species in Italy. As a result of very numerous experiments I think that the common brindled and grey mosquitoes are quite innocuous as regards human malaria—a fortunate circumstance for the human race in the tropics. And Prof. Grassi seems to have come to the same conclusion as the result of his inquiries in Italy. But I wish to be understood as writing with all due caution on these points. Up to the present our knowledge, both as regards the habits of the various species of mosquito and as regards the capacity of each for carrying malaria, is not complete. All I can now say is that if my anticipations be realised—if it be found that the malaria-bearing species of mosquito multiply only in small isolated collections of water which can easily be dissipated—we shall possess a simple mode of eliminating malaria from certain localities. I limit this statement to certain localities only, because it is obyious that where the breeding pools are very numerous, 358 NALORE [AucusT 10, 1899 as in water-logged country, or where the inhabitants are not sufficiently advanced to take the necessary precautions, we can scarcely expect the recent observations to be of much use—at least for some years to come. And this limitation must, I fear, exclude most of the rural areas in India. Where, however, the breeding pools are not very numerous, and where there is anything approaching a competent sanitary establishment, we may, I think, hope to reap the benefit of these discoveries. And this should apply to the most crowded areas, such as those of cities, towns and cantonments, and also to tea, coffee,and indigo estates, and perhaps to military camps. For instance, malaria causes an enormous amount of sickness among the poor in most Indian cities. Here the common species of mosquitoes breed in the precincts of almost all the houses, and can therefore scarcely be exterminated ; but pools suitable for the spotted-winged varieties are comparatively scarce, being found only on vacant areas, ill-kept gardens, or beside roads in very exceptional positions where they can neither dry up quickly nor contain fish. Thus a single small puddle may supply the dangerous mosquitoes to several square miles containing a crowded population : if this be detected and drained off—which will generally cost only a very few rupees— we may expect malaria to vanish from that particular area. The same considerations will apply to military cantonments and estates under cultivation. In many such malaria causes the bulk of the sickness, and may often, I think, originate from two or three small puddles of a few square yards in size. Thus ina malarious part of the cantonment of Secunderabad, I found the larvee of spotted-winged mosquitoes only after a long search in a single little pool which could be filled up with a few cart-loads of town rubbish. In making these suggestions I do not wish to excite hopes which may ultimately prove to have been unfounded. We do not yet know all the dangerous species of mosquito, nor do we even possess an exhaustive knowledge of the haunts and habits of any one variety. I wish merely to indicate what, so faras I can see at present, may become a very simple means of erad- icating malaria. One thing may be said for certain. Where previously we have been unable to point out the exact origin of the malaria in a locality, and have thought that it rises from the soil generally, we may now hope for much more precise knowledge regarding its source; and it will be contrary to experience if human ingenuity does not finally succeed in turning such information to practical account. More than this, if the distinguishing characteristics of the malaria-bearing mosquitoes are sufficiently marked (if, for instance, they all have spotted wings), people forced to live or travel in malarious districts will ultimately come to recognise them and to take precautions against being bitten by them, Before practical results can be reasonably looked for, however, we must find precisely— (a) What species of Indian mosquitoes do and do not carry human malaria. (6) What are the habits of the dangerous varieties. I hope, therefore, that I may be permitted to urge the desirability of carrying out this research. It will no longer present any scientific difficulties, as only the methods already successfully adopted will be required. The results obtained will be quite unequivocal and definite. But the inquiry should be exhaustive. It will not suffice to distinguish merely one or two malaria-bearing species of mosquito in one or two localities ; we should learn to know all of them in all parts of the country. The investigation will be abbreviated if the dangerous species be found to belong only to one class of mosquito, as I think is likely ; and the researches which are now being energetically entered upon in Germany, Italy, America and Africa will assist any which may be undertaken in India, though there is reason for thinking that the malaria-bearing species differ in various countries, As each species is detected it will be possible to attempt measures at once for its extermination in given localities as an experiment. I regret that, owing to my work connected with £a/a-azar, I have not been able to advance this branch of knowledge as much during my term of special duty as I had hoped to do; but I think that the solution of the malaria problem which has been obtained during this period will ultimately yield results of practical importance. NO. 1554, VOL. 6c! UNIVERSITY AND EDUCATIONAL INTELLIGENCE. THE Zimes reports that the University of Berlin celebrated on Thursday last the ninetieth anniversary of its foundation by Frederick William III. The oration was delivered by the re- tiring rector, Dr. Waldeyer, professor of anatomy, who took for his text the question, ‘* Does the University of Berlin fulfil the mission entrusted to it by its founder?” As a contribution to the discussion of this question, he gave a learned and interesting account of the history of anatomical teaching in Berlin. Dr. Waldeyer is succeeded as rector by Prof. Fuchs, the dis- tinguished mathematician. THE Research Fellowships founded by the Salters’ Com- pany and the Leathersellers’ Company for the encouragement of higher research in chemistry in its relation to manufactures, tenable at the City and Guilds Central Technical College, being now vacant, the Executive Committee of the City and Guilds of London Institute will, before the commencement of next session, consider applications and elect candidates. The grant made by each of the companies to the Institute for this pur- pose is 150/. a year. Copies of the schemes under which the Fellowships will be awarded may be had on application to the Honorary Secretary of the Institute, Gresham College, Basing- hall Street, E.C. A copy of the twenty-third annual ‘‘ Catalogue” of the Agricultural and Mechanical College of Texas has been received. All the departments of the College appear to be well equipped, and the buildings and grounds are of a very extensive character. The course of work at the College is designed to enable young men ‘‘ to obtain that education and training which will fit them to take a leading part in the material development of the State ; to become scientific farmers and horticulturists, familiar with the properties and needs of soils, the laws of plant growth, the principles of breeding, and, in general, with rational methods based on the revelations of modern science; to become mechanical engineers, draughtsmen, chemists, civil engineeers, competent to fill responsible positions in these callings—men fitted not only to meet demands made upon them, but to create such demand by pointing the way to progress and development.” THE Royal Naval Engineering College at Keyham was visited by members of the Institution of Mechanical Engineers during the recent meeting at Plymouth, and the excellent opportunities afforded for the efficient training of the engineer students, who are being instructed both theoretically and practicaliy to enable them to become engineer officers in the Royal Navy, were seen. For the last eleven years Keyham has been the only Admiralty training ground for these officers. An entry is made once each year, during the first or second week in July, following a competitive examination held by the Civil Service Commissioners in the previous April. The period of training is five years. Throughout this time they undergo an educational course at the Royal Naval Engineering College under Prof. A. M. Worthington, F.R.S., whilst their practical training is obtained in the dockyard at Keyham, and the work they perform is as far as possible real. In a paper read before the Institution of Mechanical Engineers, Mr. R. Mayston pointed out that the facilities afforded at Keyham for the acquirement of a thoroughly practical training place the Royal Naval Engineering College in the foremost rank as an institu- tion for obtaining a sound knowledge of mechanical engineering. The fact that as soon as possible after entry the student is employed on useful work, the various courses of instruction which are arranged to render the knowledge of marine engineer- ing obtained as complete and as comprehensive as possible, the facilities afforded for acquaintance with running machinery, the constant contact throughout the training with experienced workmen, the frequent opportunities afforded for obtaining information from the officers who have charge of the training, all go to indicate that nothing is spared to make the training of the engineer student as complete as possible. It may, indeed, be accurately said that Keyham College furnishes an example of what technical education should mean, namely, a wise combination of theoretical and practical work. HER Majesty's Commissioners for the Exhibition of 1851 have made the following appointments to Science Research Scholarships for the year 1899, on the recommendation of the authorities of the respective Universities and Colleges. The scholarships are of the value of 1I50/. a year, and are ordinarily tenable for two years (subject to a satisfactory —— se ee he AvuGusT 10, 1899] report at the end of the first year) in any University at home or abroad, or in some other institution approved of by the Commissioners. The scholars are to devote themselves exclusively to study and research in some branch of science, the extension of which is important to the industries of the country. A limited number of the scholarships are renewed for a third year where it appears that the renewal is likely to result in work of scientific importance. Nominating institution Scholar 1 | University of Glasgow | Robert John Tainsh Bell 2 | University of St. Andrews __ James C. Irvine 3 | Mason University College, Birm- | Henry Leonard Heathcote ingham % : 4 | University College, Bristol Winifred Esther Walker 5 | Yorkshire College, Leeds | Frederick William Skirrow 6 | University College, Liverpool | Charles Glover Barkla 7 | University College, London | Harriette Chick 8 | University College, London Henry James Tomlinson 9 | Owens College, Manchester. Frank Austin Lidbury 10 | Durham College of Science, | William Campbell Newcastle-upon-Tyne _ 11 | University College, Nottingham | Louis Lownds 12 | University College of Wales, | James Travis Jenkins Aberystwyth 13 | University College of North | Robert Duncombe Abell Wales, Bangor : 14 | Queen's College, Belfast William Caldwell 15 | McGill University William Brown McLean 16 | University of Melbourne Bertram D. Steele The following scholarships granted in 1898 have been con- tinued for a second year on receipt of a satisfactory report of work done during the first year :— Nominating institution Scholar | Place of study 1 University of Glasgow | James Frank | Owens College ; to proceed Bottomley | to University College, London 2 University of Aber- | Alexander Find- | University of Leipzig deen 4 lay ; | 3. Mason College, Birm- | A. H. Reginald | Botanical Institute, Leip- ingham Buller | zig $ to proceed to Uni- | _versity of Munich 4 Yorkshire College, | Harry Thornton | University of Leipzig Leeds Calvert | 5 University College, | Ernest Brown Central Technical College, Liverpool | South Kensington 6 Owens College, Man- | James Henry | Owens College (permitted chester Smith | under spectal circum- | stances) 7 Durham College of | Arthur William | University College, Lon- Science, Newcastle- Ashton don upon-Tyne 8 University College, | Austin Henry | Cavendish Laboratory, | _ Nottingham Peake J Cambridge 9 Royal College of | Robert L. Wills | Cavendish Laboratory, Science for Ireland Cambridge to Queen's College, Gal- | Hugh Ryan University of Berlin way 1x University of Toronto | William Gabb | University of Leipzig Smeaton 12 Dalhousie University, | Ebenezer Henry | Harvard University Halifax, Nova | Archibald Scotia The following scholarships granted in 1897 have been ex- ceptionally renewed for a third year :— Nominating institution Scholar Place of study, ai ap | 1 | University of Glasgow | James Muir Engineering Laboratory, Cambridge 2 | University of St. An- | Harry McDonald} Gatty Marine Laboratory, drews. Kyle | St. Andrews, Labor- | atoire Arago, Banyuls- sur-mer ; Konigliche Biologische Anstalt, Heligoland 3 | University College, | Charles Henry | Owens College, Man- Bristol Graham Sprank- chester ling 4 | Yorkshire College, | Harold Albert | Cavendish Laboratory, Leeds Wilson Cambridge 5 | University College of | Maria Dawson Botanical Laboratory, South Wales and Cambridge Monmouthshire 6 | University of Mel- | Walter Rosenhain| Engineering Laboratory, bourn Cambridge NO. 1554, VOL. 60] NATURE T 359 IN connection with the article on the duties of provincial professors, which recently appeared in these columns, it is worthy of note that, according to the Hochschul-Nachrichten, 22 per cent. of the professors in the Gerrnan universities are engaged in lecturing or laboratory supervision two to six hours a week, and 51 per cent. from seven to twelve hours. Of the associate professors 60 percent. are engaged from two to six hours per week, and of the privatdocents 82 per cent. Only 4 per cent. of all privatdocents are engaged in lecturing or - laboratory supervision more than twelve hours a week. As Sczence remarks, the leisure of the German associate professors and docents explains in large measure the amount of research work accomplished in German universities. SCIENTIFIC SERIAL. American Journal of Mathematics, vol. xxi, No. 3, July. —This number opens with a long memoir (64 pp.) by Dr. L. E. Dickson, entitled ‘*‘ Determination of the Structure of all Linear Homogeneous Groups ina Galois Field which are defined by a Quadratic Invariant.” This is an attempt at a complete determination of this important type of groups. Dr. Dickson’s work is familiar to the students of ‘‘ groups” in this country by his papers in the Quarterly Journal (on the first hypoabelian group generalised, 1898), in the American Bulletin (the structure of the hypoabelian groups, July 1898, also of the Bud/etzn for February and May 1898), and in the Proc. of the Lond. Math. Soc. (the structure of certain linear groups with quadratic invariants, vol. xxx. pp. 70-98). Two new systems of simple groups are obtained in the present memoir, and thereby some results in the earlier papers are correlated and completed. (References are freely given to results obtained by other workers in this field.)—Upon the ruled surfaces generated by the plane movements whose cen- trodes are congruent conics tangent at homologous points, by Dr. E. M. Blake. The movements considered are thus defined, Upon a plane e@’ containing a conic C’ moves a_ coincident plane a, containing a conic C congruent to C’, in such a manner that C and C’ are always tangent at homologous points, z.e. C and C’ are the centrodes of the movement. The locus of a point rigidly attached to a is a curve of the fourth order when C and C’ are central conics, and of the third order when they are parabolas. The locus is in a plane parallel to a’, and the same distance from it that the generating point is from a. The locus of a straight line carried by a and making an angle with it, is a quartic scroll when the centrodes are central conics, and a cubic scroll when they are parabolas. The object of the paper is to describe the forms of these scrolls, and the character and situation of their nodal lines and pinch-points. The results are to be regarded (1) as furnishing a method of mechanically generating certain cubic and quartic scrolls, and (2) as exhibiting the totality of line-loci of the movements considered. These results are believed, by the author, to be new.—The remaining two papers are by J. C. Glashan, and their nature is indicated by their titles, viz. ** Quinquisection of the Cyclotomic Equation” (read, in abstract, at the British Association meeting of August 29, 1897, ¢f Prof. Cayley’s paper on the subject in vol. xii. of the Z. Math, Soc. Proc.), and on the » fold section of the cyclotomic equation in the case of 7 prime. (Useful references are given to pre- vious memoirs on the subject.)—Accompanying this number is an index to volumes xi.-xx.—The editorial staff is announced to consist of Prof. Newcomb, with the co-operation of A. Cohen, Frank Morley, Charlotte A. Scott, and other mathe- maticians.—This is strong enough for any work that may be placed before it. SOCIETIES AND ACADEMIES. LONDON. Royal Society, June 15.—‘‘On the Waters of the Salt Lake of Urmi.” By R. T. Giinther, M.A., and J. J. Manley, Daubeny Curator, Magdalen College. Communicated by Sir John Murray, F.R.S. This paper contains an account of a physical and chemical investigation of the waters of the great salt lake of Urmi in Azerbaijan, North-west Persia. Samples of the water were 360 NATURE [AucusT 10, 1899 collected by Mr. R. T. Giinther during his expedition to the lake last summer, and were examined by Mr. J. J. Manley in the laboratory of Magdalen College, Oxford. The specific gravity of one of the samples of the water at 15° C. was about I°11338; its boiling point under normal conditions in a platinum bottle was 103'84° C., as determined by a form of platinum resistance thermometer. The refractive index () was found to be 1°36110 by a method which the authors con- sider to be applicable to ordinary sea waters, and to be capable of yielding an indication of the physical nature of the water which is both more accurate and more readily obtainable than the ordinary specific gravity. The chemical examination was, with a slight modification, similar to that employed by Dittmar in his work on the composition of the ocean water collected by the Challenger. The hypothetical proximate composition of 100 parts of the total salts was calculated with the following results :— Sodium chloride 86°332 Magnesium chloride ... 6661 Magnesium sulphate ... 4°211 Calcium sulphate 0988 Potassium sulphate 1°741 99°933 _ Atrace of barium was detected ly the spectroscope. No iodine or bromine could be discovered. It is to be hoped that the constitution of the lake water will ‘be determined again at intervals of a few years, in order to -show whether or not the salinity is undergoing any change, and >if so, in which direction. Paris. Academy of Sciences, July 31.—M. van Tieghem in the -chair,—The Perpetual Secretary announced to the Academy the loss it had sustained by the death of M. Rieggenbach, corre- ‘spondent in the Section of Mechanics. —Thermogenesis and use of energy by man in raising and lowering his own weight, by M. A. Chauveau. The positive work done by the animal motor is shown by experiment to take from the animal heat an amount “quantitatively equal to the mechanical work produced. When the subject does negative work in the calorimeter, the heat pro- duced is much greater than should arise from the normal physio- logical work of the organism.—On the law of pressures in gun-muzzles. by M. E. Vallier. The author applies the formula (previously given by him to the discussion of some experiments ‘by M. Zaboudski, and introduces certain simplifications into his - original expression.—Hypodermic impregnation in the Haemen- taria castata of Miiller (Placobdella catenigera of R. Blanchard), ‘by M. A. Kowalevsky.—On the annular nebula in Lyra, from observations made at the Observatory of Toulouse, by MM. Bourget, Montangerand, and Baillaud. The observations show ‘unmistakably that very sensible changes of brightness have taken \place in this nebula during the last twenty years. — Observations of B-Lyre, made at the Observatory of Lyons, by M. M. Luizet.—On the variable star (D.M. +12°°3557) of the Algol type, by M. Luizet.—On the methods of M. Loewy for the - determination of latitudes, by MM. W. Ebert and J. Perchot.— The variations of the apparent horizon, by M. F. A. Forel. “The possible error in the measurement of the position of the true horizon deduced from observation of the apparent ‘horizon, is greater when the air is calm than when it is in motion, and greater than when the air is warmer than the water than the reverse ; hence the observations are best taken in the morning.—On the equations of Pfaff, by M. 1a eO} Lovett.—On certain differential equations, by M. Henri Dulac.—On the changes of state of iron and steel, by M. H. Le Chatelier.—On the electric deformations of solid isotropic dielectrics, by M. Paul Sacerdote.—On the — spectra of oscillating discharges, by M. G. A. Hemsalech.— With the oscillating discharges, a particular value for the self- induction of the circuit can be made to give a spectrum almost totally free from air lines, and showing very clearly the characteristic rays of the metals forming the electrodes. —On the isomeric states of chromium acetate: biacid abnormal violet acetate and a green abnormal monoacetate, by M. A. Recoura.—Action of magnesium upon saline solu- tions, by M. Georges Lemoine. Concentrated’ solutions of magnesium chloride rapidly disengage hydrogen when treated with ‘magnesium powder, magnesia being simultaneously NO. 1554, VOL. 60] formed.—On the dissociation of the hexammoniacal cadmium chloride, by MM. W. R. Lang and A. Rigaut.—On the disso- ciation of mercurdiammonium iodide, by M. Maurice Frangois. The compound of mercuric iodide and ammonia behaves simi- larly to the ammoniacal silver chlorides, the dissociation pressures showing that an intermediate compound 3Hgl,.4NH, exists. — Action of sodammonium and potassammonium upon selenium, by M. C. Hugot.—On some acetonylacetonates, by MM. G. Urbain and A. Debierne. In the present paper details are given of the iron, manganese, cobalt, chromium, and alumi- nium compounds.—Action of mineral substances and organic acids upon the variations of resistance and modifications of the system, by MM. Charrin, Guillemonat, and Levaditi —Immunity and specificity. Remarks on the preceding note, by M. Ch. Bouchard.—On the gluten and nitrogenous material of flour, by M. Balland. As flour grows older, the gluten appears to under- goa change, as it loses its coagulating properties, and is carried away in increasing quantity by washing with water. —Hstimation of carbon dioxide at the summit of Mt. Blanc, by M. Maurice de Thierry. Details of estimations of ozone and carbonic acids carried out at Chamonix and Grand Mulets in August and September 1898. CONTENTS. Floras from the Royal Gardens, Kew . Se eke Statistical Methods Applied to Biology. By Gai YY. :. "ese eal. ook LS Re Text-Books of Physics. By Prof. Arthur Schuster, FOROS: & :5 0c tc) Reet neaisere 70. |! 3 1e) 2o- ee) Our Book Shelf :— Moxly : ‘‘The Tides Simply Explained : with Practical Hints to Mariners.’—H. H.T. ....... .- 340 Roosa: ‘‘Defective Eyesight” ..... 341 Jackson: ‘‘ The Lancashire Sea Fisheries ”’ me, 1 Gia “‘ A Country Schoolmaster, James Shaw, of Tynron, Dumfriesshirezeweemeeweeeee e's 22! <2 +: ve) Weegee Letter to the Editor :— Apparent Dark Lightning Flashes.—Lord Kelvin, FiR:S... | cee esas 3. so Cen ae Meeting of the British Medical Association at Portsmouth. By Dr. F. W. Tunnicliffe. ... . 341 The Relation of Motion in Animals and Plants to the Electrical Phenomena associated with it. (ilustrated.) By Sir J. Burdon-Sanderson, Bart., EiR.S:) i. Rep US 7) >. =) eee Mathematics of the Spinning-Top. II. (With Diagram.) By Prof. A. G. Greenhill, F.R.S. 346 Notes... . . = Gyieweereneaer 349 Our Astronomical Column :— Holmes’ Comet, 1899 d@ (1892 III.). . ..... - 354 Gomet/Swift (1890}q) meee! cl. |: «ema The New Algol Variable .... - 354 Double Star Catalogue ...++..... 354 Elements of Cometary Orbits. . . . 354 The Fur-Seal Herds of the North Pacific. By R. L. 354 Inheritance of Longevity in Man. By Mary Beeton and Prof. Karl Pearson, F.R.S. _ OS ESE ae 356 The Cause and Prevention of Malaria. By Major Ronald Ross 74] yeeee - - - } =e OME UT University and Educational Intelligence . . . . . 355 Scientific Serial .... Mie ys sie «) 5s so) Societies and Academies'. 2... +. . 6 es © «© 359 NATURE 361 THURSDAY, AUGUST 17, 1899. ENZYMES. The Soluble Ferments and Fermentation. By J. Reynolds Green, Sc.D., F.R.S. Pp. xiv+480. (Cam- bridge University Press, 1899.) vo igiaeae no subject in the whole of the vast domain of biology exceeds this in interest, and certainly none transcends it in the importance of its bearings on the doings of the human race. The bread and cheese we eat, the beer and wine we drink, are en- tirely dependent on these ferments for their preparation ; and the same is true of the processes of digestion which render their products assimilable into the plant or animal economy. Then, have not Pasteur and men who have fol- lowed him made clear that the principle of ferment- ation lies at the root of an enormous class of diseases ; aye, and demonstrated the truth of the doctrine by that most cogent of all arguments—experimental production of the disease from the use of the agents, and cure or prevention of it by the employment of the antidotes and therapeutic measures suggested by the scientific inquiry ? The making of jams, the tinning of preserved meats and fruits, the curing of hides and tanning of leather, and a hundred other branches of industry owe their suc- cessful pursuit to the intelligent application of the teachings of science ; so clearly is this being recognised now, that it is becoming customary to speak of “ fer- mentation industries” as a class. For it must no longer be supposed that brewing is the only fermentation industry ; modern discovery in connection with dyeing, the curing of tobacco, the retting of flax, and many departments of agriculture show the necessity of ex- tending the idea. Dr. Green’s aim has been to collect all that is known of the study of those remarkable and curious bodies (Enzymes) which can be extracted from the protoplasm of living cells, can be precipitated mechanically from the solutions, and preserved as dry, impalpable powders, and still retain more or less unim- paired their astonishing powers of again bringing about decompositions of sugar, fats, proteids and other organic substances in solutions just as they could in the cell itself or in the waters outside the cell. : These powers are astonishing, because they are mani- fested so extensively by almost unweighably small quan- tities of the enzyme, and because they are exerted so smoothly and with such apparent ease and economy on bodies which we know to be very stable, and which can be artificially decomposed in similar ways only by the application of very energetic processes and very wastefully. For it would seem that the study of fermentation is now the study of enzymes. Even the one sharply con- trasted case—alcoholic fermentation—which Pasteur’s classical labours appeared to place in a category apart from those of the enzymes, has come into line with the rest since Buchner’s discovery that an enzyme-like body can be extracted from the cells of the yeast-plant, and can split up sugar into alcohol and carbon dioxide out- side the living cell. NO. 1555, VOL. 60] Very few authors have attempted the collection of the huge and ever-increasing mass of information scattered through the various journals devoted to special rese arches on fermentations, and the student had long been de- pendent on the now antiquated books of Schutzenberger and Naegeli for his summary of general views on the sub. ject, until, in 1893, the extremely interesting but meagre brochure of Bourquelot came out to tantalise him with its disappointing sketch of recent progress. Now we can claim, from the hands of an English botanist, a com- prehensive survey, which, whatever its few faults in detail, covers the enormous area admirably, and brings out the salient points and recent discoveries in a very satisfactory manner. Until a few years ago, it was generally accepted that Pasteurs doctrine—fermentation is the result of life without oxygen—formed the corner-stone of the whole subject. The gradual recognition of the important parts played by the “soluble ferments,” or e”zymes, which, though their discovery dates from 1814, 1823, 1831, were not much studied before 1870, led to the further view that two categories of fermentation-processes must be distinguished, and the attempt was made by Naegeli and Sachs to uphold the idea that soluble or “unorganised ” ferments (enzymes) act differently from “organised” or living ferments—e.g. bacteria, yeast-cells, &c. Apart from other discrepancies, the fact that ferment- ations occur universally in higher plants and animals, as well as in lower organisms, rendered this view un- tenable, until the startling discovery by Buchner, in 1897, that a something of the nature of an enzyme can be extracted in water from the yeast-cell, which—outside the yeast-cell and quite independent of it—converts sugar into carbon dioxide and alcohol, may be said to have removed its last prop. Although Lafar, in his remarkably able summary of the ferment-activity of the lower organisms, restricts the definition of fermentation to “transformations of matter . exclusively by the vital action of ferments,” under- standing by the latter word the living cells themselves, it is evident that we are here confronted with an entirely different definition of fermentation. Having abandoned successively the views that it is a phenomenon of life without oxygen, that it is confined to the protoplasmic activity of lower organisms, that there are two different categories of ferments:-—organised and unorganised, we are now threatened once more with the generalisation that fermentation is a purely chemical phenomenon due to the peculiar molecular activity of certain bodies formed, it is true, by protoplasm, but acting independently of it: a generalisation supported by Fischer’s work on the constitution of the sugars, which he regards as so built up that an enzyme can only attack any particular sugar the molecular symmetry of which is related to its own, much as the wards of a lock can be overcome only by a key with a particular pattern. Dr. Green gives us a very exhaustive account of the many various enzymes now known, classifying them under the following heads. (1) Those which transform insoluble carbohydrates, producing soluble sugars—e.g. Diastase in germinating seeds and other plant-organs, which attacks starch ; R 362 NATURE [AucusT 17, 1899 Inulase, which decomposes inulin ; Cyz¢ase, which hydro- lyses cellulose. (2) Those which transform more complex sugars into simpler compounds of the same class—e.g. Jnuvertase, which attacks cane-sugar ; G/ucase, which splits up maltose, and others. (3) Those which break up glucosides into some sugar and an aromatic body—e.g. Emulsin, which decomposes the amygdalin of almonds into sugar and prussic acid ; Myrosin, which breaks up the sinigrin of mustard into a sugar and the pungent substance so well known. (4) Proteolytic enzymes, such as Pepsin and Trypsin, which decompose insoluble and indigestible proteids into soluble and digestible peptones and other bodies, and play so important a part in digestive processes generally. (5) The clotting enzymes which bring about coagul- ations—e.g. Rennet, so important in converting milk into cheese ; Zhrombase, the enzyme concerned in the co- agulation of blood ; Pectase, the chief agent in forming vegetable jellies. ; (6) The ZLzfases, concerned in decomposing oils and fats. (7) The Oxydases, a curious class of enzymes recently shown to be active in carrying oxygen and bringing about the oxidation of certain vegetable juices—e.g. Laccase, concerned in the formation of lacquer varnish. (8) A number of enzymes as yet unclassified—e.g. Urease, which induces the formation of ammonium car- bonate from urea, and the newly discovered “‘zymase ” of Buchner—the alcohol producing enzyme. It is, of course, impossible in a review to go far into particulars concerning these numerous forms, of which, moreover, there are many varieties. On reading Dr. Green’s admirable and exhaustive account of them, the student will be struck with the prominent position which the study of plants occupies in the elucidation of the properties of enzymes. It has been far too fashionable in this country to regard enzymes and the study of fermentation as if they were in some way specially ac- credited to the domain of the chemist, whereas inasmuch as any such specialisation can be insisted upon, the study is far more within the domain of the botanist and the physiologist, a fact very clearly brought out in this book ; as are also many of the important bearings of the study on the numerous applications of botanical science in the arts. Secondly, it is worth remarking, in full view of the industrious and valuable work done by able continental botanists and physiologists, how conspicuous are the researches of English investigators in this department of science during the last few years, denoting a phase of activity on the part of our physiologists and botanists which promises well in the future. The author has collected a long list of authorities, and since he has made the study of fermentations peculiarly his own for some years, we may accept the literature as practically com- plete. At the same time, in view of the remarks on p- 75, we should have expected some quotation of Mr. Parkin’s recent and important paper on the inulins in monocotyledons. In view of the modernity of the study of enzymes, we NO. 1555, VOL. 60] can hardly be surprised at the lack of any complete deductive explanation of their action, though one of the most interesting sections of the book is that discussing the various hypotheses raised. Our ignorance of the constitution of enzymes no doubt stands at the bottom of this, and it is not at present clear what is meant by a soluble enzyme or by solution. But the fatal blocks to progress in the study of their constitution so far have been their instability during separation, and the un- certainty as to their purity ; consequently the analyses so far attempted cannot be relied on, and we do not even know of any enzyme that it is proteid in nature. All we can be sure of is that a given watery extract washes out from living protoplasm a something—which we term an enzyme—which is capable of converting enqrmous masses of some other body—e.g. sugar—and can itself be mechanically precipitated, re-dissolved and so on. This precipitate may even be dried and retain its specific powers on re-solution. Whether the precipitate consists principally of the enzyme itself or of some body or bodies to which it is attached, is an unsolved question. But when active and in solution, it is significant that the properties of an enzyme can be destroyed ina few moments by raising the temperature beyond a (relatively low) maximum, and that the activity rises and falls with a scale of temperature between the limits; on the other hand, it differs from a living organism in being capable of exerting its specific power in presence of an antiseptic. In the discussion regarding fermentation as a chemical process, these facts should not be overlooked, and it is as true to-day as it was in Pasteur’s time, that you can- not have fermentation without life. No matter how “ dead” an enzyme may be ; no matter whether its remarkable energy consists in surface-actions or in vibrations propagated through the solution, in tem- porary chemical unions and disunions or in electrical hydrolysis ; and no matter what its chemical analyses may imply as to its proteid nature—the fact must be maintained that enzymes are built up by living proto- plasm, and normally exert their best actions in con- nection with the living cell. In many respects, indeed, they suggest essential bits of the protoplasm, and in many ways remind us that we have not yet done with the physiological or “ vital” theory of fermentation, and this will, we think, strike most readers, though perhaps Dr. Green’s summing up inclines more to the view that fermentation is a purely chemical process. Not the least important prop to the chemical theory of enzyme-action is furnished by Croft Hill’s recent work on the action of maltase or glucase on malt-sugar, and his remarkable discovery that a reversal of the enzyme-action may occur, reminding us of the reversals occurring in certain chemical processes. Here, however, we must stop. It is not necessary to recommend the perusal of the book to all interested in the subject, since it is indispensable to them, and we will merely conclude by congratulating the Cambridge Press on having added to their admirable series of Natural Science Manuals an eminently successful work on so important and difficult a theme, and the author on having written a treatise cleverly conceived, indus- AuecustT 17, 1899] NATURE 363 triously and ably worked out, and, on the whole, well written. At the same time, it should be pointed out that such a work was especially in need of a good and exhaustive index, and that it is a pity the author did not compile one himself. CALCULATION BY ABACUS. Traité de Nomographie. Par Maurice d’Ocagne. xiv + 480. (Paris: Gauthier-Villars, 1899.) HIS is a book which ought to make even the ordinary reader appreciate the perennial fresh- ness of mathematics. The method of ‘“‘ Nomography ” (X3 of the international catalogue), recent as it is in its more important developments, is based upon a very simple idea which has long been familiar—that of the indexed scale. The ever-recurring problem of applied mathematics is to calculate an unknown numerical quantity from its relation to other quantities that are known. The simplest case is when two quantities x, y are connected by a relation /(x, y)=o or y=(x). For practical purposes it is convenient to have a permanent record of a large number of corresponding values of + and y so that for any given value of + the approximate value of y may be at once found or obtained by simple interpolation. Three methods are available: the first is that of a numerical table, such asa table of logarithms ; the second that of the graph, for instance the curve f(x, y)=0 or y=$(x) referred to rectangular coordinates ; the third is that of the indexed scale, that is to saya straight line or curve at different points of which the corresponding values of + and y are shown infigures. A familiar example is given by a thermometer with Centi- grade and Fahrenheit readings, or by a measuring tape with centimetres marked along one edge and inches along the other. In this very simple case the advantage of the indexed scale is not very obvious; even here, however, the method combines much of the vividness of the graph with a considerable saving of space. It is when three or more variables are connected by a relation that the great value of the scale method becomes apparent. Suppose, for instance, we have a relation Fig(x), x(¥), ¥(2), a(Z)}=0 where +, y, 2, f are the variables and F, 9, y, W, are known functions. The essence of the nomographic function consists in first plotting off in a suitable way in- dexed scales of (x), x(y), ¥(z), (2), and then employing a linkage or similar mechanism to associate four corre- sponding values, x’ y’, 2’, ¢. In the case of two variables x, y the “linkage” consists merely in the juxtaposition of the scales; when a proportion sum is done with a slide-rule, the scales are moved relatively to each other ; in most of M. d’Ocagne’s illustrations, involving several variables, the scales are either superposed in a two- dimensional grating or a movable linkage is used con- sisting of a transparent sheet with lines of reference ruled upon it, or a combination of both devices is employed. Of course a method so elastic leaves ample room for ingenuity in constructing an “abacus,” as M. d’Ocagne calls it, suited to any particular problem. The author NO. 1555, VOL. 60] Pp. gives an abundant variety of illustrations, many of great practical importance to the physicist and engineer : it is by studying these, and actually taking readings for him- self, that the reader will succeed in appreciating the value of the method. For of this, as of other graphical methods, it may be said that merely reading it up, or understand- ing its principles in ‘a general way, is of little use as compared with a thorough working knowledge of its application. At the same time, M. d’Ocagne has done really good service in devoting his final chapter to the general theory. This has, in its way, the same kind of special value as Reuleaux’s “Kinematics of Machinery” in relation to the ordinary treatises on mechanism. For in this chapter we have a clear conspectus of the general principles which underlie the construction of ay abacus ; and, what is still more remarkable, all possible varieties of abacus are classified into perfectly definite types which can be expressed by a simple abstract notation. Oddly enough, the enumeration of the different types leads to a difficult problem in the partition of numbers, happily solved by Major MacMahon. It is not impossible that the human race may ulti- mately set off against the ravages of warfare the indirect stimulus which it has given to mathematics; nomo- graphy, at any rate, has been developed in great measure to meet the demands of civil and military engineering. M. d’Ocagne’s numerous bibliographical notes will enable his readers to follow in detail, if they wish, the history of the subject. Pure and applied mathematicians alike will be grateful to him for a work so full of novelty and interest ; while its subject-matter, as well as its clearness and simplicity, ought to make it eminently acceptable to the engineer. Ga Be Mi. OUR BOOK SHELF. Die Spiele der Menschen. By Karl Groos. (Jena: G. Fischer, 1899.) Pror. Groos will add by the present volume to the reputation he has already earned by his well-known work on the “‘Games of Animals.” Gake OUR BOOK SHELF. A Short History of the Progress of Scientific Chemistry in ourown Times. By Prof. W. A. Tilden. Pp. x +276. (London: Longmans, Green, and Co., 1899.) IN size and scope Prof. Tilden’s short history recalls Wurtz’ brilliant little “History of Chemical Theory,” published thirty years ago. But whereas the key-note of Wurtz’ book was the ‘immortal memory” of La- voisier, and its main theme the vindication of French chemists contra mundum, the spirit of Dr. Tilden’s bool. ies in its impartiality and sound judgment. In mode of 388 treatment, too, the authors differ. Wurtz, with more personal touches and controversial points, traces the main ideas of chemical combination from the time of Lavoisier continuously to his own ; Prof. Tilden, adopt- ing the more natural lecture method, has given us separate histories of the main lines of chemical progress during the Victorian era. We cannot doubt but that the student will find the modern book handier to consult, and sounder, though possibly less stimulating, than its predecessor. The difficult task of selection has been, on the whole, successfully met by Prof. Tilden. We can heartily com- mend for its lucid treatment the chapter on stereo- chemistry, and ‘the classification of the elements” for its historical completeness and common sense. The few slips we have observed are mainly printer’s errors, e.g. the date of the “Sceptical Chymist” is given as 1680 (p. 38). In the account of Dumas’ experiments on the composition of water, we are told that the reten- tion of hydrogen by the reduced copper was unsuspected in Dumas’ time (p. 80) ; but Dumas himself refers to this error in his original paper. Prof. Tilden repeats the usual derivation of gas, ‘‘ Gas=geist=spirit.” But since the publication of “Gas” in Dr. Murray’s Dictionary we thought the derivation from chaos had been accepted. Perhaps we may quote the full passage from Van Hel- mont, which occurs in the ‘“'Progymnasma Meteori” (p. 69, ed. 1682): ““Verum® quia aqua in vaporem, per frigus delata, alterius sortis, quam vapor per calorem suscitatus ; ideo paradoxi licentia, in nominis egestate, halitum illum gas vocayi non longe a Chao veterum | secretum.” La Géologie Expérimentale. Par Stanilas Meunier, Professeur de Géologie au Muséum histoire naturelle de Paris. Avec 56 figures dans le texte. Pp. 306. (Paris: Félix Alcan, 1899.) IN this work, which has just been added to the “ Bib- liotheque Scientifique Internationale,” Prof. Meunier has aimed at supplying a complete and _ practical series of experimental illustrations of as many dif- ferent geological phenomena as_ possible — in this respect going even farther than did the late M. Daubrée in, his - classical‘ Etudes Synthétiques de Géologie Expérimentale.” The work is founded on a course of lectures given in Natural History Museum of Paris in 1898 ; and in the Geological Gallery of the Museum in the Jardin des Plantes may be seen the actual apparatus, designed by. the author and others, for carrying on the experiments described in these pages. After a general introduction on the value and limits of. the experimental method as applied to geological teaching and research, in which the author replies very effectively to the ‘objections which have been raised to it, he proceeds to treat systematically with the questions involved in, supplying experimental illustrations of geo- logical phenomena. He first deals with the results pro- duced by the action of external forces operating on the eaith’s crust. These are classed as the phenomena of denudation and of sedimentation. Under the first head are classed the action of rain, of rivers, of the sea and lakes, of ice, of subterranean waters and of the wind. It is noticeable that the experiments, many of which are of a novel character, are for the most part such as can be performed with very simple apparatus, of a kind which any ingenious lecturer may readily provide himself with at a relatively small cost, and the experiments are certainly calculated to give point and value to the teaching they are intended to illustrate. The various kinds of sedimentation are treated of in the same way, the action of rain, rivers, seas and lakes, sub- NO.1556, VOL. 60] NATORE [AuGusT 24, 1899 form new rocks being successively handled. In the second part of the work we have a series of experiments to illustrate the action of the internal forces at work on the earth’s crust. The origin of crystalline rocks, in- cluding illustrations of vitrification and devitrification, metamorphism, both contact and regional, and the origin of mineral veins are discussed in a somewhat summary manner, with reference chiefly to work that has been carried on in France ; and this division of the book ends with a rather speculative chapter on the more deeply- seated materials of the globe. The third part of the work deals with volcanoes, earthquakes and the produc- tion of mountain-chains. Although the treatment of the various questions is—perhaps necessarily—somewhat unequal, no teacher of geology can fail to gather from this work of Prof. Meunier many useful hints which will prove of great value in illustrating the action of the various forces which have contributed to the production of the features of the earth’s crust, while the student and general reader will find it equally full of suggestiveness and novelty. The Fauna of Shropshire: being an Account of all the Mammals, Birds, Reptiles and Fishes found in the County of Salop. By H.E. Forrest. Pp. viii + 248 + vi; illustrated. (Shrewsbury and London, 1899). THIs little book, excellent in its way as a local vertebrate fauna, is somewhat more than its title implies. It gives, for instance, a very well-written and interesting account of the habits of many species of British mammals, more especially the smaller and commoner kinds. Particular attention may be directed to the life-histories of the mole and the shrew, some of the facts in the former being new tous. The great feature of the book is the very excellent account of the mode of development and general habits of the British Amphibia ; this group of animals being apparently the author's favourite subject of study. The reptiles are treated nearly as fully as the frogs and newts ; and here we may notice that the author considers that the legend of the viper’s swallowing its young may prove to be based on fact. A much smaller proportionate amount of space is devoted to the birds, for the reason that the author hopes to elaborate this portion of his subject on a future occasion. Although the illustrations, which are chiefly taken from mounted groups, are less satisfactory than they might be, the work may be commended not only to the naturalists of Salop, but to those of the British Islands generally. Rowe La Pratique du Maltage. Par Lucien Lévy. (Paris : G. Carré et C. Naud, 1899.) THIS work, which may be classed as belonging to the best type of modern technical literature, is based ona series of lectures given by Prof. Levy at the “ Institut des Fermentations de Université Nouvelle” of Brussels. At present there is a very open field for such a book, for during recent years no other work devoted specially to malting has been published which attempts, like the one before us, to combine the scientific and practical sides of the question. The work will have most value to readers in this country for the very complete account it contains of recent scientific work connected with germination ; this is given in a very clear and concise form, and the most recent researches of any importance are referred to. The more technical portions of the book bear a conti- nental stamp, and in certain places lead us to think that there are some things connected with malting we do better in England. However this may be, the work as a whole is recommended to those interested in malting as Pp. 248. _ Yain } 5 | the best technical treatise on the subject at present pub- terranean waters and wind in accumulating materials to | lished ; but it should be borne in mind that it is specially AucustT 24, 1899] NATURE 389 written for students on the continent, where the method of malting differs somewhat from ours. The printing, paper, and binding of the book are particularly good. Ae B: By Shelford Bidwell, Curtosities of Light and Sight. (London: Swan M.A., LL.B.,F.R.S. Pp. xii + 226. Sonnenschein and Co., Ltd., 1899. MANY readers will be glad to possess this collection of essays, in which Mr. Shelford Bidwell describes some of the experiments which the scientific world owes to his ingenuity. The five chapters in the volume are based upon notes of lectures delivered to various audiences ; and their subjects are: light and the eye, colour and its perception, some optical defects of the eye, some optical delusions, and curiosities of vision. Each subject is pre- sented with freshness of style, and elucidated by many simple and convincing experiments. To the popular lecturer on science, who desires to know how to produce curious and instructive optical effects, the volume will be very acceptable, and every physical experimentalist may confidently turn to it for inspiration. But though the curiosities of colour phenomena, and of sight generally, are chiefly described in the book, many questions of deep interest to students of both physical and physiological optics are discussed, so that the volume appeals to scientific as well‘as popular readers. LETTERS TO THE EDITOR. [The Editor does not hold himself responsible for opinions ex- pressed by hts correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts tntended for this or any other part of NATURE. No notice ts taken of anonymous communications. | A Curious Salamander. THE artificial propagation of food fishes is an important part of the work of the United States Fish Commission, and for this purpose it has a number of hatcheries or ‘‘ stations” scattered throughout the Union. At each of these stations especial at- tention is given to the rearing of the fishes best adapted to the region in which that particular station is placed, as it would be useless to breed salmon or trout for the warm, sluggish streams of the South, or to put bass and carp into the cold, swift rivers of New England or of Michigan. The sea stations are devoted to the study of marine zoology, and the propagation of shad, mackerel, cod, lobsters and similar organisms that cannot be bred in fresh water ; while hatcheries have been put on the banks of several lakes at which whitefish, land- locked salmon, lake trout and the like are reared. A few years ago a station was established near the town of San Marcos, Texas, for the culture of black bass and ‘‘crappies.” A prime essential for fish hatching is a copious supply of water, and the supply should be as uniform in amount, temperature and composition as it is possible to obtain. If there be much sediment in the water, it will be deposited on the eggs and suffocate them; and sudden variations in temperature may also be fatal. As the rainfall in western Texas is untrustworthy, the Commis- sion determined to bore an artesian well to supply the water for its new station. The well was bored successfully and a flow of twelve-hundred gallons per minute obtained from a depth of 188 feet. There are several such wells in this region that give this amount or more, but soon after the San Marcos well was opened a number of living animals began coming up with the water. So far, four kinds of Crustacea and a salamander have been seen, and of these quite a number have been obtained. The Crustacea are new to science and were described by Dr. James E. Benedict, of the Smithsonian Institution. They are white and perfectly blind. Most of the shrimps and crab-like animals have eyes NO. 1556, VOL. 60] 2.— Tyfhiomolge Rathbuni, } life. set on the extremities of stalks that project above the surface. The shrimps from this well have the stalks, but the eyes have disappeared. The most remarkable creature that has come from the well is the blind salamander, the 7yphlomolge Rathbuni. The name Fic. 1.—Typhlomolge Rathbuni, seen from above. (Photographed by W. P. Hay.) is compounded from the Greek typhios, blind, and mo/ve, a kind of salamander ; while the second term was given in honour of Mr. Kichard Rathbun, the Assistant Secretary of the Smith- sonian Institution, and for many years the Chief of the Division (Photographed by W. P. Hay.) of Scientific Inquiry 01 the Fish Commission. This animal is a new species and a new genus. It was described by Dr. L. Stejneger, of the Smithsonian Institution. The Zyphlomolee is from three to four and a half inches in length. It has a large head, protruding forward into a flattened snout that bears the mouth. The eyes are completely covered by the skin, and are visible from the outside only as two black specks. Just behind the head are the gills. These are external and stand out in festoons about the neck, instead of being covered by a lid as in fishes. The skin isa dingy white, and the sharp contrast between 390 ‘the colourless skin and the vivid scarlet of the exposed gills makes the appearance of this subterranean visitor striking in the ‘extreme. It has four long, slender legs, that are gruesomely ‘human in appearance, and are supplied with feet that are startlingly hand-like. The fore feet bear four fingers or toes and the rear ones have five, and though the legs are extremely slender, they possess a considerable amount of strength. Behind, the body terminates in a flattened tail that bears a fin like that of an eel. In April 1899, two living specimens of this strange being were shipped by mail from San Marcos to the head office of the Fish ‘Commission in Washington. They bore the journey of nearly 1800 miles, and reached their destination in good condition. They excited great interest, and for some time after their arrival a wondering group of spectators crowded about the aquarium into which they were put. These living specimens corrected several errors that had been made from observations of the dead bodies only. The legs are used for locomotion, and the animals creep along the bottom with a peculiar movement, swinging the legs in irregular circles at each step. They climb easily over the rocks piled in the aquarium, and hide in the crevices ‘between them. All efforts to induce them to eat have been futile, as has also been the case with blind cave fish in captivity and they are either capable of long fasts or live on infusoria in ithe water. From whence do these strange creatures come? The well is sunk in limestone, and that renders it likely that there may be some great cavern or subterranean lake communicating with it, ‘but the rock through which the hole is bored is solid, except for a single channel two feet in diameter. The fact that the water rises nearly two hundred feet shows it to be under great pressure, and altogether this well affords material for study to geologists as well as zoologists. Washington, D.C. CHARLES MINOR BLACKFORD. Palzolithic Implement of Hertfordshire Conglomerate. THE rudely-made Palzolithic implement, illustrated to half the actual size in the accompanying engraving, is probably unique in the highly intractable material from which it is made. It was found by me in May last with Palzeolithic implements of flint in the Valley of the Ver, Markyate Street, near Dunstable : its weight is 1 lb. 640z.—1677 in my collection. Although rude, there is no doubt whatever as to its true nature; there isa large bulb of percussion on the plain side, as seen in the edge Fic. 1.—Palaolithic implement of Hertfordshire Conglomerate. One-half actual size. view, and the hump-backed front is chipped to a rough cutting edge all round, each facet going right through the embedded pebbles. Its condition is totally different from a newly-broken block of Conglomerate, and indeed of Conglomerate broken in Roman times by quern-makers., It is faintly ochreous from being long embedded in clay, and sub-lustrous. _Newly-broken Conglomerate is in colour a lustreless cold grey. The peculiar mature of the material would not admit of finer work : I have NO. 1556, VOL. 60] NATURE [Aucust 24, 1899 tried hard to flake Conglomerate without the slightest success ; it breaks only after the heaviest blows, and then in the most erratic manner, the embedded pebbles often flying from the matrix. Sir John Evans has seen this example, and agrees with my conclusions as above expressed ; he also informs me that several years ago he found what appears to be the point of a lanceolate implement of the same material and of Palzolithic character on the surface of a field near Leverstock Green. Dunstable. WorTHINGTON G, SMITH. On the Calculation of Differential Coefficients from Tables Involving Differences; with an Interpolation- Formula. (1) In Narure for July 20 (p. 271) Prof. Everett has given formulz for calculating first and second differential coefficients in terms of differences. The formule can be more simply expressed in terms of ‘‘central differences.” Let the values of a function #, be given forx=..., —2, —I, 0,1, 2,...3 then, with the usual notation, Aly = 2, — Uy Atty = Atty — Arty = tty — &e, 22) + Moy Now write 2(Arly + Au_,) A*u_, 3(A%2e_, + A3z_, Atz_, &e. Then a, 4, co, %-- are the ‘central differences ” of 2. Take, for instance, the following table :— , y ev A 47 109°947 13563 4'8 121510 12780 1217 126 ae a 16 be m5 909 16 I 155 I oS ore L/Z50 181 wh ae 2c 200° j WEDS 2008 m9 Fy 23 ooreee 2) aoe 213 18 oe eae 23286 Bae 231 swineg = A 2573 5 2 ae Writing y = 5°2+ ‘Ix, and #,;=10%e”, so as to get rid of decimals, we have the following values corresponding to a—25-2 (4 — 10) tae Uo x b5 a) a) & 181272 181574 1815 1814 15 24 With this notation, the value of 2, for values of x between — 4 and + 4 is given by oe x(x? — 1) x? (x2 Ug = Uy + XA 2 by + ( ) @ ( Boh (bb) This is a well-known formula. Differentiating with regard to x, and putting « = 0, we have (writing zw for z,) au “7 4 7 () = & — so + 30% — trav So + a. 0 < Similarly, differentiating twice, and putting + = 0, shes 5 a Pac (@) = by ake china skuo + = we nelle) ax] o “cc Prof. Everett’s formula for the ‘‘increase-rate”’ when fifth differences are negligible is obtained by taking the first two terms of (ii.). (2) The advantage of these formule, as Prof. Everett points out, is their greater accuracy. The ordinary formula A—$A*+ §A* — fA*+ 3A5, in the above example, would give for y=5:2 au =181314, ax while, if the differences were taken backwards, we should get Ut Bil 181241. ax Aucust 24, 1899] NATURE 392 The formula (ii.), taken to the fifth central difference, gives = 181273, ax the true value being du 4 — = 18127°224. ax The inaccuracy in the ordinary formula is, of course, due to the fact that a table such as the above never gives the exact value of the function tabulated, but only the nearest integral multiple of a certain unit (in this case oor). If we denote this unit by p, each tabulated value differs from the true value by some quantity lying between —4p and +4p. It may be shown that this makes it possible for A—4A®+4A*°—4,% to differ from its true value by as much as 4;°p, while @)—4co cannot differ from its true value by more than }p. Hence this latter formula is more accurate than the ordinary one in the ratio of 64:9, or about 7:1, when fifth differences are negligible. When only seventh differences are negligible, the formula ay—%ty+ 356 1S” more accurate than the ordinary formula, in the ratio of 832: 55, or about 15:1. (3) The formule (ii.) and (iii.) give the first and second differential coefficients for the values of the “‘ argument ” shown in thetable. It is often more useful to have them for the zzfer- mediate values. This requires a modification of the method of central differences. Let us write (2; + 24) =V Ary =A) F(A22) + A220 4) =Ay [STs As &e. Thus for the interval from 5°2 to 5°3, in the above example, we have V Ay Ay A; Ag As 1908044 19065 1909 189 19 9 With this notation, it may be shown that, for any value of x from 0 to I, I-—2¥ t= {Ve = a,} x(1- I-2x a x) A-"gAs} x(1 =a?) (2—2) E20) ) 4! ita 10 Shh a(I —4*) (4 -—«*) (3-2) I-24 = 5! {40> 14 4; ome BRE she: S. « ts 5.) SK bWS)) Or, if we write x=4+0, then for values of @ from —4 to +4; yh 49=1V +0A}} I-46" ~ "Ha {a+ $A} 1 — 46") (9 - 46° vl 46°) (9 - 46°) vaA Nt { ai+204 | : 00 4 o Gen) Differentiating this last expression twice with regard to 6, and putting @=o0 we find du 2*. 4! 3 5 I . Taya Oa ayhet os og t © eens (Ve) au\ _ 5D), 3229. Bs Ales 2444+ 576046 — 32256048 + . Gears (vii.) Thus for y=5°25, in the above example, we find du _ fe 19057°17, the true value being (4) The ormula (iv.) is useiul for constructing tables by means of interpolation. For halving the intervals in a table, it gives y= V —}Ao4+-3,A,- 9 a, +—35_ag— . s "EESe- bio24° 3276810 NO. 1556, VOL. 60] on (viii. ) Similarly, for subdivision of the intervals into fifths, # =V— "3A, — ‘08A, + ‘008A, + ‘0144A, — ‘0008644; / — *0029568A, + °00012672A, + °000642048A,— . #2=V — “1A, — "12A,+ "004A, + °0224A, — °000448A,; —*0046592A, + ‘00006656A, + ‘OOIOI8368As— ... ux3=V+ "IA, —"I2A,— ‘004A,+ Kc. us=V + “3A, — 08A,— ‘008A,+ Ke. ; (ix. ) the terms in w; and ws being the same as in we and 2, but with signs alternately alike and different ; and the sequence of signs in each case being... ++—-—++ ... The corre- sponding formulze for subdivision into tenths might be found = poe is simpler to subdivide into halves and then again into ths. When several differences have to be taken into account, the above method of direct calculation is less troublesome than the ordinary process of building up the table by calculation of the sub-differences. In the formulz (ix.) the terms due to V and A, have been given in the form V-—°3A,, V-—‘1A,,.. . ; but in practice these terms would be obtained by successive additions of ‘24 to w%p, so that it is not necessary to calculate V. August 16. W. F. SHEPPARD. Apparent Dark Lightning Flashes. ON the evening of the 5th of the present month we were visited by a severe thunderstorm, which passed practically over this place. The lightning was very vivid and at times occurred at intervals of only a few seconds. In order to photograph some of the flashes I placed a camera on my window sill and exposed four films for consecutive periods of 15 minutes each. During the exposures I was observing the sky, and repeatedly found that after nearly each bright flash I could see distinctly a reversed image of each flash zz any part of the sky to which I turned my head. These apparent dark flashes, or rather the images on my retina, lasted for sometimes 5 to 10 seconds. At the time I wondered whether dark flashes had ever been noticed before, and thought that this phenomenon was not un- commonly observed, but seeing Lord Kelvin’s letter in your issue of August 10, I send this note in case it may prove of interest. Westgate-on-Sea, August13. WILLIAM J. S. Lockyer. Subjective Impressions due to Retinal Fatigue. IN reading the interesting optical experience as described by Lord Kelvin in NATURE of August 10, it occurred to me that a somewhat similar effect on the eye, as noticed by myself, might be of interest. Frequently late in the evening, and with a dull cloudy sky, I have seen my own figure, at least in part, apparently projected in gigantic form high up on the cloudy background. This happened in the following manner. Going to the door of the house, and standing there with the strong light from the lobby or hall lamp shining out upon the gravel-walk in front, I saw my figure in shadow strongly defined upon the illuminated pathway. On raising my eyes quickly to the sky, I there saw the same form marked out on the dark clouds, but in a lighter shade. The effect on the eye, as in Lord Kelvin’s experience, is- doubtless that of fatigue : in my experience, however, the form observed being very dark as compared with the illuminated. bagkground, I received the complementary impression of a. light-coloured figure on a dark background. The time during which this impression remained when look- ing at the clouds might be a couple of seconds. August 14. W. J. MIniar. Mathematics of the Spinning-Top. Ir should have been stated on p. 321 that, while 6, is the angle between HQ and HQ’ in Fig. 1, p. 347, the angle between HS and HS’is @. At the same time this opportunity is available for some corrections, for which the printers are not responsible. On p. 321 the values of sin @; and sh @, should be interchanged ; on p. 348, after equation (35), read ... ‘* MX is the harmonic mean of MT, MT’ and of Mm, Mv’, ...” August 12. A. G, GREENHILL. Calcium 39 ON SPECTRUM SERIES. Il. I" is well that I should indicate the basis of these | statements, and for this purpose I throw onthe screen | a very small part of the spectra of two or three different | substances in order that you may see the way in which the work has been done. Take the lowest horizon. There we are dealing with zinc, and you see the way in which the triplets have been picked out. The triplet in | each case, of course, supposing it is the remnant of a | fluting, has its central line nearer to one side of the triplet than the other. All the triplets in the zinc spectrum are perfectly symmetrical from that point of view. If we | take the upper spectrum—that of calcium—we find also that the triplets are formed in exactly the same way. We can quite understand the enormous labour which has been involved on the part of the inquirers I have named | in working out from the spectra of a great many sub- stances and from all the different regions of the spectrum, visible and photographic, these delicate triplets. In a Cadmium Zinc Nb Vik E [AvucusT 24, 1899 was far more simple than that of any other chemical elements. A short time ago, however, Prof. Pickering, in his magnificent work on the stars, to which I have already had the opportunity of referring, discovered a second series of lines. Not long after, Prof. Rydberg suggested that one of the most important lines seen in a large group of stars really represented a line of the principal series of hydrogen. That conclusion has been generally ac- cepted, although the evidence is considered doubtful by some; so that we now assume that hydrogen has three series like helium and asterium, and we seem therefore to be on solid ground in one direction, at all events, in regard to some gases. We have another series of metals of low atomic weight, and which therefore chemically are supposed to represent a considerable simplicity; we find that in the case of lithium and sodium we also deal with three series, a principal series and two subordinate series. The series of lithium are just as beautiful in their rhythm as the other series to which I have referred. The same remark applies ex- | actly to sodium. Now, it has recently been found that +t Vie Soot ——! te me 4 t : ey = eT Te Gia Fic. 6.—Parts of the spectra of calcium,"cadmium and zinc showing the triplets. great many cases they do not represent the strongest lines, those most easily seen, and they want a great deal of looking for. I next pass on to some more general statements, which I am anxious to put before you for the reason that you will not find them stated in any literature that I am acquainted with ; the subject has really not been gener- ally discussed at all. Some substances have three series, as in the case of helium and asterium. There are others like them ; and the most remarkable case which I have to bring before you is that of hydrogen. We do not know the meaning of it yet, but it has to be taken into account in any con- sideration of these questions. Until a little time ago only one series was known in the spectrum of this gas, and it was thought that on that account the atom of hydrogen 1 A Lecture to Working Men, delivered at the Museum of Practical Geology, on May 1, by Prof. Sir Norman Lockyer, K.C.B., F.R.S. (Continued from p. 370.) NO. 1556, VOL. 60] sulphur and selenium also give us three series. We have a principal series and the first and second subordinates, but the suggestion of anything beyond these three is confined to one or two lines in each case. Next let us take another gas, and see what happens in the case of oxygen. Ile have six sertes, that is twice as many as we know of in hydrogen, helium, asterium, lithium, sodium, sulphur, and so on. I should say that so far as that goes we are in the same condition that we were some time ago when we imagined that the gas obtained from the mineral cleveite was really a single gas with six series. Very many arguments have been employed to show that that view is probably not an accurate one ; so that some are prepared to separate the cleveite gases at spark temperatures into two, calling one helium and the other asterium. That brings these two constituents of the cleveite gas then to the same platform as hydrogen with the recent developments, lithium, sodium, sulphur, &c. If we come to consider this extraordinary condition in the case of AucustT 24, 1899] oxygen a little further, we find that the six series only after all pick up the oxygen lines seen at a low temper- ature, and that if we employ a high temperature to observe the oxygen spectrum, that is to say, if we use an induction coil, a jar and an air break, we find a very considerable number of lines indeed which have no connection whatever with the series. And we are face to face with this very awkward fact, that in the case of oxygen there are more lines which we cannot get into a series than there are lines in the six series which we have attributed to that chemical substance. Here, therefore, we begin certainly to get into diffi- culties. The inquiry is not so straightforward, the conditions are not so constant, as we might have expected them to be. Here then we have instead of three series twice that number, and these only account for about half the lines. Now, let us look still a little further. The next point is that in the case of other substances we have no principal series, but only two subordinate ones. This happens in the case of magnesium, calcium and strontium. We have only two series in the case of magnesium, two in calcium, and two in strontium. In all those three NATURE 695 certain number of these lines has been picked up to form the series, but we get numerous lines which have been left over after all attempts to sort them into series have been made. I have now to bring before you another consideration. We are dealing in the case of calcium and magnesium with arc temperatures, but I showed you in my first lecture that in the case of calcium and magnesium the all-important lines in the hottest stars were lines seen at the temperature of the spark. I have added these lines to the diagram, and you will see that there is not the slightest trace of those lines having been picked up in the series. So that the further we go, the more we seem to get away from that beautiful simplicity with which we began. I take you now to another group of substances, namely, tin, lead, arsenic, antimony, bismuth and gold, and I might mention more. No series whatever have as yet rewarded the many attempts of those who have tried to get those metals and non-metals on all-fours with those previously investigated. It remained for Kayser and Runge to point out that it looked very much as if this complete absence of series was connected with the melting point of the substances with which they had been dealing. So long as the melting point was low, as in the case of sodium and lithium, the normal three series would show at low temperatures ; and, further, there were no lines over. But, when you get to these substances with high melting points, there is no series at all, and of course it is suggested that there- fore there must be intermediate stages ; and that really seems to be a very valid suggestion indeed, and one which in all probability will enable us to get over some of the difficulties. They point out that in the case of lithium, sodium, pot- assium, &c., all the lines are picked up, and that in the case of copper, silver and gold the series pick up only a very small proportion. There seems, therefore, to be a progression of complexity with the in- creasing melting point with regard to all the metallic substances which have so far been examined; of course this consider- ation does not touch the question of oxygen. Oxygen is a gas, hydrogen is a gas in con- Fic. 7.—Map showing series and residual lines in spectra of calcium and magnesium. we have a first and second subordinate series, but no principal series, I have studied the lines of calcium and magnesium, in the same way that the lines of oxygen were studied to see how many of the lines are picked up by the series. In the upper part of the diagram we have the lines seen in the arc spectrum of calcium, and in the two next horizons we have the lines picked up in the first and second subordinate series. The next horizon gives the residual lines—lines, that is, which have not been distributed into any of these series. You see that there is a large number outstanding just as in the case of oxygen, and it is very important indeed to note that the two lines H and K, which are more conspicuous in the spectrum of the sun than all the other lines of the spectrum, have not been caught by any of these re- searchers into the series of calcium. Therefore, with a reduced number of series, we seem to be getting still further from the simplicity we began with in the case of some of the permanent gases like hydrogen and helium. The same thing holds with regard to magnesium, | the spectrum of which at the temperature of the arc has not so many lines in it as the spectrum of calcium. A NO. 1556, VOL. 60] | the case of lithium. sequence, of course, of their very low melt- ing points, and you know that quite recently it has been found possible to liquefy both of them. So that there must be something different in their case, and it seems extremely encouraging to find, therefore, that the same variation, the same break- ing away from the law which I pointed out in the case of some of the metals, should really occur also in a gas, because it seems as if we shall be able to explain the phenomena in both cases by supposing that there is a condition of greater complexity, and that when we follow up this line of greater and greater complexity, whether in a gas such as oxygen, or ina solid such as gold, we do not get the simple series, because at the temper- atures we employ we are still far from the simple con- dition which we can get at in some gases and in some metals with low melting points. The table gives the relation between the melting point and the percentage of lines sorted into series. Thus, in the case of barium with a high melting point we get no lines at all represented in the series ; then we gradually get up to Ioo per cent. in But then again, as in the case of oxygen, when we come to mercury, which is also of low melting point, instead of getting 100 per cent. we only get about 25 percent. of the lines represented in the series. 394 Relation of series to melting points. ey go | Element Melting point | Peréentae cio Barium ... 1600° | fo) Gold 1200 4 Copper ... 1050 6 Silver =| 960 26 Strontium... 700 20 Caletump- ee 700 34 Magnesium ... | 600 64 Zin@ wae. saree 410 So Cadmium... | 320 50 Lithium... ... 180 100 Sodiumjy-., /-- feo) 100 Gesium... ... 62 100 Potassium... | 58 100 Rubidium... | 38 100 Mercury... | — 40 27 These matters, of course, have been very carefully inquired into, and among them I will just point out that Meyer has shown that if the wave-lengths of all the lines for z=co be calculated and put as ordinates, and the atomic weights as abscissee, then all the points lie on a curve similar to that which gives the atomic volumes as functions of the atomic weights. He not only deals with the melting points, but he goes further and attempts to associate the melting points with the atomic weights. The next consideration is that in these investigations, in some cases, the series have reproduced the same chemical group, but in some instances the series group- ings, so to speak, are quite different from the chemical groupings. The facts so far ascertained are as follows :— Group I Lithium, Sodium, Potassium, Rubidium, Ceesium. 33. 2 «| Copper, Silver, (Gold! ?). 3» 3 + Magnesium, Calcium, Strontium. al Zinc, Cadmium, Mercury. eS Aluminium, Indium, Thallium. In the group of lithium, sodium, potassium, the series sequence follows absolutely the chemical sequence. But when we come to the chemical group—calcium, strontium, barium—you find it replaced by a group, magnesium, calcium, strontium, while barium is not used at all. That is avery remarkable departure, and it shows that we have to consider the various conditions which we observe in passing from group to group. From group to group with increasing atomic weights the series back towards the violet. Thus, as the limit of a series is represented by the first constant for the first subordinate of the four groups, the limit lies Between 2858'6 and 1974°3 for Lithium, Sodium, Potassium, Rubidium, Czsium, a 3159°I ,, 30782 ,, Copper, Silver, Gold. 59 3979°6 ,, 3103°0 ,, Magnesium, Calcium, Stron- tium. A 4294°5 ,, 4015°9 ,, Zinc, Cadmium, Mercury. In each growp with the increasing atomic weight the spectrum advances continually towards the red end ; that is, in exactly the opposite direction we observed before. Having dealt with these details, there are several other general questions which I should like to say a word about, because it is evident that we are here in presence of the beginning of a new attack on the nature of the chemical elements. Let us attempt to compare these simplest results obtained by this newest form of spectrum analysis, in other words the simplest series, with the earliest stellar forms. NO. 1556, VOL. 60] INGA Re E [AucusT 24, 1899 We found that the hottest stars contained hydrogen, helium, and asterium. Well, we have found that those substances have the simplest series ; that is to say, one set of three. I told you that it was more than probable, although it is not absolutely established, that the lithium group of metals is also represented in stars of very high temperature. There, again, we have the simple series of one set of three. About sulphur we do not yet know positively, but it is probable, I think, that sulphur may exist in the hot stars. There, again, we get another simple set of three; so that for three perfectly certain members of the hottest stars, together with one in all probability and one doubtful, we are dealing with the simplest series in the hottest stars. But now comes the remarkable fact that side by side with these simple substances we get in the hottest stars magnesium and calcium. We cannot suppose that the absence of the principal series there means a greater simplicity, because I have shown you that only about half the lines in the spectrum of each of these substances has yet been picked up in the series, and if the series. represent the vibrations of a single particle, of course the lines which are not represented in the series, by theory must represent the vibrations of some other particles. So that there we are face to face with the possibility of a much greater complexity. Coming a little further down in stellar temperatures we find oxygen, and here we deal with six series instead of three, or two, as in the case of magnesium and calcium ; and even then, as I have pointed out to you, we do not deal with above half the lines of the gas as we can see them at a higher temperature. This, then, seems to suggest that in the hottest stars there are very various stabilities of very various forms. In fact, there seems to be there as here distinctly the survival of the fittest ; otherwise how can we account for the fact that certainly in the hottest stars we get two metals, magnesium and calcium, before we have indication of any other metals, and that where we have those metals and bring our series touch-stone to them we find that instead of being very simple they are really very complex? However this may be, we are now assured that there is a much greater quantity of some apparently more complex forms in the hotter stars than of the more simple ones ; and that is a matter which the chemists, when they come to inquire into these questions which we are now considering, will certainly have to face. This fact suggests, too, another very interesting question which has some relation, per- haps, to some of those drawings that I have thrown on the screen from Lyell’s Elements, which showed that a great many simple organic forms appear in the strati- graphic series ata late period ; that some of the simplest forms died out, others remained. Now, it may be that some of the more simple forms in inorganic evolution, as in organic evolution, really represent later introductions ; but, however this may be, it is perfectly certain that we have not an absolute parallel between the results of the spectroscopic observations of series and the spectroscopic observations of stars. The accompanying table will show very generally how the matter stands. The chief points to refer to are the gaps in the table showing the prin- cipal series and the first and second subordinate series. We have the metals arranged in the order of Mendeleéjeff’s groups. You will observe that after the first metals we practically deal with no principal series at all until we come down at the bottom to oxygen, sulphur and sele- nium. The same thing happens with the subordinate series so far as the existence of single lines and double lines are concerned. Now, it is a curious point that in the case of several of those substances in which no prin- cipal series has been detected, certain lines in the ultra- violet of considerable strength have been observed which may ultimately turn out to represent principal series. Of course, if that should be so it will make the inquiry a Aucust 24, 1899] NATURE 395 very much simpler one than it appears to be at present, and it may possibly break down that terrible amount of uncertainty and irregularity which it has been my duty ¢o point out to you in the series so far examined. there is no fluting from one end of the spectrum to the other.. Rydberg has suggested that an investigation of the so-called “longest-lines” of the various substances may | a au. 22 a a eS Principal series. ist and 2nd subordinate. SoM) as | = = a |3\2 29) a3) Ej ey ae SEE ss] Bg pe 2 “ |"s REMARKS. 2Ey) 3 te pe (|) Boe. | ie iva 3! = 2 | 3 | Single. | Double. | Triplets.|Single. | Double. | Triplet. fetch |b 2 a y | | Z fase | | + | Hyprocen | — | 1/]3)|1] — |Double?) — — | Double} — — Ioo | 100 | — | | | Insub. series the double ly oxt| } represents strong mem- } | ber with faint com- HELIUM ... ae esnier| Single — = — |Double) — panion. Helium really) roo | 100 | — ASTERIUM — | — | 3] rt |Single = — |Single — — gives a spectrum of six, 100 | 100 | — | series, but one set of| | | three series has been) | | called Si Es Eeeros } 70°| 3,\.1 | — | Doubler) ~— — |Double?) — 100 | 100 | 180 ODIUM.... ||| 230/3/1 = | Dou — | Double} — 100 | 100 | 90 Porassium | +I. 39:0 3/1] — | Double} — | — | Double] — pee eae a alll c25¢9) 6a7|b100 58 RUBIDIUM Sear |r | — | Double = Not observed Spe rcnG roo ieies 8 | 5 weights increase. 3 Castum... | J 1353) 2) 0 | — | Double) = Not observed 100 | 100 62 | Each element contains Copper ... | 1634 /2]/o0| — = — — | Double = [ in the ultra-violet a) 6 — |1080°5 SILVER Ir 1076 | 2/0] — — = — | Double = | very strong pair of lines) 26 | — | 960 GoLp 1967 |o}/o0| — = = | Sj) Se -) = { which may be prin-) ? — |1061°7 | | cipal series. | 2852°2 and some pairs MAGNESIUM |) amen nO: —. || ao an — ~- /|Triplets|+ not picked up by these| 64 55 | 600 | | | series. | | | (Some more triplets and CALCIUM Tesg| 2 io! — | = — — — Triplets} pairs not picked up by| 34 17 | 700 | | these series. STRONTIUM | Rreaezalkon|| = | tes — _— — . |Triplets = 20 7 | 700 Barium ... 1368 }o]/o0/ — | = = — —- | = = =) =o) 25 ZINC | 651/2}/o0} — | — = — — Triplets (ae, each “case ben eae 80} 43 | 410 CapMIUM I \rrr7|2\);o0); — | = = = — Triplets pene Ei binaeceeent 50 | 14 | 320 MakeuRy if aieelro| = | ay ia Tri iets, | line in the ultra-violet 27 |12°5 |—40 | pretS\. may be principal series. ALUMINIUM | | S720) | — = — = | Domi) = — — | 25 | 654°5 INDIUM ... FILE. |113°7 | 2 | 0 — _ _ — | Double — — — 25 | 176 THALLIUM | 203°77|2/o0| — — — | — | Double} — | — —| 17 | 282 | | | (No series have been SEUNG. « liv 117‘°8 | 0]}0 —- |) =— -- —} — — || discovered, but there) — — | 232 LEaD ... | f° |206%4 |o0}/0/ — | — — _ —- |} = seem to be groupings) — | — | 326 ARSENIC | 74°9|/0}/0] — — — — == = of lines which recur) — | — | 450 ANTIMONY | ;V. |1196/0/0/ — | — | very frequently. The — | — | 629°5 BIisMUTH i) 207°5|9}/o0} — — — —_— —- | = lines do not form) —J| — | 270 series. OXYGEN. J. 15°88} 6 | (2)) — — {@riplets;) — | —_ |Triplets — Yh = = : | lea These probably have} . Vig) | six series. One strong SULPHUR Bio!3 |r) — — Triplets) — | — (Triplets|) triplet is observed) — | — | 114 SELENIUM | Fry || 3.) I — — Triplets) — — |Triplets|) which may be prin-| — | — | 217 | | || cipal series of second | set of three series. } Another matter of considerable importance to us in attempting to arrange the chemical elements along this line of series—and it is work that is sure to be done now that the matter is once started—is to endeavour to see if there is any strict relation between those chemical sub- stances which give us these simple series and those which are more apt to provide us with those exquisite thythmic flutings. In some of the elements the flutings and the proportions of them from one end of the spec- trum to the other are very remarkable, but in other metals the wonderful thing about them is that practically NO. 1550, VOL. 60] | | | | eventually help us in our inquiries. I will tell you what the longest-line means. If we examine a light source by pointing the spectroscope directly at it, of course the rays from every part of the light source enter the instru- ment ; but if we throw an image of the light source on the slit of the spectroscope, then those particles which exist furthest from the centre will be visible furthest from the image of the centre, and therefore if they are visible enough to give spectra, we should get long lines stretch- ing from the centre to the very limit at which their light is visible enough to be utilised by the instrument. As a 396 IWADURE [AuGusT 24, 1899 matter of fact we do see some very long lines in this way in the case of some substances, and these of course appear to be quite distinct from the shorter lines which are limited to the exact centre of the spark or the arc ; tothe region, that is, in which the very highest temperature is at work. Rydberg has shown that in a considerable number of cases long lines seem to have a very con- siderable importance, and on that account it is well worth inquiring into. Rydberg’s investigations of the members of the first three groups of the periodic system led him to conclude that the long lines form pairs or triplets, which in the case of each element are character- ised by a constant difference (v) in the number of waves of the components. For each group of elements shown in Mendeléjeff’s table, this value he finds increases ina ratio somewhat exceeding the sguare of the atomic weight. What, then, is the general result ot our inquiry, taking series in inorganic evolution to represent the cells which are microscopically studied in the case of organic evo- lution? I think you will agree that the evidence is that, however simple the organic cell may be, the chemical units in the case of any substance represented to us by the movements which are written out by these series must possess different degrees of complexity. I have already told you that a little time ago it was imagined that hydro- gen was rendered visible to us by such simple vibrations that only one series of lines could be produced. If that is so, then it looks very much as if whenever we see three series of lines that three molecules or atoms, three dif- ferent things, are in all probability at work in ‘producing them. When we get six series, that points to a still greater complexity, and when as in the case of oxygen we get six series not accounting for half the lines, then we should be quite justified, I think, in supposing that oxygen was one of the most complex things that we were brought face to face with in our studies of series. When we come to metals where there are no series at all, what do we find ? We find that we are dealing with substances with high melting points—that is to say, we cannot bring them down easily to those mobile states represented by the free paths of a permanent gas; and it is quite easy to suppose, on that account alone, that we do not see the vibrations of any of the more simple forms. Therefore, I think it is perfectly certain that we have not universally got down to the equivalent of the cell-level in our study of chemical forms. With regard to this question of the relation of the two evolutions inorganic and organic, I have still one more diagram which will give an idea of the place of organic evolution in regard to inorganic evolution in the scale of time: I donot want you to pay too much atten- tion to this diagram, because it is-entirely hypothetical ; but it is constructed on the simplest principles, so that it shall go as little wrong as may be. I begin by drawing a line at the bottom, which represents the zero of temper- ature ; certain temperature values are indicated on the left-hand side of the diagram. Then we have the assumption that a star loses an equal amount of heat in an equal period of time. In that way, then, you see at the bottom we have relative times, as at the side we have temperatures, in Centigrade degrees. Water freezes at a certain temperature above absolute zero, and boils at a certain other point ; these are marked on our temperature scale. Then we have to remember that about half-way between the boiling point and the freezing point, all the organic life with which we are familiar on this planet, from the geological evidence and our own experience, must have gone on at a temperature of somewhere about, let us say, from 50° to 40° Centigrade. There, then, we get the limit of organic life in relation to the possible in- organic life, represented by the various chemical changes in the stars. We know from laboratory statements that NO. 1556, VOL. 60] the stars of lowest temperature are about the same temperature as that of the electric arc, which is about 3500° C., and so we put the Piscian stars there. It has also been stated by Mr. Wilson lately that the temper- ature of the sun measured by several physical methods is something between 8000° and gooo’ C.,so that we put there the Arcturian stars. Of course we have no means of determining the temperatures of the hotter stars, so I have ventured to make a very modest supposition that possibly we get about half the difference of temperature between those stars as we have found between the Piscian and the Arcturian stars from experiments on the earth, That will give us roughly something like 5000 C. We find then that if we assume equal increments of temper- ature for each of thedifferent genera of stars that I brought before you in the second lecture, we get a temperature at the top of the diagram of something like 28,000° Centigrade. All we have to do, then, is to draw a diagonal line on which to mark the various temperatures considered. On this the organic evolution, which repre- sents everything which has taken place with regard to living forms on the surface of our planet from the pre-Laurentian times to our own, is represented by a small dot. It looks, therefore, very much as if these recent results of spectrum analysis, which it has been my duty and my pleasure to bring before you in this course of lectures, may probably be of some value in the future, because they deal with a multitude of changes and a period of time compared with which all the changes discussed by the geologists are almost invisible on a diagram of this size. Not only shall we have probably some help in determining this scale, but I think that, as I have already indicated to you, the wonderful similarity between the substances contained in the organic cell and those which would most likely be free when the greatest amount of chemical combination had taken place on the surface of the cooling world, will throw some light on the basis of organic evolution itself. In that way, then, we have really been only continuing courses of lectures given here formerly, which had to do with Man’s Place in Nature, and with ‘the Sun’s Place in Nature ; and | think you will agree that we have found fresh grounds for thinking that the more different branches of science are studied and allowed to react on each other, the more the oneness of Nature impresses itself upon the mind. NOTE ON THE DISCOVERY AND OF GLOSSOTHERIUM DON) JN PATAGONIA} INCE 1877, when I discovered the Tertiary Mamma- lian beds of Santa Cruz, in Patagonia, I haye been looking for proofs of the ancient connection between the new uplifted lands of the southern part of the American continent and: the other lands of the Southern Hem- isphere—Africa and Australia. During my subsequent travels in the interior of the Argentine Republic, in- cluding Patagonia, my interest in that connection has been increasing, and I have discovered additional evi- dence, which showed me the former greater extension to the east, in comparatively modern times, of the actual existing lands. The splendid results of the researches made by the La Plata Museum in Patagonia have re- vealed a greater number of lower forms of vertebrates, including numerous marsupialia, some of which seem to me closely related to the mammals of the Pleistocene fauna of Australia, and among them Pyvotherium and Diprotodon. 1 think that my suggestion has an indubit- 1 By Dr. Francesco P. Moreno, Director of the La Plata Museum. (This article will appear in the Geolog ical Magazine for September 1, and is pointed in advance in NaTurg, by permission of Dr. H. Woodward, F.R.S.) OF MIOLANIA (NEOMYLO- Aucust 24, 1899] NATURE 397 able confirmation in the discovery made by the exped- itions which I sent in 1897 and in the first months of this year, under the direction of Mr. Santiago Roth, expeditions that have had astonishing results. In beds containing remains of mammals and dino- saurians, Mr. Roth discovered in 1897 a caudal sheath- ring, very similar to those of the G/yptodon, but which I at once recognised as pertaining to a form like the chelonian of the Pleistocene of Queensland, described by Owen. I brought this fossil with me to London for comparison with the remains of (/7o/ania preserved in the British Museum (Natural History). The resemblance was great, but the fact of a Tertiary chelonian from Fic. 1.—a, front view of skull ; Megalania prisca by Owen in 1880). Patagonia being analogous to the Pleistocene genus from Queensland and Lord Howe Island was so astonishing that some doubt was permitted ; but, having previously ordered a new examination of the fossiliferous bed where the remains were found, I have now the certainty of the | extremely close relation between the Australian and Patagonian chelonian. I have received several photo- graphs of a skull discovered by Mr. Roth, which photo- graphs, when compared with the Australian specimens in the British Museum (Natural History), give no place for doubt upon this matter. I think that it is sufficient for the present to give two cuts representing the two forms of Mzolania. \ expect in a few days the original specimen from Patagonia, together with various bones and additional remains of the caudal sheath, with some of the carapace. These will be the subject of a special description by Mr. Arthur Smith Woodward, who has so kindly commenced studies on the fossil reptiles in the La Plata Museum. I have also brought with me to London a piece of a skin discovered ina cave near Last Hope Inlet (lat. S 51° 30’), which I have referred to a species of the extinct iWylodon (see “On a Portion of Mammalian Skin, named Neomylodon listaz, from a Cavern near Consuelo Cove, Last Hope Inlet, Patagonia,” by Dr. F. P. Moreno; with a description of the specimen by A. Smith Wood- ward) ; while Mr. Ameghino has announced that another piece of the same skin pertains to a mammal still living, of small size, which he has called Meomylodon. When I took this piece at Last Hope Inlet in November 1898, I was convinced that it was part of the skin of a Mylodon or a form very similar to it, and that the dis- covery was of great importance to me, as I think that the Pampean muds, where the extinct Edentata are found, are of very modern age ; an opinion contrary to that held by another observer, Mr. Ameghino, who refers the Pampean fauna to the Tertiary age. I have already maintained that the extinction of the greater part of the Pampean fauna took place after the presence of man in a relatively advanced culture, called Neolithic culture. Having, then, great interest in the continuation of the investigations in the cave, I ordered, before coming to London, more extensive researches, and these have been made with very successful results. Dr. Otto Nordenskjéld had previously obtained in 1896 a piece of the same skin, which, it is known, was dis- | NO. 1556, VOL. 60| and s,side view o. tail-sheath, of MWrolania Oweni (greatly reduce i in size) from Pleistocene deposits, Queensland, ‘Australia {originally described as covered by a party of Argentine surveyors during the preliminary studies for the “boundary between Argentina and Chili in the Andean Cordillera, and, recognising also the importance of it, Dr. Erland Nordenskjald went last year to the same spot to look for some more remains. The excavations which he made gave him, so far as I know, some bones, pieces of jaws, teeth, and claws of the same animal, but he did not obtain more remains of the skin.! My assistant, Mr. Hauthal, arrived later at the cave, when Dr. Erland Nordenskjéld had terminated his researches and commenced further exploration. He obtained, not only skulls, jaws, teeth, bones and claws, but also a nearly complete skin of the animal, which shows that it is a Glossothertum, together with bones of Macrauchenia, Equus, and Auchenia, also a great quantity of dung, hay cut by man, ashes, and some bones worked by man. I am not yet sure if the bones of man discovered by Mr. Hauthal were found in the same cave or in one of those in its neighbourhood ; but the pre- sence in the G/ossotherium deposit of bones worked by man is a proof that man and other mammals, whose remains have been discovered in the cave, were contem- porary. I suggest that the skin has been preserved by man for bedding. In the caves inhabited by ancient man in Pata- gonia I have seen cut hay, and probably this also was used for beds. I expect to receive in a few days all these specimens at the same time as those of the A/zo/ania, together with reports on the discoveries, and | think they will arrive in time for me to exhibit these remains at the meeting of the British Association at Dover. The discovery made by Mr. Roth of some advanced Mammalia in the beds that contain dinosaurians, and Mr. Hauthal’s discovery of remains of extinct vertebrates and other mammals in the caves of Southern Patagonia, associated with Macrauchenia, Equus, Auchenia, and man, are proofs of the very recent changes in the physical geography of Patagonia, and afford most I OER eek wile ar a re Fic. 2 —Reproduction of a photograph of the front view of skull, with the lower jaw, of MWyolania. obtained in 1899, from Patagonia, by Mr. Santiago Roth, of the La Plata Museum, Argentine Republic (greatly reduced in size). interesting problems, which can only be solved by a systematic examination of the Argentine country by experienced geologists. In the course of my paper on Patagonia, read before the Royal Geographical Society (May 29), I proposed that this Society, the Royal Society, and the British Museum, with other scientific institutions, should proceed to carry out. these necessary investi- gations. These problems are not extraneous to the ex- plorations which may be carried out by an Antarctic 1 “*E. Nordenskjéld, Neue Untersuchungen jiber Neosylodon listat, Zool. Anzeiger,” vol. xxii. (1899) pp. 335-336. 398 expedition, and I thjak the new discoveries which I now communicate to the Geological Magazine may urge on the despatch of sch expeditions as I propose. If these expeditions be made, how many changes may be pro- duced in actugl and general ideas on the age of the South Amerigan fossiliferous strata, on the disappear- ance of the Jost southern lands, and on the affinities of extinct faunas so distant in time and space as those of South America and Australia ! MR. JOHN CORDEAUX. Y the death of Mr. John Cordeaux, ornithology loses, not only one of its most ardent votaries, but one who had pursued, if he did not strike out for himself, a line very different from that taken by most British lovers of birds. For nearly six-and-thirty years, as shown by a long series of contributions, chiefly to The Zoologist, he applied himself to the study of the phenomena of bird- migration, at first as exhibited on the coasts of Lincoln- shire (in which county he lived) and Yorkshire. This led him in the autumn of 1874 to go to Heligoland for the sake of comparing notes with the now well-known Herr Gatke, whom, it is believed, he was the first British ornithologist to visit; and he soon after wrote for Zhe és (1875, pp. 172-188) a notice of the very wonderful collection formed by that naturalist on that island. In 1879 he joined Mr. Harvie-Brown (who had just communicated a remarkable paper to the Natural History Society of Glasgow) in a successful attempt to procure observations on migrating birds from the keepers of lighthouses and lightships on the coasts of England and Scotland ; and in the following year, when the re- sults of their inquiry were brought before the British Association at the Swansea meeting, he was named secretary of a committee appointed to continue system- atically the scheme which they had shown to be practicable. Of this committee, which (with a slight variation of title) has since been annually reappointed, he has always been the hardworking secretary, and it is not too much to say that nearly all its success is mainly due to him. He not only arranged with the authorities for the distribution of the schedules, instructions, and other information necessary for the observers, but, by his own efforts, raised by subscription a large sum of money to meet the expenses of the inquiry, which proved to be far greater than had originally been anticipated. The time and trouble which all this involved were at first enormous ; and, even to the last, the correspondence which he had to carry on was immense, yet his services were as willingly rendered as though he had been hand- somely paid for them, instead of giving them gratuitously, and the way in which he contrived to interest the men at the lighthouses and lightships in the undertaking was marvellous. The results of this labour, continued with- out intermission for nine years, were partly shown by the admirable ‘ Digest of the Observations,” made by Mr. W. Eagle Clarke, which the.committee was able to include in its report presented to the Association at Liverpool in 1896; and, as has been announced, that gentleman is still occupied in working out further details from the mass of materials that has been collected. Mr. Cordeaux made more than one visit to Heligoland, and is understood to have been instrumental in bringing about the publication of an English translation of Gatke’s celebrated work, though never committing him- self to the adoption of his friend’s views on many points. Indeed, he abstained on principle as much as possible from advocating any theories on the subject of migration, being convinced that much more knowledge had to be acquired from observation before more than a few first principles could be safely accepted. That he was the life and soul of the Migration Committee is beyond all NO. 1556, VOL. 60] NATURE [Avucust 24, 1899 doubt. His happy tact and sanguine temperament over- came all difficulties, though—especially from the financial point of view—they were at times so formidable as to threaten the abandonment of the work ; yet by his care funds were always found to carry it on, eking out the successive and by no means illiberal grants of the British Association. He is said to have been very successful as a lecturer, and he often lectured on some ornithological subject, especially on the migration of birds, in the towns of Yorkshire and other parts of the country. Forty papers are credited to Mr. Cordeaux in the Royal Society’s Catalogue up to 1883, a number which might possibly be doubled now, and in addition to these he was the author of an unassuming but well-written little book, “‘ Birds of the Humber District,” published in 1872, a new edition of which it had been his intention to bring out. He died, after a short illness, at his residence, Great Cotes House, in Lincolnshire, on August 1, in the sixty-ninth year of his age, deeply lamented by all who had been associated with him in the work he so indefatig- ably carried out. NOTES. WE much regret to record that the serious illness of Prof. Rk. W. Bunsen, referred to in last week’s NATURE, has ended fatally. An account of the chief work of this world-renowned chemist appeared nearly twenty years ago in our Series of Science Worthies (vol. xxiii.), and we hope to publish a further appreciation of the deceased investigator next week. Tue funeral of Sir Edward Frankland took place at Reigate on Tuesday. There were present, in addition to the immediate relatives, Sir Frederick Bramwell, Lord Lister, Sir Henry Roscoe, Sir Myles Fenton, Sir Michael Foster, Dr. Ludwig Mond, Dr. Thorpe, and others. The Rey. Prof. Bonney con- ducted the funeral service. Many wreaths adorned the coffin, including one from the Fellows of the Institute of Chemistry and one from the Chemical Society. Major RONALD Ross, the leader of the expedition sent to Sierra Leone by the Liverpool School of Tropical Diseases to investigate the possibility of exterminating the malaria-bearing mosquito, has sent to Liverpool the following cablegram : “*Malarial mosquito found. Ask Government to send at once men.” Major Ross’s observations in India indicated that the malaria parasite is borne by the spotted- winged mosquitoes, and not by the common brindled or grey mosquitoes ; and his mes- sage announces that he has found that malaria on the West Coast of Africa is produced under the same conditions as in India. There is evidence that the malaria-bearing species only breeds in small isolated collections of water which can be easily dissipated, but the expedition has not yet had time to verify this point. THE presence of bubonic plague in Portugal has been officially notified to the Local Government Board. Oporto has been declared to be infected, and the other ports of Portugal are considered suspected. Port sanitary authorities in this country have been instructed in the precautions to be observed to prevent the introduction or spread of the disease here. Ir is announced that Sir Edmund Antrobus is desirous of selling Stonehenge, the famous and mysterious monument on Salisbury Plain. Thinking it right that the nation should have the opportunity of purchasing this great relic of antiquity, the owner has offered it to the Government, with about 1300 acres of surrounding land (subject to certain pasturage and sporting rights), for the sum of 125,000/. % Vi ? AUuGUST 24, 1899| NATURE 399 Pror. GEORGE FORBES, F.R.S., has just visited the Niagara Falls Company, and he describes in the Z¢mes the remarkable success which the Company has attained in the use of the Falls to develop electric energy. An enormous number of factories has been established on the Company’s land, and they use between them no less than 34,590 horse-power. Additions are to be made in October, and two new works, the Atchison Graphite Company and the Lead Reduction Company (Litharge), will be supplied, bringing the total up to 45,190 horse-power contracted for, with an income of over 150,000/. The operating expenses do not exceed 25,000/. per annum. The result indicates, among other matters, the strides which have been taken of late years in electro-chemical and metallurgical processes. With regard to the machinery, the dynamos, which were totally new, not only in size but in their general design, never give the slightest trouble; and the trans- formers, ranging up to 2500 horse-power, have answered their purpose perfectly, even with the low trequency of alternations, which was generally condemned when Prof. Forbes introduced it, but is recognised now by every one at Niagara as contributing largely to the success of the scheme. THE Wellman Polar expedition, which left Tromsé, Norway, on June 26, 1898, returned there from Franz Josef Land on August 17, on the s.s. Cafe//a, which took the party on board at Cape Tegetthof. Mr. Walter Wellman’s intention was to make a rush to the North Pole. According to the Reuter telegram received on Saturday last, an outpost was established as far north as latitude 81°, and two men were left in it to spend the winter, while the main party returned to Cape Tegetthof (lat. 80°). In the middle of February last, in the depth of winter, Mr. Wellman, with three Norwegians and forty-five dogs, started northwards. On reaching the outpost the two men were found, but one had been dead for two months. Pushing northwards the party discovered land north of the Freeden Islands, where Nansen landed in 1895. Inthe middle of March, when all hands were confident of reaching latitude 87° or 88°, if not the Pole itself, Mr. Wellman, while leading the party, fell into a snow-covered crevasse, seriously injuring his leg, and the party was therefore compelled to retreat. Two days later they were roused at midnight by an earthquake, and in a few moments many dogs were crushed and sledges destroyed. Mr. Well- man’s condition became alarming on account o. inflamma- tion, but his companions dragged him on a sledge, making forced marches for nearly 200 miles to the headquarters of the expedition, where they arrived early in April. The Capella arrived at Cape Tegetthof on July 27, and sailed homeward with the party on August 10. Though the ex- pedition has thus ended in failure so far as reaching the North Pole is concerned, it is stated that important scientific observ- ations have been made by Dr. Hoffmann (naturalist), Mr. Harlan (physicist), and Mr. W. B. Baldwin, of the U.S. Weather Bureau, who accompanied the expedition as meteor- ologist and second in command. PrRor. BALBIANT has just diedat Meudon at the age of seventy- five years. The following particulars of his career are given in the Lancet: As Professor of Comparative Embryology at the College of France he was formerly assistant to Claude Bernard at the Museum. Although descended from an Italian family he was born at Havana, and pursued his medical studies at Frankfort-on-the-Main before going to Paris. His reputation was world-wide, and he leaves a considerable number of works, of which the best known deal with the constitution of the egg, the embryonic vesicle, cellular division, the reproductive process in infusoria and aphides, and silkworm disease. He had been many times a laureate of the Institute, but, despite most pressing invitations on all hands, he never presented him- NO. 1556, VOL. 60] self as a candidate at the Institute or Academy of Medicine where he would certainly have been elected. He wished only to be a member of the Society of Biology, of which he was one of the oldest and most industrious members. Besides, for many years past he did not himself lecture, but devoted his time more and more exclusively to the laboratory, leaving his lecture work to his assistant, Dr. Hennegy. Prof. Balbiani was, with Prof. Ranvier, editor of the Archives @ Anatomie Microscopique. THE Z7zmes correspondent at St. Petersburg announces that a new regulation on Russian weights and measures was officially published on August 18. The Russian pound is fixed as the standard of mass and declared to be equal to 409°512 grams, a pail or vedro is to hold 30 pounds of distilled water at 16°°6 C., and a garnietz 8 pounds of water. The unit of length is the arshin, equal to 71°12 centimetres. The metric system is to be optional, and may be used with the Russian in commerce in dealing with contracts, accounts, &c., and after mutual agreement by State and municipal authorities. Private persons are, however, to be under no compulsion to use the metric system when dealing with the above-named aut horities. THE Sczentific American states that the creation of a great national forestry and game preserve in northern Minnesota, embracing 7,000,000 acres around the headwaters of the Mississippi River, with many lakes of rare beauty, well stocked with fish, will be advocated before the U.S. Congress next winter by prominent citizens of Chicago and Minnesota. It is believed that the promoters of the plan will not experience much difficulty in interesting Congress. The game and the virgin forests of the United States are disappearing so rapidly that it is exceedingly important that measures be taken, before it is too late, to save some of the great wooded areas of the continent. UNDER the auspices of the Philadelphia Commercial Museum and the Franklin Institute, a National Export Exposition for the advancement of American manufactures and the extension of the export trade will be held from September 14 to November 30. At the end of last year the U.S. Congress voted 350,000 dollars in support of the exposition, and other funds, amounting to 100,000 dollars, have been provided by the City Councils of Philadelphia and private subscriptions. The exposition grounds comprise a tract of land, fifty-six acres in extent, granted to the Philadelphia museums by the city of Philadelphia, and another tract of six acres secured for the uses of the exposition. Of the five structures comprising the main exhibition buildings three are permanent, but will only be com- pleted at the present time sufficiently for the purposes of the exposition. These three permanent pavilions will have two stories. They will each be 380 feet long and 90 feet wide. The space between them will be covered by temporary build- ings connected with the pavilions, the whole forming a single harmonious edifice. The permanent buildings will eventually become the home of the Philadelphia museums. One of the chief events to take place in connection with the exposition will be the International Industrial and Commercial Congress, which will assemble in Philadelpnia, beginning on October Io, A number of foreign Governments have accepted the invitation to send official envoys, and almost every city of the United States and Canada -with a population over 10,000 will be repre- sented by delegates from their Boards of Trade, Chambers of Commerce, &c. Of special interest to the members of the Franklin Institute will be the ceremonies in commemoration of the seventy-fifth anniversary of the Society, which will be held in one of the exposition buildings. The arrangements for this event contemplate a series of commemorative meetings, “400 IVA TORE beginning Monday efening, October 2, and occupying the entire week. The evenings of the week will be occupied successively by the Sections in the order of seniority, beginning with the Chemical Section. A SERIES of six articles ‘‘ by a Contributor,”’ which appeared in the Banfshire Journal, has been reprinted as a pamphlet entitled ‘Prof. McIntosh on Trawling and Trawling Investi- gations: a criticism and analysis.” It is written with evident detailed knowledge of the work of the Scottish Fishery Board, and of fishery matters in general. Prof. McIntosh’s tables and statistics are carefully analysed—the object being to show that the conclusions in his book, ‘‘ The Resources of the Sea,” are invalidated by the errors which have crept in in the tran- scribing and re-arranging of an enormous mass of figures from the Annual Reports of the Fishery Board. The matter in dis- pute is of such importance that the Fishery Board for Scotland in their next report should definitely and authoritatively state whether or not they accept Prof. McIntosh’s statements as to the results of the trawling experiments off the Scottish coast, and, if not, what grounds they have for arriving at a different conclusion. THE Meteorological Council have published a valuable con- tribution to maritime meteorology, viz. Meteorological Charts of the Southern Ocean between the Cape of Good Hope and New Zealand. The region embraces latitude 30° to 60° S. and longi- tude 10° to 180° E., and the charts show, for each month of the year, the wind direction and force for areas of 3° of latitude by 10° of longitude, the barometrical pressure by isobars, temper- ature of air and sea by isotherms, and ocean currents, in addi- tion to other useful data. The publication will add considerably to the information hitherto available for this part of the ocean, and will therefore be very serviceable to navigators. Intro- ductory remarks draw attention to all the leading results shown by the charts, and to the broad features of the distribution of barometric systems and of air and sea temperature. In the preparation of this work, observations for each four hours have been extracted from about 2450 logs kept for the Meteorological Office or on board H.M. ships, being all that were available between the years 1855 and 1895, and also from numerous logs of private shipping companies. “* Symons’s British Rainfall” (Stanford) for 1898 contains not only the usual statistics and conclusions referring to the distribution of rain over the British Isles last year, but also several articles of general meteorological interest. Thirty-five self-recording rain gauges have been described in previous volumes, and eight more are described in the present report, several of them being illustrated by diagrams showing the principles of construction. In an interesting note Mr. Symons tests the general proposition that the annual rainfall increases with the elevation of the locality above the sea, by applying it to the English lake district. The highest station considered was at Sca Fell Pike (3200 feet), and the lowest Greenside Mine (1000 feet). Group- ing the stations according to altitude in zones differing by 500 feet, no sign of increase or decrease of rainfall with altitude was found—in fact, the lowest group (1000-1499 feet) and the highest (3000 upwards) had identical annual precipitations, viz. 99°3 inches. Moreover, the rainfall at twenty-nine stations having annual amounts of 100 inches or more were arranged according to precipitation, but little evidence was afforded of an increase with elevation, and many of the results point to a con- flicting conclusion. For instance, Seathwaite (altitude 422 feet) has an annual rainfall of 135 inches, while at Seatoller Common (2000 feet) the fall is 126 inches; Dungeon Gill and Ullscarf have both the same fall, though the altitude of the former is 311 feet, while that of the latter is 2100 feet. Mr. Symons con- cludes: ‘* All these cases show that altitude alone has little NO. 1556, VOL. 60] [AuGusT 24, 1899 influence on the amount of rainfall, and that in a mountainous country attention should chiefly be directed to the trend of the hills and valleys in relation to the rain-bearing winds.” Dr. HERGESELL, of Strassburg, has contributed to the Z//:s- trated Aeronautical Magazine (No. 4, Jahrgang 1899) a mathe- matical investigation of the theoretical vertical movements of a free balloon. The subject engaged the attention of Mr. J. Glaisher in the Zxcyclopaedia Britannica, and is of considerable interest for scientific balloon navigation. The first case con- sidered is that of the ascent of an imperfectly inflated balloon, and the formule give the velocity attained in a stratum of air of a definite density, z.e. at a definite altitude, and the time re- quired in reaching this stratum. In the case of a perfectly in- flated balloon, the investigation shows that the maximum height that can be attained depends entirely upon the lifting power, and that it is independent of the velocity of ascent, and of the resistance of the air. Inthe case of the descent of a balloon, it is shown that the velocity of the fall does not continually in- crease, as is often stated, but, on the contrary, decreases, and that there is no danger in allowing the balloon to descend from a great altitude without throwing out ballast, as the velocity of the descent decreases according to the greater height from which the descent is made. M. J. LirpMANN, writing in the /Jowrnal de Physique for August, proposes the adoption of an absolute measure of time based on the Newtonian constant of gravitation. The possi- bility of establishing such a unit depends on the property that the Newtonian constant is independent of the units of length and mass, and is of minus two dimensions in time ; hence, by making the constant of gravitation equal to unity, an absolute unit of time is obtained which is found to be equal to 3862 seconds of mean time approximately. The afore-mentioned property, how- ever, involves the assumption that the unit of mass is of the same dimensions as the unit of volume ; in other words, that density is of no dimensions. Strictly speaking, M. Lippmann’s time unit is of — 4 dimensions in density, and therefore its value depends on the nature of the standard substance chosen as the unit of density. The proposal practically amounts to this: instead of adopting an astronomical unit of density (correspond- ing to the astronomical unit of mass) based on taking the mean solar second as unit of time, we are to adopt an absolute unit of time based on taking water as the unit of density. Tue Alétz det Lincet contains in recent numbers two some- what closely allied papers on thermo-electricity. The first of these is a verification of the principle of thermodynamic equiva- lence for bimetallic conductors, by Signor Paolo Straneo, who concludes not only that thermo-electric phenomena proceed regularly in perfect accordance with theory, but that they can be studied with sufficient exactness by temperature-observations without having recourse to calorimetry. The determination of the Peltier-effect coefficient by the author’s method succeeds even in the case in which previous methods are wanting in accuracy, namely, when the two metals possess a high specific resistance and a feeble Peltier-effect. With the present method, the Joule effect only slightly affects the phenomenon under con- sideration, SIGNOR STRANEO’s method forms the basis of a paper by Signor A. Pochettino on variations of the Peltier-effect in a magnetic field. The value of the Peltier-effect coefficient was observed to vary with the magnetisation. In Signor Pochettino’s experiments, it increased up to a maximum value of 0°008968, corresponding to a field of ninety-eight units, and then de- creased, reaching its normal value (0'008824) in a field of about 345 units, and continuing to decrease as the intensity of the field was further increased. The formula deduced from Houllevigue’s experiments, combined with Thomson’s formula, f ; Aucust 24, 1899| UNCANT, ORLE 401 only represents the phenomenon up to a field of 700 units. Lastly, the variation of the Peltier-effect coefficient is inde- pendent of the direction of magnetisation ; in fact, in suitably- arranged experiments it is found that when the stationary temperature is attained, no changes take place in the thermal conditions of the conductors when the magnetising current is weversed. IN a report received by the Foreign Office, Sir William Garstin has called attention to the need for a scientific examin- ation of the Sudan, with a view to the development of its natural resources. It is pointed out that a very possible source of future wealth to the Sudan lies in the vast forests which line the banks of the Upper Blue Nile and extend, in an easterly direction, to the Abyssinian frontier. In the Bahr-el-Ghazal province also, particularly in the Bongo country, large forest tracts exist. The ebony tree (Dalbergia melanoxylon) is met with south of Karkauj, on the Blue Nile, and again in the vicinity of the Sobat River. On the White Nile, in the Bongo and Rohl districts, the india-rubber creeper (ZLandolphia flortda) is found in great profusion. If the rubber yielded by this ‘creeper be not of quite so good a quality as that obtained from the Assam india-rubber tree (7 vcs e/as¢éca), it is still of suffi- cient value to be counted as an important asset in the future trade of the Sudan. The Assam india-rubber tree should certainly flourish well in most parts of the Sudan, more particu- darly south of Khartoum. Although this tree takes from twenty to thirty years to arrive at a girth sufficient to permit of regular tapping, its yield is so valuable (about 32 per tree per annum) that its introduction into the country is well worth attempting. It is very much to be hoped that a scientific examination of the ‘Sudan forests may ere long be carried out under the super- intendence of an expert. It is certain that much valuable information would be obtained from his report. Very little is known regarding the possibilities of mineral wealth in the Sudan. Until the country is more settled, an investigation of the mountainous regions of Kordofan and Darfur on the west, and of the Abyssinian frontier on the east, would be impossible. Iron ore is found in the Bahr-el-Ghazal province, and also in Darfur ; while gold mines were at one time worked in the mountains south of Fazogl. Could coal be discovered, it would make a great change in the whole question of the Sudan. In a few years’ time it is probable that the Geological Survey Department of Egypt will be able to depute parties to examine the Sudan. For the present, Sir William Garstin thinks nothing can be done. “* VARIATION and Sexual Selection in Man” is the title of a paper by E. Tenney Brewster in the Proceedings of the Boston Society of Natural History (vol. xxix., 1899, p. 45). The author offers evidence to prove that conspicuous dimensions tend tobe more variable than other dimensions. Not only is the face more variable than the head, but the nose should be more variable than the head; the face without the nose should be more variable than the head ; and the nose should be more variable than the rest of the face. The author also suggests that sexual selection has brought it about that parts of the body tend to be more variable in proportion as they are of greater esthetic value. THE Report of the South African Museum for 1898, issued as a Parliamentary Paper, by the Director, Mr. W. L. Sclater, is satisfactory reading. It appears that in all departments the collections are steadily increasing ; while great attention is being paid to the proper exhibition of suitable specimens. In the Geological Department a good collection of the rocks of the Kimberley mining district is already displayed ; and steps are being taken for the formation of a complete collection of the €conomic mineral products of South Africa. This is as it should NO. 1556, VOL. 60] be; and it is equally satisfactory to learn that the Director is fully alive to the necessity of procuring specimens of all the larger mammals before it is too late. The collection of South African antelopes is indeed complete, with the exception of the Gemsbok and Lichi; and specimens of these ought not to be difficult to procure. It may be hoped that, in addition to the mounted specimens, a study series (if possible in duplicate) of skins may likewise be procured. The only subject the Director has to regret is that he has been unable, chiefly from lack of funds, to continue the work of preparing popular descriptive labels for the exhibited specimens. The hope is, however, expressed that the work may be shortly resumed. As an excellent bit of work on the local distribution of a species, attention may be directed to Dr. N. H. Alcock’s history of the Hairy-armed Bat in Ireland, published in the August number of the Zrish Naturalist. In England this Bat is found rather abundantly along the Avon valley in Warwickshire, Worcestershire and Gloucestershire ; it occurs rarely in York- shire, and has been recorded from Cheshire. In Ireland it has been found in most of the north-eastern counties, but nowhere else. We now want to know the reason of this very local dis- tribution ; and until this is ascertained our task is but half done. M. E. Prrarp describes in 7 Anthropologie (x., 1899, p. 281) three crania from Swiss Lake sites. The first from Point, with an index of 91°5, belongs to the Rhetian or Dissentis type, and is remarkably similar to a skull described by M. Verneau from Concise, which that author believed to belong to the Bronze Age ; but M. Pitard asserts that his example is Neolithic. The other two crania were found in the same layer at Concise, and are of the Bronze Age ; their indices are 77°6 and 84:6. THE Vai or Vei are the only negroes who possess a true and indigenous writing. They occupy a territory on the confines of Sierra Leone and Liberia. The alphabet is syllabic, and it is the only syllabic alphabet existing in Africa. The first account of this remarkable language was published by Forbes and Norris in 1849, and Koelle also wrote on it in 1849 and 1854. Since then nothing has been published thereon till the recent study of M. M. Delafosse (2’ Anthropologie, Tome x., 1899, pp. 129, 294). Forbes and Koelle asserted that the alphabet was invented about 1829 or 1839, but Delafosse considers it at least two hundred years old and perhaps older ; it is not even certain that it was invented by the Vais themselves. Forbes was also wrong in stating that this alphabet was no longer in use in 1849; as a matter of fact, it is still increasingly employed. Of the 226 characters in the alphabet, 25 resemble Berber consonants in form, and 20 resemble European letters and numerals ; but these may be purely superficial resemblances, as the sounds do not correspond : the author does not consider that the Vai alphabet has been derived from these sources. Sir J. BURDON-SANDERSON asks us to notify the following errata in his MS. of the abstract of the Croonian Lecture pub- lished in NaTurE of August 10. On p. 344, col. 1, line 5, for “Fig. 1” read “Fig. 2”; col. 1, line 18, for “ Fig. 2 is read “* Fig. 1”; col. 2, line 12 from the bottom, for ‘‘60” read ‘ 40.” Part xv. of Mr. Oswin A. J. Lee’s elaborate work, entitled “¢ Among British Birds in their Nesting Haunts,” has been published by Mr. David Douglas, Edinburgh. The Part con- tains ten beautiful plates, illustrating the nesting places and nests of the whinchat, osprey, storm petrel, yellow bunting, rook pigeon, Manx shearwater. grey wagtail, and red grouse. Herr EUGEN VON CHOLNOKY contributes to the Verhand- dungen der Gesellschaft fiir Erdkunde a short summary of the scientific results of his journeys in China and Manchuria during 1896-98. The most important contributions refer to the geology of the regions visited, and in particular to the positions 402 NALTORE [AucusT 24, 1899 of the great lines of faulting crossing Manchuria, indicated by Richthofen. THE current number of the Zeztschréft der Gesellschaft fiir Erdiunde (vol. xxxiv, No. 2) is entirely devoted to the official reports of the members of the German deep-sea expedition in the Valdivia. Prof. Chun gives a narrative of the expedition and its progress; Dr. Gerhard Schott reports on the ocean- ographical work; and the navigating officer, Herr Walter Sachse, adds an account of the re-discovery of Bouvet Island. A summary of the contents of these reports has already appeared in these columns (p. 114). A NUMBER of students from the Paris Ecole Supérieure d'Electricité visited electrical works and manufactories in Switzerland at the end of last March, this being the second excursion arranged by the authorities of the School. A report upon some of the objects and installations examined was pre- sented to the Société internationale des Electriciens in May, and has just been published as an excerpt from the Az//etzn of the Society, by M. Gauthier- Villars, Paris. THE additions to the Zoological Society’s Gardens during the past week include a Vervet Monkey (Cercopithecus lalandiz) from South Africa, presented by Mr. R. Hilliard; a Brown Capuchin (Cebus fatuellus,?) from Guiana, presented by Colonel Bourchier; a Common Kingfisher (Alcedo zspida), British, presented by Mr. John Porter; an Alexandrine Parra- keet (Palacornis alexandri, 9 ) from India, presented, by Miss J. M. Pott; a Common Boa (Soa constrictor) from South America, presented by Mr. C. W. Lilley; an Alligator (4//z- gator mississippiensis) from Southern North America, presented by Commander H. Woodcock; two Grevy’s Zebras (Zguus grevyt, 8 9) from Southern Abyssinia, a Malayan Bear ( Ursus malayanus) from Malacca, deposited ; three Pink-headed Ducks (Rhodonessa caryophyllacea, 69 9) from India, six Edible Frogs (Rana esculenta), European; twelve Paradise Fish (Macropus viridi-auratus) from China, purchased ; a Japanese Deer (Cervus sika), a Puma (Felis concolor), a Burchell’s Zebra (Zquus burchellé, 2), born in the Gardens. OUR ASTRONOMICAL COLUMN. HoLMEs’ CoMET 1899 d (1892 III.).— Ephemerts for 12h. Greenwich Mean Time. 1899. R.A. Decl. Br. a hemes Brew oh r-2 (rA)-2 August 24 257 44°22 +3817 15°7 o'1888 0°04999 25 58 33°92 38 32 213 265 2059) 22err 38 47 22°9 2 3) ON 837 39 2 204 28 O 53°85 39 17 13°77. O1869 ~=0'05109 29 I 37°31 39 32 27 30 2 19°13 39 46 471 31 25926 +40 I 268 3 During the ensuing week the comet is in a good position for observation by observers having sufficient optical power ; it passes closely to the south of the second magnitude variable star B Persei (Algol). THE PARIS OBSERVATORY.—The annual report of M. Loewy, the director of the Observatory, contains a detailed review of the work accomplished during the past year. Special attention has been devoted to the improvement of meridian observations, chiefly in the attempt to eliminate in- strumental errors by greater precision and stability of the mountings. The small equatoral coudé has been provided with several accessories, and the building covering it so altered that the whole is now adapted for astrophysical observations. The volume of observations made during 1897 will shortly be published in four separate parts, by different authors, who NO. 1556, VOL. 60] will each be responsible for all reductions, descriptions and discussions contained in the part under their names. The fourth part of the Paris Observatory Catalogue (of which the first three parts already published contain all the meridian observations made from 1837-1881) has just been completed. The meridian circles have been in use for fundamental obsery- ations, for a revision of Lalande’s Catalogue, and for work on the variation of latitude. f Coudé Eguatorial.—The large instrument has been chiefly used in obtaining further series of photographs of the moon (scale about 6°5 inches to the lunar diameter) for the large lunar atlas now in progress of publication. During the year 591 plates have been obtained for this purpose. The method of enlargement of the negatives has also been improved. Accompanying the report is a heliogravure of the moon when 20d.59h. old, reproduced the same size as the original plate. For part of the year the photographic objective was replaced by the visual glass, and the instrument then used by M. Hamy for measuring the diameters of small celestial objects by an interference method. The satellites of Jupiter and the planet Vesta have been measured in this way, the diameter of the latter agreeing very closely with the value obtained by Prof. E. E. Barnard. Astrographic Equatorial.—The actual photographic work is now almost completed, all that remains to be done being the replacement of a small number of defective plates. The reduc- tion of the plates for the Catalogue is well in hand, and seven of the Chart plates have been engraved for heliographic repro- duction. “THE BULLETIN ASTRONOMIQUE.”—The August numbercon- tains several interesting and suggestive articles. —M. Flammarion contributes an article on ‘‘ The World of Jupiter,” in which he discusses at length the question of the various rotation periods of the planet, and also an illustrated account of the observation made by M. Antoniadi at Juvisy during the opposition of June 1898.—‘‘ The Rotation of Venus”’ is treated mathematically by Abbé Th. Moreux, based on observations made at Juvisy by M. Antoniadi.—‘‘ Observations of Mars” (illustrated) are contributed by MM. V. Cerulli and J. Chloudoff.—MM. L. Rudaux and Em. Touchet furnish an article on the *« Systematic Observation of Meteors,” giving a suggested form for recording observations systematically, and dealing with the determination of radiants, the physical characters of the swarms, heights of the meteors, and the photographing of them. THE Sun's Heat.—Prof. T. J. J. See contributes a further article dealing with the extension of Helmholtz’s theory of the heat of the sun, in Astr. Mach. (Bd. 150, No. 3586). The method he now pursues is the determination of the potential of a heterogeneous sphere as caused by itself. He finds that the energy developed by the condensation on this assumption is greater than that produced in the condensation of a homogeneou sphere in the ratio of 176,868 to 100,000, , IRON AND STEEL INSTITUTE. THE autumn meeting of the Iron and Steel Institute was held this year at Manchester, on August 15 and 16, under the presidency of Sir William Roberts-Austen, K.C.B,, and was attended by an unusually large number of members. The meetings were held in the Town Hall, the members being welcomed to Manchester in eloquent speeches by the Lord Mayor and by Mr. S. R. Platt, chairman of the Executive Re- ception Committee. In acknowledging the words of welcome, the President referred to the services rendered to metallurgy by Dalton and Joule, and by such great engineers as Fairbairn, Whitworth and Daniel Adamson, Manchester's distinguished sons. The programme was a long and varied one, no less than ten papers being on the list. The first read was by Prof. J. Wiborgh, of Stockholm, whose contribution, which was translated and read by Mr. H. Bauerman,dealt with the use of finely divided iron ore obtained by concentrating pro- cesses. By the introduction of such methods of separation, the power of enriching iron ores has been greatly increased ; but the advantages are qualified by the circumstance that the pro- duct obtained is usually in the form of fine powder, which limits its utility to the smelter. The question of how such material can best be applied is one of importance, and the author shows how the material may be utilised by direct AucusT 24, 1899] NATURE 493 addition to the charges in the blast furnace, by agglomeration previously to charging in the blast furnace, as a refining or softening material in the open-hearth furnace, and for the pro- duction of sponge iron for use in the open-hearth furnace. Mr. H. C. McNeill next read a lengthy paper on some forms of magnetic separators and their application to different ores. The machines described were those invented by Wenstrom, by Delvik-Gréndal, by Heberle, and by Wetherilland the Monarch separator. Results obtained in practice in Sweden were dis- cussed, and numerous illustrations were given. In the discus- sion of these two papers valuable remarks were made by Mr. James Riley, Mr. G. J. Snelus, F.R.S., Sir Lowthian Bell, Mr. Stead and others. A new casting machine for blast furnaces was then described by Mr. R. H. Wainford. It is an ingenious apparatus for casting sandless pig iron in insulated moulds, so as to maintain a good crystalline fracture, equal to that of the pig iron made in sand beds, at a reduced cost of production. The advantages and disadvantages of this apparatus were discussed by Mr. FE. Windsor-Richards, Mr. W. Hawdon, Mr. Cooper and Sir Lowthian Bell. Mr. Syed Ali Bilgrami, Secretary to H.H. the Nizam’s Government Public Works Department, Railways and Mines, then read a paper on the iron industry in Hyderabad. He described the geological structure of the Nizam’s-territory, and the various iron ore deposits met with. Some interesting facts were brought forward by Major R. H. Mahon, of Cossipore, relating to the possibility of manufacturing at a profit iron and steel in India. In the absence of the author this paper was read by the Secretary, Mr. Bennett H. Brough. An interesting discussion followed, in which Mr. Bauerman and Mr. R. Price-Williams took part. The meeting was then ad- journed until Wednesday, when a paper by Mr. C. H. Ridsdale was read. The microscopic examination of steel is a subject on which a good deal has been written during the last few years. Most of the papers hitherto published have dealt with the matter from a purely scientific point of view. The aim of the exhaustive paper contributed by Mr. C. H. Ridsdale was to show the practical value of the microscope to the steel maker and user at the present day. The time has now arrived, he points out, when it should be recognised that composition only indicates such well-defined effects as are generally understood without certain narrow limits of treatment, which are termed ‘‘ normal.” Outside these limits the effect of the treatment far outweighs that of the composition. In the discussion of this paper the President, Mr. Greiner, Mr. Harbord and Mr. Stead took art. Mr. J. W. Miller contributed a paper on pig iron fractures and their value in foundry practice. He gave instances of the loss sustained by the manufacture of pig iron owing to the present method of grading pig iron by fracture. The present position of the solution theory of carburised iron was discussed by Dr. A. Stansfield. The conclusions he has arrived at with respect to the atomic complexity in carbon are as follows :— The carbon in molten iron is ina state of simple solution ; the molecule of carbon must then contain one or two atoms, and is probably monatomic. The solidified iron is in the y state and contains free carbon in solution. The molecular weight of this carbon has not been discussed, but it is probably the same as that in the molten iron. The carbon in solid solution combines with iron, on cooling, to form a carbide, which is probably expressed by the formula 2(Fe;C). When, on further cooling, this carbide falls out of solution as cementite, its formula may become more complicated ; the solution theory affords no information on this point ; but Sir W. Roberts-Austen stated in his presidential address that the nature of the products of its solution in acids led to the conclusion that the molecule may contain six atoms of carbon, and is at least as complex as would be indicated by the formula 6(Fe,C). There appears to be a belief that the solution theory is in a sense opposed to, and has gone far to supplant, the older allotropic theory ; but this paper will, it is hoped, effectually dissipate such an error, as it shows how entirely the solution theory of the relations of carbon and iron involves the allotropic changes with which the distinguished name of Osmond is so inseparably connected. In the discussion of this paper Mr. Snelus, Mr. Hadfield and Mr. Stead took part. Mr. A. Sauveur, of Boston, contributed a paper on the changes of structure brought about in steel by thermal and mechanical NO. 1556, VOL. 60] treatment. Ife showed that as the smaller the grains of the metal the more ductile and tough it will be, as the finest possible structure results from heating to Brinell’s point W, the temperature at which the passage of cement carbon into harden- ing carbon during the heating of steel takes place, namely, 655° to 730° C., it is evident that every finished piece of unhardened steel should as a last treatment be heated to that temperature. Prof. E. D. Campbell, of Ann Arbor, Michigan, con- tributed a paper on the constitution of steel. The general method employed for studying the products of steel was to dissolve the steel in hydrochloric acid, pass the gas evolved through bromine in order to convert unsaturated hydrocarbons of the general formula C,H,,, into their di-brom derivatives C,,H,,,Br, ; the gas passing through the bromine being measured, and the carbon existing as gaseous paraffins being determined by explosion and absorption of the carbon dioxide produced. The di-brom derivatives, after proper purification, drying, and weighing, were analysed and fractionally distilled for the purpose of qualitatively identifying the various constituents ; although the fractional distillation of the di-brom derivatives had shown the presence of ethylene, propylene, butylene, pentylene, and hexylene di-bromides, and dibutylene tetra- bromide, later investigations had shown that this last product was the result of the polymerisation under the influence of heat during distillation of butylene di-bromide, and was not present to any considerable extent, at least in the original derivatives. Although the di-brom derivatives from ethylene dibromide (C,H,Br,) to hexylene dibromide (C,H,.Br,) had been detected qualitatively, the separation of the various derivatives by frac- tional distillation zz vacuo was not sufficiently sharp to give accurate quantitative results in regard to the amount of each constituent present. From the percentage of bromine in the di-brom derivatives the average number of carbon atoms in the molecule was calculated, the results of the examination of a few samples of steel by the above method being shown in the following table :-— | 3 bg | 83 Bs 63 /s,4|/58.|58 | Seu ease | Mee ;a2 ‘946 S35 ood (Saad N | Heat aS Bes | | tote ;o5 | oa3 Bans ame. | treatment. 8 8 82$ 4 g & ga} o Bs 23 os $8 | 588) Seca) 53 | FERS sees Ad |A DU] Sg 58 Aso /eokU 2 a [Vp] 5 os F |Annealed | 0°55] 37°1 | 33°6| 29°3 | 72°56) 4°32 Hardened FE and 0°55| 25°0 75°65 | 3°67 tempered \ C Annealed 1°14) 43°4 | 37°9 | 18:7 | 73°85 | 4°05 C |Hardened| 1°14) 29°0 | 48°6 | 22°4 | 77°61 | 3°31 D_sAnnealed 1:28] 31:0 | 44°3 | 24°7 | 77°80| 3°26 ‘Pure Car- |bide from] > 6°64) 35°3 | 25°2 | 39°5 4°41 Danneal’d The number of carbon atoms in the carbon molecule of the derivatives from the pure carbide, given in the above table, was obtained from the analysis of the gas by dividing the volume of carbon dioxide, produced from the explosion of the olefines, by the volume of the olefines exploded. The hypothesis suggested by the author made the fundamental assumption that carbon formed with iron a series of compounds which might properly be termed “ferrocarbons,” on account of their similarity in structure to hydrocarbons. This series of ferrocarbons had the empirical formula (CFe,),, 3 or, C,Fes,, and should be con- sidered as being derived from the hydrocarbons of the olefine series with the general formula C,,H,, by the replacement of the H, by the bivalent group Fes. These ferrocarbons, dissolved in hydrochloric acid, yield as their primary products of solution the corresponding olefines and hydrogen. During the meeting excursions were arranged to the loco- motive works at Horwich, to the Simon-Carvés coke ovens near Barnsley, to the Manchester Ship Canal, to the ironworks of Platt Brothers, Ltd., at Oldham, to the boiler works of Galloways, Ltd., and to the steel works at Crewe; and hospitality was lavishly dispensed to the members by the Duke of Devonshire at Chatsworth, by the Lord Mayor of Manchester, and by the Mayor of Salford. 404 NATURE [AucusT 24, 1899 MAGNETO-OPTIC ROTATION AND ITS EXPLANATION BY A GYROSTATIC SYSTEM} II. I MUST now endeavour to give some slight account of the theories that have been put forward in explanation of magneto-optic rotation. There is an essential distinction between it and what is sometimes called the natural rotation, the plane of polarised light produced by substances, such as solutions of sugar, tartaric acid, quartz, &c., some of which rotate the plane to the right, some to the left. When light is sent once along a column of any of those substances without any magnetic field, its plane of rotation is rotated just as it is in heavy glass or bisul- phide of carbon in a magnetic field. But if the ray, after pass- ing through the column of sugar or quartz, is received on a silvered reflector and sent back again through the column to the starting point, its plane of polarisation is found to be in the same direction as at first. Quite the contrary happens when the rotation is due to the action of a magnetic field. Then the rotation is found to be doubled by the forward and backward passage, and it can be increased to any required degree by send- ing the ray backward and forward through the substance, as shown in this other diagram (Fig. 8). Thus the rotations in the two cases are essentially different, and must be brought about by different causes. In fact, as was first, I believe, shown by Lord Kelvin, the annulment of the turning in quartz, and the reinforcement of the turning in a magnetic field, produced by sending the ray back again after reflection at the surface of an optically denser medium, points to a peculiarity of structure of the medium as the cause of the turning of the plane of polarisation in sugar solutions and quartz, and to the existence of rotation in the medium as the cause of the turning in a magnetic field. Think of an elastic solid, highly incompressible and endowed with great elasticity of shape and of the same quality in different directions—a stiff jelly may be taken as an example to fix the ideas, Now let one portion of the jelly have bored into it a very large number of extremely small corkscrew-shaped cavities, having their axes all turned in the same direction. Let another portion have imbedded in it a very large number of extremely small rotating bodies, spinning-tops or gyrostats in fact, and let these be uniformly distributed through the substance, and have their axes all turned in the same direction. Both portions would transmit a plane-polarised wave of trans- verse vibration travelling in the direction of the axes of the cavities or of the tops with rotation of the plane of polarisation ; but in the former case the wave, if reflected and made to travel back, would have the original plane of polarisation re- stored ; in the latter the turning would be doubled by the backward passage. To understand this it is necessary to enter a little in detail into the analysis of the nature of plane-polarised light. As I have already said, the elastic solid theory may not express the facts of light propagation, but only a certain correspondence with the facts. But its use puts this matter in a very clear way. Ina ray of plane polarised light each portion of the ether has a motion of vibration in a line at right angles to the ray, and the direction of this line is the same for each moving particle. The lines of motion and the relative positions of the particles in a wave are shown in the first diagram (Fig. 1 p. 379). As the motion is kept up at the place of excitation, it is propagated out by the elastic resistance of the medium to displacement, and the configuration of particles travels outwards with the speed of light, traversing a wave-length (represented in the diagram by the distance between two particles of the row in the same phase of motion) in the period of complete to-and-fro motion of a particle in its rectilineal path. Now, a to-and-fro motion such as this can be conceived as made up of two opposite uniform and equal circular motions. Think of two distinct particles moving in the two equal circles als Fig, 8. 1 A discourse delivered at the Royal Institution by Prof. Andrew Gray, F.R.S. (Continued from p. 381.) NO. 1556, VOL. 60] AB in this diagram (Fig. 9), with equal uniform speeds in opposite directions. Let each particle be at the top of its circle at the same instant; then at any other instant they will be in similar positions, but one on the right, the other on the left of the vertical diameter of the circle. Thus at that instant each particle is moving downward or upward at the same speed, while with whatever speed one is moving to the left, the other is moving with precisely that speed towards the right. Imagine now these two motions to be united in a single particle. The vertical motions will be added together, the right and left motions will cancel one another, and the particle will have a motion of vibration in the vertical direction of range equal to twice the — — diameter of the circles, and in the period of the circular motions. The rate of increase of velocity : of the particle at each instant is the : resultant obtained by properly add- ing together the accelerations of the Fic. 9. particles in the circular motions, and therefore the force which must act on the particle to cause it to describe the vibratory motion just described is the resultant of the forces required to give to the two particles the circular motions which have just been considered. Now, what we have done for any one particle may be con- ceived of as done for all the particles in a wave. To understand the nature of a wave in this scheme, we must think of a series of particles originally in a straight line in the direction of pro- pagation of the ray, as displaced to positions on a helix surround- ing that direction. Fig. A of this diagram (Fig. 10), regarded from the lower end, and the black spots on the model before | you, show a left-handed helical arrangement. Let these particles. be projected with equal speeds in the circular paths represented by the circle at the bottom of Fig. A. On this circle are seen >. (\-» - w ~~ a me ( sy - — ‘S AL0QGE é inne: ~. () ( ie 0 the apparent positions of different particles in the helical arrange- ment when it is viewed by an eye looking upwards along its axis. This motion is shown by that of the black spots on the surface of the model (Fig. 11), when I set it into rotation about its axis. Let the particles be constrained to continue in motion exactly in this manner. As the model shows, the helical ar- rangement of the particles is displaced along the cylinder. This is the mode of propagation of a cevczdarly polarised wave, which is made up of helical arrangements of particles which were formerly in straight lines parallel to the axis. The direction of propagation of the wave is clearly from the AucustT 24, 1899] IMA TU RL 405 bottom of the diagram to the top, and from the end of the model towards your left to the other, when the particles have a right-handed motion, and is in the contrary direction when the direction of rotation is reversed. For a right-handed helical arrangement the direction of propagation for the same direction of motion of the particles is the opposite of that just specified. The direction of propagation remains, therefore, the same when the direction of motion and the helical arrangement of the particles are both reversed. All this can be made out from the Fig. B shows part of a right-handed arrangement of diagram. polarisation produced in the forward passage is undone in the backward. It is easy to see that the same thing will take place if the reflection is at the surface of an optically rarer medium, so that the direction of motion of the particles is the same in the | reflected as in the direct wave. The helical arrangements, | however, are reversed by the reflection, and hence the wave | which travelled the more quickly forward travels the more slowly back, and again the turning of the plane of polarisation is annulled by the backward passage. Thus Lord Kelvin’s hypothesis of difference of structure com- pletely explains the phenomena. | | | | | We fass now to the other case, that of magneto-oplic rotation. Let us suppose, to fix the ideas, that the right-handed Fic. 11. particles corresponding to the opposite arrangement of Fig. A ; | and if the particles have the motions shown at the bottom of the diagram the propagation will be for both in the same direction, from the bottom to the top. In Fig. 10 we suppose the periods equal and also the wave- lengths, the distance along the axis from particle 1 to particle 9. The combination of the circular motions A and B gives recti- linear motion; the combination of the wave motions of Figs. A and B gives a plane polarised wave the plane of polarisation of which does not change in position. If, however, while the periods were equal, the wave-lengths were unequal as shown in this other diagram (Fig. 12), the plane of polarisation would rotate, as shown by the lines drawn across the paths in the figure on the right, for the circular motions of particles in the longer wave would gain on those in the shorter. A little consideration will show that the direction of the re- sultant rectilinear motion will, in consequence of the unequal speeds of propagation, turn round as the wave advances, and will do so in the direction of motion of the particles in the more quickly travelling wave, generating the screw surface shown in the model I have already exhibited. We must now consider the forces. The particles moving in the circular paths have accelerations towards the centres of these paths, and forces must be applied to them to produce these accelerations. These forces are applied in the present theory by the action of the medium, and it is the reactions of the par- ticles on the medium that are properly called the centrifugal forces of the particles. The requisite centreward forces then are supplied by the state of strain into which the medium is thrown by the displacement of parts of it, which form in the undisturbed position a series of straight arrays in the direction of propa- gation, into these helical arrangements round that direction. The greater these elastic forces the greater the velocity of | propagation of the wave. In an elastic medium these forces depend on the amount of the relative displacements of the particles, and will be greater for displacements in the right-hand helical arrangement than for displacements in the opposite direction if the medium has a greater rigidity for right-handed distortion than for left, and the right-handed wave of distortion will be transmitted with greater speed, and wice verst. This is the case of solutions of sugar and tartaric acid, quartz, &c., for which a helical structure has been supposed to exist in the medium. Taking this case refer to Figs. A and B of our large diagram (Fig. 10), and let the right-handed wave travel the faster. Let the waves travel up, be reflected at the upper ends, as at the surface of a denser medium, and then travel down again. The reflected waves are those shown in Figs. A’, B’ of the diagram. By the reflection, the helical arrangement will be unaltered. But the plane of polarisation, as we have seen, turns round in space in the direction of the motion of the particles in the more quickly moving wave ; it therefore turns round in the direction of the hands of a watch as the wave moves in the upward direc- tion in the diagram, and in the opposite direction when the | wave is travelling back. Thus the rotation of the plane of NO. 1556, VOL. 60] circular ray travels faster than the other, and that whether direct or reversed. Here, as in the other case, the elastic reaction of the medium on the displaced particles depends only on the distortion, and if there be no structural peculiarity in the medium there must be the same reaction in the particles in both the circular waves which combine to make up the plane- polarised one. Thus the actions on the particles being the same for both waves, and the velocities of propagation being different, the motions concerned in the light propagation cannot be the same. There must in fact be a motion already existing in the medium which, compounded with the motions concerned in light propagation, give two motions which give equal reactions in the medium against the equal elastic forces, applied to the particles in the case of equal helical displacements. Thus Lord Kelvin supposes that in the medium in the mag- | netic field there exists a motion capable of being compounded BEACBRL Pp 6O0u on 6, 4 7 3 3 fl Fic. 12. with the luminiferous motion of either circularly polarised beam. The latter is thus only a component of the whole motion. In the very important paper in which he has set forth his theory Lord Kelvin expresses his strong conviction that his dynamical explanation is the only possible one. _ If this view be correct, Faraday’s magneto-optic discovery affords a demon- stration of the reality of Ampére’s theory of the ultimate nature of magnetism. For we have only to consider the particles of a magnetised body as electrons or groups of charges of electricity, ultimate as to smallness, rotating about axes on the whole in 406 alignment along the direction of the magnetic force, and with a preponderance of one of the two directions of rotation over the other. Each rotating molecule is an infinitesimal electro- magnet, of which the current distribution is furnished by the system of convection currents constituted by the moving charges. The subject of magneto-optic rotation has also been con- sidered by Larmor, and two types of theory of these effects have been indicated by him in his report on the ‘‘ Action of Magnetism on Light.” One is represented by Lord Kelvin’s theory, which is illustrated by Maxwell’s chapter on molecular vortices in his ‘‘ Electricity and Magnetism.” FitzGerald’s paper ‘‘On the Electromagnetic Theory of the Reflection and Refraction of Light,” in the P/zlosophical Transactions for 1880, is related to Maxwell’s theory, and explains the rotation produced by reflection from the pole of a magnet by means of the addition of a term to the energy of the system. The other theory is also a purely electromagnetic one, and supposes that the effects are due to a kind of zolotropy of the medium set up by the magnetisation, and so attributes them to a change of structure which introduces rotational terms into the equations connecting e/ectréc displacements and electric forces. This latter theory therefore regards the magneto-optic rotation as only a secondary effect of the magnetisation, which is not sup- posed to exert any direct dynamical influence on the transmission of the light-waves. It is not possible here to enter into the subject of these theories, but I should like to direct attention to a paper by Mr. J. G. Leathem, published in the Phzlosophical Trans- acttons, in which the type of theory just referred to has been worked out and compared in its results with the experiments of Sissingh and Zeeman in refiection. These investigators made measurements of the phase and amplitude of the magneto- optic component of the reflected light for various angles of incidence. For both these quantities the theoretical results of Leathem agree very well with the observed values. Returning now to the gyrostatic medium, between which and the electromagnetic theory, it is to be remembered, there is a correspondence, we may inquire in what way the gyrostats, when moved by the vibrations of the medium, react upon it, and so affect the velocity of propagation. The motion of a gyrostat is often regarded as mysterious, and it can hardly be fully explained except by mathematical investigation. But the general nature of its action may be made out without much difficulty, First of all, a gyrostat consists of a massive fly-wheel running on bearings attached to a case which more or less completely encloses the wheel. The mass of the wheel consists in the main of a massive rim, which renders as great as possible what is called the moment of momentum of the wheel when rotating about its axis. The diagram (Fig. 13) represents a partial sec- tion of the case and fly- wheel of a _ gyrostat, showing the arrangement of fly-wheels and bear- ings. Now let the fly-wheel of such a gyrostat be rapidly rotated, and the gyrostat be hung up as shown in this other dia- gram (Fig. 14), with the plane of the fly-wheel vertical, and a weight attached to one extremity of the axis. The gyro- stat is not tilted over, but begins to turn round the cord by which it is suspended with a slow angular motion which is in the direction of the horizontal arrow, if the direction of rota- tion is that of the circular arrow shown on the case. The same thing is shown by the experiment I now make. I spin this gyrostat and hang it with the axis of rotation horizontal by passing a loop of cord round one end of the axis so that the weight of the gyrostat itself forms the weight tending to tilt it over about the point of suspension. The axis of rotation here again remains nearly horizontal, but turns slowly round in a horizontal plane as before. NO. 1556, VOL. 60] Fic. 13. NATURE AUGUST 24, 1899 The explanation in general terms is this. The weight gives a couple tending to turn the gyrostat about a horizontal axis at right angles to that of rotation. This couple in any short interval of time produces moment of momentum about the axis specified, the amount of which is the moment of the couple multiplied by the time, and may be represented in direction and magnitude by the line op. This must be compounded with the moment of momentum OA already existing about the axis of rotation, and gives for the resultant moment of mo- mentum the line oC, which is the direction of the axis of rotation after the lapse of the short interval of time. The axis of rotation thus turns slowly round in the horizontal plane, and the more slowly the more rapidly the fly-wheel rotates. The gyrostat in fact must have this precessional motion, as it is sometimes called, in order that the moment of momentum of the gyrostat about a vertical axis may remain zero. Thatit must remain zero follows from the fact that there is no couple in a horizontal plane acting on the gyrostat. Thus any couple tending to change the direction of the axis in any plane produces a turning in a perpendicular plane. For example, if a horizontal couple, that is about a vertical axis, were applied to the axis of the gyrostat in the last figure it would turn about a horizontal axis, that is, would tilt over. Again, consider a massive fly- wheel mounted on board ship on a horizontal axis in the di- rection across the ship. The rolling of the ship changes the direction of the axis, and pro- duces a couple applied by the fly-wheel to the bearings and an equal and opposite couple applied by the bearings to the fly-wheel. This couple is in the plane of the deck, and is re- versed with the direction of rolling, and has its greatest value when the rate of turning of the shipis greatest. Thus the force on one bearing is towards the bow of the ship, the force on the other towards the stern, during a roll from one side to the other ; and these forces are reversed during the roll back again. This is the gyrostatic couple exerted on its bearings by the armature of a dynamo on shipboard. In the same way, when a gyrostat is embedded in a medium and the medium is moving so as to change the direction of the axis of rotation, a couple acting on the medium in a plane at right angles to the plane of the direction of motion is brought into play. To fix the ideas, think of a row of small embedded gyrostats along this table with their axes in the direction of the row, and their fly-wheels all rotating in the same direction. Now let a wave of transverse displacement of the medium in the vertical direction pass along the medium in the direction of the chain. The vibratory motion of each part of the medium will turn the gyrostatic axis fromthe horizontal, and thereby in- troduce horizontal reactions on the medium. Again, a wave of horizontal vibratory motion will introduce vertical reactions in the medium from the gyrostats. Now, a wave of circular vibrations, like those we have already considered, passing through the medium in the direction of the chain, could be resolved into two waves of rectilinear vibration, one in which the vibration is horizontal, and another in which the vibration is vertical, giving respectively vertical and hori- zontal reactions in the medium. The magnetisation of the medium is regarded as due to the distribution throughout it of a multitude of rotating molecules, so small that the medium, notwithstanding their presence, seems of uniform quality. The molecules have, on the whole, an alignment of their axes in the direction of magnetisation. These reactions on the medium when worked out give terms in the equations of wave propa- gation of the proper kind to represent magneto-optic rotation. It is worthy of mention that the addition of such terms tothe equation was made by McCullagh, the well-known Irish mathe- matician, who, however, was unable to account for them by any Fic. 14 a AucusT 24, 1899] NATURE 407 physical theory, The necessary physical theory may be regarded as afforded by the mechanism which thus forms an essential part of Lord Kelvin’s mode of accounting for magneto-optic effects. Lord Kelvin, in his Baltimore Lectures, has suggested for magneto-optic rotation a form of gyrostatic molecule consisting, as shown in the figure, of a spherical sheath enclosing two equal gyrostats. These are connected with each other and with the case by ball-and-socket joints at the extremities of their axes, as shown in Fig. 15. If the spherical case were turned round any axis through the centre no disalignment of the gyrostats con- tuined in it would take place, and it would act just like a simple gyrostat. If, however, the case were to undergo translation in any direction except along the axis, the gyrostats would lag behind, and the two-link chain which they form would bend at the centre. This bending would be resisted by the quasi-rigidity of the chain produced by the rota- tion, and the gyrostats would react on the sheath at the joints with forces as before at right angles to the plane in which the change of direc- tion of the axis takes place. The general result is, that if the centre of this molecule be carried with uniform velocity ina circle in a plane at right angles to the line of axes, the force required for the acceleration towards the centre, and which is applied to it Fic. 15. by the medium, is greater or less according as-the direction in | which the molecule is carried round is with or against the | direction of rotation of the gyrostats. That is, the effect of the rotation is to virtually increase the inertia of the molecule in the one case and diminish it in the other. These molecules embedded in the medium are supposed to be exceedingly small, and to be so distributed that the medium may, in the consideration of light propagation, be regarded as of uniform quality. Lord Kelvin’s last form of molecule, it may be pointed out, if the surface of its sheath adheres to the medium, will have efficiency as an ord- inary single gyrostc: es regards rotations of the molecule, and efficiency likewise as regards translational motion of the centre of the molecule. The former efficiency can be made as small as may be desired by making the molecule sufficiently small ; the latter may be main- tained at the same value under certain conditions, however small the molecule * be made. The lately discovered effect of a magnetic field in giving one period of circular oscillation of a particle or another according as the particle is revolving in one direction or the other about the direction of the magnetic force, is connected with magneto- optic rotation. There is a connection between velocity of propagation and frequency of vibration, which is exemplified by the phenomena of dispersion. In the Faraday effect, the two modes of vibration, if of the same period, have different velocities of vibration, consequently these two modes of vibration must have different frequencies for the same velocity of propagation. The vibrations of the molecules of a gas in which the Zeeman effect is produced by a magnetic field may be represented by the motion of a pendulum the bob of which contains a rapidly 1G. 1€.—Path of the Bob of a Gyrostatic Pen- dulum. As the pendulum moves, it passes :rom cne ray to another on the opposite side, and the direction of motion at each swing alters through the angle between two rays. The central parts of the rays are left out. The marking point does not pass exactly through the centre. rotating gyrostat with its axis in the direction of the supporting | NO. 1556, VOL. 60] wire of the pendulum. The period of revolution of the bob when moving asa conical pendulum is greater or less than the period when the gyrostat is not spinning according as the direction of revolution is against or with the direction of rotation. The bob when deflected and let go moves in a path which constantly changes its direction, so that if a point attached to the bob writes the path on a piece of paper, a star-shaped figure is obtained. I cause the gyrostatic pendulum here suspended to draw its path by a stream of white sand on the black board placed below it, and you see the result. I must here leave the subject, and may venture to express the hope that on some other occasion some one more specially acquainted with the electromagnetic aspects of the phenomenon may be induced to place the latest results of that theory before you. UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Mr. JAMES Brown THomson, of Kinning Park, Glasgow, who died ten months ago, left $0,000/. to Glasgow institutions —mostly educational and benevolent. The Glasgow University will receive 10,000/. THE recent discussion in NATURE on ‘‘The Duties of Provincial Professors” forms the subject of a short critique in the August number of the Aducational Review. While fully endorsing the general views expressed in our columns, the Review remarks: ‘‘ There is only one flaw in the indictment —the insinuation, namely, that university professors should take no part in the social life and physical activities, the general discipline, the corporate existence of the university or university college.” But where does this flaw exist ? No such insinuation is made in the article in NATURE. THE Department of Science and Art has issued the following list of successful candidates for Royal Exhibitions, National Scholarships, and Free Studentships (Science) awarded this year :—Royal Exhibitions: William M. Selvey, Edward C. Moyle, Archibald D. Alexander, Charles W. Price, George F. A. Cowley, Edgar Sutcliffe, Sydney A. Edmonds. National Scholarships for Mechanics: Francis P. Johns, George F. Turner, Walter A. Scoble, Arthur J. Spencer, William H. Adams. Free Studentships for Mechanics: R. Borlase Matthews, William H. Outfin. National Scholarships for Physics: William R. Daniel, William J. Lyons, James Lord, William M. Varley, Wilfred H. Clarke. Free Studentships for Physics: John H. Shaxby, Gerald Henniker. National Scholarships for Chemistry: William D. Rogers, John H. Crabtree, Howard E. Goodson, Arthur H. Higgins, Montague W. Stevens. Free Studentships for Chemistry: John R. Horsley, Arthur C. Nicholson. National Scholarships for Biology : Eric Drabble, Louis E. Robinson, Ernest A. Wraight, Reginald F. G. Bayley, Harold B. Fantham. National Scholarships for Geology: William H. Goodchild, Thomas Thornton. THE iollowing list of candidates, successtul in this year’s com- petition for the Whitworth Scholarships and Exhibitions, has been received from the Department of Science and Art :— Schoiarships, tenable for three years, 125/. a year each: Alec W. Quennell, London ; Hanson Topham, Great Horton, Bradford ; William V. Shearer, Langside, Glasgow; George Wall, Oldham. Exhibitions, tenable for one year, value 50/. each: Arthur J. Spencer, Portsmouth; George F. Turner, Sheffield ; Harold P. Philpot, London; William H. Adams, Devonport; Edward C. Moyle, Devonport ; Walter A. Scoble, E. Stonehouse, Devon ; Archibald D. Alexander, Portsmouth ; Sydney A. Edmonds, Devonport; George F. A. Cowley, Portsmouth ; Albert Wilson, Leeds; Edwin J. Britton, Ports- mouth ; Harry Duncan, Plumstead; Samuel C. Rhodes, Mor- ley, Leeds; Harry M. Andrew, Manchester; Alexander P. Traill, North Shields; Leonard Bairstow, Halifax ; William T. S. Butlin, Bristol; Albert E. Dodridge, Devonport ; James Lowe, Alloa; William J. Rodd, Plumstead ; Francis C. Rendle, | Plymouth ; Thomas E. Heywood, Cardiff; James Paul, Wool- wich; Charles P. Raitt, Portsmouth; Charles H. Booth, Bolton ; Edward Howarth, Oldham; Percy Down, London ; Marshall H. Straw, Sneinton, Nottingham; R. Borlase Matthews, Swansea ; Samuel Crossley, Oldham. 408 NAGORE [AuGuST 24, 1899 SOCIETIES AND ACADEMIES, EDINBURGH. Royal Society, July 17.—The Hon. John Abercromby in the chair.—The Keith prize for the period 1895-97 was awarded to Dr. Thomas Muir, for his valuable mathematical papers pub- lished in the 7yansactéons and Proceedings. The Makdougall- Brisbane prize for the period 1896-98 was awarded to Dr. William Peddie, for his experimental researches on the torsion of wires, his discussion of a unique case of colour-blindness, and other investigations in physical science. The Neill prize for 1895-98 was awarded to Prof. Cossar Ewart, for his important investigations bearing on the theory of heredity.— A paper by Lord Kelvin, on magnetism and molecular rotation, was com- municated, the main conclusion of which was that a gyrostatic molecule could not in a strong magnetic field give the Zeeman effect. Only a broadening of the lines, not a splitting, could occur. This agreed with Larmor’s statement ; and the prob- ability was that Lorentz’s theory was essentially true.-——-Sir John Murray and Mr. F. P. Pullar read a first instalment of their account of a bathymetrical survey of the Scottish fresh-water lochs. These could be divided into two great classes, the deep and the shallow. The shallow lochs varied considerably in temperature throughout the year—a fact which had an important bearing on the forms of animal life frequenting these lochs. The lochs discussed were Lochs Katrine, Arklet, Achray, Vennacher, Drunkie, Voil, Doine, and Lubnaig. 2422 soundings had been taken. The greatest depth observed in Loch Katrine was 495 feet ; and about one square mile of the bottom of this loch was below sea level. The portable sounding machine used had been designed by Mr. Pullar.—Dr. Hepburn exhibited a new osteo- metric board, the idea of which was to keep the vertical sliding piece always perfectly parallel to itself. This was effected by means of two brass rods parallel to each other and parallel to the graduated board. These passed through holes in the vertical sliding piece. By this simple device all irregularities in suc- cessive measurements of the same bone were quite done away with. PARIS. Academy of Sciences, August 14 —M. Maurice Lévy in the chair.—Researches on the metallic derivatives of acetylene, by MM. Berthelot and Delépine. Thermochemical experi- ments on the compounds of acetylene with silver, silver nitrate, silver sulphate; silver chloride and iodide. Dry silver acetylide, Ag,C,, detonates when heated in a vacuum with production of a reddish flame. The authors discuss the nature of this ex- plosion, since the products being solids, silver and carbon, no flame would be expected. The conclusion is arrived at that the temperature of the reaction is sufficient to volatilise the carbon, and that the flame is gaseous carbon at a very high temperature approaching 4000" C.—Reaction of argon and nitrogen with mercury alkyls, by M. Berthelot. Mercury methyl, Hg(CHy)., submitted in an atmosphere of argon to the action of the silent electric discharge, forms no compound with argon, although when the argon is replaced by nitrogen the latter is readily absorbed. With mercury phenyl, Hg(C,gH5)o, a slight absorption of argon is noticeable, amounting to about 5 per cent. in twenty- three hours. —Observ- ations of Tempel’s Comet (1873 II.), made at the Observatory of Paris (with the 30°5 centimetre equatorial), by M. G. Fayet. The observations were carried out on the nights of July 31, August 9 and 10. The comet was at its brightest on July 31, although very low down on the horizon.—Observations of the Perseids of 1899, by Mlle. D. Klumpke. These observations were made under very favourable conditions of sky between August 9 and 13.—On the shower of shooting stars (Perseids) at Lyons, and a remarkable meteor, by M. Ch. André. The August showers of shooting stars were relatively small in number at Lyons. On the evening of the 11th a remarkable meteor was seen starting at about 10°43 p.m. from the constellation of Hercules. It was bluish-white at first, changing abruptly in colour to an orange-red. It was under observation for four seconds.—On the correspondence between right lines and spheres, by M. O. E. Lovett.—On the blacl. pottery earths, by M. H. Le Chatelier. The property of producing black ware by the action of air charged with tar vapour at a high temperature is found to be intimately related with the pre- sence of iron in the earth; in the absence of iron, a greyish coloration at the most is produced in the interior, nearly all the NO. 1556, VOL. 60] carbon remaining in the outside crust. The most satisfactory results were obtained by acting with acetylene for a quarter of an hour at 450 to 480° upon an earth containing about 2 per cent. of iron oxide. The objects are then removed to a furnace and baked at about 1200°, the hardness thus obtained being comparable with that of porcelain.—On Egyptian porcelain, by M. H. Le Chatelier.—Action of sodammonium and potassam- monium upon tellurium and sulphur, by M. C. Hugot. With the alkali in excess the products were NaS, K,S, NasTe, K.Te, all! white amorphous substances, soluble in water, but insolublen im liquid ammonia, and incapable of absorbing ammonia. With the sulphur or tellurium in excess, the products are Na,S;, K,S., Na,Te;, K,Te, all crystalline, soluble in water and in liquid ammonia, and capable of absorbing ammonia gas.—On the com- position of the albumen of the seed of the carob tree, by MM. Em. Bourquelot and H. Heérissey. It has been shown in a previous paper by the authors that a mixture of mannose of galactose results from the careful hydrolysis of the albumen from carob seeds. It is now found that four-fifths of this albumen is con- stituted by a mixture of the anhydrides of mannose and galactose (mannane and galactane). The carob seed isa very advantageous source of crystallised mannose.—Detection and estimation of free phosphorus in oils and fatty bodies, by M. E. Louise. The oil or fat is dissolved in twenty times its volume of ordinary acetone, and a concentrated solution of silver nitrate added. The silver produced is assumed to be proportional to the amount of free phosphorus present.—On the coloration of the Tunicates and the mobility of their pigmentary granules, by M- Antoine Pizon.—Action of different luminous radiations upon silkworms in different stages, by M. C. Flammarion. CONTENTS. PAGE ithe) Book of thesDeadianiamens -| - « necmemEeS Hamilton’s Quaternions, By C. Gok... Spee eee Ong Our Book Shelf :— Tilden: ‘‘A Short History of the Hircpress of Scientific Chemistry in our own Times”. ton yee Sa Meunier: ‘‘ La Géologie Expérimentale” cskvi RRR OS Forrest : ‘‘ The Fauna of Shropshire.’ "—R.L.. . . , 388 Lévy: ‘* La Pratique du Maltage.”—A. J. B. Bidwell; ‘‘ Curiosities of Light and Sight” ... . 389 Letters to the Editor :— A Curious Salamander. (J///ustrated.)—Dr. Charles Minor Blackford . . 389 Paleolithic Implement of Hertfordshire Conglomerate. (Jdustratea.)—Worthington G. Smith .. . 390 On the Calculation of Differential Coefficients from Tables involving Differences ; with an Interpolation- Formula.—W. F. Sheppard : 39° Apparent Dark Lightning Flashes. __Dr. William ij, S. Lockyer . = - 391 Subjective Impressions due to Retinal Fatigue _w. ee Millar eee 395 Mathematics of the Spinning: Top. ‘Prof. A. G. Greenhill, F.R.S... . 391 On Spectrum Series. \(uasiraied.) noe By Sir Norman Lockyer, K.C.B.,F.R.S. ... . 392 Note on the Discovery of Miolania and of Classe: therium (Neonylodon) in Patagonia. (///ustrated.) . By Dr. Francesco P. Moreno. ......... 396 Mryjohn Cordeaux, By AQINGes = - 2 2 | o omemsoS Notes) = - : 5 CONOR als Ses Our Astronomical’ Column: os Holmes’ Comet 1899 a (1892 mE) PE oc COS The Paris Observatory ... . Tos 6 fe OZ The Bulletin AS Orr i CONES wok lees mbhetSun’s Heater .: -aeme 5 OS OMENS Oo o CO Iron and Steel Institute... . G5 o wor Magneto-Optic Rotation and its Explanation bya Gyrostatic System. (J///ustrated.) II. By Prof. Andrew Gray, F.R.S._ . Tac «eke eA OF: University and Educational Wereiiccnce =. eA O7, Societies and Academies.............- 408 eed OU RE 409 THURSDAY, AUGUST 31, 1899. PLANTS AND THEIR ENVIRONMENT. Les Végétaux et les Milieux Cosmigues (Adaptation— Evolution). Par J. Constantin. Pp. 292. Avec 171 gravures dans le text. (Paris: Félix Alcan, 1898.) HIS little book has some admirable points which can be urged in its favour, and it also exhibits lacune which are a source of irritation to the reader. Chief amongst its more obvious defects is the entire lack of reference to literature. In a book of this sort such references are particularly desirable, as it will be read by many who may have no special first-hand acquaint- ance with the sources whence M. Constantin draws his facts. The book is well conceived and clearly written, though of course it makes no claims to be considered as an exhaustive treatise. The various kinds of surroundings in which different plants live, and the nature of the corresponding response on the part of the plant organism forms the main thesis of the book. An example will serve to illustrate the author’s method. The cold temperate climate on the whole tends to favour the production of dwarf plants, whereas the colder seas, as is well known, are the home of the largest alge. Ultimately both of these apparently contradictory effects are to be explained on nutritional grounds, the short period of terrestrial vegetation, during which alone assimilation can proceed, is to be contrasted with the more equable temperature of the sea, and especially with the fact that nutrition is favoured, in the case of aquatics, by lower temperatures, since gases are more soluble, and hence more abundantly at the disposal of the organism, than would be the case in warmer water. Similarly, the effects of light, gravity and aquatic sur- roundings upon the structure and form of plants are dis- cussed, and the reader will find much to interest him in the pages which deal with these topics. At the same time it must be confessed that the treatment strikes one as somewhat superficial at times, especially when the author wanders into the paths of theoretical inter- pretation. M. Constantin shares the belief, emphatically held by some German botanists, in the direct influence of the environment not only as modifying the form in the individual but also as impressing, without the aid of natural selection, that form on the species as part of its inherited stock ; and one chapter is devoted to an attempt to establish the thesis that acquired characters are inherited. As usual, however, in such cases, the mean- ing of ‘‘acquired characters” is not rigidly defined, nor separated from latent possibilities in the organism which the environment is able to emphasise simply by providing that stimulus which ensures their positive appearance. Some of these variations, responsive to the external requirements, are certainly very difficult of explanation on the doctrine of selection, but the opponents of this NO. 1557, VOL. 60] theory sometimes seem to overlook the fact that, in the first place, it is not in the least necessary to assume that | variations will be s/ég#¢,; they are often, on the contrary, in the case of specially plastic individuals, very extensive when these are subjected to a change of environment. And, in the second place, it is not necessary to suppose that any given species, and far less any individual, will vary equally in different directions round its average or mean. A very slight acquaintance with horticultural operations is enough to convince any one that certain races are specially plastic as regards one organ, whilst in others modification is most easily provoked in a differ- ent one. And selection, acting as it essentially does by eliminating those which conform less readily to the require- mentsof the environment, can hardly be dismissed, as M. Constantin dismisses it, as of relatively small importance in the evolution of species. But the difficulty really does exist if we only assume the possibility of slight variation ranged equally round a mean. In this case, of course, it is difficult (apart from isolation, physical or physiological) to see how a new species could be evolved at all when the chances of intercrossing are considered. But, as has been indicated, such a restriction is entirely gratuitous, and, furthermore, is contradicted by experience. The facts adduced by the author, drawn from the studies of Schiibeler and Bonnier, on the sudden evolution of spring- from autumn-wheat, hardly seem to help the case of the inheritable influence of the surroundings at all. For it is conceded that if autumn- wheat be sown in spring, a large percentage of the plants do not ripen fruit. Those that do succeed may, however, be supposed so to develop because their latent possibilities in this direction were greater than those possessed by their unsuccessful comrades. Next year, of course, the sowings obtained from the survivors will possess the same character for speedy growth and early maturity ina far larger average number, since the parents a@// had clearly a trend in the required direction. But it is misleading to speak of this as an inherited effect due to the impressed action of the environment, ze. the inheritance of an acquired character, for it is clearly nothing more than the encouragement of possi- bilities which were latent before, and, but for the changed conditions, might never have been raised to the position of criteria of existence at all, But this confusion between an outside moulding influence (e.g. mutilation) and the evoking from the plastic organism of a suitable response to the environ- ment imposed by new conditions, is very wide-spread ; and although the difference is in reality one altogether of kind, it is often in practice overlooked. A good summary is given of some of the interesting results obtained by French investigators on crossing races and species, but some of the other chapters strike one as rather weak, e.g. those dealing with the action of gravity on plants. The account of aquatic plants is also somewhat disappointing, especially as the author has himself worked in this branch of the subject. Nevertheless, the book is’ worth reading, bringing together as it does a considerable body of scattered facts which are lucidly arranged within a moderate number of pages. nets J. a 410 NALORLE [AucusT 31, 1899 THE NEWTONIAN POTENTIAL. Théorie du Potentiel Newtonien. By H. Poincaré. Pp. 366. (Paris: Georges Carré and C. Naud, 1899.) HE course of lectures given by Prof. Poincaré at the Sorbonne during the session of 1894-5 has, under the editorship of Dr. Edouard Leroy and M. Georges Vincent, assumed the form of a text-book on attractions and the theory of the potential. The subject-matter naturally falls into two sections, one referring to special properties of potentials of linear, superficial and volume distributions, and the other deal- ing with Dirichlet’s problem and its solution. It is rather a pity that this division was not adhered to in the arrangement of the text. Chapter vi., dealing with the potentials of magnetic shells, is quite out of place in the middle of Dirichlet’s problem, and should logically have preceded the two previous chapters. In opening what we have regarded as the first subject, M. Poincaré introduces concurrently with the Newtonian potential the logarithmic potential corresponding to the law of the inverse distance, which represents the two- dimensional potential of infinite cylindric distributions. The first chapter, which includes calculations of the potentials of rods, cylinders, spheres, and other simple forms, deals with potentials of bodies at external points. It contains a brief account of Legendre’s coefficients. In passing to the interior of the attracting mass in Chapter ii., the question of the convergency of the integrals repre- senting the potential and its derivatives naturally necessitates a brief digression on convergent integrals in general. Chapter iii. deals with potentials of linear and superficial distributions of matter, and naturally leads on to the misplaced Chapter vi., which treats at considerable length of “double layers” (douwdles couches)—in other words, magnetic shells. The second subject opens in Chapter v., where Dirichlet’s problem is stated, the principal properties of Green’s function are proved, and the equivalence of the two problems is established. In the next chapter Prof. Poincaré gives the solutions of Dirichlet’s problem for a circle and a sphere, and deals with the properties of con- jugate functions and conformal representation in two dimensions. Chapter vii. treats of the method of ex- haustion (éa/ayage), and the remaining eighty pages contain a fairly detailed account of Neumann’s method and its extensions. Lecture notes are rather apt to be deficient in explan- ation on points which have either been taken for granted by those who transcribed them, or have been incidentally explained in a conversational way by the lecturer. Any one not starting with a previous knowledge of the definition of the potential would hardly find M. Poincaré’s opening very clear. In first “letting” /,'(7,) be the attraction at distance 7, and afterwards defining the potential as — 3/(7) it ought to be explicitly stated that /\'(7,) is the derived function of the subsequently intro- duced function f(7,). Moreover, why should the con- stant of integration in /,(7,) be taken as zero in the Newtonian and as —# log 7) in the logarithmic poten- tal? A few additional words of explanation in such cases would often save readers from wasting time over unnecessary difficulties. NO. 1557, VOL. 60] There are many problems which, although belonging to the subject proper of attractions and potential, are not included in the present volume. The potentials of ellipsoids are untouched, Lame’s ellipsoidal harmonics being dismissed with a mere reference. Then, again more might have been said about spherical harmonics. It will be seen, however, that M. Poincaré’s lectures have reference to the general theory of the potential rather than to special problems, which find appropriate treat- ment elsewhere. As an introduction to this theory dealing at some length with Dirichlet’s and Neumann’s developments, M. Poincaré’s volume bids fair to be a useful addition to the library of college lecturers as well as of the more advanced class of mathematical students. Ga HB: OUR BOOK SHELF. Faune de France—Mammuyéres. By A. Aclogue. Pp. 84; Figs. 9. (Paris: Bailliére.) As compared with that of the British Isles, the mam- malian fauna of France is much more extensive, com- prising a number of Mediterranean types quite unknown among the former. It is therefore, altogether apart from patriotic considerations, well worthy of being separately monographed. This task kas been undertaken by the author of the present little volume ; and although in the main the very condensed descriptions given appear satisfactory so far as they go, we cannot but regret that the work was not written’ more on the lines of Bell’s “British Quadrupeds.” The volume commences with an illustrated dissertation on the characteristics of, first, the Vertebrata and then of mammals ; and in this part we notice that on p. 21 the author figures the skull of a bat as that of a mole, and also one of a porcupine as that of a second representative of the insectivorous order. The illustrations are, indeed, very discreditable, the only passable ones being those borrowed from other works. In these days of cheap ‘“process-blocks” it does seem inexcusable to issue caricatures like those in the present volume. The type, too, is extremely small. The descriptions of the genera and species, although, as already said, very short, are sufficient to admit of their identification. Some of the terms used, such as (p. 73) “ Bosidi”—the equivalent of Bovzdae—sound, however, somewhat strange to English ears ; and it may be added that the nomenclature generally is by no means altogether up to date. Moreover, even if it be considered advisable in a work of this nature to introduce the ordinary indigenous domesticated animals, such as sheep and oxen, there seems little to justify the inclusion of such a palpable foreigner as the guinea-pig. The best we can say is to express the hope that the author may, before long, see his way to reissue what forms the rudiments of a very useful work on a scale more commensurate with the importance and interest of the subject. Anatomical Diagrams for the use of Art Students. By James M. Dunlop. Pp. 72. (London: George Bell and Sons, 1899.) As to how much or how little knowledge of anatomy the art student should possess is a matter on which opinion is very much divided. Your youthful impressionist is apt to sneer at anatomy ; as arule, his contempt for the sub- ject is revealed in the construction of the forms he repre- sents. On the other hand, the more serious-minded and studious of the artistic fraternity, those who, by hard work and diligent study, are laying the foundations upon Aucust 31, 1899] NATURE AI! which a true impressionism can alone be based, have found and do find the study of anatomy a help in their work. That such knowledge may be abused is not sur- prising; the example of the unfortunate Haydon might serve as a warning. Yet there are plenty of instances in modern work in which this knowledge is duly restrained. Leighton had a keen appreciation of anatomical detail, and his bronze of an Athlete struggling with a python is likely to outlive most, if not all, his pictorial efforts as a work of art. Books on so-called artistic anatomy, written usually by surgeons and anatomists having little or no knowledge of the requirements of artists, have, as a rule, been pre- pared by “boiling down” the technical treatises supplied to medical students. It is to Dr. Paul Richer that we are indebted for having dealt with the subject in an appreciative spirit; he approaches it, not merely from the standpoint of the anatomist, but from that of the artist as well. His method is to represent the figure in action in different poses, and submit a chart explanatory of the various structures on which the surface contours depend, having first, of course, supplied his readers with such information regarding the bones and muscles as is necessary to enable them to understand and appreciate the diagrams. It would be difficult to over-estimate the value of his book; its cost, however, places it beyond the reach of most students. When an art-master produces an atlas of anatomical diagrams, we naturally expect to have fresh light thrown on the subject, together with a keener appreciation of the requirements of art students. We are not inclined to be too exacting with regard to the anatomical details if only we can get some further insight into their appli- cation to the study of the human figure. In an interesting introduction to the present volume, Prof. Cleland, whose artistic sympathies are well known, makes use of the statement that the work occupies “‘oround which has not hitherto been taken up.” With this opinion we cannot agree ; for, as a matter of fact, the bulk of the illustrations in this atlas are reproduc- tions, somewhat diagrammatically treated, of tracings or combined tracings of Richer’s drawings. To these the author has had no hesitation in affixing his name with- out, so far as we can ascertain, once mentioning the source from which his figures are derived. The only features in the book which display any originality are the plates in which those parts of the skeleton having a direct relation to the surface contours are blocked in in distinctive colours. The absence of explanatory text, as well as the lack of reference to the contours of the figure in action, seem to us to minimise its value as a text- book to be placed in the hands of students. As dia- grammatic reproductions of Richer’s figures, the plates in this atlas may not be without value. We confess, however, to a preference for the originals. By R. L. Taylor. (Manchester: Thomas Wyatt, 1899.) THIS little book, like many others which have appeared during the past few years, should assist the progress of rational methods of teaching elementary chemistry. It consists of a series of nearly a hundred simple experi- ments to be performed by or for pupils commencing the study of chemistry. The subjects illustrated by the ex- periments are elements and compounds, chemistry of the air, water, acids and alkalis, carbon and carbon dioxide. Pupils who perform the experiments will obtain a sound knowledge of the nature of chemical changes, and of the properties of some common substances. Fig. 3, illustrating the preparation and collection of oxygen from potassium chlorate and manganese dioxide, shows a liquid in the flask instead of the oxygen mixture. NO. 1557, VOL. 60] Chemistry for Continuation Schools. Pp. 52. LETTERS TO THE EDITOR. (The Editor does not hold himself responsible for opinions ex- pressed by his correspondents. Netther can he undertake to return, or to correspond with the wrtters of, rejected manuscripts intended for this or any other part of NATURE. No notice zs taken of anonymous communications.) Blue Ray! of Sunrise over Mont Blanc. LOOKING out at 5 o'clock this morning from a balcony of this hotel, 1545 metres above sea-level, and about 68 kilo- metres W. 18° S. from Mont Blanc, I had a magnificent view of Alpine ranges of Switzerland, Savoy, and Dauphine ; perfectly clear and sharp on the morning twilight sky. This promised me an opportunity for which I had been waiting five or six years; to see the earliest instantaneous light through very clear air, and find whether it was perceptibly blue. I there- fore resolved to watch an hour till sunrise, and was amply rewarded by all the splendours I saw. MHaving only vague knowledge of the orientation of the hotel, I could not at first judge whereabouts the sun would rise; but in the course of half an hour rosy tints on each side of the place of strongest twilight showed me that it would be visible from the balcony; and I was helped to this conclusion by Haidinger’s brushes when the illumination of the air at greater altitudes by a brilliant half-moon nearly over- head, was overpowered by sunlight streaming upwards from beyond the mountains. A little later, beams of sunlight and shadows of distant mountains converged clearly to a point deep under the very summit of Mont Blanc. In the course of five or ten minutes I was able to watch the point of convergence travel- ling obliquely upwards till in an instant I saw a blue light against the sky on the southern profile of Mont Blanc ; which, in less than the one-twentieth of a second became dazzlingly white, like a brilliant electric arc-light. I had no dark glass at hand, so I could not any longer watch the rising sun. KELVIN. Hotel du Mont-Revard, above Aix-les-Bains, August 27. A Fold-Making Apparatus for Lecture Purposes. I HAVE found the piece of apparatus which I am about to describe so effective for ‘lecture experiments, that I venture to think that others engaged in geological teaching may be glad to possess details as to its construction and mode of operation. The machine (Fig. 1) consists of two parallel wooden rollers, about 3 feet apart. Each is about 12 inches long and 4 inches Fic. 1. in diameter. A shaft at right angles to their length turns the two rollers in opposite directions by means of toothed bevel wheels, the shaft itself being driven by a worm wheel and worm, the latter being actuated directly by the handle. One turn of the handle only causes ~ turn of the shaft and rollers, so that a very slow motion can be imparted to the latter. A sheet of 1 The ‘Rayon Vert” of Jules Verne is the corresponding phenomenon at sunset ; which I first saw about six years ago. 412 NALURE [ AucusT 31, 1899 { india-rubber about 3-inch thick, firmly attached by a slot and screwed bar to each roller, completes the ar rangement. The rollers being wound through about one entire revolution, and the india-rubber being thus stretched tight, layers of cloth, clay, paste or other giving material, are laid upon it. The handle is then turned in the reverse direction, and the india- | rubber gradually released. Folds are in this way shown slowly growing—the broad elastic band simulating the contraction of a and 3, cloths are seen portion of the earth’s crust. In Figs. 2 Fic. 2. Fic 3. folded thus—first, without superincumbent weight, and second, with a weight of 30 lbs. That the larger folds are those generated at the surface, and the smaller and more numerous those produced under pressure (z.e. at great depths), is here made evident. | By substituting blocks of stone or wood for ordinary weights above the cloths (Fig. 4) and repeating the experiment, some of the relations between folding and faulting are clearly shown. | the best score. Fic. 4. If clay be used instead of cloths, all the results of Favre’s well-known experiments (Arch. @. Sctences Phys. et Nat., 1878, and also NATURE), and many of those described by Cadell, Bailey Willis and others, can be obtained, and with the exercise of a little ingenuity it is easy to vary the experiments so | as to reproduce a large number of the fold-forms known, and to illustrate their consequences—thrusts, faults, &c. This machine was made for me in 1880 by the late Mr. C. D. Austen, of Newcastle-upon-Tyne, from my designs. G. A. LEBOUR. The Durham College of Science, Newcastle- upon-Tyne, August 18. Scoring at Rifle Matches. IN his letter to NATURE of August 17, Mr. Mallock appears to assume that there is such a thing as abstract ‘‘ accuracy ”’ in estimating the value of a marksman’s score. The method in use at Bisley is, as I understand him, to be regarded as a rough approximation to the accurate method, whether the best available approximation or not. Is it not rather the case that the standard of accuracy is itself arbitrary, and what the authorities at Bisley have established is not an approximation | to an ideal standard, but is to be regarded as a real standard of cellence ? | In result Mr. Mallock’s ‘‘ accurate” method is this: in | his notation any two scores for which R* +p? is the same are of NO. 1557, VOL. 60] e equal merit, or that one for which R*+ p? has the least value is Now, if ‘‘a” be the distance of any shot mark from the bull’s-eye, # the number of shots, R?+p?=3a2/z, Mr. Mallock’s standard, then, is that the best score is that for which the sum of the squares of the distances from the bull’s- eye is minimum. I see no reason why this method should be regarded as accurate par excellence, except the analogy of the method of least squares. But the analogy is misleading. Where the method of least squares is applicable, the object is to find the most advantageous value of an unknown quantity to be deduced froma number of observations. An accurate value of the quantity does exist. And of two or more results deduced from the observations, that which is nearer to the accurate value is always better than one more remote, however near to the truth either may be. In rifle shooting, on the other hand, there is generally some finite *space—e.g. the port-hole of an enemy’s ironclad, such that all shots which pass through it are of practically equal value, and all shots which do not pass through it are of little or no value. This is much more accurately represented by the Bisley method than by the method which Mr. Mallock would sub- stitute for it. S. H. Burspury. THE only remark I should wish to make on Mr. Burbury’s letter is that every shot on the target is truly the record of an observation, and that there is every reason to treat these records as far as is practicable by the methods which apply in obtaining the best means of a number of observations. Of course, it is only in the case of ‘‘centre of target” competitions the “R24? a minimum ” test applies. Prizes might well be given for close grouping, with a penalty depending on the mean distance of the group from the centre of the target. August 22. A, MALLOCK, Spectrum Series. Stk NorMAN Lockyer’s lectures on ‘‘Spectrum Series”’ seem to show very clearly the important fact that there is a close connection between the valency of an element and the lines in its spectrum. The connection indicated is as follows :— Nonvalent elements yield spectra with single lines. Monovalents yield doubles, Divalents yield triplets. On turning to the list given in NATURE (vol. lx. p. 370), it | will be seen that helium, by yielding doubles as well as singles, and cobalt, by yielding doubles only, are practically the only discordant cases in Sir Norman Lockyer’s list, since aluminium | and indium are trivalents, and their anomalous behaviour in yielding’ doubles only can perhaps be explained. August 26, W. SEDGWICK, Magnetic ‘‘ Lines of Force.” IN some text-books and by some lecturers (e.g. Prof. A. Gray, as reported in Nature of August 17, p. 379), the lines of magnetic force are said to be the curves along which iron filings are marshalled when sifted over a piece of card laid over a horizontally placed magnet. Surely this is hardly correct. The true lines of magnetic force must be represented, like those of all other radiant forces, by radiating straight lines drawn through the points of action of the resultants of all the forces residing in the individual mole- cules of a given magnet (such points, though varying in position with the position of a magnetic body in the field, being often referred to as fixed ‘ poles”). The symmetrical figures traced out by iron filings merely show, of course, the directions in which a line joining the poles of a very short magnet will lie in different parts of a magnetic field, under the influence of the true lines of force. IBS IR ae August 29. Critical Pressure.—A Suggested New Definition. THE critical pressure of a substance is commonly defined as ““the least pressure that will suffice to reduce that substance from the gaseous to the liquid state when at its critical temperature.” But this definition contemplates the matter solely from the stand point of what occurs at the critical temperature, and I think it Aucust 31, 1899] would sometimes be an advantage to have one presenting a broader view and making no reference to any specific temper- ature, just as the ordinary definition of critical temperature makes no reference to any specific pressure. Now, if in a fv diagram we draw the curve formed by the liquid and vapour lines, the indicator points corresponding to the ‘‘mixed state” (ze. part vapour and part liquid, each more or less distinctly discernible) lie wholly within the region bounded by this curve and the axis of volume ; also the ordinate of the highest point of this curve—where, of course, the tangent is horizontal—corresponds to the critical pressure, and the “critopiestic” or critical pressure line is the said horizontal tangent. All horizontal lines below the critopiestic intersect the region corresponding to the ‘‘ mixed state,’’ while those above do not, thus showing that at pressures below the critical the substance changes from gas to liquid, or wzce-versa, by the ordinary process of condensation or evaporation, z.e. by passage through the mixed state, while above that pressure this process does not take place, but the change occurs by continuous and imperceptible transition. Of course all this accords with experiment, as is pointed out in several, though by no means all, the standard text-books. Thus on p. 123 of the new edition of Clerk Maxwell’s ‘* Theory of Heat,” revised by Lord Rayleigh, we read :—“If we begin with carbonic acid gas at 50° F. we may first heat it till its temperature is above the critical, 88° F. We then gradually increase the pressure to, say, 100 atmospheres. During this process no sign of liquefaction occurs. nally we cool the substance still under a pressure of 100 atmospheres ta 50° F. During this process no sudden change of state can be observe, but carbonic acid at 50° F. and under a pressure of 100 atmto- spheres has all the properties of a liquid... by this process we have caused the substance to pass from an undoubtedly gaseous to an undoubtedly liquid state without at any time undergoing an abrupt change stmilar to ordinary liquefaction.” Again, on p. 206 of the ‘‘ Text-Book of Physics,” by Mr. Alfred Daniell, we find :—‘‘If CO, gas be exposed to a tem- perature above 30 ‘92 C. and be subjected to any pressure above 73 atmospheres, it will still be a gas: a//ow zt to cool, the pres- sure being kept up, and it will be a liquid after tt passes 30°92 C., and yet the transition ts unobservable.” I therefore propose to define the critical pressure of a sub- stance as ‘* that pressure above which it is impossible to make the substance undergo the ovdinary process of condensation (or evaporation) ”—or if greater amplification is needed as ‘‘ that pressure above which an appropriate alteration of temperature causes the substance to pass from the gaseous to the liquid state or vice-versa, by a process of continuous and imperceptible tran- sition, and not, as happens below that pressure, by fassage through the mixed state.” This definition I have given in my recently published book, “Physics : Experimental and Theoretical,’”’ but the Z¢mes re- viewer, in a paragraph in that paper of July 29, characterises it as ‘* mere nonsense.” I shall be greatly obliged if you will publish this letter, to- gether with your opinion on the validity of my definition. Perhaps also some of your readers may favour me with an expres- sion ot their views. R. H. JupE. Newcastle-upon-Tyne, August 2. Maternal Devotion of Spiders. ON removing some virgin cork from the wall of a consery- atory a short time ago, I was much struck with the way in which a small black female spider clung to her two egg-bags, despite the fact that the piece of cork to which she was cling- ing had been thrown roughly to the ground. When the cork was about to be replaced on the wall, it became necessary to turn the spider adrift, in order to prevent her being crushed. But although the cork was shaken, she declined to budge, and retained a tight hold upon her precious bags. Knowing how fully alive to danger the spider race is in general, I thought that this remarkable instance of devotion to maternal prompt- ings on the part of a naturally sensitive creature ought not to be disregarded. I accordingly removed the mother very care- fully, and placed her on some rockwork, where I noticed she seemed to be very uneasy, moving restlessly about as if search- ing for something. I then took the egg-bags and placed them beside her. As I expected, she seemingly failed to recognise NO. 1557, VOL. 60] NATURE 413 them, or at least manifested a repugnance to them, and ran away for a little distance. Subsequently, however, she re- turned, and proceeded to examine the bags with scrupulous care by means of her palpi; and evidently satisfied with this scrutiny that they were really her own cherished property, she commenced to spin a web about them to secure them in their place. Rennie has described experiments with the females of certain spiders which carry about their egg-bags attached to their bodies. | When one of these spiders was molested, and its bag dragged with a stick, the mother seemed to lose all sense of personal danger in her anxiety for her unhatched offspring, and fought vigorously to retain her precious egg-bag. When forcibly deprived of the bag, she manifested great distress, and commenced a search for it, and, not finding it, she refused to leave the spot, seeming to be quite indifferent as to her fate. The curious part of the story is that when the egg-bag was finally restored to her, she refused to touch it, being apparently quite unable to recognise her property. In another case the spider regained possession of the bag as it was being withdrawn, and immediately refixed it in its former position. My spider apparently recognised her egg-bags without much difficulty, and, furthermore, seemed to be alive to the danger to which they were exposed in their new situation by her act of spinning a protecting web without delay. When evening arrived, I observed that she had drawn the bags close up under a sheltering leaf, and was guarding them closely, having placed herself between them. FrANcIs J. RowsBorHaM. August 23. THE CAMBRIDGE ANTHROPOLOGICAL EX- PEDITION TO TORRES STRAITS AND SARAWAK. Ape main object of the expedition was to verify and supplement the anthropological observations that I made in Torres Straits in 1888-89, with the view of the publication of a monograph dealing with the anthro- pology of the islanders using that term in its widest sense. A few months before leaving I received sucha pressing and enthusiastic invitation from Mr. Charles Hose for the expedition to visit the Baram district of Sarawak, that I felt constrained to extend the scope of our work by accepting his tempting offer. The party consisted of Dr. W. H. R. Rivers, Messrs. C. S. Myers, W. McDougall, S. H. Ray, A. Wilkin, C. G. Seligmann, and myself. The Torres Straits islanders are Papuans, and as they inhabit the remains of the old land communication between Australia and New Guinea it was important that they should be thoroughly studied before it was too late. The islanders have been more or less under mission instruction since 1872, and some time before then the pearl-shelling industry had commenced. Owing to the varied influences of the white man, modification was bound to take place rapidly, and unfortunately in most islands more or less extensive depopulation has also occurred. There are two distinct tribes in the archipelago —the eastern tribe inhabits the Murray Islands, Erub (Darnley Island) and Uga, and the western tribe the re- maining islands. The latter people have been most under the influence of white men, scarcely a pure-blooded native exists in Erub, but the Murray Islands, on account of their remoteness and the difficulties in reaching them owing to numerous coral reefs, have been less visited. As Mer, the chief island of this group is very fertile, and has a population of some 450 people, it appeared to be the best centre for our work. We reached Mer on May 6, 1898, and took possession of the disused mission residence, which we speedily con- verted into anthropological, psychological and photo- graphic laboratories. Here we measured 63 men, 5 women, 30 boys, and 22 girls. The average height of the men is 1°653 m. (5 ft. 5 in.) ; their cephalic index is 77°5. Although reference is made here only to the cephalic index and the height, I may state that we usually made 414 NABORE [AuGUST 31, 1899 twenty-two measurements on the subjects in Torres Straits, New Guinea, and Borneo, besides a number of observations on the skin, hair, eyes, face, &c. Psychological observations were made in the Murray Islands on about 150 individuals. Among the subjects investigated were visual acuity, delicacy of colour sense, colour blindness, binocular vision and visual perception of space; acuity and range of hearing, appreciation of musical intervals ; tactile acuity and sensibility to pain, and discrimination of weight; acuity of smell; simple reaction time to auditory and visual stimuli and choice reaction time ; estimation of intervals of time ; the influ- ence of various mental states on blood pressure ; and the influence of fatigue and practice on the capacity for mental work. By means of colour matches, quantitative records were also taken of the colour of the skin of the islanders. We were fortunate to find two or three old men who were able to tell us about the old customs and cere- monies. A good deal of time was spent in elucidating the long since abandoned sacred Malu ceremonies which were held in connection with the initiation of the youths ; the previous account? can now be considerably aug- mented. Notes were made of various other ceremonies, and whenever possible the ancient sacred songs were re- corded on the phonograph. A large collection was made of sacred stones, including stones about which there is a legend, sorcery stones, fishing and garden charms, rain and fire charms. Numerous legends were also collected, and many of the sites and stones connected with them were photographed by Mr. Wilkin. The old oracle known as “ 7omog zogo,” which con- sisted of a group of large shells on stones, to represent each group of houses on the island, and a shell ‘‘ house” for the zoge, was plotted, and the former method of divination was demonstrated to us. One or two members of the party learnt the constellations on the voyage out ; this enabled us to map some of the native star groups. Attention was also paid to children’s games, and a system of nomenclature was devised which enabled us to record with accuracy the complicated manipulation in the making of the ingenious string puzzles or “‘cat’s- cradle.” Examples of the past and present handicrafts of the people were collected. The construction of the language was carefully studied by Mr. Ray, and the pre- viously published vocabulary increased. The native diseases and their cures were studied with the cognate charms and magic. Messrs. Ray, Seligmann, Wilkin and myself paid a brief visit to the mainland of New Guinea, and visits were paid to Rabao (Yule Island) and to several villages of the Mekeo district. Twenty-eight men were mea- sured: average height, 1610 m. (5 ft. 35 in.) ; cephalic index, 80. As the decorative art of the Mekeo district has not been described hitherto, numerous specimens of lime-gourds, tobacco-pipes, and painted tapa were collected. A short stay was made at Port Moresby, where a number of photographs were taken to illustrate the manufacture of pottery, and a visit was paid to the Taburi tribe that lives behind Mount Warirata. Nine mountaineers from the centre of the Peninsula were measured : height, 1°607 m. (5 ft. 34 in.) ; cephalic index, 80°8, as well as fourteen Koiari from the hilly country: height, 1600 m. (5 ft. 3 in.); cephalic index, 75°53; and six Koitapu of Pert Moresby: height, 1603 m. (5 ft. 3 in.); cephalic index, 771. A study of the Koitapu language was made, which proved that it, like the people themselves, does not belong to the Motu stock. These three groups differ in several respects from the Motu communities that inhabit most of the coast villages from Delena to Aroma ; for example, they 1 Internationales Archiv fiir Ethnographie (vi., 1893, Pp. 140). NO. 1557, VOL. 60] commonly wear hair on the face, and the hair is almost invariably frizzly. A few days were spent at Bulaa (Hula), where we were struck by the relative prevalence of curly and even of wavy hair, and the general lighter colour of the skin: height, 17663 m. (5 ft. 5 in.); cephalic index, 82°5. I intend on a future occasion to discuss the physical char- acters of the Papuans at some length when I have had time to tabulate out our results, and to compare them with those of other workers. At present it appears to me that a short, slightly brachycephalic people live among the mountains, and a similar short mesaticephalic (with a distinct tendency towards dolichocephalism) folk live nearer the coast. It is the latter people who have been repressed by the taller brachycephals of the coast, whose foreign blood is shown by their lighter skin and a marked frequency of curly or even wavy hair. The mountaineers are in no sense a pygmy people, and are not directly related to the Aétas ; they frequently harass and conquer the dolichocephals. Messrs. Ray, Wilkin and myself returned to Murray Island on July 20, Mr. Seligmann remaining behind to see more of the country. Dr. Rivers and Messrs. Myers and McDougall had made a large number of interesting psychological observations during our absence. The two latter left for Borneo on August 24. On September 8 we left Murray Island and arrived at Saguane at the southern end of Kiwai Island in the delta of the Fly River on the rrth. A visit was paid to Iasa, which contains sixteen long houses, each of which is in- habited by members of one totemistic clan, and eleven natives were measured: height, 1°602 m. (5 ft. 3 in) ; cephalic index, 803. Mr. Seligmann rejoined us here. Our next destination was Mabuiag, which we reached on September 17, and had five weeks of good work re- cording old customs, measuring natives, studying language and experimental psychology. In Mabuiag and Kiwai fewer psychological observations could be made, owing to the fact that most of the apparatus had to be taken on to Borneo, but observations on visual acuity, colour vision, &c., were made on over Ioo individuals, many of whom, however, were not natives of these islands. Thirty-three men were measured : height, 1°648 m. (5 ft. 4} in.); the average cephalic index is 811. Although they belong to the same race, and are similar in many respects, there is a noticeable difference between the eastern and western tribe of Torres Straits. Most of their former ceremonies and many of their customs were dis- similar, the languages are quite distinct, and on the whole the western folk are more intelligent. The very slight ditference in the stature may be due to the more abundant food of Murray Island, whereas that of the head form is of greater significance. The difference be- tween an average index of 77 and 81 may not appear large, but there is a distinct difference in the form of the skulls in general from the two islands. I am inclined to believe that the Murray Islanders belong to that dolicho- cephalic stock which certainly occurs on the mainland of New Guinea inthe region known under the general name of Daudai, and which appears to have been pushed back by a somewhat brachycephalic people. Murray Island was unaffected by this movement, but the western islands have not escaped it. I have no desire to push cranio- logical facts too far, and I propose testing this hypothesis elsewhere by cultural evidence. Several writers have expressed an opinion that the natives of Prince of Wales Island and the neighbouring islands are Australians with a strong Papuan mixture. I regard them as Papuans, with a very slight (if any) Australian mixture. The most interesting of our sociological investigations of the Western tribe were those on totemism, maturity customs for men and women, and the beginnings of hero- worship as exemplified in the legend and cult of Kwoiam, the national hero of Mabuiag. Here, as at Mer, Dr. Aucust 31, 1899] NATURE 415 Rivers traced as far as possible the genealogy and relationships of every person on the island. This some- what laborious work has proved a most valuable method of anthropological research, which, so far as I am aware, has not been attempted before for a whole community. The value of this method consists in the large number of accurate sociological data that are accumulated. _ Short visits were paid to other of the western islands of the Straits in which ethnographical facts and specimens were collected. At Mabuiag, and later at Thursday Island, we had an opportunity of studying some North Queensland natives, and the contrast, both mentally and physically, between them and the islanders was obvious. The average height of seventeen Queenslanders was 1°626 m. (5 ft. 4in.), and their average cephalic index was 74'5. We finally left Torres Straits on November 15, 1898. Messrs. Ray, Seligmann and myself reached Kuching on December 12, where we had to remain until January 4; Mr. Ray occupied the time in learning Malay, and I laid the foundations of a study of the decorative art of Sarawak by utilising the collections in the most excellent museum which the Rajah has so wisely and liberally en- dowed. The foundation of the ethnographical collections was the very valuable Brooke Low collection, which the Rajah bought in England and reshipped to its native land. This has been added to from time to time, and, although there is a good deal to be done before all the handicrafts and arts of the natives of Sarawak are fully ulustrated, the museum contains the best and most in- structive collection of Sarawak ethnography extant. The fauna of Sarawak isalso most fully represented, and the value of the collections is daily increased by the well- directed labours of the curator, Mr. R. Shelford. During the north-east monsoon it is impossible for a steamer to cross the bar at Baram Mouth, and this necessitated our proceeding to Limbang, where we had to remain a few days whilst messengers were sent to Mr. Hose. We then had to journey some 200 miles in boats up the Limbang, Madalam and Trikan rivers, and after walk- ing across the watershed at the foot of Mount Mulu we descended the Malinau, Tutau and Baram, arriving at Marudi (Claudetown) on January 28, where we rejoined Mr. McDougall, Mr. Myers having been obliged to return home a few days previously. On February 6 Mr. Hose took Messrs. Ray, MacDougall and myself an up-river trip, Mr. Seligmann was busy studying wpohk (upas), tuba and other poisons ; later he stayed some time among the up river Kayans. We went over 200 miles up the rivers Baram, Tinjar, Dapoi and Lobong, and saw many in- teresting scenes, and gained further experience of the jungle vegetation of a typical tropical land. At Long Puah we witnessed the ceremony of moving the skulls into a new house from the hut in which they had been temporarily lodged, and then we participated in the ceremony of naming the first-born son of the chief. On the same occasion peace was made between two hostile tribes, and the covenant was ratified in the usual manner by “speaking” to some pigs, that were then killed and their livers inspected for augury. In one village we saw a Punan medicine man exorcise fever from) a white man by means of incantations and obvious thaumaturgics. We gained fair insight into the mode of life and beliefs of several tribes of the interior ; we made collections to illustrate their handicrafts and decorative art ; numerous photographs were taken, which unfor- tunately have not proved a success owing partly to climatic conditions. Physical measurements were made of a large number of natives, and vocabularies collected. We also had an excellent object-lesson in the paternal administration of native affairs that is the keynote of the Sarawak system of government. It was on this trip that I discovered a stone imple- NO. 1557, VOL. 60| ment in a native house, close by the usual skulls and associated with other sacred objects. After great diffi- culty Mr. Hose succeeded in procuring it, and later he secured several other specimens of varied types. With the exception of a specimen in the museum at Oxford of a very different type from any we obtained, and one recently acquired by the Sarawak Museum, these are the only authentic stone implements known from. Borneo. Mr. McDougall and I paid a hurried visit to Mount Dulit, but nothing of interest was collected. Later on Mr. Hose took me to visit Tama Bulan, the great Kenyah Penghulu, who lives on the Pata River. Messrs. Myersand McDougall had previously visited him. Towards the end of our stay in Baram we were pre- sent at a great peace-making, when quite 6000 natives assembled from all parts of the Baram district, and even from beyond its borders. We thus had an unique oppor- tunity of seeing representatives of nearly every im- portant tribe of the Raj. Amongst other incidents we witnessed a canoe race in which about one thousand men competed, and participated in an attempt to /wéa-poison a large lake in which over two thousand men weie engaged. We have now in Cambridge specimens to fairly well illustrate the arts and crafts of the natives of Sarawak. Mr. Ray obtained material for grammars of the two dialects spoken respectively by the Land Dayaks and by the Sea Dayaks, as well as notes upon several other languages. Vocabularies of over 200 words were obtained in forty-six dialects spoken by various tribes of Sarawak. Mr. Myers made numerous psychological observations. Mr. Seligmann studied native medicine, &c. Mr. McDougall paid special attention to the question of the relations of men to animals and plants in Borneo, and helped me with the measurements and physical observ- ations of the natives. In all we measured some 276 natives, the bulk of whom are mesaticephalic or slightly brachycephalic. The following are some of the ap- proximate average indices (the numbers in brackets refer to the number of each tribe that were measured) :— Maloh (7)—probably an immigrant people from Java— 76; Barawan (17), 77°5; Kalabit (10), 78; Kenyah (103), 79—of these the Sibops (5) have the lowest index with 75°5, which gradually rises through the Malangs (20), 76°5, Tabalos (3), 775, Madangs (6), 78, Long Pokun (19) and Lirong (15), 79°5, Long Dallo (12), 80's, Apoh (9), 82, to the Long Sinong Kenyahs (5), with an index of 83°5—this does not appear to be a very homogeneous group ; Kayan (22), 80; Long Kiput (9), 8o0°5 ; Punan (22), 81; Sea Dayaks (53), 83; Malanaus (7), 855 ; Brunei-Malay (1), 85°5. We have not yet had time to study the skulls we brought away. I had an opportunity, however, of measuring five Murut skulls at Limbang, which had an average index of 75° (extremes 73-77'5). It is thus evident that there is a dolichocephalic element in Borneo which may be identical with the Indonesians as defined by de Quatrefages and Hamy in “ Crania Ethnica.” There is also a low brachycephalic element found among the up-river Kenyahs (Long Sinong, Apoh, and Long Dallo), Punans, and to a less extent among the Kayans. The Sea Dayaks are not an indigenous popu- lation ; they probably constituted the advance wave of a later Malay migration. The Malanaus are Moham- medans greatly influenced by Malays, and who very fre- quently artificially deform the heads of their babies, so their relatively high index of 85°5 may be neglected. Although the Punan cephalic index (81) is close to that of the Sea Dayaks (83), the slender pale-coloured forest- dweller is physically very different from the short, sturdy, dark-skinned, low-country agriculturist. We were for- tunate in coming across several groups of Punans, a nomadic jungle folk who are certainly one of the most primitive people in Borneo, and who may, perhaps, be the true autocthones of the country, for there is no 416 MABORE [ AUGUST 31, 1899 authoritative evidence for the existence of Negritos in Borneo. The fascinating promises of Mr. Hose when he sent me his invitation to visit him were amply fulfilled so far as time permitted, and we have to thank him for a most enjoyable and instructive visit. Mr. Charles Hose is well known as a highly successful and enthusiastic naturalist. He has made collections in all departments of the land fauna of Sarawak, and he has monographed the mammals and the birds. His geographical explor- ations are also well recognised ; but it is not generally known that he has a most minute and extensive know- ledge of all that pertains to the numerous and varied natives that have been entrusted to his sympathetic care. I have seen piles of immensely valuable ethnographical manuscript which we sincerely hope will be suitably and speedily published. Not only has Mr. Hose from time to time presented his old University with numerous zoological specimens, but he has entrusted to me an extensive and very valuable collection of ethnographic specimens which he has given to the University of Cambridge. In addition he has presented the unique collection of stone implements and a large collection of human crania, each skull being labelled with its tribe and provenance. I shall endeavour on another occasion to do justice to Mr. Hose’s success as an administrator. What we were able to accomplish was largely due to those personal qualities of a ruler which awaken a feeling of affection and loyalty in the natives. The Cambridge University Press will publish the scientific results of the Expedition in due course asa series of memoirs which will be obtainable separately. The volume on experimental psychology will be written by Dr. Rivers and Messrs. Myers and McDougall, with some supplementary observations on the natives of the mainland of New Guinea by Mr. Seligmann. Mr. Ray has ample matter for a volume on linguistics. The linguistic results of the Expedition were on the whole very satisfactory. Materials were obtained for complete grammars of the two Torres Straits languages, and the vocabularies were revised. In New Guinea the Melanesian languages around Hood Bay were studied, as well as those of Rabao (Yule Island) and the adjacent mainland. In New Guinea also material was obtained to elucidate the somewhat complex structure of the Papuan languages of the Koitapu in the Port Moresby district, of the Cloudy Bay peoples, and of the Kiwai and Mowatta tribes in the Fly Delta. No grammar of any of these languages has hitherto been written. The materials obtained in Borneo for grammars of the two dialects spoken by the Land Dayaks and Sea Dayaks, and vocabularies obtained in forty-six dialects spoken by various tribes of Sarawak have already been re- ferred to. The physical anthropology of Torres Straits and New Guinea will mainly be worked out by myself, but Mr. Seligmann has some additional measurements from the mainland of New Guinea. Dr. Rivers will publish and expound his statistical inquiries. Mr. Myers is making a comparative study of native music. Mr. Seligmann has studied native medicines and charms, and has made various ethnological observations of some interest. Mr. Wilkin has made notes on native houses in New Guinea. The religious ceremonies, legends, and general ethnology will be -treated by various members of the Expedition. Mr. Wilkin took a large number of excellent photographs in Torres Straits and New Guinea, which will be drawn upon for illustrative purposes. As there is no room for them in the present Museum of Archeology and Ethno- logy, the extensive collections are deposited temporarily in a couple of small houses in Cambridge, where, unfor- tunately, they run risk of deterioration. ALFRED C, HADDON. NO. 1557, VOL. 60] WHY PEOPLE GO TO SPAS, (EN observer who has the curiosity to pass in review the modern methods of medical treatment cannot fail to be struck by the increasing amount of attention which is being paid at the present time, both by the laity and the profession, to the spa treatment of disease. The fact that many thousands of patients flock annually to the different health resorts to seek relief from their ills, and the idea which prevails among a large section of the educated public, chiefly the well-to-do classes, that their existence is not complete without a yearly visit to one or other of the many spas, either at home or abroad, and that for their bodily well-being an annual “cure” is necessary, are phenomena which call for comment and demand explanation. The practice is by no means of recent growth, for it finds its origin in the almost universal belief, prevalent in ancient times, in the efficacy of natural mineral waters and baths in the cure of disease. Many instances of this might be quoted. The waters of Spa in Belgium were celebrated in the time of Livy ; the Romans built Bath in England, and fully recognised the value of its springs ; and they in turn derived their fond- ness for bathing from the Greeks. There is not want- ing evidence to show that more ancient civilisations appreciated in a rude way the benefits to be obtained in this direction from the resources of nature. Throughout the middle ages the same belief was held, and many were the pilgrimages to the various springs then known. In the present day the same idea, shorn of much of the superstition that formerly clung to it, still prevails, and each watering place claims annually its numerous devotees. Not only among the laity is the assurance of the therapeutic value of natural mineral waters and baths firmly rooted, though doubtless there still remains a substratum of lingering superstition as a part foundation of that assurance, but also by the medical fraternity their utility is accepted, as is witnessed by the freedom with which their patients are sent to take the waters of this or that spring. In the minds of the latter, however, super- stition has been replaced by knowledge, and they are well assured that such treatment has a definite and real value. ; It becomes, then, a matter of interest to seek answers to the following questions: Whether, in the light of modern knowledge and research there is a solid founda- tion in fact for the faith that is placed by patients and their doctors in the utility of bathing and water-drinking ; whether such measures possess any advantages over treatment by ordinary medicinal means ; whether the lines of treatment followed at spas cannot be carried out equally well at the patient’s home, and the necessity for a perhaps inconvenient visit to a watering place thereby be obviated ; and, lastly, whether equal facilities for such treatment, and results equally good, are not obtainable in this country as at similar places on the continent ? ; Up to comparatively recent times the use of waters and baths in the cure of disease was purely empirical. Through long experience and repeated trial it came gradually to be ascertained that certain waters were beneficial in certain cases, and certain kinds of baths produced certain effects ; wherefrom was elaborated a system of spa treatment on more or less rule of thumb principles. The exact nature of the action of these agents, the physiological effects they produced and the pathological conditions they influenced were ill-under- stood; the rationale, in short, of the treatment was wanting. Of late years, however, a large amount of sound scientific work has been done in this department of medi- cine. The action of mineral waters and baths has been made the subject of definite experiment and the results obtained applied to the perfection and extension of the methods ; and thereby this branch of therapeutics, which Avcust 31, 1899] formerly afforded tempting opportunities for scornful criticism on the part of the more advanced members of the profession, has now been placed on a firm scientific basis, and the ancient faith in it fully justified. In this as in many kindred subjects the lead was taken by Germany, and as the result of much painstaking research a large amount of literature has appeared re- lating to the various spas in that country. Latterly the home watering places, such as Bath, Buxton, Droitwich, Harrogate, Leamington, Llandrindrod, Strathpeffer and others, have been brought more prominently before the notice of medical men, and through them to the public, by reason of similar research work conducted on scien- tific lines into the nature of the action of their respective waters and baths, by which their claims to equality with, if not superiority over, many of the continental resorts have been abundantly demonstrated. To illustrate this let us take Harrogate as an example, as possessing the greatest numberand most varied assortment of mineralsprings, and the most complete bathing establishment in this country, if not in Europe, and consider it with regard to its waters and baths. The former, some eighty in number, may be classified into certain groups of saline-sulphur waters, alkaline-sulphur waters, pure sulphur waters,® saline- F _x.—Entrance-hall and pump-room at the Royal Baths, Harrogate. chalybeate waters, and pure chalybeates, each group em- bracing several members presenting fine gradations in quality and strength. The most important of these are set apart for drinking purposes ; the others being col- lected, stored, and used for bathing. Long experience and trial of the waters has indicated the class of diseases | in which they may be expected to prove beneficial, either individually or in combination, and these fall somewhat definitely into the following main groups, which, however, by no means include all cases which may derive benefit: disorders of the liver, functional or organic ; cases of gout in its many manifestations ; cases of rheumatism and so-called rheumatic gout ; and cases of skin disease. The results obtained have been good, though based upon empirical knowledge, and a consider- able reputation has been built up. In recent years, how- ever, this has been strengthened by experimental work which has been carried out to determine the modus operandi of many of the waters, and the results of these researches have not merely corroborated in the main empirical practice, and furnished reasons for it, but have indicated new directions in which these agents may be advantageously employed. For example, the Old Sulphur NO. 1557, VOL. 60] INA TORE 417 Spring, the most valuable possession of Harrogate, has long been used in the past as a stimulant to the liver in sluggish or congested conditions of that organ. Recent research has shown by experiment on man and on ani- mals that administration of this water definitely increases the flow of bile, as to rapidity, quantity, and the amount of solid constituents. And a further indication of in- creased activity of the liver is proved by an increase in Fic. 2.—Interior of the Turkish Bath. the amount of urea eliminated from the body. It has been used: largely as a valuable remedy in gout, a part explanation of which is furnished by the diminished pro- duction of uric acid, which experiment shows to be one of the effects of this water. It has a well-marked effect on the blood in diluting it and diminishing slightly the amount of hemoglobin, which explains its frequent use in plethoric conditions. The milder sulphur waters have Fic. 3.—Cooling room of Turkish Bath. been shown to have similar effects to a less extent. Further, the group of iron waters have been examined, and their effect on the blood in the building up of haemoglobin repeatedly proved, and other unsuspected results on the general vital processes of the body been discovered, the Chloride of Iron water, for example,. markedly increasing the elimination of urea, and diminishing that of uric acid; the “ Kissingen” water 418 NATURE [AuGusT 31, 1899 increasing the flow of bile without increasing the solid constituents ; and so forth. Research of this description has been and is being carried on in the health resorts of this country, and though finality has by no means been reached, yet such endeavours to add to our knowledge should go far to enhance the reputation of each, to in- crease the confidence of patients who seek health there, and to remove any lingering prejudices that may still remain in the minds of scientific men as to the true worth of such treatment. With regard to the baths, inquiry as to their mode of | action has proved quite as satisfactory as in the case of | the mineral waters. Through the forward policy adopted at Harrogate in providing a new and magnificent suite of baths including almost every variety, and replete with every modern convenience, it is possible there to under- take and carry out any line of balneo-therapeutic treat- ment that may be desired. The methods in use at the continental spas have been adopted and in some cases improved upon, any new development being at once in- stalled and its utility or otherwise determined. The baths available, using the word bath in its widest sense, The factors at work in the human organism that are disturbed in greater or less degree by even simple baths are so many, and their interaction so complex, that it becomes a matter of great difficulty, in the first place to measure them, and, in the second place, to estimate their relative importance ; while in the case of the more complicated baths, where different elements, thermal, chemical or mechanical, are brought into play to disturb these factors, some in one direction and some in another, often apparently in direct opposition to each other, the difficulty becomes even greater. Thus, while we are able to ascertain approximately the net physiological result in any given case, it is impossible in the present state of our knowledge to do more than hazard conjec- tures as to the exact mode by which that result was produced—to what extent one factor was concerned and to what extent another. Still, in spite of the difficulty, collation of the results of various workers at home and _ abroad enables us te understand in some degree the rationale of bath treatment, and to place it on a sound physiological basis. The influence of bathing in its various forms on the animal economy is profound, and no one who has not specially observed the effects produced can form an adequate idea of how potent that in- fluence is. Broadly speaking, it may be said that the effects produced are the result of changes that take place in the circulatory system, which is the system mainly acted upon by the factors—thermal, chemical or mechan- ical—that may be at work. The heart, driving the blood with its contained nutriment, derived from the alimentary canal, through a closed system of tubing, consisting of arteries, capillaries and veins, enables that fluid to penetrate to all parts of the body, there to deliver up its charge of food to the tissues by interchange of fluid through the thin capillary wall; re- ceiving in exchange the waste products from the tissues, and bearing them away to be eliminated from the system. Variations in the amount of blood, and the force with which it is driven into the circulation at each heart beat, and variations in the calibre of the closed system of tubing will, with Greaves.) Fic. 4.—The combined needle and douche bath. may be classified into (a2) Thermal baths, depending for their action mainly on the element of temperature, and including plain water baths, hot and cold, Turkish, Russian, superheated air baths, &c. (4) Thermo-chemical baths, in which there is added to the effects of temper- ature the effect of the chemical constituents of the water. ‘They include the saline sulphur baths, alkaline-sulphur baths, saline baths, Nauheim baths, &c. (¢) Thermo- mechanical baths, in which there is added to the effect of temperature the mechanical action of the water in the form of sprays, douches, effervescence, &c., with or with- out the mechanical effect of massage. These include the needle bath, combined needle and douche, running sitz bath, &c., and those with massage, the Aix douche and the Vichy douche. (@) Zhermo-electrical baths, in which a current of electricity, either constant or inter- rupted, is passing through the water. Each and all of these baths have their special effects, and abundant observations have been made to determine them experimentally as a guide to their intelligent use. NO. VOL. 60] 1557) other factors, determine the tension of the circulation, or fluid pressure under which the blood is working—the blood pressure, as it is called. These variations are controlled by a nerve apparatus, the vaso-motor mechanism, whereby dilatation of vessels in one region of the body is compensated for by contraction in another, and the average level of blood pressure main- tained, or changes produced therein. On the integrity of this nerve mechanism, and the perfect performance of its functions, the maintenance of health largely depends, for by it the ebb and flow of vessel constriction and dilatation is controlled, and the circulation enabled to adjust itself to the rapid succession of changes that take place in the environment of the organism—changes due to gravity, posture, exercise, digestion and the like. Further, on these changes in blood pressure depends to a large extent the ebb and flow of fluid through the capillary wall, whereby nourishment is conveyed to and waste products removed from the tissues; and, con- sequently, where this function is impaired the nutrition of the whole body suffers. By the recent introduction of new instruments it is possible to measure directly the blood pressure in the human subject, and to observe its Harrogate. [ : Aucust 31, 1899] NATURE 419 variations from hour to hour or day to day; and also to } raising it. The chemical constituents of the water in measure the varying calibre of the arteries in the extrem- | the case of the saline and sulphur baths also exert ities. We are thus ableto form a fairly accurate estimate | an influence, augmenting the fall in pressure result- é ing from warm baths. The percussion of water impinging sharply on the skin, as in the needle bath, tends to raise the blood pressure. Massage to: the limbs and body causes a fall in pressure, provided the abdomen be not massaged too vigorously; deep: pressure and manipulation of this part is followed by a marked rise in pres- sure owing to the dispersal of blood from the capacious veins of the viscera into the general circulation. In the Aix and Vichy douches massage 1s combined with warm douching. In the former bath, massage is administered under a simple douche conveyed by a flexible pipe passing over the shoulder of the attendant and playing between his hands, the patient being in the sitting posture. The result on the blood pressure is to produce a fall, the massage and heat acting in the same direction. In the Vichy douche, however, the patient lies in the recumbent position, and is massaged under a needle spray fall- ing from a bracket suspended over the table. Owing to the position adopted, massage of the abdomen is more freely performed, and this, combined with the = ae ‘ ag es ; ‘ Be tonic effect of the percussion of the — —_— : = needle spray, produces as a net result Greaves.) (Harrogate. a rise in pressure. Fic. 5 —The Aix douche. The above considerations as to the mode by which tissue change is of the conditions of the circulation, and from these observ- | stimulated and nutrition modified by agents brought ations to infer the completeness or otherwise of the | to bear on the circulatory system, serve to explain nutritional processes on which depend the well-being of | certain more remote effects experienced as the result the individual. In different morbid conditions the blood pressure may de- viate considerably from the normal, the vaso-motor mechanism be im- paired, and the free interchange of blood plasma and tissue fluid be defective, to the detriment of the or- ganism. Experiment has shown that the blood pressure is markedly affected by baths, some procedures having the effect of raising it and some the re- verse. The effect, though at first temporary, 1s cumulative, so that a permanent modification of pressure may be obtained, from which it fol- lows that an intelligent use of bathing as a therapeutic agent can so act on the circulatory system as to regulate the blood pressure, restore the normal mobility of the vessels, promote the interchange of tissue fluid, and pro- foundly medify nutrition. By means of these new methods we can watch closely the changes occurring under treatment, and can adjust the latter to the requirements of any particular case with a delicate nicety. A few instances may be given of esi é a 3 the effect of various baths on the [Greaves.] : ; (Harrogate. blood pressure. Heat in all forms, Fic. 6.—The Vichy douche. whether dry as in the Turkish bath and superheated air baths, or moist as in the Rus- | of baths. To enter into these in detail is impos- sian bath, or the simple immersion bath, lowers the | sible within the limits of an article of this description: pressure. Cold, on the other hand, has the effect of | suffice it to mention one bath only. The Aix douche NOW U5g 7 MOL. Co] 420 NATURE [AuGusT 31, 1899 EEE SUSESS EDS nnnreeeeeeemnmeeeeeeeeeeeeeememeeeeeeeeeee eee lhas the effect of increasing the amount of urea eliminated, and the excretion of uric acid is markedly augmented, which fact, viewed in conjunction with the diminished production of uric acid resulting from administration of the old sulphur water, explains the happy results obtained in the treatment of gout by the use of this water and bath, the one diminishing the production of the materies morbi, the other facilitating its elimination. In answer to the question first propounded, it would appear then that modern research has not only abundantly justified pre-existing views as to the value of spa treatment, and has to a large extent provided sound reasons for them, but has also considerably extended its sphere of usefulness, and has uplifted the methods from the dead-level of empiricism to the more exalted domain of rational and scientific therapeutics. The foregoing remarks suffice to show that the home watering places have of late years advanced with the times, and are able to claim equal recognition with the best known continental resorts. The variety of the waters to be found at the different health resorts of this country is such as to cover almost all requirements, and there are few cases indeed which it is really necessary to send abroad. In the matter of baths, also, almost every known balneo-therapeutic procedure is obtainable in Great Britain, and the methods of administration are as carefully supervised and as efficiently carried out as else- where. The one element in which we are unable to compete with our rivals abroad is in the matter of climate, for we cannot ensure the same protracted periods of sun- shine that many of them enjoy. Nevertheless, the weather experienced during the season at the home resorts is not necessarily incompatible with a successful “ cure,” and is indeed preferred by many, by reason of its bracing qualities, to the hot and relaxing climates of some of the continental spas. In estimating the value of spa treatment other factors besides the administration of waters and baths must be taken into consideration ; such, for instance, as change of air, rest, freedom from business anxieties or household cares, regular habits of living—early rising, simple moderate diet, and so forth—all of which play their part in achieving the end in view. Therein lies the superi- ority of spa treatment over ordinary medicinal means in suitable cases, mainly of chronic ailments, and the im- possibility of fulfilling these necessary conditions renders futile the attempt to follow out similar lines at the patient’s own home. Indeed, by many the major influence is attributed to these factors rather than to baths and waters, and in some cases this may be true. But, while recog- nising fully their importance, the foregoing rough indica- tion of some of the modes in which waters and baths have been proved to act suffices to show that to these the predominant influence must be assigned. WILFRID EDGECOMBE. THE DOVER MEETING OF THE BRITISH ASSOCIATION. { NTENDING visitors to the Dover meeting should note that this year the chief railway companies afford additional facilities to members of the Association. They offer a return ticket at a fare and a quarter, issued from September 12 to 20, available for return till September 27. Those who wish to avail themselves of this privilege must obtain from the Secretary a signed cirtificate, which must be given up to the booking clerk when the ticket is purchased. The following railway companies have entered into this arrangement :—The Caledonian, Great Eastern, Great Central, Great Northern, Great Western, London, Brighton and South Coast, London and North Western, London and South Western, Midland, North British, South Eastern and Chatham and Dover. NO. U5R7 OIRO] The usual arrangement for places within fifty miles of the place of meeting still holds good, in virtue of which a return ticket at a single fare may be obtained at Dover on production of membership tickets. These tickets ae available for return on the same or the following ay. The local programme is now in the press. It may, however, be useful to recapitulate the items of general interest which will appear in the programme. SECTIONAL MEETING Rooms. ge spematical and Physical Science—School of Art, second oor. B—Chemistry—School of Art, first floor. C—Geology—College Gymnasium. D-—Zoology—School of Art, second floor. E—Geography—Apollonian Hall. F—Economic Science and Statistics—Co-operative Rooms. G—Mechanical Science—School of Art, ground floor. H—Anthropology—Rifle Volunteer Hall. I—Physiology—Chemical Lecture Room, School of Art. K—Botany—Union Hall. PRESIDENT’S ADDRESS AND EVENING LECTURES, These will be delivered in the Town Hall. President's Address.—On Wednesday, September 13, the first general meeting will be held at 8 p.m., when Sir Michael Foster, K.C.B., Sec.R.S., will assume the presidency and deliver an address. First Evening Lecture.—On Friday, September 15, at 8.30 p-m., by Prof. Charles Richet, of Paris. Subject: ‘‘ La Vibra- tion Nerveuse.” Second Evening Lecture.—On Monday, September 18, at 8.30 p.m., by Prof. Fleming, F.R.S. Subject: ‘ The Centenary of the Electric Current.” ENTERTAINMENTS AND GARDEN PARTIES, Thursday, September 14.—The Chairman of the College Council, Dr. E. F. Astley, the Headmaster and Masters of Dover College, invite members, associates, and holders of ladies’ tickets to a garden party in the College Close, from 3.30 to 6 p.m. The Mayor, Councillor Sir W. H. Crundall, J.P., and the Mayoress, Lady Crundall, invite members, associates, and holders of ladies’ tickets to a conversazione at the Town Hall, from 8.30 to 11.30 p.m. Friday, September 15.—Lord George Hamilton, Captain of Deal Castle, invites two hundred members, associates, and holders of ladies’ tickets to visit the Castle, from 3.30 to 6 p.m. A smoking concert in honour of the President, Sir Michael Foster, F.R.S., will be given by the Local Committee in the Apollonian Hall, Snargate Street, commencing at 10 p.m. A selection of music will be performed by the band of the Royal Artillery from Woolwich, by special permission. Saturday, September 16.—A grand military tattoo will take place on the sea front, opposite Waterloo Crescent, at 9.30. A space will be reserved for members, &c. Admittance on pre- sentation of Association ticket. Monday, September 18.—The Mayor and Lady Crundall invite members, associates, and holders of ladies’ tickets to an “fat home” at the Connaught Park, from 4 to 6.30 p.m. Tuesday, September 19.—On Tuesday afternoon, September 19, a motor-car exhibition will be opened at the Dover Athletic Grounds by the Mayor. Lord Northbourne invites 200 members, associates and holders of ladies’ tickets to visit Betteshanger Park, from 4 to 6p.m. Light refreshments will be offered. Lord George Hamilton, Captain of Deal Castle, invites 200 members, associates and holders of ladies’ tickets to visit the Castle, from 3.30 to 6 p.m. The Local Committee invite members, associates and holders of ladies’ tickets to a garden féte in the Granville Gardens, from 9.30 to 11.30 p.m. The band of the Royal Engineers, from Chatham, will, by special permission, perform a selection of music during the evening. THE MUSEUM. The Dover Museum, in the Market Square, is well worth visit, as it contains a large number of objects interesting both to ~ Tee AvGuST 31, 1899] antiquarians and lovers of natural history, The collections owe much to the care and interest of Dr. E. F. Astley, the hon. curator. The assistant curator will be glad to afford visitors every assistance. The anthropological collection, though small, is interesting, and contains a valuable feathered cloak from the Sandwich Islands, a Maori’s head, and many war trophies from New Zealand. The “ Plomley ” collection of British birds, pre- sented by the late Dr. Plomley, is specially rich in local speci- mens. The collections have been enriched by many gifts from the Hon. Walter Rothschild, who takes considerable interest in the Dover Museum. There is a good collection of British birds’ eggs, including those of the peregrine falcon, once common on the Dover cliffs, but now becoming exceedingly rare. Pre- historic and local antiquities are well represented. The collec- tions of shells, insects and fossils are also noticeable. VISIT OF THE FRENCH ASSOCIATION TO DOVER. On Saturday, September 16, the members of the Association Frangaise pour l’Avancement des Sciences will visit Dover. On their arrival, about 9.30 a.m., they will partake of a light repast at the Lord Warden Hotel. At eleven o’clock there will be a reception at the Town Hall, when addresses of welcome will be delivered. Afterwards various Sectional Meetings will be visited. At 1.30 there will be luncheon in the marquee in the College Grounds. Tickets for the luncheon (price 15s., including wine) will be on sale at the Reception Room. In the afternoon the members of the French Association will visit the Castle and other objects of interest in Dover. VISIT OF THE BRITISH ASSOCIATION TO BOULOGNE, On Thursday, September 21, the members of the British Association will visit Boulogne. A special boat will leave Dover about 8.30 a.m., arriving at Boulogne about ten o’clock. After a reception, the various sections will be visited, and sub- jects mutually interesting to the two Associations will be dis- cussed. At 12.30 the Municipality of Boulogne will entertain the Associations to lunch. The luncheon will be followed by a Reunion with addresses. In the afternoon a plaque to the English poet Campbell will be unveiled, and a statue to the French man of science, Duchenne, will be inaugurated. The afternoon will be spent in visiting the town of Boulogne. In the evening those members of the British Association who do not intend to take part in the five days’ excursion will leave for Dover. Sleeping accommodation will be provided in Boulogne for those who intend to visit the towns of Northern France and Belgium on the excursion commencing the following morning (Friday). HANDBOOK. The Local Committee have prepared a special handbook to Dover and the neighbourhood, containing articles on the history and antiquities, the geology, the entomology, the vertebrate fauna, the botany, the climate, the river and tides, the docks and other engineering works, the trade, commerce, and in- dustries. This book is illustrated with maps and plans, some of which contain new work. The information given in the maps and plans and the articles, written by specialists on the subjects they deal with, will, it is hoped, render the work not only useful on the occasion of the British Association’s visit, but also of some permanent value. EXCURSIONS. Wednesday, September 20.—Excursion to Canterbury. The Mayor of Canterbury and the Corporation invite the members, associates and holders of ladies’ tickets to Canterbury in the afternoon, to meet the President and one hundred members of the French Association, Special facilities will be given for visit- ing the various places of industry in the city. The Dean and Chapter will receive the guests at the Cathedral after the Mayor’s reception at the Royal Museum. Thursday, September 21.—(1) Visit of members, associates, and holders of ladies’ tickets to the Association Francaise pour l’Avancement des Sciences at Boulogne. A special steamer will leave Dover at 8.30 a.m. (2) Excursion to Chat- -ham Dockyard and Rochester Cathedral. Limited to 200, (3) Excursion to Wye Agricultural College, to inspect experi- mental farm. Luncheon will be provided by the Principal, Mr. A. D. Hall. Guests limited to eighty. (4) A circular tour through the Weald of Kent, including stoppage at about five NO. 1557, VOL. 60] NATURE 421 towns between Dover and Tunbridge Wells, and extending over two days. Limited to fifty persons. friday, September 22.—There will be a five days’ excursion in France and Belgium, to Abbeville, Amiens, Arras, Brussels, Antwerp, Ghent, and Ostend, at the conclusion of meeting. The excursion will start from Boulogne on Friday morning, September 22, when sleeping accommodation will be provided for those not returning to Dover after the visit to the French Association, CHURCH SERVICES, There will be special services at most of the churches on Sunday, September 17. At St. Mary’s there will be a special service for members of the Association at 11 a.m., when the Rey. Archdeacon Wilson, D.D. (late Headmaster of Clifton) will preach. The railway companies will afford facilities for those wishing to visit Canterbury on Sunday. The Very Rev. Dean Farrar (Vice-President of the Association) has arranged the following special services :-— 10.30 a.m.—The sermon will be preached by the Lord Arch- bishop of Armagh. 3 o'clock p.m.—The sermon will be preached by the Rev. Canon Mason, D.D. The sermon will be followed by an organ recital. 6.30 p.m.—The sermon will be preached by the Very Rev. the Dean. W. H. PENDLEBURY. THE NEW PHILHARMONIC MUSICAL PITCH. p= question of musical pitch has, through the action of some of the leading pianoforte makers, been again introduced into public discussion. That it should end in the general adoption of the French diapason normal hardly admits of a doubt, especially as it is in the United Kingdom only there remain any advocates for the high pitch formerly general. France introduced by law the diapason normal in 1859, and has been gradually followed by Belgium and Italy, Germany and Austria, Russia and the United States of America, leaving this country in musical isolation from which a great effort has yet to be made to bring it into uniformity with other musical countries, so that the note A will be approximately the same here as anywhere else, and not give the impression of a transposition. The difference of vibration number is not so very much; if it were a semitone, it might be easier rectified—at least in concert organs—it may be stated at 3/5, or at most 2/3 of an equal semitone. It is measurement and the important con- sideration of temperature that justify the admission of a subject, at the first aspect merely artistic, into the columns of NATURE. Temperature has as yet met with insufficient consideration. It is hardly alluded to in the “Sensations of Tone” by Helmholtz; it meets with a bare mention only, although somewhat extended in the footnotes of the English translator, the late Dr. A. J. Ellis, who refers (p. 90, second edition) to the experimental work in that direction of Mr. Blaikley. It is well known that the Paris diapason normal is stated as A=87o0 vibrations a second at 15°C. As we reckon by complete vibrations, we take this number at one-half (435), with the temperature by the Fahrenheit thermometer (59°). Although this is a very geod tem- perature for open-air music, as military bands, &c., it is not high enough for operas and concerts taking place in confined spaces with audiences and artificial lighting. The opera and concert orchestras have, therefore, eve.y- where to find their own pitch evolved from the Paris standard to suit an average increase of temperature. If the French Commission had décided upon 20° C. (68° F.), the necessity for an empiric proceeding would have been avoided. They might very well have adopted Scheibler’s suggestion, made in 1834 at Stuttgart, of A=44o. It is known that he worked at a temper- ature of about 70° F. To him we owe the only facile NATURE tonometer, for which his pitch was really A=439'5. It is as well to go back to the protocols of the Congress at Vienna in 1885, which led to the adoption of the French pitch in Austro-Hungary. After a unanimous acceptance of the diapason normal at 15° C. it was pro- posed that, in order to keep the wind instruments in performance to the initial standard vibration number A= 435, the brass and wood wind instruments, and also the organ, should be made for 24° C. (75:2 F.) !—thus in- troducing a second standard to be used concurrently with the first, the necessity attributable to the vibration number being increased automatically by the heating and rarefaction of the air increasing its velocity, and with the orchestral wind instruments by the breath and handling of the players. Mr. Blaikley has shown the velocity of air in pipes is always less than in free air, possibly through the friction of the walls, but in the organ flue pipes it comes so near to free air that the organ may be almost regarded as a_ thermometer. So high a temperature as 24°C. was not left unchal- lenged ; a wiser determination was urged of 20°, which in practice would have proved right. However the great differences likely to arise in average temperatures due to climatic conditions, and to warming and lighting apparatus, as, for instance, gas or electricity, prevented a decision from being arrived at ; so that Vienna is now, -as London was pending the decision of the Philhar- monic Society, using a convenient empiric pitch of about A=440 for concert performances. Ingenious as the Viennese plan in 1885 would have been, it is wiser to have one standard with one note, A, for its expression, and one mean temperature. For brass instrument makers a B flat fork may be used, and to suit the old custom of organ-builders and pianoforte-makers, a C fork ; but in preparing them equal temperament should be rigidly observed. In 1879, at the instance of Mdme. Adelina Patti, the Covent Garden Opera adopted French pitch ; a recent trial in performance satisfied me that it was at A = 440, the temperature being about 70° F., and that there had been no departure from the intention of using the French standard. Little notice has at any time been taken of this important change at the Opera; but when the Queen’s Hall was opened in 1893, Mr. Newman, the manager, and Mr. H. J. Wood, the conductor, lost no time in introducing the diapason normal for all perform- ances for which they were responsible ; the proprietors going to the expense of having the organ, which had just been built at the high pitch, lowered. Mr. Henschel, in his symphony concerts at St. James’s Hall, and in found- ing the Scottish orchestra, speedily followed. But the decisive point for this country was reached when, in July 1896, the Philharmonic Society, the most eminent musical institution in this country, elected to adopt the French diapason normal, and in the following November de- cided to have a standard tuning-fork for their concerts. Having consulted me, the directors accepted my sugges- tion for that pitch that it should be A=439 at 68° F. Forks made for the Society by Valantine and Carr, of Sheffield, were verified by me with the aid of the Scheibler tonometer in the Science Department, South Kensington, and besides the one retained by the Society, accurate copies were presented by the directors to the Science and Art Department, the Society of Arts, the Royal Academy of Music, the Royal College of Music, the Guildhall School, Trinity College, London, and my- self; the last being accessible on all lawful days at Messrs. John Broadwood and Sons, 33 Great Pulteney Street, W. The B flat is stated in the same minute of the Society as=465, the C=522; this last happens to be a just minor third above A=435, an accidental, although useful, coincidence. The vibration number 439 is really the French standard raised to an average performing temperature, theoretically NO. 1557, VOL. 60] [AucusT 31, 1899 by my coefficient of a thousandth part of a complete vibration a second for one degree Fahrenheit, so that for 435 the rise for the next degree is 435. In a variety of ways I have sought an average concert teniperature which I have finally taken at 68°, at which strings, wind, organ and piano should be in tune. According to my coefficient A=435 at 59° should be A=438'93 at 68°. The round number 439 is more convenient. Briefly ex- pressed, my coefficient is *5 per degree for C=soo; nearly, if not quite, the rise in free air. According to Helmholtz, the velocity of sound in dry air is at o° C. 32° F.) 322 metres = 1089°3 feet, say 1090 ; according to Dr. Ellis, at 60° F. the velocity is 1200 feet per second ; with this my coefficient practically agrees. In further justification, I quote the Covent Garden A=44o; the same vibration number for pianos, communicated to me by Herr Seuffert (Bosendorfer’s), Vienna ; the clarinet of Herr Miihlfeld, of Meiningen and Bayreuth, A=439'5, it being understood when warm; a complete trial of all the wind instruments of Mr. Henschel’s orchestra with a piano tuned to A=439 in a room exactly at 68° F. ; and lastly, the crowning triumph of the Lamoureux orchestra from Paris joining forces with the Queen’s Hall orchestra in London this year, the accuracy of pitch in the perform- ance being unassailable, A = 439! I should like to add for organs my trials of the St. James’s Hall organ, at 52° C= 531 and at 72° C= 541, as one of many com- parisons of this nature; and conclude with Prof. Blaserna’s report of a trial at Vienna, 1885, when A = 435 at 15° C., warmed to 30° C., became A = 457°7, equivalent to raising A toa tempered B flat. If a piano were supplied for a concert intended to be French pitch, at the standard fork A = 435, in London or Paris, Berlin or Vienna, it would be too flat for performance. It would be a concession of great importance, which the musical world could not be too grateful for, if the Paris diapason normal were revised for the higher temper- ature, 20 C., and legalised A.D. 1900, for France at A = 439. Our Philharmonic Society has shown the way, the rest of the world would soon follow. Neither the stability of pitch of the tuning-fork nor that of a piano- forte during a concert need be considered. Dr. Ellis gives the flatténing of tuning-fork as 1 in 16,000 per degree Fahrenheit ; Mr. Blaikley and myself in one trial} only of a concert pianoforte, ‘o25 per degree ; but for the short time a concert lasts this must be imperceptible, the elasticity of the music wire having to be reckoned with against the least change of tension. The objections to the A = 439 that have been urged are that wind instrument makers may take it as a start- ing point for a lower temperature than 68°, but not if they are conscientious? We can legislate for this no more than we can for the tendency to exceed the present high pitch, as is shown by our military bands and the majority of the brass bands in this country, in spite of Kneller Hall, which is bound to maintain the old Philkarmonic pitch until the War Office releases the army from it and provides or sanctions French pitch bands. Organ- builders who can work with accurate forks and a ther- mometer will have no difficulty with the French pitch— indeed, nearly all are in favour of it, as are the pianoforte- makers and dealers generally, but there are some who seem to fear their instruments will suffer in brilliancy of effect by the reduction. When, however, we consider the rise in the tension of pianos during the last thirty years, due to improvement in music wire and to a great change of construction, causing in grand pianos a rise in tension equivalent to a minor third in pitch, or more ; and when we reflect that the difference of pitch proposed in tuning to the new Philharmonic is only 3/5 of an equal semitone, we may see in the change more a gain thana loss by a possible increased fulness of tone-quaiity, and above all we shall have uniformity with the rest of the musical world. A. J. HIPKINS. —— —————— —— Aucust 31, 1899] NATURE i) =) RIBBON AND DARK LIGHTNING. M®: ALEX. MORTON, secretary and librarian ef the Royal Society of Tasmania, has sent some photographs of lightning flashes taken by Mr. W. Aiken- head, one of which is here reproduced. The photographs were taken at night with a hand camera. Referring to them, Mr. Aikenhead remarks :—‘“ The thunderstorm was an unusually severe one, and the atmosphere sur- charged with electricity. as evidenced by the frequency and extraordinary vividness of the lightning flashes, whose brilliancy momentarily rendered objects, even at a distance, as clearly discernible as in daylight. The intensity of the ‘triple’ flash—of which I was so for- tunate as to secure a counterfeit—was so great that for some moments I was completely dazzled. I may mention that the thunderstorm lasted fully an hour, and was at its height about g o'clock ; and it was at this period the exposures were made with my camera.” The accompanying picture is interesting on account of the triple flash represented in it, and the dark lines apparently radiating from it. In an article printed in NATURE several years ago (vol. xlil. p. 151, 1890), Mr. Shelford Bidwell described each of these characteristics of photographs of lightning flashes, and gave explan- ations of them. He remarked that in nearly, if not quite, every case where broad ribbon lightning has been photographed, the camera was held in the operator’s hand—a fact which naturally suggests the idea that the widened image of the flash may be due to the movement of the camera during exposure. Though it might be impossible to move the camera appreciably in the brief duration of a single lightning flash, several flashes some- times pass in quick succession over the same path, so that they may appear side by side upon the photograph if the camera is shifted during their occurrence. Moreover, Mr. Bidwell pointed out that lightning sometimes leaves a kind of phosphorescence along its track, and this may fast long enough to produce a photographic picture, even though the flash itself was instantaneous. A photograph of a triple lightning flash reproduced in NATURE of October 13, 1898 (vol. lvili. p. 570) furnishes decisive evidence that a camera can be moved quickly enough to obtain several pictures of a single luminous track of lightning. The three flashes shown in that picture are identical in shape, and it is estimated that they followed one another along the track with a frequency of about 30-35 per second. But while it is certain that some photographs of multiple and ribbon lightning are produced by move- ment of the camera, others represent actual lightning of a broadened or multiple form. Commenting upon some photographs of ribbon lightning obtained by the Rev. J. Stewart-Smith, Prof. Cleveland Abbe remarked in the U.S. Monthly Weather Review of August 1898 that he thought that they were not taken by moving the camera during exposure. He considered that a discharge of lightning was too fleeting to be influenced by the motion of the camera. With artificial oscillatory discharges the time of the discharges and the motion of the sensitive film might be so controlled as to produce the appearance of a ribbon ; but no motion of the camera seemed likely to explain the many details in the ribbon photographs of natural lightning described. Prof. Abbe thought, however, there was one flash on Mr. Stewart-Smith’s plate that had every indication of being certainly an oscillatory dis- charge, showing lines of flow identical with those photo- graphed by Prof. Trowbridge at Cambridge, Massa- chusetts, and fully maintaining his conclusion that the lightning flash is an oscillatory discharge repeated frequently to and fro within the crack in the air that is opened by the first discharge. That lightning flashes can actually present a ribbon- like appearance, and have an appreciable duration, is NO. 1557, VOL. 60] borne out bya letter which was sent to the Royal Society from Buluwayo at the end of 1895, and was printed in NATURE of January 23, 1896 (vol. liii., p.272). The writers state that they were sitting in a room when one of them called attention to a very bright lightning flash. “All of us promptly went to the door, whence we wit- nessed a truly extraordinary sight in the shape of three ribbons of a greenish-white lightning, which hung in the sky, motionless, for what must have been fifteen to twenty seconds. It seemed to be a long way off (in a north-westerly direction), as we heard no report of thunder whatever. There could be no mistake about it —it was as distinct as possible, and it must have lasted fifteen seconds a¢ /eas¢.” With evidence of this kind to consider, the reality of the ribbon appearance cannot be doubted. To obtain more definite information concern- ing this form of lightning and the nature of the electric discharge in an ordinary lightning flash, systematic at- tempts should be made to photograph lightning with cameras having a known rate of movement, and an Photograph of lightning taken at Devonport, Tasmania, by Mr. Aikenhead. arrangement for determining the angular diameter of the ribbon. As to the dark ramified flashes shown upon the ac- companying picture, Mr. A. W. Clayden has shown by experiment that they are due to photographic reversal. If the lens of a camera is covered up immediately a flash has been photographed, the flash comes out bright in the ordinary way in the print ; if, however, the lens is allowed to remain uncovered for a minute or so, thus exposing the plate to the diffused light of the sky or the glare of other flashes, the original flash appears black upon the final print. In the same way, the discharge of an electrical machine can be made to appear dark in a photograph by leaving the lens uncovered for about a minute after the discharge has imprinted itself upon the plate. According to this, the dark ramifications in Mr. Aikenhead’s picture repre- sent a discharge of lightning which occurred before the bright triple flash. The glare of the bright flash and the 424 NATURE [AucusT 31, 1899 diffused light of the sky caused the photographic reversal of the first image. Photography thus gives no support to the view that dark lightning has a real physical existence; and Lord Kelvin’s letter printed in NATURE of August Io (p. 341), together with that by Dr. W. J. Lockyer in last week’s number, show conclusively that when it is visually observed it is an effect due to fatigue of the retina. THE RECENT ERUPTION OF ETNA, psc A. RICCO, Director of the Etna Observatory, informs us that on July 19, at 8 a.m., Mount Etna threw out from its central crater an enormous mass of vapour, stones, lapilli, and cinders, which were lifted to a height of several kilonietres, and afterwards covered all the south-east slope of the volcano as far as Zofferana Etnae (altitude 600 m.), where the roads are covered by neatly a centimetre of volcanic ash. A number of stones struck the dome of the Etna Observatory (which is about a kilometre from the central orifice), so that about thirty holes were made in the iron plates, six millimetres in thickness, which cover this dome ; five of these holes have a diameter of 30 centimetres, and the stones causing them fell into the observatory containing the refractor. Two stones also pierced the floor, and embedded themselves in the basement ; and one broke three steps of the observ- ing chair. Another pierced the wooden base surrounding the foot of the refractor ; fortunately, this and the other apparatus of the observatory received no damage. Two other stones passed through the roofs of the side-rooms. Round the observatory there are about fifty holes, caused by the fall and penetration of the stones in the sandy soil. A heap of straw which was near the stables of the observatory was reduced to ashes, which proves the high temperature of the eruptive materials ; moreover, holes were also burnt in the wooden flooring where it had been pierced by stones. The steam of the eruption condensing in the air gave place to a warm and acid rain in the higher parts of the volcano, and lower down it caused ordinary rain. The column of steam had by nine o’clock spread itself enormously in the sky nearly over Catania (a distance of 30 km.), and caused a marked darkening. By 9.30 the column had disappeared. The eruption was accompanied by no perceptible move- ment of the earth, except a slight shock at the lower end of the Valle del Bove. The instruments at Catania only indicated a very slight oscillation. At the Etna Observ- atory two seismometers showed horizontal and vertical movements. The eruption was also accompanied by detonations, which were heard very slightly as far as Catania. On July 25 there occurred a similar eruption, but of less importance. PROFESSOR BUNSEN, N Wednesday morning, August 16, the illustrious Heidelberg chemist breathed his last, after a long life wholly devoted to the furtherance of science. In April 1881 I communicated to the cclumns of this journal a sketch of the work of him whose death at the ripe age of eighty-eight all lovers of science now have to deplore. We can only now call attention to the magnitude and extent of that work, and lay on the grave of one of the truest and noblest of men the tribute of our admiration and respect. As expressing the position held by Bunsen amongst the standard-bearers of science, I may, perhaps, be forgiven for quoting the opening sentences of what I wrote eighteen years ago, as I cannot find more appro- NO. 1557, VOL. 60] priate words to indicate what all feel who know what his work was. “The value of a life devoted to original scientific work is measured by the new paths and new fields which such work opens out. In this respect the labours of Robert Wilhelm Bunsen stand second to those of no chemist of his time. Outwardly the existence of. such a man, attached, as Bunsen has been from the first, exclusively to his science, seems to glide silently on without causes for excitement or stirring incident. His inward life, how- ever, is on the contrary full of interests and of incidents of even a striking and exciting kind. The discovery of a fact which overthrows or remodels our ideas on a whole branch of science; the experimental proof of a general law hitherto unrecognised ; the employment of a new and happy combination of known facts to effect an invention of general applicability and utility ; these are the peaceful victories of the man of science which may well be thought to outweigh the high-sounding achievements of the more public professions.” In the columns which follow the above will be found a statement of the chief experimental researches which have not only raised Bunsen by the common consent of all who can understand the results of accurate and far- reaching methods to the highest point of scientific honour, but also of those more popular discoveries which have made his name a household word in circles far wider than those of purely scientific appreciation. Now, therefore, it is only necessary to recall the main facts of his life work ; to note, in the first place, that his desire to unravel the secrets of nature was un- alloyed by any attempt to make capital out of any application of his discoveries. “To one man,” he often said, ‘‘comes the duty of discovery, to another that of applying that discovery to practical uses.” Like our great countryman Faraday, Bunsen consistently refused to be drawn away from the paths of purely scientific investigation, and, though too clear-sighted a mind to belittle the importance of the application of scientific discovery to every-day life, rightly judged that to him belonged the undoubtedly higher and nobler work of enlarging the boundaries of knowledge. The next thing to be noted about Bunsen’s work is its originality and its accuracy. It matters not whether we look into his purely chemical investigations, at his chemico-geological researches, or at those—perhaps the most remarkable amongst the many questions he answered —which lie on the borderland of physics and chemistry, in every case we rise from the study not merely feeling that we have to do with a master’s mind and hand, but that each investigation is stamped by an original mode of treatment and by an accuracy of thought and of manipu- lative power which, it is not too much to say, has rarely if ever been equalled. In no instance was this rare combination of mental and manual dexterity more strikingly shown than in his investigation of the compounds of czesium, the rarest of the two alkali metals which he discovered by means of spectrum analysis. In order to prepare the pure salts of this metal, some scores of tons (I write this away from books, and therefore cannot give the exact figures) of Diirkheim mineral water had to be evaporated, and from this residue it was only possible to obtain some five or six grams of the pure chloride. Nevertheless, from this comparatively minute quantity Bunsen suc- ceeded not only in preparing and analysing all the im- portant salts of czesium, but in ascertaining by goniometric methods their exact crystalline form. So that he was able to supply all the information requisite to a complete understanding of the position of this new element and its compounds to those of its well-known relations potassium and sodium. Then look at his gasometric methods. He was the first to attempt anything like exactitude in the measurement of AuvcustT 31, 1899] NATURE 425 gases. And when he had perfected his methods, no im- provements as regards accuracy were forthcoming. Other quicker and, perhaps, more handy processes have since come into vogue; but it was Bunsen who taught men how to handle and to separate and measure gaseous substances. Next take his researches in chemical analytical methodss There we find again that all he touches he adorns. Whether in the delicate and complicated silicate analyses, in blow-pipe work and flame reactions, in volumetric methods, in separations of closely allied metals, such as antimony and arsenic, or those of the cerite earths, we see the same master’s touch. Then his physico-chemical researches, his ice-calorimeter, his photo-chemical investigations, about which I am able to speak with special authority ; his methods of ascertaining the specific gravity of gases by their rates of diffusion, and many other distinct lines of research, all well known and recognised as classic, exhibit the same wonderful power. About his more popularly-known discoveries it is not necessary here to speak, save to say that the Bunsen battery and the Bunsen burner have rendered his name a household word all the world over, whilst his application of spectrum analysis to the investigation of terrestrial matter has done more than all the investigations of past time to increase our knowledge of the chemical composi- tion of the earth’s crust. But this experimental work, great and important as it is, is not the greatest or most important work which he ac- complished. It is asa teacher and as an example that the name of Bunsen is and will be chiefly honoured and re- membered. It is only those who have had the benefit of working under and with him who can fully understand the feelings of affection and respect with which they regard his memory. To those who had the privilege of his intimacy, of whom I can happily lay claim to be one, his friendship will remain as an abiding source of gratification. As an investigator he was great,as a teacher he was greater, as a man and a friend he was greatest. HENRY E. ROSCOE, NOTES. THE Royal Society has received through Mr. Chamberlain the following memorandum by the Governor of the Straits Settlements :-— The Government of the Straits Settlements desires to invite the attention of Radcliffe’s travelling Fellows, and of holders of scholarships for medical and physical research, to the study of the tropical disease called Beri-beri. This disease caused in the hospitals of the Colony 730 deaths in 1896 and 692 in 1897. This Government will be glad to assist any scholar who desires to engage in the scientific investigation of this disease in the Colony by providing him with furnished quarters, rent free, by giving him free access to all the hospitals and facilities for study- ing the cases therein, by defraying the cost of his passage to the Colony, and in any way which may be agreed upon hereafter between the scholar and the undersigned. By Command of the Governor, J. A. SWETTENHAM, Colonial Secretary, S.S. Colonial Secretary’s Office, Singapore, July 20, It may be added that Dr. Hamilton Wright, late of Montreal, has recently been appointed pathologist to the Straits Settle- ments. He will be provided with an adequate laboratory, on the furnishing of which he is now engaged. The opportunities for pathological research will therefore be extremely good. THE eighteenth annual Congress of the Sanitary Institute was opened at Southampton on Tuesday, when about seventeen NO. 1557, VOL. 60] hundred delegates attended. Sir William Preece, K.C.B., the president, delivered his inaugural address, in which he dealt with the principles underlying practical applications of sanitary engineering, Mr. A. H. MILng, hon. secretary of the Liverpool School o1 Tropical Diseases, informs us that in response to a request from Major Ross that workers should be sent out to join him at Sierra Leone, the school is despatching, as an assistant to him, Dr. R. Fielding Ould, of the Liverpool School of Pathology, who has had special experience in private bacteriological research. It isto be hoped that the Government will take the matter in hand, and will help the work of the expedition. WE learn from Scéezce that Dr. A. B. Meyer, Director of the Dresden Museums, is now in the United States on a commis- sion from the Saxon Government to inspect American museums before the new buildings are erected at Dresden. He is accom- panied by Prof. P. Wallot, who is one of the international commission of architects selected to decide on the plans of the University of California in accordance with Mrs, Hearst’s arrangements. A Reuter telegram from Potsdam states that the new observ- atory and the great refractor, recently erected at the Astro- physical Observatory there, were inaugurated on Saturday, August 26, in the presence of the German Emperor. Our photographic readers may be reminded that all entries for the Royal Photographic Society’s forty-fourth annual exhi- bition, to be held at the Gallery of the Royal Society of Painters in Water Colours from September 25 to November 11, close on Wednesday, September 6, at 9 p.m. THE Allahabad Peoneer Maz? states that an Austrian scientific party will visit India towards the latter end of October to observe the display of Leonid meteors which will take place in November. Two observation stations are to be fixed at Delhi, some five miles apart, telephonic communication being main- tained under arrangements made by the Telegraph Department. Dr. A. CANCANT, formerly assistant at the geodynamic observatory at Rocca di Papa, has been selected to succeed Dr. G. Agamennone as assistant in the central office of meteorology and geodynamics at Rome. Dr. Cancani is well known to seismologists for his work in connection with the velocity of earthquake-waves, and for the improvements which he has made in the pendulums designed for recording the undulations from distant earthquakes. REFERENCE has already been made to the fact that the section of the tree under which Dr. Livingstone’s heart was buried, containing the inscription carved by his followers, has been obtained for preservation in the Royal Geographical Society’s collection of relics. The Avitish Central Africa Gazette, published at Zomba, gives the following particulars of the journey to obtain the section:—Mr. Codrington, Deputy Administrator for the British South Africa Chartered Company north of the Zambesi, left Fort Jameson (Mpezeni’s) on April 24, and reached Chitambo on May 9. From the present village of Chitambo he travelled with Chitambo ten miles E.S.E., three miles to the Msumba river or swamp, and then seven miles to the Luwe river. These streams flow into the Lulimula river, and that into the Luapula. Chitambo states that his father was interred under the A/fundu tree close to the spot where Livingstone’s heart was buried. The following measurements were taken of the tree: Round base, 13 feet 5 inches ; round bottom of inscription, 10 feet 1 inch; round top of inscription, 10 feet ; height of bottom of inscription from ground, 4 feet 5 inches, The bark was cut off by Livingstone’s men in order 426 to enable the inscription to be carved, and it has now grown over part of the letter ‘‘E” in Livingstone and over the number ‘3” in 1873. Livingstone’s A/pundu tree was too old to give seeds, so it was not possible for Mr. Cod- rington to bring away any of these. After the tree had been cut down, and the section containing the inscription care- fully removed, a tall iron telegraph pole was erected in the entre of the stump and carefully secured. This, together with the various observations taken, will suffice to mark the exact spot until a suitable monument may be erected. The altitude (by boiling point) at the AZpundu tree was found to be 3877 feet above sea level. Mr. W. WELLMAN and the American members of his polar expedition arrived at Hull on Tuesday from Tromso. In addition to the information published in last week’s NATURE (p. 399) concerning the results of the expedition, the following particulars were given by Mr. Wellman to a representative of Reuter’s Agency :—‘‘ The point at which we turned back was about twenty-five miles north-west of the Freeden Islands, where Dr. Nansen landed in 1895, and north of these islands we saw and took the bearings and photographs of three islands and a large land, none of which had been seen by either Payer or Nansen. We were also able wholly to clear up the mystery of Payers so called Dove glacier, which simply does not exist, as Dr. Nansen had in part shown. In addition to this useful geo- graphical work, greatly augmented by subsequent journeys under Messrs. Baldwin and Harlan, these two gentlemen and Dr. Hoffmann, the naturalist, did some valuable scientific work which will, I feel sure, attract much attention when elaborated and reported in proper form, I still believe it possible to reach the North Pole by Franz Josef Land, but whether or not I shall make another effort in that field I am unable to say.” After Mr. Wellman’s return to headquarters on April 9 Mr. Baldwin again took the field, leaving camp on April 26, accompanied by the four Norwegians, this party having twenty-six" dogs and two sledges, carrying provisions for three weeks, Their object was to examine the unknown region to the eastward of Wilczek Land. They were enabled to chart the entire eastern as well as north coasts of that land. Thirteen miles further east they discovered a large ice-covered island nearly as large as Wilczek Land and extending to 64° E. longitude. Several islands were also discovered during this journey. The newly- discovered land was named Graham Bell Land, after the president of the National Geographical Society of America. Another exploring journey was made by Mr. Harlan, and later a trip by steamer, the result being a fairly complete survey of the unknown and unmapped parts of the archipelago. smaller THE practical application of the Rontgen rays to the needs of medicine and surgery formed the subject of the presidential address recently delivered before the Rontgen Society by Dr. C. M. Moullin. There is no branch of medicine or surgery which does not afford abundant evidence of the improvements which have taken place in the production and utilisation of the Rontgen rays in the course of the past year. Dr. Moullin points out that the fluorescent screen has now reached such a degree of perfection that with suitable apparatus the minutest move- ment of the heart and lungs, and the least change in the action of the diaphragm, can be watched and studied at leisure in the living subject. In short, Dr. Moullin testifies that there is scarcely any change in connection with the lungs and the heart and great vessels which cannot now be seen and photographed, scarcely a disease of the chest or of the organs which it contains concerning which the most valuable information cannot be obtained. To such an extent has the fluorescent screen been improved, and so easy has investigation with it been made, that it is probable that some day the examination of a patient’s chest NO. 1557, VOL. 60] DETER [AucustT 31, 1899 with it will be considered as much a matter of routine and as little to be neglected in all doubtful cases as an examination with the stethoscope is at the present time. Valuable as are the indications given by the ophthalmoscope in obscure diseases of the brain, they are not to be compared with those which can be obtained by systematic and skilled use of the fluorescent screen in diseases of the heart and lungs. THE benefit which surgery has derived from the improvements which have been effected in the use of the Réntgen rays during the past year is, Dr. Moullin states, no less striking than that gained by medicine. As might be expected, the largest pro- portion and the most striking cases have been furnished by the injuries and diseases of bones and joints. With a well-lit fluorescent screen the nature of an injury can be seen at once, and, what is even more valuable, it is no less easy to ascertain whether a fracture is properly set or a dislocation completely reduced. If the screen is of service to physicians in the diagnosis of intra-thoracic disease, the records of the past year have shown by numberless instances that it is no less valuable to surgeons by enabling them to make sure at a glance that the bones are in their proper relative situation without touching the splints or giving the patient a moment’s pain. So far as surgery is con- cerned, Dr. Moullin remarks, nothing illustrates the immense improvement which has been made in radiography in the course of the past year better than the detection of renal calculi. Until this year the instances in which they had been photographed and verified by operation were few and far between. Now, thanks more particularly to the work of Mr. Mackenzie David- son in this direction, the detection of renal calculi can be looked forward to with a fair degree of certainty, and, what is even more valuable, as saving patients from unnecessary operation, the evidence can be trusted equally well when it is negative. In all ordinary cases it may be said that if no calculus is seen there is no calculus there to see. FROM reports in the Agrica/tural Journal, published by the Cape Department of Agriculture, it appears that much success in exterminating locusts by inoculation with the locust disease fungus has been attained in many districts. The fungus is pre- pared and supplied by the Director of the Bacteriological In- stitule, Graham’s Town, at a cost of sixpence per tube to all applicants residing in Cape Colony. One of the reports upon its use states that over a hundred locusts which were inoculated with fungus disease were distributed amongst a swarm, and on the next morning and the following days large numbers of dead ones were in the sand dunes, being killed by the fungus, as microscopical examination and further experiments with the bodies proved. The growth of fungus from the dead locusts produced a fungus more rapid in growth but smaller in size than the Government fungus. In another case, the fungus was mixed in lukewarm water, and young locusts were released after immersion in the liquid. After three days rain fell, and on the afternoon of the fourth day locusts were found in heaps in the bushes about three miles from where they were immersed. Districts in which no such measures are being taken are much more infested with locusts than those where the fungus treatment is adopted. SEVERAL articles and notes upon india-rubber and the india- rubber industry in various parts of the world are contained in Nos. 147-150 of the Budleten of the Royal Gardens, Kew, just published. A paper by Prof. Tilden on the spontaneous con- version of isoprene into caoutchouc is reprinted, and it is pointed out that the result represents a step towards the artificial pro- duction of india-rubber commercially. Prof. Tilden has not yet been able to bring about this change at will. His observations show that the polymerisation proceeds very slowly, occupying several years, and all attempts to hurry it have resulted in the ee ee eae oe ae ~~ AucusT 31, 1899] NATURE 427 production, not of rubber, but of colophene—a thick sticky oil, quite useless for all the purposes to which rubber is applied. The Aulleten publishes correspondence showing how the falling off in the production of rubber at Lagos is due to the reckless way in which the trees have been exhausted. The rubber is collected from the Ire tree (Avch.xza africana), and has been an important source of wealth to the Colony ; but the industry is rapidly decreasing, owing to want of control over the collectors who tap young trees, and destroy rubber forests by over-working. In Madagascar efforts are now being made to establish plant- ations of rubber-producing plants. The island has long been known to furnish a supply of india-rubber to commerce, the rubber being obtained until a few years ago from species of Landolphia—the rubber-vines, which are so widely distributed in tropical Africa. About 1892 another source of rubber was exploited, but unfortunately both the trees and shrubs producing rubber have been ruthlessly destroyed, and it is necessary to take active steps to cultivate rubber plants to preserve the industry. The May and June Avc//ed2 contains correspondence which indicates the actual source of Peruvian india-rubber. According to the information received, the Caucho tree of Peru is a Castilloa. Bulletin, No. 56 (April 1899), of the West Virginia Agri- cultural Experiment Station, Morgantown, consists of a report on investigations to determine the cause of unhealthy conditions of the spruce and pine from 1880-1893. This is one of the admirable series of reports which are now issued regularly in many parts of the United States, in order to cope with the immense destruction wrought by insects in that country, resulting, during the fourteen years mentioned above, ‘‘ in the death and total loss of many hundred thousand dollars’ worth of the finest timber in the State” of Virginia. Ento- mology is no child’s play in the States, and Prof. Hopkins enumerates 197 species of insects, observed by himself as infest- ing the spruce and pine, about half of which are injurious, the remainder being beneficial as parasites of the destroyers, or in- different. These belong to all orders of insects except Orthoptera, and we imagine that a careful search would be able to fill up this gap by the discovery of some Blattidve, at least, under loose bark, or in similar situations. Most of the mischief, however, is done by wood-boring beetles, of which, and of their curious burrows, many illustrations are given, There is also an illustration of a portion of a black spruce tree eight inches in diameter, which had been slightly injured, when a colony of large black ants (Camponotus pennsylvanicus) took possession, and hollowed out the trunk till the heart-wood was completely destroyed, and the tree fell. This report should be of great interest both to entomologists and foresters, for our own conifers are liable to the attacks of a large number of insects congeneric with many of those here mentioned, though others (as for instance Camponotus, just referred to) do not inhabit this country. In the U.S. Monthly Weather Review for May, there is a useful summary of the climatology of the Isthmus of Panama, by Brigadier-General H. J. Abbot. The first Panama Canal Company made daily observations at Colon, Gamboa and Naos during the years 1882-7, from which it is seen that the temper- ature differs very slightly during the year. At Colon the mean of the absolute maximum temperature varies from 89°°6 in February to 91°°9 in October; and the absolute minima from 68°-4 in January and April to 70°*5 in October. At Gamboa the absolute mean maximum was 97°'5 in June, and the minimum 59°°4 in February ; and at Naos these means were respectively 96-3 in June and 66°°7 in March. Throughout the whole Isthmus the rainy season begins with May ; owing to the north- ward advance of the layer of rising air, a diminution takes place in July, in the interior, but is subject to the delay of one month NO. 1557, VOL. 60] on the Pacific side and of two months on the Atlantic side. A second maximum occurs at the end of September in the interior, but at the end of October on the Pacific coast and in the middle of November on the Atlantic coast. Then comes the dry season, which begins everywhere about January 1, and continues for four months. The mean annual rainfall is 120 inches on the Atlantic coast, 93 inches in the interior, and 62 inches on the Pacific coast. Although the rainfall is large, it is com- parable with the amounts registered in the United States near the Gulf of Mexico. The paper contains a number of frag- mentary observations referring to other periods, for which hourly or monthly variations from mean values have been calculated. WE have received from the Observatory of Manila, of which the director is Father J. Algué, S.J., a volume (pp. xvi + 192, 4to) entitled ‘*Las nubes en el Archipiélago Filipino.” The observatory was one of the institutions invited by the Inter- national Meteorological Committee to take part in the special observation of clouds during a year ending May 1897. The volume in question, owing to delay in preparation of the necessary instruments, contains results from June 1, 1896, to July 31, 1897. The work is divided into two parts, giving (1) an account of the principal nephoscopes and theodolites in use, and the results obtained in the Philippine Islands by means of some of them; and (2) an explanation of the methods used in the photogrammetric measurements of the heights and velocities of the clouds, and the valuable results obtained at the Manila Observatory. The volume also contains an interesting account of the importance of the observation of the movements of upper clouds for the purpose of storm prediction. THE ‘‘Eight Queens Problem” is the problem of finding the different ways in which eight queens might be arranged on a chess-board so that no two should be in check of each other ; in other words, the number of ways of arranging eight pieces so that no two shall be in the same row, column, or line parallel to a diagonal. This problem, which has occupied the attention of Nauck, Gauss, Giinther, Glaisher, Rouse Ball, and Pein, forms the subject of a paper by Dr. T. B. Sprague in the Proceedings of the Edinburgh Mathematical Society. There are ninety-two solutions, but these are not all independent, for in general each solution gives rise to four altogether by simply rotating the board, and this number is doubled by taking the reflections of these in a mirror, the exception to this rule being when the pieces are symmetrical about the centre. Mr. Sprague considers the general problem for a board of 2° squares. This problem was reduced to one in determinants by Giinther and Glaisher, thus: if a determinant is constructed in which terms in lines parallel to one diagonal are represented by the same letter, and those in lines parallel to the other have the same suffix, the solutions are the terms of the determinant in which no letter or suffix occurs twice. The solutions for squares with one to ten squares in a side were given by Pein, and the ten-sided square possesses 724 solutions. Mr. Sprague has now given the solutions for an eleven-sided square, which are 2680 in number, but he considers it would be necessary to obtain the co-operation of a number of persons in order to classify the solutions for larger squares. Very little has hitherto been recorded in regard to the life- history of those peculiar North American rodents locally known as Sewellels, and scientifically as Hap/oéonr. It is therefore satisfactory to have a description of the habits and environment of one of the species, from the pen of such an accurate observer as Dr. D. G. Elliot, in the March issue of the Pudlications of the Field Columbian Museum. The Sewellels, which constitute a somewhat isolated family by themselves, are animals of the size of a small rabbit, but with a more beaver-like appearance 428 NATURE [AucustT 31, 1899 and coloration, although short-tailed. The species inhabiting the Olympic Mountains is known to the natives as the ‘* Moun- tain Beaver,” or ‘‘ Farmer,” the latter being the title most commonly employed. Retiring in its habits, it keeps to wet and swampy places in the neighbourhood of small streams, making its burrows in the banks of the latter. Although when in the bushes its movements appear to be exceedingly quick, yet when in the open it is rather slow. These animals obtain their name of ‘‘ Farmer” from their habit of making ‘‘ hay.” They usually excavate their burrows in the vicinity of a certain water-plant, apparently a kind of low-growing water-lily. The stems and leaves of this plant the little rodents cut down in large quantities and convey to the mouths of their burrows, where, after being spread out to dry in the sun, they are finally carried into the interior to be used as food and bedding. Ir the history of ‘‘type specimens,” on which museum curators now set so much store, were written, portions of it would read almost like a romance. A case in point is afforded by Dr. Jentink’s account of the rediscovery of the type of the peculiar Malagasy carnivore Fossa daubentonz, published in Notes of the Leyden Museum for October last. In 1872, Gray, after searching the Paris Museum, came to the conclusion that the type described by Schreber was irretrievably lost. Subsequently, however, an imperfect skull turned up in the Paris Laboratory of Comparative Anatomy, which it was thought might belong to the missing specimen. And now Dr. Jentink has discovered in the Leyden Museum a skin with a cast of the Paris skull placed in it, which is undoubtedly the long-lost specimen, It is stated to have been received from Paris in 1835, and appears to be one of the results of an exchange effected by Temminck and Schlegel, who visited the Paris Museum in that year. In- cidentally Dr. Jentink shows that ‘‘ Fossa” is the proper native name of the animal in question, and that it is not applicable to the Cryptoprocta ferox, of which the Malagasy title is ‘‘ Farassa.” This alteration should accordingly be made in our text-books. In the July and August numbers of the Zoo/ogist, the editor, _Mr. W. L, Distant, gives the first two instalments of what promises to be a very interesting discussion on ‘‘ mimicry.” Till the communication has reached a more advanced stage, it will obviously be impossible to learn the author’s general views on a very difficult and very important subject; but it may be noted that he intends to divide the alleged cases of mimicry into those considered as “‘ demonstrated” and those classed as *“suggested or probable,” after which we may expect a fuller discussion on the whole subject. In the first section of his communication Mr. Distant takes up the case of the Stick- Insects (Phasmzdae), and discusses their bearing on the mimicry theory. These insects, he states, are usually considered as undoubted examples of protective resemblance due to natural selection. If, as has been asserted, they are represented in the Carboniferous, they must be the result of an antecedent evolu- tionary process. Further, the presence of imitative Phasmzdae in the Carboniferous implies the existence of enemies, probably | reptiles, and possibly transitional forms of bird-life. Thus mimicry must be of very ancient origin; whence it is argued that some cases of it in existence without any apparent reason may be due to survival, and are now altogether useless to the animals in which they occur. The alleged protective resem- blance of fishes to their surroundings is, the author suggests, not the true explanation of their colouring, their extraordinary fecundity being, in his opinion, sufficient to override the neces- sity for any such protection. We shall await with interest further instalments of this communication, In the August number of the Zoo/ogist a discussion is being raised as to the manner in which the helpless and shapeless NO. 1557, VOL. 60] new-born young of the kangaroo is transferred to the materna pouch and affixed to the nipple from which it is to derive nutriment. Some have said that it is carried in the paws of its female parent, while one asserts that the transference takes place by the aid of the lips, and that it has been actually witnessed in the Zoological Gardens. This, however, we gather from Mr. E. Bartlett’s communication, is not the case. It ought to be possible to decide the point by actual observation in a menagerie. Tuar the Edinburgh Geological Society, under the presi- dency of Mr. John Horne, is ina flourishing condition is manifest from the record of its Transactzons, of which we have lately received Part 4 of vol. vii. for 1899. Mr. J. G. Goodchild contributes a short and appreciative memoir of the late Prof. Heddle, with a portrait of that distinguished mineralogist. This article is followed by a short paper, which was read before the Society in 1856, by Heddle, and not previously printed ; it deals with the minerals of the Storr, near Portree. There is a useful paper on the subdivisions of the Carboniferous series in Britain and their European equivalents, by Dr. Wheelton Hind, who shows to what extent at present he has been able to subdivide our rocks into paleontological zones. Mr. William Gunn dis- courses on the Lower Carboniferous rocks of England and Scot- land, Mr. Herbert Kynaston contributes notes on the petrology of the Cheviot Hills; and there are various other papers of local interest. A short article by Mr. E. Greenly on the Here- ford earthquake of 1896 might more appropriately have been printed in the Zvansactions of a Welsh or West of England Society, as it deals with the relations of this disturbance to geological structure in the Bangor-Anglesey region. A REPORT on the surface geology and auriferous deposits of South-eastern Quebec has been prepared by Mr. R. Chalmers (Geol. Survey of Canada, Part J, dz. Xep., vol. x.). The author has devoted particular attention to the glacial and other superficial deposits in the St. Lawrence valley, as it is chiefly in these that gold is found in workable quantities. The primary source of the gold is traced to the crystalline schists of Pre- Cambrian or Huronian ages; schists which were invaded by diorites and other intrusive rocks, and which afterwards yielded materials to the basal Cambrian conglomerates and later de- posits. In these Cambrian and Silurian rocks much gold would have been disseminated ina fine state of division. After the consolidation of these rocks, upheaval, crumpling, faulting and metamorphism would seem to have taken place; and Mr. Chalmers thinks that the gold was probably brought up in solutions and concentrated along with silica and the metallic sulphides in faults and fissures, thus forming auriferous veins. Much gold was long afterwards distributed in superficial deposits during pre-Glacial times in ancient river-beds; and these de- posits and the material of old weathered surfaces of the crystal- line rocks have been partially removed and redeposited time after time during the changes of Glacial and post-Glacial times. WE have received the general report on the work carried on by the Geological Survey of India during the year ending March 31, 1899, under the direction of Mr. C. L. Griesbach. Field-work has been carried on in the Raipur district, in South Rewa, and in Western Rajputana ; and after many years’ inter- mission the geological survey of the higher ranges of the Himalayas has been resumed. Trilobites of the family Olentdae have been found in the Upper Haimantas slates, showing that they are probably of Upper Cambrian age. The occurrence of (Nenodtscus and » A 5350, I mm. = 49°6 tenth metres. The authors proceed to describe in minute detail their methods of measurement and reduction, introducing a very ingenious interpolating machine they have devised to draw the reduction curves as accurately as possible. Several illustrations accompany the article, showing the breech-piece of the 40-inch with various spectroscopes in posi- tion, two views of the interpolating machine, and a reproduction of the spectrum of 152 Schjellerup extending from A 4800 to A 6300. With respect to the latter, attention is drawn to the apparent bright line at A 5592. The authors find it is easily photographed with four mznutes’ exposure, while to obtain the continuous spectrum adjoining of equal density takes from 12 to 15 minutes. This they think is in favour of its being a true bright line. From its appearance, they think it probable that whatever substance produces this line must exist in the star’s atmosphere at a level adove that of the carbon or hydrocarbon vapour which produces the heavy absorption-bands. PHOTOMETRY OF THE PLEIADES.—Herren G. Miiller and P. Kempf, of the Potsdam Observatory, have been investigating the brightness of the component stars of the Pleiades group, and the greater part of Astr. Nach. (Bd. 150, Nos. 3587-8) is devoted to their communication. They begin by giving tables showing the values obtained for the magnitudes of the principal stars by previous authorities, including Lindeman, Pickering, and Pritchard, and also an analysis of these values showing the varying discrepancies between the several measures of the same star. Then follows an account of their work of determining the magnitudes of 96 stars of the group, the instrument used being a Zollner photometer in conjunction with telescopes of varying apertures. Full details are given of the preliminary experi- ments made for determining the constants of the instruments, &c., using certain of the stars as standards. THE SysTEM OF Sir1us.—In the Astr. Mach. (Bd 150, No. 3588), Herr H. J. Zwiers, of Leiden, givesa revision of his previously calculated elements for the Sirius system (Asér. Nach., No. 3336), which he has been enabled to make by employing the recent measures of Messrs. Aitken and Hussey, 4.30 NATURE [Aucusr 31, 1899 made at Mount Hamilton during 1898 and 1899. The elements he gives are the following :— System IZ. T =1894'0900 7=46° 1''9 K= —7- 37069 2= 44° 30'°2 (1900) P= 488421 years m—Q2=212° 64 €=0°5875 The mean value of the distance of the companion is given as a=7"'594- CATALOGUE OF ASTRONOMICAL INSTRUMENTS.—Sir Howard Grubb has sent us a revised edition of his catalogue of astro- nomical instruments, observatories, &c., showing the nature of the work turned out from his workshops at Rathmines, Dublin. The quality and performance of these are well known to prac- tical astronomers, the catalogue in its new form will be in- teresting to all from the beautiful illustrations with which it is furnished, showing in a most convincing manner the capa- "bilities of various optical and mechanical contrivances. The frontispiece is a reproduction of a photograph of 4 Argus taken with the astrographic telescope at the Cape Observa- tory. At the end of the volume there are four plates showing ‘‘The solar eclipse of 1898,” ‘‘ A specimen of work done by a photographic doublet of 15 inches aper- ture,” ‘‘The great nebula in Orion,” and ‘‘ The Dumb-bell mebula in Vulpecula’’; the two latter being from negatives taken by Mr. W. E. Wilson with a reflector of 24 inches aperture. THE CAPE OBSERVATORY. "THE annual report of Her Majesty’s Astronomer at the Royal Observatory, Cape of Good Hope, for the year 1898, has recently been published. The following is a short 7ésvmdé of the chief details :— The McClean Telescofe.—The equatorial mounting of this instrument, the generous gift of Mr. F. McClean, F.R.S., reached Table Bay in good order on April 11, 1898. In six weeks all the parts had been mounted and adjusted, the stand, however, requiring considerable modification. The fittings for electrical illumination of the circles, scales, and micrometers had to be made or remodelled at the Cape. The hydraulic motor for rotating the dome arrived on July 4, the hydraulic ram and valves for automatic clock-winding on October 11, and by November 1 all the essentials of the ob- servatory and stand were fitted and in good working order. The raising and lowering of the floor and rotation of the domeare commanded by cords which may be actuated by the observer at ‘the eye-end of the telescope with the utmost ease and delicacy, while the hydraulic clock-winding gear, contrived by Mr. McClean, automatically winds up the clock-weight at short intervals without communicating the slightest vibration to the telescope. The 18-inch visual object-glass has proved to be a very fine one, both its spherical and chromatic corrections being practically perfect, as far as the kinds of flint and crown glass at present procurable in discs of that size will allow. The 24-inch glass has two faults : the marginal images show well-marked coma, and the minimum focus, instead of being near to or more refrangible than Hy, is for rays of refrang- ibility between H8 and Hy. it is understood that Sir Howard Grubb will remedy these defects. The slit spectroscope for line of sight work, made by the Cambridge Scientific Instru- ment Company, was shipped from London on December 21, and the 24-inch glass cannot be returned for alteration until tests have been made with this spectroscope in conjunction with it. he New Transit Circle.—The foundations for the new transit circle have been built, and the observatory, of sheet steel, is constantly expected from Messrs. T. Cooke and Sons, of York. Messrs. Troughton and Simms _ reported that the transit circle itself would probably be ready in March 1899. NO. "1557, WOE: 00] Astronomical Observations.—The work of the /vanszt circle has been chiefly devoted to observations of standard stars for re- duction of the measures of the ‘‘ Catalogue Photographic Plates.” During the year 10,355 meridian transits and 9863 determin- ations of zenith distance have been recorded. With the He/zome‘er systematic observations of the major ex- terior planets have been made, the year’s work including fifty- three measures of Jupiter, forty-four of Saturn, forty-five of Uranus, and seventy-two of Neptune, all during opposition. This instrument has also been employed in the triangulation of twenty-one stars surrounding the South Pole, and for investiga- tion the possibility, first suggested by Dr. Rambaut, of atmo- spheric chromatic dispersion affecting the accuracy of heliometer observations. The seven-znch equatorza/ has been employed for observations of occultations, revision of star-lists, and Codding- ton’s comet ; and the s¢x-znch telescope, in conjunction with a Zollner photometer, for the comparison of photographic and visual magnitudes in areas near the pole and equator of the Milky Way. With the astrographic telescope, 469 plates have been ob- tained, 200 of these being ‘‘revision plates,” as it is pro- posed to repeat the whole series of catalogue plates, in order to bring the epoch at which the plates were taken nearer to that at which the comparison stars were observed on the meridian. Geodetic Survey of South Africa.—The field operations in connection with the geodetic survey of Rhodesia were resumed in May at the close of the rainy season, the early part of the year having been spent in training the observers in the use of the Jaderin base-measuring apparatus, the constants of which were accurately compared with the Cape measuring bars. The difference of longitude between Buluwayo and the Cape Observ- atory was determined by exchange of telegraphic signals on four nights, the astronomical latitude and azimuth being also ob- served. After the selection of a site, a base line of 117 miles in length was measured, and during the year seventeen stations were occupied and measurements taken therefrom. An arrangement for the delimitation of the Anglo-German boundary between British Bechuanaland and German South- west Africa having been approved by both Governments on January 1, Lieutenant Wettstein and Major Laffan, R.E., after some months’ sojourn at the observatory for practice in astronomical observations, commenced operations at Reitfontein (long. 20° E., lat. 26° 47’ S.) on November 19, by determinations of astronomical latitude and azimuth and the selection of stations. The existing triangulation in the Cape Colony on the meridian of 20° E. long. is at present limited to the northern triangles of Sir Thomas Maclear’s arc and to Bosman’s accurate triangula- tion of Bechuanaland from Vryburg to the 20th meridian, and along that meridian from the Orange River to Reitfontein. There thus remains to complete the chain from Cape Agulhas (the southern point of Africa) to Reitfontein, a distance of only 140 miles to be filled in. The triangles for this work have been selected, and are about to be measured with the Repsold theodolite by Mr. Alston. In connection with the survey of Rhodesia, Mr. Rhodes has promised that when he is in a position to commence the ex- tension of the railway from Buluwayo to the Zambesi, he will place at the disposal of Her Majesty’s Astronomer the funds necessary to carry on thearc of meridian from Southern Rhodesia to Lake Tanganyika. Thus there is in prospect the completion of the following valuable geodetic data :— (1) A geodetic are along the meridian of 20° E. long. from Cape Agulhas (lat. 34° 49’ S.) to the parallel of 22° S. lat., perhaps to 18° S. lat., ze. an are of 12” 49’, or possibly of 16° 49’ in length. (2) An arc along the meridian of 30° E. long. from the south of Rhodesia (lat. 22° S.) to the southern extremity of Lake Tanganyika (lat. 8° 40’ S.), an arc of 13° 33’ in length. Both of these important operations ‘will be under the direction of Her Majesty’s Astronomer. It is also hoped that the German Government will carry the latter work along the eastern border of Lake Tanganyika to Uganda, whence the way is now clear for a triangulation along the Nile to Alexandria, z.e. practically along the same meridian as above, 30° E. long. This latter work should for various reasons be commenced at its northern extremity. Longitude of Lake Nyassa.—The longitude of Nkata Bay a ll lg AUGUST 31, 1899] NATURE 431 on Lake Nyassa was determined by exchanges of signals between this station and the Observatory, made by Captain Close, R.E., and Dr. E. Kohlschutter. The adopted value for the longi- tude of the station occupied (which was 5°2s. west of the Bay) was 2h. 17m. 7°6s. E., and thus the previously accepted longitude was about six miles in error. This work was undertaken in connection with the delimitation of the Anglo-German boundary between Lakes Nyassa and Tanganyika. Longitude of Umtali.—Similar operations undertaken by Captain Watherstone, R.E., in connection with the Anglo- Portuguese Barué Delimitation Commission, gave the longitude of Umtali as 2h. rom. 412s. E. Time Service.—The usual distribution of time signals for commercial and navigation purposes has been carried out. PROF. F. OMORI ON EARTHQUAKE-MOTION. “THREE important memoirs have recently been published by Dr. F. Omori, Professor of Seismology at the Imperial University of Tokio.! In the first he describes a form of horizontal pendulum adapted for mechanical registration, a method which, like the Italian seismologists, he prefers on account of its cheapness and the more open diagrams which it provides. The pendulum consists of a thin brass cylinder, filled with lead, and weighing about 14 kg. This is attached to a horizontal tubular strut of iron, which ends in a sharp conical steel point, working in a conical steel socket fixed to the wall of an earthquake-proof house. A fine steel wire connects the heavy-bob with a triangular steel prism, whose knife-edge works in a steel V-groove mounted on a projection from.the upper part of the wall. The vertical distance between the points of suspension and support is 24 metres, the horizontal distance being, as usual, very small. The length of the strut from its pivot to the axis of the cylinder is one metre. The complete period of vibration is at present 28 seconds in one pendulum, and 17 seconds in the other. The record is made by a light pointer, connected at one end with the cylinder and turning about a vertical axis working in a stirrup rigidly connected with the ground. At the end of the longarm is hinged a light triangular writing index, the point of which rests on smoked smooth paper, which is wrapped round a light wooden drum, 942 mm. in circumference, and revolving once an hour. While the Italian seismologists endeavour, as a rule, to render their instru- ments sensitive by using a heavy steady mass, Prof. Omori attains the same end by reducing the friction between the parts of the machine ; for instance, the pressure of the writing index on the smoked paper isonly mgm. Prof. Omori also describes a portable form of the pendulum, in which the dimensions and heavy mass are smaller, and the points of suspension and support are connected with a cast-iron stand. The paper is illustrated by some interesting typical diagrams given by the pendulums of pulsatory oscillations and earthquake disturbances of neighbour- ing and distant origin. It is well known that most earthquakes begin with a pre- liminary tremor, consisting of vibrations whose amplitude is very small and whose period is generally very short. When the origin of the earthquake is distant, the duration of the tremors, as noticed by Prof. Milne and others, increases with the distance of the observing station ; and a similar relation, as Prof Omori points out in his second paper, is evident from an examination of different seismograms obtained in Japan. He shows that the duration of the preliminary tremor does not depend on the magnitude of the disturbed area of the earth- quake, for no difference of this kind is to be seen between the disastrous Mino-Owari earthquake of 1891 and its five strongest after-shocks. He finds, moreover, that, for great earthquakes originating at distances between 100 and 1000 km., the duration increases by 15 seconds for every increase of 100 km. in the distance from the origin. The duration of the tremor being ascertained at two or more stations, it is thus possible to determine the position of the epicentre; and, in two cases 1 (1) “‘ Horizontal pendulums for registering mechanically earthquakes and other earth movements”: Journ. Coll. Sci., Linp. Univ., Tokio, vol. xi. 1899, pp- 121-145; (2) “‘ Note on the preliminary tremor of earthquake- motion ’’: 2ézd., pp. 147-159 ; (3) ‘‘ Earthquake measurementat Miyako” : z5id., pp. 161-195. NO. 1557, VOL. 60] which are given the results agree closely with those obtained from isoseismal lines. Prof. Omori remarks that the approx- imate variation of the duration of the early tremors with the distance from the origin can be explained by assuming the existence of two sets of waves, which, starting simultaneously, are propagated with different velocities. The mean velocities for the Mino-Owari earthquake of 1891 and the Hokkaido earthquake of 1894 are 2°2 km. per sec. for the preliminary tremors and 1°7 km. per sec. for the principal waves. The third paper, written in conjunction with Mr. K. Hirata, is a valuable discussion of the earthquake measurements made at Miyako from June 1896 to June 1898. The observatory, which contains a Gray-Milne seismograph, is situated on a small promontory of palzeozoic rocks (in lat. 39° 38’ N. and long. 141° 59’ E.), and the records may therefore be regarded as good illustrations of earthquake measurements in a rocky district. Of the twenty-five earthquakes which form the principal subjects of the discussion, six originated in the mountainous regions to the west, and the remaining nineteen: under the Pacific Ocean, the point one degree east of Miyako being the most active centre of the earthquakes which disturb. the eastern part of Northern Japan. The authors arrive at the following important conclusions. As a general rule, the dura- tion of an earthquake seems to vary directly as the magnitude of the disturbed area and inversely as the distance of the observing station from the origin. The average duration of the vertical component is about four-fifths that of the horizontal component. The period of the maximum movement, both horizontal and vertical, ranges between 0°53 and 1°7 seconds for slow undulations, and between c*12 ard o'rs second for ripples. The average period of the horizontal slow undu-~ lations is approximately constant in the principal and end. portions of an earthquake, while that of the ripples is slightly greater during the principal portion than during the preliminary tremors and end portion. It is remarkable that the average period of ripples is roughly constant in all the earthquakes here considered, never varying much from one-tenth of a second. The range of the vertical motion was invariably less than that of the corresponding horizontal motion, the maximum vertical motion being on an average one-fifth of the maximum horizontal motion ; and this is true both for ripples and slow- undulations. The direction of the maximum earthquake movement, as a rule, is coincident with the direction of the line joining the observing station to the centre. In two earth- quakes (those of February 7 and April 30, 1897), the angle of emergence can be ascertained as well as the position of the epicentre, and from these data the focal depths are found to be 15 and 9 km. respectively. UNIVERSITY AND EDUCATIONAL INTELLIGENCE Mr. A. W. BRIGHTMORE has been appointed professor of engineering construction and surveying at the Royal Indian Engineering College, Cuoper’s Hill. ALL particulars referring to the technological examinations conducted by the City and Guilds of London Institute, and the regulations for the registration and inspection of classes in technology and manual training, will be found in the officiak ‘*Programine”’ just published by Messrs. Whittaker and Co. The syllabuses of the seventy different subjects, with the list of works of reference in each, and the examination papers set this year, should prove of service both to teachers and students of technology. THE ninth summer meeting of University Extension Students in Oxford terminated on Wednesday, August 24. The meeting was throughout uniformly successful. It was divided, as usual, into two parts, the first part terminating on August 9. The number of visitors to the meeting amounted to about 1000. Of these considerably over 100 came from Germany and the United States, other nationalities being fairly well represented. The historical period selected for study was the nineteenth century from 1837, and the scientific section of the meeting was therefore necessarily occupied with the more important results obtained during that period. The lectures were well attended and excited considerable interest. In Part I., Prof. Gotch gave two lectures on ‘f The physiology of sensation,” Mr. G. C. Bourne two on ‘‘ The growth of the living organism,” and Prof. H. A, 432 NATURE |AucusT 31, 1899 Miers one on ‘‘ The growth of acrystal.” Mr. H. N. Dickson lectured on the ‘‘ Influence ‘of climate,” and Prof. W. J. Sollas on the ‘* Geology of Oxford.” In Part II., considerably more attention was devoted to scientific subjects. Prof. W. J. Sollas conducted a series of geological classes and excursions, and Mr, A. W. Brown gave a course of practical instruction in illus- tration of Mr, G,. C. Bourne’s lectures in Part I. Dr. Farrar gave two lectures on ‘‘ Prehistoric man.” Two of the evening lectures were devoted to science, Dr. A. Ransome, F.R.S., discussing microbes and disease, and Mr. G. J. Burch “Wireless telegraphy.” Both lectures were admirably illustrated, Tue following important announcement is inserted in the new Directory (1899) of the Department of Science and Art :— “The Lords of the Committee of Council on Education have under consideration the assessment of the efficiency of instruc- tion in the elementary stage of science and art subjects by inspection only, It is proposed to discontinue examinations, as a test for the purposes of assessing the grant in that stage, after the year 1900. It is proposed that papers shall continue to be set in that stage for students who may desire to be ex- amined and to possess a certificate of having passed the examination ; but that in those cases a fee should be charged to cover the cost of examination.” The Directory contains a number of new regulations affecting schools and classes con- nected with the Department of Science and Art. The object of most of the changes is evidently to encourage prectical instruction in science. Visits of students to galleries, museums, and other public institutions, or attendance at field classes, may now be registered as attendances for grants. Theoretical mechanics and Section I. of the elementary stage of physio- graphy have been added to the list of subjects in which grants for practical work may be given. The syllabuses of inorganlc chemistry (theoretical) elementary stage and of theoretical and practical metallurgy» have been revised, and slight modifications have been made in connection with the syllabuses of mathematics (Stage I.) and botany. With regard to schools of science, students under twelve years of age are to be excluded from them unless specially allowed by the inspector, and students at such schools are not as a rule to be admitted to the science and art examinations. Suggested laboratory arrangements for practical work in physics and biological subjects are described in the Directory, and should be of service in connection with the construction of small laboratories. SCIENTIFIC SERIAL. THE second part of the Zedéschrift fiir Wissenschaftliche Zoologie for 1899 contains two important contributions to the morphology of Invertebrates. The first, by Dr. P. Obst, discusses the fate of the nucleolus in the development of the ovum of certain Molluscs and Arachnids ; while the second, by Dr. E. Zander, deals with the abdominal bristle-like apparatus of the Hymenoptera. Especial interest attaches to the latter com- munication from the author’s discovery that the first formation of the abdominal appendages and of the accessory sexual organs (gonapophyses) belongs to two distinct periods of development. The first of these are truly embryological, making their appearance during ovular development, whereas the second do not commence till an early larval stage is attained. SOCIETIES AND ACADEMIES. PARIS. Academy of Sciences, August 21.—M. Maurice Lévy in the chair.—The Perpetual Secretary announced to the Academy the loss it had sustained by the deaths of MM. Frankland and Bunsen, Foreign Associates of the Academy.—On the cause of the persistent luminous trains which accompany cer- tain shooting stars, by M. Ch. André. Remarks on an observ- ation by MM. Lagrula and Luizet of one of the Perseids seen on August 12; the luminous streak of the meteor could be seen for twenty minutes, during which time marked changes of form were obvious in the trail of the meteor. — On an infinite continuous group of transformation of contact between right lines and spheres, by M. E. O. Lovett.—A method for NO. 1557, VOL. 60] determining the Newtonian constant, by M. G. K. Burgess. The Cavendish method is modified by supporting the weight carried by the torsion thread in a bath of mercury. In this way it was possible to suspend a mass of lead of two kilograms each on a torsion wire of bronze or platinum of 0705 mm. diameter. The sensibility of this apparatus is very great, a shifting of the large masses (10 kgr. each) through 40° turning the torsion system through about 12°. The chief difficulties would appear to be the necessity of keeping the temperature of the mercury absolutely constant, and the variations introduced by fluctuations in the surface-tension of the mercury.—On the magnetic properties of iron at low temperatures, by M. Georges Claude. The hysteresis and permeability of iron are both practically constant over the temperatuie- range, +25° C. to ~185° C., the permeability at - 185° C. being only 2°5 per cent. less than at 25°C. These results are in agreement with the experiments of Thiessen, carried out at temperatures of ~ 80°, but are in opposition to the results of Dewar and Fleming. — Decomposition of phosphate of manganese by water at o° and 100° C., by M. Georges Viard.—On the persistence of the cardiac contractions in the phenomena of regression in the Tunicates, by M. Antoine Pizon.—On temperature and its variations in free air, from observations in ninety captive balloons, by M. L. Teisserenc de Bort. The temperature at different heights presents in the course of the year variations much more considerable than had been supposed from the observations made in an ordinary balloon. Even as high as 10,000 metres there is a marked tendency to an annual variation of temperature. CONTENTS. Plants and their Environment, By a rata 6) CS2) The Newtonian Potential, By G.H Bcc: sho. Zito) Our Book Shelf :— Aclogue: ‘* Faune de France—Mammiferes.”—R, L. 410 Dunlop: “ Anatomical Diagrams for the use of Art Students 759s se T4EO Taylor : “ Chemistry for Continuation Schools”. . 411 Letters to the Editor:— Blue Ray of Sunrise over Mont Blanc.—Lord Kelvin, G:C.V. OF; RE Res ee 4iL A Fold- Making Apparatus ‘for Lecture ‘Purposes. (Lilustrated.\—Prof.G. A. Lebour. . . 411 Scoring at Rifle Matches.—S. H. Burbury, F. R. S.; A. Mallock. . . 412 Spectrum Series. —Lieut.-Colonel w. Sedgwick . 412 Magnetic ‘‘ Lines of Force.”—E. R. P. 412 Critical Pressure. —A Suggested New Definition. —Dr. Ro Ee ederim ‘ 412 Maternal Devotion of ‘Spiders. —Francis ie Row- botham .. 413 The Cambridge Anthropological Expedition ‘to Torres Straits and Sarawak. By Prof. Alfred C. Haddon, F.R.S. . . : Meer ceo a 5 Why People go to Spas. (Lilustrated.) By Dr. Wilfrid Edgecombe . 416 The Dover Meeting of the British Association. By W.H. Pendlebury .. 420 The New Philharmonic Musical Pitch. By A. J. Hipkins : : 421 Ribbon and Dark ‘Lightning. " (Idlustrateds) BRO Hom ees} The Recent Eruption of Etna : 424 Professor Bunsen. By Sir Henry ‘E. ‘Roscoe, F.R.S2 4.) eee . ees 42 Notes): : PM oe es oy IS Our Astronomical Column: — Astronomical Occurrences in September ..... . 42 Holmes’ Comet 1899d@(1892 III.) . ....... 42 Spectra of Red Stars (Secchi’s lype IV.) ..... 42 Photometrysofithepbleidestmenn: <- \. <<) i emmememinrt 20 The System of Sirius . . . Mare 3 lo ee Catalogue of Astronomical Instruments oe sR - 430 The Cape Observatory . . Piece fo Ugo) Prof. F. Omori on Earthquake Motion Satu 431 University and Educational Intelligence . ee AR Scientific Serial) Sag. | oS PP PEC Rares Tce Gy renbt ick Societies and Academies . 432 _— OTC RE 433 THURSDAY, SEPTEMBER 7, 1899. THE LITTLE NEGROES OF THE EAST. The Negritos: the Distribution of the Negritos in the Philippine Islands and Elsewhere. By A. B. Meyer. Pp. 92. (Dresden: Stengel and Co.) R. A. B. MEYER, the distinguished Director of the Royal Zoological, Anthropological and Ethno- graphical Museum at Dresden, has issued as a separate volume a translation of two chapters, brought up to date, of his sumptuous folio monograph “Die Philippinen : II. Negritos” (1893). The Negritos of the Philippines are a dwarf,! frizzly-haired people with a black or dull copper-coloured skin. The head is on the lower limit of brachycephaly (average index about 80). The fore- head is retreating, the concave nose is broad and flat, the projecting jaw is provided with thick lips and pro- minent teeth. The slender body is almost entirely smooth. They area happy, lively people to whom care seems a stranger, their greatest anxiety being the pro- curing of food, which consists of all things edible— fruits, roots, honey, snakes, &c. When they have pro- vided for their wants they care for no further exertion, and love to lie in laziness and ease. Their intelligence is stated to be of a low type, and they are not able to count above five, Their songs consist of monotonous, endless unison chants. Tattooing is apparently uni- versal, the patterns being quite simple. They are without exception monogamists. There is no doubt that these interesting little people, about whom much more information is greatly needed, are closely allied to the pygmy blacks of the Malay Peninsula and to those of the Andaman Islands. They represent an ancient race of mankind, and thus it is im- portant to trace their present and past geographical dis- tribution. The name of “Aéta,” “Aita,” “Ita,” &c., generally applied to these people, is derived from the Tagal adjective zfa, ztim “black” (Malay, zfam); they were known to the Chinese under the name of “ Hai- tan” at the beginning of the thirteenth century. The headquarters of the Negritos are the island of Luzon and the small islands in its immediate vicinity ; here many have crossed with the Tagals, and constitute a half-bred population called Dumagates. There can be little doubt that they are the true aborigines of the Philippines. It may be taken as certain that Negritos are found, not only in Luzon, but also in Panay, Negros, Cebu, North-east Mindanao, and Palawan, not to men- tion smaller neighbouring islands. It is questionable whether they occur in Guimaras, Bohol, Samar, Mindoro, and the Calamianes. There has been much speculation on slender data con- cerning the distribution of the Eastern pygmy negros, of which, as we have seen, the Semangs and allied tribes of the Malay Peninsula, the Andamanese and the Aétas form distinct groups. De Quatrefages, for example, held that traces of Negritos are found nearly everywhere from 1 Average height for males r442 mm., 4 ft. Sfin.; for females 1385 mm., 4 ft. 64 in. NO. 1558, VOL. 60] | mixed (‘“ Négrito-Papous ”), India to Japan and New Guinea, and that Negritos and Papuans live together in New Guinea, crossed and inter- differing from the true Papuans. Dr. Meyer submits these assertions to a careful criticism, which is a valuable corrective to specious generalisation. Theoretically, one would expect to find Negritos in Borneo ; the only evidence is the account of a similar people given by Captain Brownrigg to Mr. Earl in 1845 of his shipwreck during the previous year on the east coast of Borneo, and a decorated skull described by de Quatrefages and Hamy in “ Crania Ethnica.” The district visited by the Captain has not been properly explored, and till that is done the question must remain in abey- ance. No other white man has seen a Negrito in Borneo, and it is certain that none have been heard of in Sarawak ; Mr. Charles Hose, who probably knows more about the natives of the interior than any one else, disbelieves in their existence. I have myself seen low-caste natives in the interior of the Baram district of Sarawak, whose hair was wavy and almost curly ; the contrast between these and their nearly straight-haired companions could easily lead to exaggeration, but this does not necessarily indi- cate Negrito blood. Dr. Meyer discusses the provenance of the decorated skulls from Borneo in European museums ; at present our information is too meagre for accurate generalisation. There appears to be no evidence that the skull in question came from the “interior of Borneo,” and it is by no means incredible that the skull, or the person when alive, was imported into Borneo ; slaves have probably been imported at different times, and we know that various peoples have migrated into Borneo from all quarters. There is no evidence of Negritos in Celebes, Timor, the Moluccas and Lesser Sunda Islands. The same applies to Java (the Kalangs are not Negritos) ; but in Sumatra and the neighbouring islands there is still some doubt whether such a population once existed. There is less evidence for an early Negrito stock in Formosa, Japan and China. The evidence for the Mergui Archi- pelago is doubtful, and that for the Nicobar Islands is more so. More evidence is required for Annam, Cochin China, and Cambodia. A good deal has been written about the occurrence of a short, dark, frizzly-haired people in India, but of these there is no evidence whatever. Curly hair is character- istic of the “ Dravidian ” peoples, but this is never woolly. Prof. Keane figures! a “ Panyan woman” as a “ Negrito type, India” ; but a reference to the original photograph published by Thurston ? will prove that the hair is dis- tinctly curly, which feature is unfortunately lost in Keane’s reproduction. Thurston* gives the average height of twenty-five Paniyan men as 1°574 m. (5 feet 2 inches), with a cephalic index of 74; these. are not Negritos. The affinities of the Australians, more or less, with the “‘Dravidians ” is now generally accepted, but a Negrito element has not yet been proved for them. Some hold that the Tasmanians belonged to that stock, and in his 1 ‘* Man Past and Present,” 1899, Pl. Il. Fig. 3. 2 Bulletin Madras Govt. Mus., 1897, ii. Pl. X. 2 3 3 Loc. cit., p. 29. 434 recent presidential address to Section F of the Austral- asian Association for the Advancement of Science, “On the Origin of the Aborigines of Tasmania and Australia,” Mr. A. W. Howitt believes that “the Tasmanians were the autochthonous inhabitants of Australia, and that their preservation in Tasmania was due to isolation by the formation of Bass Strait. The occupation of the continent by the Australians who, it may be reasonably held, were in a higher state of culture, must have resulted in the amalgamation of the two races, or by the extirpation of the former inhabitants, so far at least as regards the males.” He also suggests that a later wave of Papuan migration was virtually stopped by Torres Straits. He also puts forward ‘“the following tentative hypothesis : An original Negrito population, as represented by the wild tribes of Malaysia ; a subsequent offshoot represented by the Andamanese and Tasmanians, and another offshoot in a higher state of culture originating the Melanesians.” Whatever Mr. Howitt writes is worthy of the careful -attention of anthropologists, and it would be well to direct future research with this hypothesis well in view. As Garson, Ling Roth and others have expressed the opinion that the Tasmanians were of Negrito origin (using that term in a general sense), it is rather a pity that Dr. Meyer has not discussed this point. Finally Meyer discusses the relationship of the Negritos to the natives of New Guinea ; he, with Micluko-Maclay, asserts the unity of origin of the Negritos and Papuans, and at the same time insists that the Papuans are diversified and show various types. “Does it point te a crossing of different elements, or does it simply reveal the variability of the race? I [Meyer] incline to the latter assumption as the simplest and as provisionally sufficient, particularly as in the still so limited state of our knowledge it will be labour lost to try to resolve a race like the Papuan into its various elements.” This is not the place to enter into a discussion on this difficult problem ; for the present I can only say that I am inclined to adopt the former view. I certainly have not seen or heard-of any trace of Negritos as such, the brachycephals I encountered in New Guinea were no shorter than the dolichocephals, nor had they more Negritic affinities than the latter. Meyer makes the following emphatic statement : “A Negritic race side by side with the Papuan race nobody has been able to discover, just because it does not exist, and it does not exist because the Papuan race, in spite of its variability, is on the one hand a uniform race, and on the other as good as identical with the Negritos.” A careful perusal of Dr. Meyer’s critical study leaves one fact strongly imprinted on the mind, and that is the urgent need for further evidence. There can be no doubt that observation in the field is by far the most important branch of anthropological work at the present time, and all our energies should be employed in this direction. The time is fast approaching when it will be too late. A. C, HADDON. NO. 1558, VOL. 60] WAT ORE [SEPTEMBER 7, 1899 BACTERIA. Bacteria ; especially as they are related to the Economy of Nature, to Industrial Processes, and to the Public Flealth. By George Newman, M.D., F.R.S. (Edin.), D.P.H. (Camb.), &c. Pp. xvi + 351. (London: John Murray, 1899.) HE author in his preface says that the book is ‘‘an attempt, in response to the editor (F. E. Beddard, F.R.S.) of the series (the Progressive Science Series), to set forth a popular statement of our present knowledge of bacteria.” ‘ Popular science,” continues the author, “is a somewhat dangerous quantity with which to deal. On the one hand it may become too popular, on the other too technical. It is difficult to escape the Scylla and Charybdis in such a voyage.” It may be said at the outset that Dr. Newman has accomplished a very difficult task in a manner which does him credit. Nevertheless, it is to be hoped that in future editions the writer will judiciously curtail certain sections and expand others, and will exercise more caution in laying down doctrines which, in some cases, might mislead the lay reader, and which occasionally even show a wrong conception of the present state of our bacteriological knowledge. That a further edition will be called for at no distant date need hardly be doubted, considering the general excellence of the work. The first thirty-eight pages deal with the biology of bacteria. This portion of the book might well be cur- tailed ; it contains little information that is new, and much that is old and contained in every text-book of bacteriology. The second chapter deals with the bacteria in water, and includes much valuable information. It contains a useful reference to B. enteritidis sporogenes (Klein), a virulent anzerobe apparently causally related to diarrhcea. The biological treatment of sewage might usefully have been discussed more fully and in a separate chapter. The statement, “The cultivation beds also have an inimical effect upon infective bacteria. Hence the final effluent is practically germ-free as regards pathogenic organisms,” must be accepted with caution. The chapter on bacteria in the air is well and con- cisely written, but the author quotes an experiment of his own which is a little difficult of comprehension. To quote his own words : “The writer recently obtained some virulent typhoid excrement, and placed it ina shallow glass vessel under a bell-jar, ‘with similar vessels of sterilised milk and of water, all at blood heat. So long as the excrement remained moist, even though it soon lost its more or less fluid consistence, the milk and water remained un- infected. But when the excrement was completely dried it required but a few hours to reveal typhoid bacilli in the more absorptive fluid, milk, and at a later stage the water also showed clear signs of pollution.” Shattock’s interesting experiments are quoted, showing that sewer air does not necessarily exalt the virulence of a strain of lowly virulent diphtheria bacilli. It is to be noted that this does not affect the question of the possi- bility of sewer air depressing the vitality of the individual, and so allowing lowly virulent bacilli, either already present in the throat or subsequently gaining entrance, to develop and display their full power of pathogenicity. The chapter on fermentation is a good one and is . i SEPTEMBER 7, 1899] INABROU RE 435 more in touch with the original scope of the work as outlined by Dr. Newman himself in the preface. More- over, there is much that is suggestive to the mind of the bacteriologist seeking for new avenues of research in a most important and imperfectly explored field. The subject of bacteria in the soil is well dealt with in Chapter v., and the author records some of his own inter- esting experiments on nitrogen-fixing bacteria. Chapters vi., vii. and viii. treat respectively of bacteria in milk, milk products and other foods; the question of immunity and antitoxins; and bacteria and disease. There is much in these chapters which will repay careful perusal. D r. Newman very properly draws attention to Dr. D.S. Davies’ persevering and instructive investigation of - the late epidemic of typhoid fever at Bristol. It is a little difficult to measure the author’s meaning when he says: “Though the typhoid bacillus appears not to have the power of multiplying in milk, it has the faculty of existing and thriving in milk.” Dr. Newman states that the cause of scarlet fever is unknown. Perhaps it would be fairer to say that some bacteriologists consider that the proof that Klein’s strepto- coccus is the causal agent rests on insufficient grounds. The last chapter is devoted to disinfection, and the subject is well treated. The book is rendered attractive with twenty-four good micro-photographs. There are seventy other illustrations ; many of these are, as the author admits, diagrammatic. In a future edition some, at all events, of these might be usefully replaced by micro-photographs. In conclusion, it may be said that Dr. Newman has successfully accomplished a very difficult task. It is true that the author has not altogether fulfilled his original intention of eliminating technical matters, and that exception may be taken to certain statements as being too dogmatic to please the cautious reader and thinker. Yet, judging the book as a whole, it may be said that it is certain to enhance the writer’s reputation, and will surely be welcomed by the numerous readers of the publications of the Progressive Science Series. It is to be hoped that a demand for this volume may speedily call for a second edition. A. C. HOUSTON. OUR BOOK SHELF. Leitfaden der Kartenentwurfslehre. Von Prof. Dr. Karl Zoppritz. Second edition. By Dr. Alois Bludau. Erster Theil. Dée Projektionslehre. (Leipzig : Teubner, 1899.) Dr. BLUDAU, who has devoted much attention to map- projections, and has written some noteworthy papers on the subject, has lately published the first part of his new edition of the well-known work on cartography by Karl Zoéppritz. The book has been thoroughly revised and re- cast ; and the additional matter is so large as to render publication in two parts, issued separately, desirable. The first part deals only with the various projections of portions of the sphere that have from time to time been proposed. Dr. Bludau’s object has been to produce a work which should meet the requirements of the present day, and be of real service to cartographers. With this view those projections which are of practical use are fully described, whilst those that may be termed “ fancy ” projections are only briefly discussed. Every effort has been made to ensure clearness and distinctness, and only those mathematical propositions and formule that are NO. 1558, VOL. 60] Pp. x,+ 178. absolutely requisite are given. Dr. Bludau has success- fully carried out his programme. The book is well written, and will be of great value and assistance to those who are practically engaged in the production of maps. Every important projection is mentioned with its date and the name of its author ; and full use has been made of the researches of Tissot, and the published works of Profs. Fiorini of Bologna, Hammer and others. Dr. Bludau gives a list of the authorities whose writings he has consulted, and it may be noted that it does not include the name of any Englishman. The subject has been much neglected in this country, and nothing of any importance has been published since the papers of Airy and Clarke, and the well-known little book on the construction of maps by Hughes, the last edition of which appeared in 1864. Dr. Bludau gives almost without alteration the useful hints on drawing which appeared in the original “ Leitfaden” of Zéppritz; and there are some tables for the construction of projections. Part 11. is to deal with topography and cartometry, and to con- tain a number of additional tables. | C. W. WILSON. The Dog, its External and Internal Organisation. Edited by A. C. Piesse, M.R.C.V.S. ; with Anatomical Description by W. S. Furneaux. With five plates and text cuts. Pp. 31. (London and Liverpool: G, Philip and Son.) THIS is. an oblong work of 28 pp. of the puzzle-book order, with five plates, the parts of which are cut out and so arranged in super-position that the reader first skins his dog and then works through its skeletal, circulatory, and muscular apparatus and viscera, until a median longitudinal section is reached. The latter is con- spicuous for the delineation 77 szfz of the central nervous system, but the entire peripheral system has been mysteriously overlooked. The first 14 pp. of the text are devoted to a consider- ation of the history of the dog and of the leading breeds, illustrated by six woodcuts, the remaining 14 pp. to a so-called “ Anatomical Description”—in reality an at- tempt at a general 7¢szzé of the anatomy and physiology of the vertebrate organism with especial reference to the dog, the whole concluding with a detailed explanation of the plates, the organs and structures represented being indicated by numbers. The work is of too thin and amateurish a character to merit detailed comment in these pages, but while fairly trustworthy so far as it goes, it is wanting in balance and accuracy of detail ; and in attempting to express scientific facts in non- scientific terms the authors at times lapse into a loose- ness of expression apt to mislead. To define the “Dogs (Canina)” as belonging “to the family of Mammalia,” and to indulge in feebly stated generalities about the structure of. ganglia and the orders of nerve-fibres, to the exclusion of an adequate description of the course and nature of the leading nerve tracts, is but to confuse the mind. We do not know for what class of persons the book is intended. It will be useless to the serious student, and of little avail to the lay reader, as conveying an accurate idea of the most elementary facts. The small modicum of anatomy which it contains, interspersed with passing allusions to habit and to appearances indicative of disease, will doubtless be attractive to some persons, but by those who desire full information, such as can alone be of real service edu- cationally or otherwise, access must be had to well- known authoritative works such as Ellenberger and Baume’s “Anatomie des Hundes.” The volume before us may perhaps do something to encourage a love of the dog and an appreciation of the beautiful in its con- struction, leading thus up to the study of the more directly useful ; and for this reason we regret the more that a bibliographic list of the afore-mentioned authorit- ative treatises should not have been given. Without one the present work fails in its most useful purpose. 436 INC al OMe ah [SEPTEMBER 7, 1899 LETTERS TO THE EDITOR. [The Editor does not hold himself responsible for opinions ex- pressed by hts correspondents. Netther can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for this or any other part of NATURE. No notice ts taken of anonymous communications. } A Hertz Wave Receiver. DURING a visit to Adelaide in December last year, I was asked to suggest some sort of apparatus whereby Hertz wave disturbances might be observed. The result may perhaps be of some interest at the present time. The spark at the oscillator was small, as only a small induction coil was available. From previous experiments made by me, I had discovered that in order to obtain great sensitiveness the distance between the poles of a Branly detector should be as small as possible ; also the amount of current employed should be very small. After many experiments, I devised an apparatusin which only about 1/16 of a milliampere gave excellent results. The apparatus was simple and easily constructed. In Fig. 1, MN are the poles of the permanent magnet of a D’Arsonval galvanometer ; kK, its coil having a resistance of 500 ohms; H, the internal soft iron A Fey 7a, fixed core ; LL, the flat suspension wires ; 1, a rod of ebonite to the side of which a minute Branly receiver is attached. This forms a part of the galvanometer circuit, and moves with the coil through its angle of displacement, the ends aB of the. suspension wires being fixed to the frame (not shown), The circuit included one small dry cell, 0, and a_non- inductive resistance of 16,000 ohms. In order that the Branly receiver C, after being made a conductor by the influence of a Hertz wave, may be restored to its condition of high resistance, it is brought up against a point F, when de- flected (a side view of this is shown in Fig. 2). This point is kept in a state of vibration by means of a jet of water, thus, D Eisa tube furnished with an elastic disc, to which a projection, F, is attached ; a jet is so fixed at E that its dis- charge impinges on the centre of the disc, the jet is fixed to the tube by a bar, QQ, the discharge is affected by the tube asa resonator, and hence F vibrates. The suspended coil, k, is fur- nished with a mirror and a pointer, whereby its movements are easily seen. This form of decohering instrument was used to avoid the evil effects due to electromagnetic vibrators, which act on a receiver if very sensitive. The induction wings were con- NO. 1558, VOL. 60] nected to the apparatus at Aand B. On repeating the experi- ment at home, I found that 1/16 milliampere is by no means the smallest current that might be used ; all that is required is a current sufficient to move the suspended coil. I am informed that the current used in wireless telegraphy is usually about one milliampere ; it is obvious that by increasing the sensitiveness of the galvanometer a more sensitive coherer may be used. By means of a vane, S, moving in liquid the movements of the coil are damped. The cohering substance was an 8 per cent. alloy, | made in the oxyhydrogen flame, and then reduced to filings in the usual way ; it was found to be exceedingly sensitive, much more so than the mechanical mixture of filings of the two metals. I made several attempts to use a sensitive galvanometer for closing the circuit ; the results were unsatisfactory, the closing of the circuit was uncertain, and when it was closed the tendency to stick, due to the contacts, was a source of much trouble. It then occurred to me that the whole difficulty would be obviated by attaching the coherer to the moving axis of the galvanometer coil itself, for by this means the contact is entirely avoided, while the coherer is brought within the range of a constantly vibrating projection which causes immediate decoherence. A vibrating reed was tried as a decoherer, but abandoned owing to the trouble of feeding it with air under pressure. Another form of decohering vibrator was also tried, which consisted of a long tube, part of which was glass ; each end was furnished with a tympan, one of which was placed as F and p, Fig. 2; the other tympan was led into a metal box containing an electromagnetic vibrator, the hammer of which beat upon the tympan remote from the galvanometer. The electromagnet may thus be placed at a great distance from the apparatus, while its impulses are communicated through the columin of air in the tube. Since my return home, I have used the Wehnelt circuit breaker for producing Hertz waves with ordinary oscil- lators ; the effects appear to be perfect, although the space at my disposal, about two miles, is for the most part covered with houses and high buildings. F. J. JeERvis-SMITH. Oxford, August 26, Is Insusceptibility to Vaccine produced by Small-pox ? IF vaccination inhibits, arrests, modifies, or mitigates variola because it is one with variola, if the attenuated virus and local eruption interfere with the more virulent and generalised erup- tion, may not a reciprocal antagonism be expected? If the- minor malady interfere with the major malady, how much more should the major malady, within a reasonable period of years, confer some degree or manner of general constitutional protec- tion in respect of the minor, if not a modification of the local result of vaccination ? If I tnistake not, systematic investigation on this point, on the human subject, has been strangely neglected in England, if not elsewhere. CHARLES G. STUART-MENTEATH. 23 Upper Bedford Place, W.C., August 14. SMALL-POX does leave behind it an insusceptibility to vaccinia. If the writer of the letter will refer to Dr. Monckton Copeman’s article on ‘‘Variola and Vaccinia, their Manifestations and Inter-relations in the Lower Animals: a Comparative Study ” (Journ. of Path..and Bact., vol. il., 1894, p. 408, e¢ seg.), he will find references to the protection conferred by variola against vaccinia. That systematic investigation has not been carried out is probably due to the fact that the subject has so little practical interest. From the point of view of those interested in the general question of immunity, this subject is well worth careful and systematic study. G. Sims WOODHEAD. THE DOVER MEETING OF THE BRITISH addition to pre- ASSOCIATION. iTS the arrangements described viously, an installation of Marconi’s system of wire- less telegraphy will be set up in the Maison Dieu Hall of the Town Hall. There will be constant communica- tion with the South Foreland, the East Goodwin Light- ship and Wimereux-Boulogne. By ‘means of this arrangement visitors will be kept fully informed of the | proceedings of the French Association at Boulogne. SEPTEMBER 7, 1899] NATURE 437 In Section A (Mathematics and Physics) the President’s address is intended to be taken at 10 a.m. on Thursday, September 14. On Friday, September 15, papers con- nected with mathematical physics and electricity will be read. On Saturday, September 16, on the occasion of the French visit, it is hoped that Prof. J. J. Thompson and Prof Oliver Lodge will communicate papers. On Monday, September 18, the section will subdivide into a meteorological and a mathematical section. On Tues- day, Prof. Threlfall will exhibit and describe his gravity metre, and a discussion on platinum thermometry will be opened by Prof. Callendar and Drs. Harker and Chappuis. The President’s address in Section B (Chemistry) will be given on Thursday, September 14, immediately after the address to Section A. It will deal with the assimila- tion of carbon by the higher plants, and will be mainly descriptive of new work carried out during the past two | years in the Jodrell Laboratory at Kew. In addition to papers of a specially technical character several dis- cussions of interest have been arranged for the meeting. On the occasion of the visit of the French Association on the Saturday, there will be a joint meeting of Sections B and K to discuss the question of symbiotic fermentation, both in its chemical and biological aspects. This dis- cussion will be opened by Prof. Marshall Ward; Dr. Calmette and Prof. Armstrong, amongst others, will take Part in it. Prof. Armstrong has undertaken to open a discussion on a subject of importance and interest in organic chem- istry, under the title of ‘‘ Laws of substitution, especially in benzenoid compounds” ; whilst a prominent place in the programme will also be given to inorganic chemistry in adiscussion on “ Atomic Weights,” to which Prof. F. W. Clarke, of Washington, vill communicate a statement of his views. Amongst the special papers already pro- mised, Prof. Dewar hopes to be able to communicate the results of his most recent investigations on the solidifica- tion of hydrogen, and the liquefaction of helium. Prof. Ladenburg, of Breslau, will read a paper on “The de- velopment of chemistry in the last fifteen years,” and Mr. H. J. H. Fenton will give an account of his recent researches on “Oxidation in the presence of iron.” In Section D (Biology) the following papers of general interest to biologists will be read, amongst others: Mr. J. J. Lister will describe a remarkable new type of cal- careous sponge discovered by Dr. Willey during his | | delivered by Mr. Harold Wager, on sexuality of the expedition to New Britain. Mr. J. J. Budgett, who has just returned from the River Gambia, will give an account of the zoological results of his expedition. Messrs. Gamble and Keeble will communicate an account of their experiments on the colour changes of prawns. Prof. Poulton will describe a new series of experiments on the protective value of form and colour in insects. Mr. W. Garstang will give an account of the methods and results of a periodic survey of the plankton and physical con- dition of the English Channel. Dr. C. G. Petersen will describe the plaice culture in the Limfjord (Denmark). Valuable communications on special morphological pro- blems will also be submitted. Mr. Graham Kerr will discuss the origin of the paired limbs of vertebrates ; and Dr. Willey the process of cephalisation in mollusca and vertebrata. In the marine excursion, if weather permits, the plankton collecting apparatus will be demonstrated ; and Dr. Petersen and Mr. Garstang will exhibit their new forms of net for opening and closing under water. In Section E (Geography) the following papers are promised : Presidential address by Sir John Murray on the floor of the ocean; Mr. J. J. Buchanan, F.R.S., on the physical and chemical work of an Antarctic ex- pedition ; Dr. H. O. Forbes, ona visit to Sokotra ; Mr. A. W. Andrews, on the use of lantern slides in geographical education ; Mr. O. H. Howarth, explorations in Oaxaca, NO. 1558, VOL. 60] Mexico; Dr. G. Schott (Homburg) on the oceano- graphical work of the Valdivia Expedition; Mr. H. N. Dickson, on the oceanography and meteorology of the North Atlantic; Mr. H. N. Dickson will also read a paper on the temperature of the sea water round the British Islands ; Sir John Farquharson, on twelve years’ work of the Ordnance Survey ; Mr. Vaughan Cornish, on the sand dunes of Lower Egypt ; Mr. George Murray, F.R.S., on the distribution of plants in the oceans ; Mr. Robert Irvine, on the distribution of nitrogen in the sea ; Mr. C. W. Andrews, on oceanic islands ; Sir John Murray and Mr. F. Pullar, on the bathymetrical survey of the Scottish Lakes ; Mr. W. R. Rickimens, on a journey in Transcaucasia; Dr. H. R. Mill, on the terminology of the forms of ocean floor; and Mr. E. Heawood on the discovery of Australia. In Section H (Anthropology) the President will deliver his address on Thursday morning at eleven, and the re- mainder of the day will probably be devoted to the dis- cussion of reports and papers on physical anthropology. The subject of finger-prints as means of identification will be examined in important papers by Dr. Francis Galton, and Mr. E. R. Henry, who has used the method with success in police work in India. Other anthro- pometric points will be discussed by Dr. J. G. Garson. Mr. J. Gray contributes a paper on the population of East Aberdeenshire ; and Mr. D. McIver on his recent work on the early inhabitants of Egypt. Friday will be devoted to an important series of papers and exhibits arising out of Prof. Haddon’s recent ex- pedition to Torres Straits. Communications are promised from Prof. Haddon himself, and from Dr. Seligmann and Messrs. Ray and Rivers, who took part in the expedition. Some, if not all, of the archeological papers will be taken on Saturday. Monday and Tuesday will be occupied with papers on Ethnography and kindred subjects. Wednes- day will, as usual, be reserved for overflows and late arrivals. Among the reports, that on the education of defective children deserves particular notice, and those on ex- cavations at the lake village of Glastonbury, the Roman site at Silchester, and elsewhere in this country, will afford interesting material for comparison with those of our French visitors. The President’s address in Section K (Botany) will be delivered at 10.300n Thursday, September 14. On Friday afternoon a lecture—of a semi-popular nature—will be fungi. Saturday morning will be given up to a joint discussion with Section B on fermentation, which will be opened by Prof. Marshall Ward. On Saturday after- noon the members of Section K propose to have a botanical excursion to the sand dunes between Deal and Sandwich. The contributions to be made to the Section include papers on fungi by Prof. M. Ward, Prof. Potter, Mr. Wager, Dr. Darbishire and others ; on physiological botany, by Mr. Francis Darwin; on latex of india- rubber, by Mr. Biffen and Mr. Barkin. Prof. Campbell contributes a paper on studies in Araceze; and Mr. Willis deals with the morphology and life-history of the Indo-Ceylonese Podostemacez. Miss Sargant promises a demonstration of vermiform nuclei in the fertilised embryo-sac of Lilium Martagon. Prof. Bower will read a paper dealing with the sporangia of ferns. Prof. Bertrand, of Lille, communicates a paper on Szgz/- laria. Prof. Weiss sends a contribution dealing with Lepidophiotos, and Mr. Seward and Miss Gowan deal with the botany and geology of the maiden-hair tree. There are also other papers ‘expected on fossil botany. Mr. Lloyd Williams will give an account of further work on the Brown Algee. There are also to be contributions to the Section on local botany and on other subjects of general botanical interest. 438 THE FORECAST OF THE MONSOON. HE brief telegrams that have lately been published from India concerning the amount of rainfall have given a very uncertain note. Favourable and unfavour- able accounts have followed in rapid succession, and at the moment of writing it seems doubtful whether to expect a normal amount of precipitation, or to dread a recurrence of one of those calamitous famines, which drain so severely the resources of India, and from the last of which she has barely recovered. In these cir- cumstances, it is of more than usual interest to turn to the official forecast, to see how the causes, which in the opinion of the best-informed meteorologists affect the climate of India, are operating for and against the prospects of a successful harvest. At the outset we meet with a grave disappointment. The Simla authorities distinctly express their inability to make a forecast, on any scientific ground, of two very important factors which affect the agricultural value of the monsoon rainfall. These are the possibility of the occurrence of a protracted break in the rainfall during the months of July and August, even after the season has opened favourably, and of an unusually early termin- ation of the rains in the North and Central Provinces of India and in Bengal. For fifteen years the Meteor- ological Office has deplored the want of the necessary data that would warrant a prediction on these important topics, and there are no signs that the information will be forthcoming at an early date. As a matter of fact, the authorities go little further than an examination of the conditions under which the south-west monsoon currents will arrive on the coasts of the peninsula. It is true that the probable amount of rainfall in the various provinces of India is considered at some length, but it is expressly declared that this “forecast is a statement of probabilities, and not of certainties, and that it is lable to error from the limitation and uncertainty of part of the data on which it is based.” Similar words accompany all the forecasts that prudent men venture to make, and it must be admitted that the continual repetition is wearisome and distressing. Such a caution may be necessary, but if it produces on the mind of an impatient public the impression that little or no advance is being made in meteorology, and _particu- larly Indian meteorology, a great injustice is done toa body of highly-skilled observers, who have not spared themselves to benefit science, to improve the lot of the agriculturist, and to strengthen the hands of the Govern- ment in dealing with a misfortune they are eager to alleviate, but powerless to avert. But it is not difficult to see some of the reasons that compel the staff to halt at the result of this preliminary investigation. Forecasting, as understood in England, and which practically rests on the capacity of the tele- graph to outrun the storm or the weather it announces, would be valueless in India. Away from the coasts and outside shipping interests, there is no necessity for daily forecasting, nor for the study of those ephemeral fluctu- ations which go to make up our weather. On the other hand, the meteorological conditions that result from the movement of enormous masses of the air attract greater scientific attention, owing to their periodic character and the effect likely to be produced on agriculture and the well-being of large masses of the population. It would be wrong, however, to forget that in late years, and mainly under the energetic direction of Mr: Eliot, barometric variations, however small in amount, have been studied with good effect, and have revealed the probable existence of cyclical variations which can have 1 ‘Memorandum on the Snowfall in the Mountain Districts bordering Northern India, and the Abnormal Features of the Weather in India: with a Forecast of the S.-W. Monsoon Rains of 1899.” By John Eliot, Meteor- ological Reporter to the Government of India, and Director-General of Observatories in India. (Simla: June 1899.) NO. 1558, VOL. 60] NATURE [SEPTEMBER 7, 1899 considerable influence in promoting or checking the general oscillatory motion of the air across the equator, to which motion the south-west and north-east monsoon winds are mainly due. But in the forecast before us, though the variations of pressure from the normal, and the effect.such fluctuations have on the local weather existing in India immediately preceding the advance of the monsoon, are treated as a factor in the problem, two other conditions have naturally great weight. These are the amount and time of occur- rence of the snowfall in the mountain districts adjacent to Northern India, and the behaviour of the south-east trades in the preceding season, as investigated at Seychelles, Mauritius, the Cape of Good Hope, and the logs of ships passing over the area affected. Such latter information is of necessity incomplete, but is likely to be of great importance in proportion as it covers a larger area, for the greater the district brought under review, the greater the probability of tracing the true physical cause on which important variations rest. It may not be out of place, as showing the wide extent over which meteorological phenomena extend themselves, and the consequent necessity for the examination of all remote causes to which they may be traced, to recall the ap- parent connection existing between the barometric oscil- lations in the Indo-Malayan region on the one hand, and Russia and Siberia on the other. Further, we have some evidence of connection between the south-east rains of South Africa and the amount of the rainfall at the time of the summer monsoon, while the overflow of the Nile seems to participate in similar periodic variations. Such general disturbance tends to point to a common cause, and it is gratifying to know that the possibility of the connection has been pointed out by the Indian meteor- ological officers, who are fully alive to the importance of discovering the origin of these effects, which demon- strate themselves periodically. In basing the forecast on more or less local appearances, we seem to recognise the weak point in long-period forecasting. Weare in the position of a physician who deals with the symptoms rather than the origin of a disease. This difficulty of trusting to appearances may be illus- trated in many ways. For instance, how are we going to estimate the relative importance of the two operating factors we have mentioned above, the snowfall on the Himalayas and the behaviour of the south-east trades ? And how are we going to act if we find the indications from the two sources discordant? Some time since we believe that the snowfall was regarded as the one im- portant item in the making up of the forecast. Scanty rain was anticipated as the consequence of heavy snow, but greater experience has somewhat discredited the notion. Late snow in April or May, or the cause which produces the late snowfall, no doubt does exercise very considerable influence locally on the distribution of the monsoon winds ; but when we have to deal (as already pointed out) with the effects produced by the circulation of an atmosphere covering an entire hemisphere, such local results play but an insignificant part. Nevertheless, we find Mr. Eliot, who doubtless is glad to avail himself of every source of information, carefully tabulating the time and amount of the snowfall from Afghanistan on the West to Assam in the East. But, in drawing his con- clusion, he does not leave out of sight the local character of the indication, and a distinction is drawn between the conditions that should follow the reports from Western India and those received from the Eastern Himalayas. In the former case, the signs point to an early and strong monsoon with beneficial results to the utmost limits of the Punjab. The conclusions to be drawn from the ac- counts from the eastern portion are more uncertain both on account of deficiency in the data received and greater doubt in the interpretation of the sign, but it is expected that the rainfall in North-east India will be diminished, SEPTEMBER 7, 1899 | NAT ORE 439 while heavier rain will be prevalent in the north-west. | It will be interesting to compare this prediction with actual results; but at present we are more concerned to point out the care that .s taken in preparing the fore- cast, the difficulty in the collection of exact data, and the manful determination to make the best use of all available sources. This scrupulous care is well illustrated in the second class of information incorporated into the weather pre- diction, and which rests on the abnormal features of the recent meteorology of India. To discuss these with any prospect of success, it is first necessary to determine correct normals. The work that this involves can only be appreciated by those who have been actually concerned in a similar inquiry, but it is a method of investigation into which Mr. Eliot and his predecessor, Mr. Blandford, have thrown themselves with signal success. The volumes of the Indian Meteorological Memoirs bear witness to the ability and zeal with which the work has been carried on throughout some twenty-five selected observatories. We may well express the hope that so much work is now yielding abundant fruit. THE PRESENT POSITION OF THE INVES- TIGATION OF THE MALARIAL PARASITE. “HE ~+éle played by the mosquito as a carrying agent of the malarial parasite from man to man seems to be restricted to one genus, the Anopheles. Major Ross, of the Liverpool School of Tropical Diseases, in a telegram from Sierra Leone, announces the fact that he has found the Anopheles there, and that it may be the intermediary host of the quartan malarial fever. Many observers in different countries, noticing the fact that malaria is most prevalent at the most active period of mosquito life, have attributed malaria to the agency of this insect. Dr. Patrick Manson, in 1894, first brought the subject forward in England, and, acting on his suggestion and advice, Major Ross undertook an investigation in India. In 1897, by using.two species of Anopheles, Ross traced the malarial parasite into the wall of the stomach of the mosquito after it had fed on patients whose blood contained the crescentic gametocytes ; the next year he succeeded in tracing the complete life-history of the proteosoma Grassit Labbé of sparrows, and showed that its intermediary host was one particular kind of mosquito, the Culex pipiens. The gametocytes contained in the red blood corpuscles of the vertebrate host pass with the blood into the stomach of the mosquito, and passing through the stomach-wall bulge into the body-cavity ; here a sexual process takes place, zygotoblasts are eventually formed, which pass into the insects’ blood, and finally find their way into the salivary gland and to the duct leading from this to the extremity of the stylet; from here they escape into the blood of the vertebrate host when the insect bites. A full account of the process is given by Ross in NATURE of August 3. Following on these results, Grassi in Italy attacked the problem from another point of view ; he studied the mosquitoes prevalent in the different parts of the country where malaria occurs. The results were interesting. He found there was no indigenous malaria where the Culex pipiens was common, but it did occur where the large mosquito Anopheles was found. Bignami and Bastianelli, who had been trying unsuc- cessfully to infect a man by allowing mosquitoes to bite him, attributing their want of success to the use of the wrong kind of mosquito, and, acting on the observations of Grassi, tried again with some mosquitoes imported from a malarious district. This time they succeeded in infect- ing the man with malaria of the same type that prevailed | in the district from which the mosquitoes came. More- | NO. 1558, VOL. 60] over, they have shown that the development of the human form of parasite in the body of Anopheles is identical with the development of the proteosoma of birds in Cz/ex pipiens, as observed by Ross. According to these observers, the species Azopheles claviger is the most common intermediary host of the parasite of malaria in Italy, the tertian and summer- autumn types. It is evident that the next step in the study of malaria should be to hunt for the different species of Anopheles and see if these are the intermediary hosts of the different types of malaria throughout the world, and what particular species is most concerned in transferring the parasite from man to man. Grassi has done this for Italy, and now we hear that Ross has found a species of Anopheles to be concerned in the transference of quartan fever ; thus all the types of malarial fever are now re- ferred to the Anopheles as their intermediary host. His full report on return from Africa will be read with interest. Whether the Anopheles can be extirpated from a locality, and by what means, will be the problem for scientific workers resident abroad to settle ; fortunately they seem to be confined to small areas, so the suggestion of Ross to draw off the water from stagnant pools may not be so hopeless a task as it would at first appear. NOTES. THE following men of science have been elected fellows of the Reale Accademia dei Lincei. As ordinary fellows: for mathe- matics, P. Tardy, G. Veronese; for mechanical science, G. Favero, G. Colombo, V. Volterra ; for agricultural science, A. Targioni-Tozzetti. As corresponding fellows: for mathematics, G. Ricci; for mechanics, G. A. Maggi ; for physics, G. Grassi, A. Battelli; for crystallography and mineralogy, A. D’Achiardi ; for botany, F. Delpino ; for agriculture, A. Borzi; for patho- logy, E. Marchiafava. As foreign fellows: for mathematics, G. Mittag-Leffler, J. Weingarten; for physics, E. Mascart, W. Kohlrausch ; for chemistry, Ludwig Mond, E. Fischer ; for crys- tallography and mineralogy, C. Klein, F. Fouque, F. Zirkel ; for geology and paleontology, O. Torell, A. De Lapparent, R. Lepsius ; for botany, W. Pfeffer; for zoology and morphology, E. Haeckel, E. van Beneden ; for physiology, E. Pfliiger, E. Hering. THE Berlin correspondent of the Z%mes reports that the Imperial Government has ordered Prof. Kossel, of the Board of Health, to proceed to Lisbon and Oporto to study the plague and the methods adopted to combat it. Prof. Kossel will be accompanied by Prof. Frosch, of the Berlin Institute, for the Study of Infectious Diseases, who is being despatched on the same mission by the Prussian Government. Drs. Calmette and Salinbeni are already investigating the outbreak, and will report upon it to the Paris Pasteur Institute. PRINCE KROPOTKIN sends us a note which suggests that the movements of sea-gulls along the British coasts may indi- cate forthcoming weather changes. On Saturday, August 26, while off Broadstairs, he noticed several flocks of gulls flying along the coast towards Dover. The wind was then blowing from the north-east, as it had been doing throughout August, and there was little indication of a change; but an old fisher- man remarked that the gulls which had stayed on the coast at Margate and to the west of it were moving to the south coast to meet a south-west wind, which was sure to come. As is known, the change occurred on the following day, and the wind veered round to the south-west.° In connection with this ob- servation, it is worth remark that Mr. Inwards, in his ‘* Weather Lore,” says: ‘‘ The arrival of sea-gulls from the Solway Firth to Holywood, Dumfriesshire, is generally followed by a high wind and heavy rain from the south-west.” 440 NATURE [SEPTEMBER 7, 1899 THE death is announced of M. Henri Lévéque de Vilmorin, first vice-president of the Paris Societé d’Horticulture. and officer of the Legion of Honour. Tue tenth annual general meeting of the Institution of Mining Engineers will be held at Sheffield on September 19-21, under the presidency of Mr. J. A. Longden. Among the sub- jects of papers to be read or taken as read are :—Instantaneous outbursts of fire-damp and coal at Broad Oak Colliery, by Mr. John Gerrard; Castleton: history, geology, minerals and mining, by Mr. A. H. Stokes; the Peak Cavern, by the Rev. J. M. Mello; the mining districts near Kamloops Lake, British Columbia, by Mr. G. F. Monckton; the Devonian iron- ores of Asturias, Spain, by Mr. J. A. Jones; alternating cur- rents and their possible applications to mining (Part i.), by Mr. Sydney F. Walker. A TEACHER of science with a successful career before him has been lost by the death of Mr. O. G. Jones, who was killed in an accident on the Dent Blanche on August 30. Mr. Jones was appointed to the post of physics master in the City of London School in 1892, when a science side was being organ- ised. He received his training at the Finsbury Technical Col- lege and at the Central Technical College, South Kensington, at both of which institutions he held scholarships. He was a B.Sc. of the University of London, where he took first class honours in physics. He possessed high qualities as a teacher, and his sad death will be much regretted. Tue New York Nation publishes a few particulars referring to the Danish northern-lights expedition which has just left Cupen- hagen for Iceland. The headquarters will be at Akureyri, a prettily situated little town on Iceland’s northern coast. The expedition has been for several months under preparation, and its members have been carefully practised in the use of the instruments, all of the latest construction, which it carries with it. While the headquarters will remain at Akureyri, an auxiliary station will be established on a high hill not far away, and the two stations will be connected both by telephone and by an optical telegraph. The Director of the Danish Meteor- ological Office, Dr. Adam Paulsen, is at the head of the ex- pedition. He will test his own published theories on the aurora, as well as others advanced by various investigators. Among the instruments to be used are photographic ones, and others of a novel character for the measurement of aerial elec- tricity. Dr. La Cour and Dr. Jantzen are the two chief assis- tants to Dr. Paulsen, while Count Harold Moltke is attached to the party as its artist. The expedition will return in May 1900. FRoM Schwaz in Tirol to Gloggnitz in Lower Austria the southern boundary of the northern Dolomites and the central zone of the Eastern Alps is marked by a distinct depression, corresponding to a band of paliozoic schists, and evidently produced by denudation. This depression may have been a longitudinal valley, perhaps even in Tertiary times, but it is now drained by five channels which have been eroded across the whole of the northern Dolomites, the valleys of the Inn, the Lake Chiem Ache, the Saalach, the Salzach, and the Enns. In a short but valuable paper, contributed to the current number of the Mztthez/ungen of the Vienna Geographical Society, Prof. C. Diener discusses the relation of each of these valleys to the structure of the rocks through which it has been cut. He finds that in their present form all five are simply results of the erosive action of running water, and their position is practically in- | dependent of the complex tectonic structure of the region. THE scientific aspects of the question of musical pitch were described in last week’s NATURE by Mr. A. J. Hipkins, A book has now been published containing letters, articles, and comments which have appeared in the press with reference to NO. 1558, VOL. 60] the proposal to adopt the low pitch throughout the pianoforte trade, The following agreement has been signed by the leaders of the pitch movement in the pianoforte trade :—‘‘ The vexed question of a suitable pitch for pianofortes should be settled, and believing that the time has arrived when it can be done effec- tually, we, the undersigned, after due deliberation, have de- cided to adopt the Paris diapason normal, but with the allow- ance for a higher temperature in orchestral performance, accepted since 1896 by the Philharmonic Society—namely, A 439 (C 522) at 68° Fahrenheit. From September 1, 1899, we intend to adopt this pitch as a standard for pianofortes both for retail and wholesale purposes, and will regard the’late Phil- harmonic pitch A 454 (C 540) when required, as an exception, and not, as has been for many years in this country, the rule.” IN commemoration of the centenary of the discovery of the galvanic pile, and in connection with the International Ex- position at Como, a statue of Volta has been erected on the Piazza Volta, by public subscription. The accompanying view , of this monument to the pioneer of electrical science is given in Za Nature. Upon the pedestal! of the statue the following words appear :— | OMAGIO | DEI TELEGRAFISTI D’OGNI NAZIONE | NEL DELL’ INVENZIONE | DELLA PILA | MDCCCXCIX. PRIMO CENTENARIO | As already announced, a National Electrical Congress will be | held at Como, in connection with the Volta centenary celebra- —_- woo SEPTEMBER 7, 1899} NATURE 441 tions, on September 18-23. The congress is being organised by the Associazione Elettrotecnica Italiana and the Societa Italiana di Fisica, and the leading foreign scientific authorities have been invited to attend. THE report of the Director of the Botanical Survey of India, for the year 1898-99, shows that every advantage has been taken of the funds placed ‘at the disposal of the survey for exploration in Burma, Assam and Bengal. A report by Mr. J. F. Duthie, Director of the Botanical Department of Northern India, states that the two parties of plant collectors who left Saharanpur in March 1898 to collect botanical specimens in the forest tracts of the Rohilkhand, Northern Oudh and Gorakhpur districts, collected between them about 1000 species ; and also seeds of a large number of trees and shrubs for sowing in the Saharanpur Garden The collections include several very inter- esting plants, for many of them had not been previously recorded for that part of India, whilst some had not been collected since they were originally discovered by Buchanan-Hamilton and others many years ago. : A BLUE-BOOK just issued, on the number of persons em- ployed, and accidents in mines and quarries in the United Kingdom in 1898 contains several noteworthy points. During the year, 990 separate fatal accidents occurred in and about the mines and quarries, causing the loss of 1075 lives. Compared with the previous year, there was a decrease of twenty-five in the number of fatal accidents and a decrease of twenty-seven in the number of lives lost. When these numbers are considered in relation to the number of persons engaged ‘in the mining industry, it is found that the death-rate in 1898 was the lowest hitherto recorded, viz. 1°28 per thousand as compared with 1°49 for the preceding five years.. The improvement commenced in 1895, and has continued steadily down to the present time. It is pointed out that the use of naked lights—always the principal source of danger—is responsible for 147 out of the 163 ex- plosions which occurred, and for sixteen of the twenty-seven deaths. In one of the worst explosions in 1898, it was con- clusively proved that the explosion was one of coal-dust alone, and that it was caused by a shot of gunpowder illegally, fired in a place which was very hot. and dusty. As usual, gunpowder caused far more accidents than any other explosive, and nitro- glycerine compounds were responsible for more accidents than nitrate of ammonia compounds. Tue Physical Atlas which has been for about ten years in preparation at the Edinburgh Geographical Institute, under the direction of Mr. J. G. Bartholomew, will be the most compre- hensive of its kind ever attempted. A draft prospectus just issued shows that the work will comprise seven volumes and more than two hundred plates. The subjects of these volumes will be geology ; orography, hydrography, and oceanography ; meteorology ; botany ; zoology ; ethnography and demography ; general cosmography and terrestrial magnetism, Berghaus’s ‘*Physikalischer Atlas” has been used as the basis of the undertaking ; but the present work is much more extensive, and comprises entirely new and original material. Mr. Bartholo- mew’s aim has been to produce a cartographic unification of natural science at the present time, and neither pains nor ex- pense have been spared to make the Atlas a standard one to which men of science may turn with confidence. The meteor- ology section, with over 400 maps on thirty-four plates, will shortly be published. AMONG the recent publications of the Deutsche Seewarte we would draw attention to a valuable discussion by Dr. W. K6ppen, in vol. xxi. of Aus dem Archiv, upon recent deter- minations of the relation between wind velocity and Beaufort’s wind-force scale (0-12). The relatively great expense of NO. 1558, VOL. 6c] anemometers, and the difficulty of obtaining a good exposure for them, are obstacles to their general use, while the employ- ment of the Beaufort scale is necessarily continued at the great majority of observing stations, and at sea. It is therefore important to determine satisfactorily the relation between wind velocity and force. The first serious attempt at this determin- ation was made by Mr. R. H. Scott, in 1875, and the values then obtained still appear in text-books and instructions, although it is now admitted that the instrumental factor Bhs which had hitherto been generally used for the conversion of the anemometrical records into miles per hour, is consider- ably too high. Since that time experiments have been made, notably by Koppen, Sprung, Mohn, Dines, Curtis and others, the general result of which has been to show that the factor in question should be reduced to about 2:2. This result is confirmed by Dr. Koppen’s recent investigation, and we under- stand that, as a result of his inquiries, anemometrical records’ in ail the publications of the Seewarte will in future be reduced to real velocities by this smaller factor. We recom- mend the careful perusal of Dr. Koppen’s paper to all meteorologists. WE have received from the Secretary to the British Associ- ation Committee on Zoological and Botanical Publication a notice to the effect that at the Bristol meeting of the Associatiom the committee was reappointed, with the Rev. T. R. R. Stebbing as chairman, in succession‘to the late Sir W. H. Flower, and with the addition of Messrs. B. D. Jackson and A. C- Seward as representatives of Botany. It is now proposed to: deal with botanical publications ; and it is believed that the principles and proposals of the 1897 report will apply with equal force to botanical papers. It is hoped that they may be interpreted in that spirit. It will be well to remind our readers that the recommendations are as follows, viz. :—(1) ‘‘That each part of a serial publication should have the date of actual publication, as near as may be, printed on the wrapper, and, when possible, on the last sheet sent to press. (2) That authors’ separate copies should be issued with the original pagination and plate-numbers clearly indicated on each page and plate, and with a reference to the original place of public- ation. (3) That authors’ separate copies should not be dis- tributed privately before the paper has been published in the regular manner. (4) That it is desirable to express the subject of one’s paper in its title, while keeping the title as concise as possible. (5) That new species should be properly diagnosed, and figured when possible. (6) That new names should not be proposed in irrelevant footnotes or anonymous paragraphs. (7) That references to previous publications should be made fully and correctly if possible, in accordance with one of the recognised sets of rules for quotation, such as that recently adopted by the French Zoological Society.” AN account of the electric welding of tram-rail joints in the city of Buffalo, U.S.A., is given in the Zlectrical Review of August 25. This process of rail welding has been greatly improved, and the results now obtained are seemingly all that can be desired. In Buffalo the bar used for welding is. 1 x 3x8, and this joining of steel to steel, and the increased carrying capacity owing to the bars at the joints, results in a joint being a place of least resistance. The plant in operation for the purpose of welding consists of five cars. One of these is a sand-blast car which runs in advance of the welding car, and prepares the joint. The other cars are the welding car, the transformer car, the motor and booster car, and a car that follows in the rear to smooth any rough places about the joint. After the welding bars are placed over the joint the jaws of the welder are applied to them, anda pressure of about 1400 Ibs. applied by means of a hydraulic jack connected to the upper 442 end. The current is then turned on, and the metal becomes brighter and brighter until the weld is completed, after which the current is turned off and the pressure increased to about thirty-five tons. While under this pressure the weld is allowed to cool, after which the car is moved back about six inches and the jaws applied to the other end of the bar, where the process is repeated. The other end is treated in the same manner. In other words, the centre weld is made first, and ther the end welds. Artificial means of cooling are used, and as the bars cool they exert a powerful influence in bringing the rail ends close, so as to make a tight joint. The current for the oper- ation of the plant is taken from the regular trolley wire service. It would be expected, from considerations of the action of heat upon metals, that rails welded in this way would buckle when they experienced a considerable rise of temperature, or snap when the temperature was very low, but, asa matter of fact, welded rails neither buckle nor break. By applying immense pressure to the material during welding, the length of a con- tinuous rail made by this process is said to have no limit except that of the line itself. Dr. FRANz Boas has made a mathematical study (Amerzcan Anthropologist, N.S., i. p. 448) of the biological significance of the cephalic index on the lines suggested by Mr. Francis Galton, and fully developed by Prof. Karl Pearson. His conclusion is that while the cephalic index is a convenient practical expression of the form of the head, it does not express any important anatomical relation. On the other hand, the relation between capacity and head diameters is found to be of fundamental im- portance, and among these the relation between the transverse diameter and capacity is most significant. Since in measure- ments on the living we are unable to measure capacity of the head, it is necessary to find a substitute. It would seem that circumferences are the most available means for judging cranial size. Therefore such circumferences should be included in all anthropometrical schedules designed to investigate racial characters. From the Field Columbian Museum we have received Nos. 3 to 6 of the first volume of its ‘‘ Geological Series” (Chicago, 1899). No. 3 treats of the ores of the South American Re- public of Colombia, the specimens being described by Mr. H. W. Nichols, from a collection made by Sefior F. Pereira Gamba. The ores were obtained from the mountainous western portion of Colombia, in which the Andes entering from the south divides into three chains known as the eastern, central and western Cordilleras. Gold was first mined by Europeans in Colombia in 1537, and during the sixteenth and seventeenth centuries the country was the great gold producer of the world ; now it is said to rank ninth in importance. Iron ore is worked and smelted at Amaga. The authors observe that the gold and silver ores occur either in the acid lavas, which have been erupted at intervals from the close of the Tertiary period to the present time, or in adjacent Archzean schists. In the early days of mining, the superficial weathered rocks, which are the richest, were worked with signal success ; the mines are now sunk below this zone. The ores are found in quartz as fissure- veins in the schists, and also as segregations from the surround- ing lavas. In the latter case, they appear to have come to the surface in the lavas, from which they have to some extent been deached by hot solfataric waters and by tropical rains. Messrs., NEWTON AND Co. inform us that the whole of the Jantern exhibitions at the forthcoming meeting of the British Association at Dover are to be carried out by them. Messrs. PHILIP HARRIS AND Co., Birmingham, have just published a diary which should be of service to science teachers. The diary covers the year from September 1, 1899, to August NO. 155, VOL. 60] INGOT: [SEPTEMBER 7, 1899 31, 1900; and, in addition to the usual blank pages, contains seventy-six pages of tables and definitions frequently required in physical and chemical laboratories. The book is thus similar to an engineer’s pocket-book, and its publication in the form of a diary will make it a constant companion of many science teachers. Messrs. R. FRIEDLANDER AND Son, Berlin, have issued ina single volume the numbers of Watezrae Novztates published by them during 1898. It is well known to collectors of scien- tific books that Messrs. Friedlinder’s publication contains a useful classified list of current literature on all branches of science, compiled from catalogues in many languages. It is convenient to have these bibliographical lists in volume form, and a full index at the end increases their value. — THE additions to the Zoological Society’s Gardens during the past week include a Sykes’s Monkey (Cercopithecus albigu- farts, 8) from South Africa, presented by Mr. W. P. Peyton ; a Common Camel (Camelus dromedarius, 6) from Mogador, presented by Mr. F. G. Aflalo; a Stone Curlew (Oedicnemus scolopax), European, presented by Mr. S. M. Sargant; a Common Raccoon (Procyon lotor) from Barbados, deposited. Errata.—Lord Kelvin asks us to notify the following errata in the MS. of his letter on the ‘f Blue Ray of Sunrise over Mont, Blanc,” published last week (p. 411) :—Line 1, for 5 o'clock read 4 o’clock ; line 7, after ‘‘light’’ insert ‘‘ of sunrise.” OUR ASTRONOMICAL COLUMN. HoutMeEs’ CoMET 1899 @ (1892 III.).— Ephemerts for 12h. Greenwich Mean Time. 1899. - R.A, Decl. Br onlay Se 4 u Sept. 7. 2 6 50°14 tar 41 40'0 8 7 15°57 41 55 35°5 9 7 39°02 42 9 25°93 O'I8I4 005435 10 8 045 42 23 8'0 3 II 8 19°34 42 36 43'8 12 8 37°16 42 50 12°4 13 8 52°40 43 3 33°5 9°1795 005538 14 2 9 5'5r +43) 16 46'9 During the week the comet passes through the north-west of Andromeda, being a few degrees west of y Andromede on the 11th. It is in a good position for observation, but is reported as extremely faint. In Popular Astronomy (vol. vii. pp. 340-342) Prof. C. D. Perrine describes the circumstances of his rediscovery of this comet on June I1 of the present year. The observation was made in the early morning with the 36-inch Lick refractor, the atmospheric conditions being very good. The comet appeared asa round nebulous mass about 30” in diameter, very faint and with but little central condensation, The orbit is more nearly circular than that of any other known comet, lying wholly be- tween the orbits of Mars and Jupiter, thus suggesting a possible, but as yet unproved, connection with the asteroids also occupy- ing that position, THe New ALGOoL VARIABLE IN CyGNus.—The following are the predicted minima of this newly-discovered variable, which will admit of observation during September :— Gbi 35 oo 1899, September ae 12 11 58G.M.T. Zi e5) 27 Mr. J. A. Parkhurst gives (Popular Astronomy, August 1899, vol. vii. p. 380) two charts of the stars in the neighbourhood, which will greatly facilitate the detection of the variable. Observations may be satisfactorily made with telescopes of 3 inches aperture. The position is about 1° south preceding the 5th mag. star o! Cygni. HARVARD COLLEGE OBSERVATORY.—Prof. Pickering has recently issued the second part of vol. xxiv. of Annals of Harvard College Observatory, containing an exhaustive discus- . = be SEPTEMBER 7, 1 8y9} NATURE 4 0 44 sion of the observations made with the meridian photometer during the period 1882-88. The magnitudes, as given in the ‘Harvard Photometry,” are compared with both the ‘* Urano- metria Argentina” and the Boxn Durchmusterung. 4 For the greater part there is close agreement, but the magni- tudes in the Bonn Durchmusterung are found to have a system- atic variation according to the right ascension, the stars grouped at about R.A. 7h., in the Milky Way near Monoceros, being more affected than others also in the Milky Way, but at R.A. 18-19h., in Aquila. Part of the differences between the ‘‘ Harvard Photometry ” values and those of the ‘‘Uranometria Argentina”’ are ascribed to the difference in position of the two stations, as the zenith distances of the stars would be different, and therefore, presum- ably, the atmospheric absorption ; no correction being applied for this, the southern stars at Cordoba would be estimated too bright. Aa attempt to revise the scale of the Durchmusterung de- cided that it was practically impossible to reduce it to the photometric scale by any simple rule, and for purposes of com- parison the necessary corrections are given to convert one scale into the other from magnitudes 1°o to 9°2. Pages 185-233 are devoted to a discussion of the relation be- tween the magnitudes in the Harvard Photometry and those determined by Sir William Herschel. Of the six catalogues of Herschel’s observations, the third is considered more accurate, and the fifth less so, than the others. In all he published ob- servations of 3000 stars, and the average difference from the photometric catalogues of the present day is only +0°16 magni- tude, this including both the possible change duzing the century which has elapsed and the errors of both determinations. Prof. Pickering is sur- prised that these observations should not have been repeated at intervals of ten or twenty years, so that deviations of indi- vidual stars might be detected. With this idea he gives a special table including all stars in which the difference between Herschel’s magnitudes and the photometric ones equals or exceeds half a magnitude. The remainder of the volume, pp. 234- 245, deals with investigations in regard to the relative performance of the large and small meridian photometers which have been employed in the production of the Harvard Photometry itself. No differ- ence exceeding the hundredth of a magnitude was detected. Tables are given showing that the values of the Harvard / hotometry are not sensibly affected by variations of magnitude, right ascension, declination, or proximity to the Milky Way. TORSION-STRUCTURE IN THE ALPS. ONE of the most brilliant and suggestive chapters in Suess’ monumental work ‘‘Das Antlitz der Erde” is that in Ss Fic. 1.—Formation of fold-arcs under the influence of torsion-forces. which he deals with the remarkable whirl shaped arrangement of | the leading lines of the Alpine system (vol. i. chap. 2). Prof. Suess describes how the ‘‘ leading line” sweeps round the northin one great curve convex to the north, the Apennines | describe a curve convex towards the east, whereas the Dalmatian mountains form opposite it a curve convex to the west ; and the curve of the Apennines is continued westward along the Algerian ranges of North Africa, whereas the Dalmatian curve is continued eastward towards Asia Minor. Prof. Suess points out that movements of crust-folding have always. taken place towards the convex or outer side of these curves, and have in most cases caused an actual transgression of the curves above the regions in front of them. He further states that it is not fully understood why the mountain-systems should follow curved lines, or why the curves of the Alpine upheaval should in many areas repeat those of former mountain-systems. _Let me, before going further, remind the reader of a lecture given by one of the greatest of stratigraphers, Prof. Lapworth, at a meeting of the Royal Geographical Society five years ago, and reported in these pages (‘‘ The Face of the Earth,” NATURE, April 26, 1894). This lecture set forth the conception of crust- torsion, demonstrating that ‘‘ like the present surface of a typical geological formation . . . the surface of the earth-crust at the 1 Condensed from the concluding chapter, “Application to the Alps,” in a paper presented at the Roy. Geol. Soc., December 1898. NO. 1558, VOL. 60] present day is most simply regarded as the surface of a con- tinuous sheet which has been warped up by the two sets of undulations crossing each other at right angles. But in the case of the earth-surface, the one set of undulations ranges parallel with the equator, and the other ranges from pole to pole.” Prof. Lossen’s explanation of the involved stratigraphy of the Harz mountains lays the foundation of our knowledge of torsion phenomena in the field, and, although other explanations have been given of the special difficulties in the Harz mountains, Prof. Liéssen’s is now generally accepted. When working out the detailed stratigraphy of a part of the Dolomites, I experienced the same difficulties which Prof, Suess. had indicated in connection with the ‘‘ whirled lines”’ of the Alpine system generally. My results were laid before the Geo- logical Society in December 1898, and are now published in the August issue of the Quart. Journ. Geol. Soc., along witha strati- graphical map of the district examined. In that paper I have tried to show that the possible solution of some of the difficulties lies in the association of torsional movements in conflicting directions through the crust, with movements of crust-folding taking place across a pre-existing set of crust-folds. The change tn the direction of the resultant earth-thrustis the cause to which I have ascribed the torsional phenomena observed in the crust-folds. : The following notes will indicate as briefly as possible where- in the characteristic features of Sella and Enneberg in the Dolomites are analogous with characteristic features of the Alpine system, and how far the elucidation I have offered for that area on the lines of torsion may be capable of a wider application. “ems z, areas of interference ; v, areas of virgation. The stratigraphy of Sella and Enneberg is characterised by twisted strikes, twisted cleavages, twisted arches, twisted troughs, twisted faults, twisted dykes and sills—in fact, the rocks have been twisted and sheared to such a degree that thick deposits have been twined into the form of rock-whorls and large masses of limestone for the greater part changed to dolo- mite. The various combinations of twisted strikes produce the effect of ‘* whirled” stratigraphical lines round individual centres of the region examined. Sigmoid curves in one direction are correlated with sigmoid curves in another, and arcs which are convex towards north and south are connected by virgating lines with arcs which are convex towards east and west. Thus we may say that the curves round the north, east, and south of the Sella mountain resemble the ‘‘ whirl-shaped lead- ing lines” of the Riviera Alps, Apennines and Algerian moun- tains round the western basin of the Mediterranean Sea ; while the curves round the north, west, and south of the Pralongia and Sett Sass area resemble the whirl-shaped lines of the Dal- matian and Pindus mountains and the curvature through the eastern basin of the Mediterranean Sea. The latter curvature resembles that of the mountains around the Roumanian plain, or of the Alps round the plain of Piedmont. Examples might be multiplied interminably, and on great and small scale, ¢he veason being that the essential structure of the Alpine system 7s based upon spirally twisted folds, and not upon linear anticlines and synclines. The formation of fold-arcs is illustrated in the accompanying diagrams (Fig. 1), which show that the action of one torsion- couple must be compensated by the reverse action of a corre- lated torsion-couple, and a fold-arc convex towards one compass direction must be coordinated with a fold-are convex towards the opposite compass direction. When the convexities approach one another during torsional movements the result is that oppositely-curved fold-arcs intertwine in an area which may be 444 WATEUY REE termed an area of ‘‘interference,” to distinguish it from the areas of ‘‘virgation” where fold-arcs curve away from one another. A fold-arc is not a homogeneous fold, but is made up of a series of unit-folds, each of which is the segmental portion of a curve. Any one fold, as it were, dies out in its particular direction and horizon, but is replaced by a fold in the next part of the curve passing through slightly different horizons of the crust. Thus the arc round which a series of unit-folds is ar- ranged comes under the category of curves that change their plane. In Enneberg, series of fold-arcs with their convexities towards different compass directions have been overcast, and the over- cast folds have been penetrated by reverse and normal fault- planes, reverse movement having taken place in the subjacent slices of the overcast folds. But, combined with reverse move- ments in virtue of vertical components, there have been converse movements in virtue of torsional components, so that the actual resultant movement has been spiral—e.g. while the middle or <‘arch”’ slice of an overcast fold moved in clockwise direction and outward, the upper and under slices of the same fold moved in counter-clockwise direction and inward. The problem resolves itself into involute and evolute move- ments of crust-slices with reference to central areas, the evolute slices tending ever to spread, the involute slices ever to narrow. Shear-breccias and fragmentary portions of folds fill up the inwardly-tilted troughs. The fault-rocks in certain of the sheared and twisted troughs of Enneberg had been formerly treated as independent zones of rock, and termed ‘‘ Buchenstein Agglo- merate”’ ; but in my paper they are shown to be practically a **Flysch conglomerate,” formed during the Tertiary epoch of Alpine upheaval. The “‘ Flysch”’ troughs which appear round the Alpine curves may possibly be explained as the result of similar processes of involute and evolute movements going on in slices of closely- piled overcast folds. Thus we might have troughs being twisted inwards and gathering ‘‘ Flysch”’ in variable fragments, while evolute slices of the reciprocal arches were being twisted out- wards, The ‘‘Klippen,” and even the ‘‘ Klippen” ranges, may represent such ‘‘arch’’ wedges of fold-arcs originally closely piled and jammed as the fold-arcs are round the dolomite massives. There is abundant evidence in Enneberg that the molten layers immediately below the crust have shared in the move- ments of torsional-folding. They have filled the body of the virgating fold-arcs produced by these movements, and have there been incorporated in the local crust-whirl of torsion- movements, finding inlet into the planes of fold-shearing, and being dragged and twisted along with adjacent fault-blocks. An inrush during earlier phases of torsion has been in its turn in- vaded by the next inrush, and so on, in accordance with the gradual progress of torsion ; the latest invasions occur along transverse and oblique faults, belonging to a system of faults which has affected Oligocene strata in the Judicarian area; hence such injected rock is not older than Middle Tertiary. The fundamental feature of torsional folding may be said to be centralisation ; whether it be involution of certain horizons in covered troughs, or evolution of other horizons in overcast arches, the movements have reference to the centres of torsion- basins and torsion: buckles. The principles thus demonstrated in Enneberg will be seen to involve the ‘‘ fan-shaped structure” of central massives. They could not fail to do so, since they have been deduced from the stratigraphy of Sella massive in Enneberg, which presents a wonderfully symmetrical, although obliquely elongated example of ‘* fan-structure.” I have shown in my paper on Enneberg that the transverse faults define a later or Tertiary series of arches and troughs, through whose septal portions they chiefly pass. The faults are shearing-planes, and are the result of oppositely-directed move- ments of twisting and thrusting which have taken place from Opposite arches upon common reciprocals, the intermediate troughs. These movements have produced the virgating groups of north and south fold-arcs which meet the east and west fold- arcs, and the sigmoidal combinations of torsional fold-arcs and fault-curves represented in Fig. 2. The continuance of the faulting during a protracted period of crust-adjustment has caused displacement of the arcs on the opposite sides. NO. 1558, VOL. 60] [SEPTEMBER 7, 1899 There are several well-known lines of tranverse and oblique shearing through the Alps which repeat these phenomena on a larger scale, and at the same time no detail is wanting in the comparison. Some of these may be indicated :.(1) The Judicarian-fault ; (2) Iseo-Ortler; (3) Como-Sonthofen ; (4) Maggiore-Sargans ; (5) Tarentaise-Thun ; (6) Savoy-Freyburg— all these represent directions of inthrow and faulting along the *“septum”’ or ‘‘ middle limb” between great transverse arches and troughs which form part of major Alpine torsion-curves. With regard to the eastern Alps, there are also well-marked N.N.E.-S.S.W. directions of faulting and displacement. The pre-eminent example is the remarkable series of down-throws at the eastern limit of the Alps, with which is associated the dis- placement of the northern curve of the Alps towards the Carpathian curve. At the same time, the influence of the co- ordinated torsional movements round the Hungarian basin is evidenced in the eastern Alps by N.N.W.-S.S.E. directions of transverse-shearing. All the transverse directions of tectonic disturbance in the Alps have in common with the parallel Enneberg lines (a) the Fic. 2.—Superposition of a later series of arches and troughs upon an east and west series (a, s); chief result, overcasting and overthrusting of old and new arches over synclinal troughs. = ---= fold-curves and faults formed by the twisted shearing. virgation from them of an eastern and western series of torsion- curves, representing fold-arcs; (4) the injection of igneous rock along the main direction of ‘‘septal” shearing, associated with the presence of larger masses in the areas of fold-expansion ; (c) the fact that they have continued to act as lines of crust- adjustment subsequently to the period of acute torsional up- heaval. In the Alps the repeated displacement of the main chain to the north would simply indicate that the arch on the east of any transverse depression had been originally less elevated than the arch on the west of the same depression. The extent to which eastern curves have been twisted away from western curves originally belonging to the same ‘‘ bundle” of virgating folds, may give us some idea of the tremendous shear- ing that has taken place, and the great compression that the Alpine regions have sustained from east and west in virtue of this oblique, sigmoidal movement of opposite arches over intervening synclines (Fig. 3). The law which I deduced from my observations at Sella was that the southwardly-convex torsion curves are marked by over- <= ee ee ee SEPTEMBER 7, 1899 | WaALURE 445 thrust of the folds towards the south, the northwardly-convex curves by overthrust of the folds towards the north. This law agrees with the movements which Prof. Suess has described along the curved lines of Alpine upheaval, and finds further confirmation in the curious effects of reversal of thrust-move- ments which are so highly characteristic of all the great transverse Alpine arches. To cite one example, compare the great overthrusts round the south curves of the western Alps with the northwardly-directed overthrusts in the Bernese Oberland. The drawing (Fig. 3) shows that the eastern and western fold- ares associated with any transverse direction of faulting provide the same fundamental conditions of peripheral overthrusts with reference to definite centres which I demonstrated in Enneberg. And as the centres are comprised in the very highest transverse Alpine arches which were determined during the later epoch of | Alpine upheaval, it is here that, according to torsional laws, the | highest individual massives should be present. The essential structure is the same, whether it be exempli- | fied in the variously-shaped dolomite massives or in the variously-shaped central massives—elliptical, lenticular, or elongated, clearly or less clearly defined from one another— all may be regarded as an inevitable result of crust-torsion. Even when considerable subsequent faulting and lateral displacement might seem to have obliterated the original relation- ship of opposite torsion-curves, there are long streaks or inter- rupted appearances of igneous injections along the main fault- line, which afford evidence of a probable original connection between eastern and western fold-arcs now fairly remote from one another. The more or less sickle-shaped form of some Alpine curves represents a north and south fold-are on the same side of a transverse direction of shearing. The Enneberg curve (Langs-da-Fiir, Campo- lungo, Cherz Hill) is an example on a small scale, the Banat curve round the Roumanian Plain isan example on a grand Scale. The chief line of fault there is the «* Banat” line, which in its tectonic rela- tions bears a strong resemblance to the Judicarian line. It runs north and south and separates a western area of mica schists from an eastern depressed area of Jurassic and Cretaceous strata, eruptive rocks occurring at intervals along the fault. In describing the Banat fault, Prof. Suess never doubts the Tertiary age of the folds and of the eruptive rocks associated both with the folds and with the fault. Ie notes the twisting character of the strike, and ex- pressly states that the eruptive rocks ““must have been Tertiary notwith- standing the resemblance almost amounting to identity which they present with those of the Judicarian and Predazz0 areas (‘‘Antlitz,” i. p. 623 and pp. 210-213; the italics are mine). Further, he quotes Dr. Posepny’s opinion “ that these eruptive masses are not masses exerting pressure, but themselves pressed. The subsidence of a neighbouring dis- trict induces such eruptions, but the eruptive masses themselves are pressed into the dykes by the pressure of the sinking masses” (2. ¢. p. 210). Similar reasoning was followed by Dr. Salomon in his paper on the Peri-Adriatic eruptive masses, wherein he advocated the theory that the Peri-Adriatic masses originated in consequence of the Peri-Adriatic subsidence, and were of the age of the subsidence. I would be inclined to class both the Judicirian and Banat faults as phenomena of torsional eruptivity which may, upon the evidence of the sedimentary strata involved in the folds, be referred to the Mid-Tertiary epoch of Alpine upheaval. Two great internal torsion-basins within the Alpine systems of southern Europe are the Hungarian and the west Mediter- ranean. The arrangement of the Carpathian mountains round the Hungarian basin presents all the characteristic features of torsion. Mountain fold-arcs have formed peripherally, and broken arches have been thrust outwards and upwards from the basin, while fold-slices produced by normal faulting have had an involute movement inward and downward. Eruptivity has been particularly active in the main septal zone between NO. 1558, VOL. 60] the oppositely moving portions of the fold-arcs. The Dalmatian mountains represent a series of peripheral folds whose arches have moved towards the south-west, while the eastern Alps betray the influence of this movement of folding, and also a co- ordinated movement to north-west. The centrifugal movements round the periphery of the western part of the Mediterranean basin have caused the up- | folding of the Apennines towards the north-east, and again an igneous zone runs irregularly between the area of peripheral out-thrust and inward down-throw. _ It is still further within the igneous zone that we must look for the buckling-up of new rock-folds, but the new folds can never be absolutely parallel with the predecessors, sévce crwst-torsion zs going on all the time. Hence the virgation of successively formed ranges in great mountain systems would appear to rest upon much the same principle as the virgation of fold-arcs illustrated at Groden Pass in Enneberg (Q.7.G.S., August 1899, /.c., Plate I.). While torsion-basins tend by reason of repeated buckling to narrow within themselves, the tendency of the regions outside the outermost peripheral fold-arcs is to subside towards the torsional sag. To such return involute movements we may probably attribute the present subsidence going on in the Adriatic areas, as also the tendency for lakes and plains to form on the outer skirts of torsional mountain-systems. The Caucasus mountains afford an example of the occurrence of an internal area of down-throw in various parts of which Fic. 3.—The leading oblique arches and troughs of the Tertiary upheaval of the Alps. (The trouzhs are shaded, the arches are between the troughs, and the chief fold-arcs of the mountain masses are indicated within the arches by shading and broken lines.) vulcanicity has been active, and of outer areas along which overcast folds of immense size have been gradually involuted. The Alps show at the present day an advanced phase in their torsional history. Earlier outer folds have been broken down owing to dynamic as well as aérial causes of denudation, and have disappeared along interrupted outer shear-zones which I would identify as those occupied by ‘‘ Flysch” rocks of what- ever age. These rocks represent the necessary deformation of older and less twisted folds by the process of involution during the gradual evolution of later and more twisted folds. Such an explanation of the relation of the Flysch to the present Alps would agree with the observed fact that fragments of gran- itoid and metamorphic rocks contained in the Flysch show less metamorphic change than those in the central massives of the Alps, since it would relate the Flysch to lost earlier folds which had undergone a smaller degree of torsion than the succeeding folds. The widely-extended subsidence during Jurassic and the greater part of Cretaceous time in Europe seems to have been the turning- point in the history of Alpine upheaval, since previously, in Alpine regions, the resultant forces had acted more strongly from north and south than from east and west, and afterwards the move- ments came almost transversely. Hence the long continuation of the great Mesozoic epoch of deposition and subsidence, in inducing the strong action of east and west crust-strains over a region where previously the action of north and south crust- 446 NATURE [SEPTEMBER 7, 1899 strains had been pre-eminent, has probably been the initiative cause of an acute epoch of crust torsion and folding along oblique and transverse lines. The new movements affected all European areas, dovetailing new folds into the midst of, and across, old folds, and determin- ing new centres of virgation. In the Alps new arches and troughs were formed obliquely and transversely across the older series; the first-formed basins in the themselves over-arched or blocked up as the fan-shaped mountain- massives gradually became more and more compactly pressed middle than near either bank. If we could look beneath the surface and see what was going on there, we should find that the velocity was not so great near the bottom as at the top, and was scarcely the same at any two points of the depth. The more we study the matter, the more complex the motion appears to be; small floating bodies are not only carried down at dif- | ferent speeds and across each other’s paths, but are whirled new movement were | together, and the great torsion-basins of southern Europe | became ccnfirmed in their new shape and position acquired in accordance with the altered conditions of crust equilibrium. As might be expected, there is frequent indication that eruptive activily in Tertiary time broke out afresh in the same areas where eruptive activity had marked the Upper Carboniferous and Permo-Triassic period of movements. But the chief groups of eruptive rock round the inner caves of the Alps, Apennines and Carpathians, as well as the injections along oblique directions of shearing, may be clearly identified with the Tertiary torsion movements, for the most part, with the acute Mid-Tertiary epoch of torsion. Fic. 2. central massives may belong in part to the ancient Paleozoic or Permo-Carboniferous epochs of upheaval, in part to the late- Mesozoic and Tertiary epochs. A general conclusion may be made from the above that there are serpentines, diorites, granites, felsites, basalts in Alpine folds and faults which can be identified more especially with the ‘‘evolute” phenomena of Tertiary torsional movements. And these intrusions, injections, and eruptions involved in the last acute epoch of upheaval in Southern Europe are clearly correlated with similar eruptive phenomena throughout the same period in other parts of Europe, e.g. Auvergne, Scotland, Iceland. MariA M. OGILVIE. THE MOTION OF A PERFECT LIQUID} [F we look across the surface of a river, we cannot fail to observe the difference of the movement at various points. Near one bank the velocity may be much less than near the ‘ther, and generally, though not always, it is greater in the urse delivered at the Royal Institution on Friday, February 10, by Prof. H. S. Hele-Shaw. NO. 1558, VOL. 60] round and round in small whirlpools, sometimes even disappear- ing for a time beneath the surface. By watching floating bodies we can sometimes realise these complex movements, but they may take place without giving the slightest evidence of their existence. You are now looking at water flowing through a channel of varying cross section, but there is very little evidence of any dis- turbance taking place. By admitting colour, although its effect is at ence visible on the water, it does not help us much to understand the character of the flow. If, however, fine bubbles of air areadmitted, we at once perceive (Fig. 1) the tumultuous conditions under which the water is moving and that there is a strong whirlpool action. This may be intensified by closing in two sides (Fig. 2), so as to imitate the action of a sluice gate, The larger masses of ignecus rocks in the | through the narrow opening of which the water has all to pass, the presence of air making the disturbed behaviour of the water very evident. Now you will readily admit that it is hopeless to begin to study the flow of the water under such conditions, and we naturally ask, are there not cases in which the action is more simple? Such would be the case if the water flowed very slowly in a perfectly smooth and parallel river bed, when the particles would follow one another in lines called ‘‘stream- lines,” and the flow would be like the march of a disciplined army, instead of like the movement of a disorderly crowd, in which free fights taking place at various points may be supposed to resemble the local disturbances of whirlpools or vortices. The model (Fig. 3) represents on a large scale a section of the channel already shown, in which groups of particles of the water are indicated by round balls, lines in the direction of flow of these groups (which for convenience we may call particles) being coloured alternately. When I move these so that the lines are maintained, we imitate ‘‘stream-line” motion, and when, at any given point of the pipe, the succeeding particles always move at exactly the same velocity, we have what is understood as ‘‘ steady motion.” SEPTEMBER 7, 1899] IEAM Fee ~ 447 As long as all the particles move in the straight portion of the channel, their behaviour is easy enough to understand. But as the channel widens out, it is clear that this model does not give us the proper distribution. In the model the wider por- tions are not filled up, as they would be with the natural fluid ; for it must be clearly understood that the stream-lines do not flow on as the balls along these wires, passing through a mass of dead water, but redistribute themselves so that every particle of water takes part in the flow. Perhaps you may think that if these wires were removed, and the wooden balls allowed to find their own positions, they would group themselves as with an actual liquid. This is not the case; and, for reasons that you will see presently, no model of this kind would give us the real conditions of actual flow. By means of a model, however, we may be able to understand why it is so absolutely essential we should realise the correct nature of the grouping which occurs. First look at the two diagrams (Figs. 4 and 5), which you will see represent channels of similar form to the experimental one. The same number of particles enter and leave in each under apparently the same conditions, so that the idea may naturally arise in your minds, that if the particles ultimately flow with the same speed whatever their grouping in the larger portion of the channel, it cannot much matter in what particular kind of formation they actually pass through that wider portion. To understand that is really very important. ees SSeses Cc og Stee en ae) es You will see that we have two lines of particles which we may consider stream-lines, those on the left coloured white, and those on the right coloured red. The first and last are now exactly 18 inches apart, there being eighteen balls of 1 inch diameter in the row. If I move the red ones upward, I cause them to enter a wider portion of the channel, where they will have to arrange them- model (Fig. 6) specially made for the purpose. selves so as to be three abreast (Fig. 7). It is quite clear to you, that as I do this their speed in the wider portion of the channel is only one-third of that in the narrow portion, as you will see from the relative positions of the marked particles. Now, directly the first particle entered the wider channel, it commenced to move at a reduced speed, with the result that the particles immediately behind it must have run up against it, exactly in the same way that you have often heard the trucks in a goods train run in succession upon the ones in front, when the speed of the engine is reduced; and you will doubtless have noticed that it was not necessary for the engine actually to stop in order that this might take place. Moreover, the force of the impact depended largely upon the suddenness with which the speed of those in front was reduced. Applying this illustration to the model, you will see that the impact of these particles in the wider portion would necessarily involve a greater pressure in that part. Turning next to the white balls, I imitate, by means of the left-hand portion, the flow which will occur in a channel six times as large as the original one, and you now see (Fig. 7) that as the particles have placed them- selves six abreast, and the first and last row are 3 inches apart NO. 1558, VOL. 60] instead of 18 inches, the speed in the wider portion of the channel must have been one-sixth of that in the narrow portion, Evidently, therefore, the velocity of the particles has been reduced more rapidly than in the previous case, and the pressure must consequently be correspondingly greater. We may now take it as perfectly clear and evident, that the pressure is greater in the wider portion and less in the narrower portion of the channel. Turning now to the two diagrams, we see that the pressure is in each case greater in every row of particles as in the wider portions of the channel, but that instead of being suddenly increased, as in the model, it is gradually increased. The width of the coloured bands, that is, rows of particles, or width apart of stream-lines, is a measure of the increased pressure. Thus you will now regard the width of the bands, or what is the same thing, the distance apart of the stream-lines, as a direct indication of pressure, and the narrowness or closeness of the stream-lines as a direct indication of velocity. Next notice the great difference between the two diagrams. In one diagram (Fig. 4) the change of width is uniform across the entire section. In diagram (Fig. 5), however, this is not the case. In the narrowest portion of the channel in each dia- gram there are seven colour bands of little balls each contain- ing three abreast, but we find that in one diagram (Fig. 4) they Ss Let us consider a | the other diagram (Fig. 5) are equally spaced in the wider part six abreast throughout. In the outer row is spaced eight abreast, | the second row rather more than six, and the inner rows rather GOSIOPGVQVOVOGE DOO Fic. 6. Fic. 7 more than four abreast, and the middle row less than four abreast, making in all forty-two in a row, as in the previous case. One diagram (Fig. 5) therefore will represent an entirely different condition to the state represented by the other diagram (Fig. 4), the pressure in the wide part of the latter varying from 4 maximum at the outside to a minimum in the middle, while the corresponding velocity is greatest in the middle and least at the outside or borders. Now, when we know the pressure at every point of a liquid, and also the direction in which the particles are moving, together with their velocity at every point, we really know all about its motion, and you will see how important the question of grouping is, and that, in fact, it really constitutes the whole point of my lecture to-night. How then shall we ascertain which of the two groupings (Fig. 4 or 5) is correct, or whether possibly some grouping totally different from either does not represent the real conditions cf flow ? Now, the model does not help us very far, because there seems to be no means of making the grouping follow any regular law which might agree with fluid motion. In whatever way we improve such a model, we can scarcely hope to imitate by merely mechanical means the motion of an actual liquid, for reasons which I will now try to explain. In the first place, apart from the particles having no dis- tinguishing characteristics, either when the liquid is opaque or transparent, they are so small and their number is so great as to be almost beyond our powers of comprehension, Let me try, by means of a simple illustration, to give some idea of their number, as arrived at by perfectly well recognised methods of physical computation. Lord Kelvin has used the illustration that, supposing a drop of water were magnified to the size of the 448 NATUKE [SEPTEMBER 7, 1899 earth, the ultimate particles would appear to us between the size of cricket-balls and foot-balls. I venture to put the same fact in another way, that may perhaps strike you more forcibly. This tumbler contains half a pint of water. I now close the top. Suppose that, by means ofa fine hole, I allow one and a half billion particles to fow out per second—that is to say, an exodus equal to about one thousand times the population of the world in each second,—the time required to empty the glass would be between (for of course we can only give certain limits) seven million and forty-seven million years. In the next place, we have the particles interfering with each other’s movements by what we call ‘‘ viscosity.” Of course, the general idea of what is meant by a ‘‘ viscous” fluid is familiar to everybody, as that quality which treacle and tar possess in a markéd degree, glycerine toa less extent, water to a less extent than glycerine, and alcohol and spirits least of all. In liquids, the property of viscosity resembles a certain positive ‘* stickiness ” of the particles to themselves and to other bodies ; and would be well represented in our model by coating over the various balls with some viscous material, or by the clinging together, which might take place by the individuals of a crowd, as contrasted with the absence of this in the case of no viscosity as represented by the evolutions of a body of soldiers. It may be accounted for, to a certain extent, by supposing the particles to possess an irregular shape, or to constantly move across each other’s paths, causing groups of particles to be whirled round together. Whatever the real nature of viscosity is, it results in producing in water the eddying motion which would be perfectly impos- sible if viscosity were absent, and which makes the problem of the motion of an imperfect liquid so difficult and perplexing. Now, all scientific advance in discovering the laws of nature has been made by first simplifying the problem and reducing it to certain ideal conditions, and this is what mathematicians have done in studying the motion of a liquid. We have already seen what almost countless millions of particles must exist in a very small space, and it does require a much greater stretch of the imagination to consider their number altogether without limit. If we then assume that a liquid has no viscosity, and that it is incompressible, and that the number of particles is infinite, we arrive at a state of things which would be represented in the case of the model or the diagram on the wall, when the little globes were perfectly smooth, perfectly round and perfectly hard, all of them in contact with each other, and with an unlimited number occupying the smallest part of one of the coloured or clear bands. This agrees with the mathematical conception of a perfect liquid, although the mathematician has in his mind the idea of something of the nature of a jelly consisting of such small particles, rather than of the separate particles themselves. The solution of the problem of the grouping of the little particles, upon which so much de- pends, and which may have at first seemed so simple a matter, really represents, though as yet applied to only a few simple cases, one of the most remarkable instances of the power of higher mathematics, and one of the greatest achievements of mathematical genius. You will be as glad as I am that it is not my business to-night to explain the mathematical processes by which the behaviour of a perfect liquid has been to a certain extent investigated. You will also understand why such models as we could actually make, or any analogy with the things with which we are familiar, would not help us very much in obtaining a mental picture of the behaviour of a perfect liquid. If, for instance, we try to make use of the idea of drilled soldiers, and move the lines with that object in view, we see that instead of the or- dinary methods of drill, the middle rank soon gains on the others, and enters again the parallel portion of the channel in a very different relative position to the opposite lines, although the stream-lines would all have the same actual velocity when once again in the parallel portion. Since, then, we cannot use models or any simple analogy with familiar things, or follow— at any rate this evening—the mathematical methods of dealing with the problem, what way of understanding the subject is left to us? If we take two sheets of glass, and bring them nearly close together, leaving only a space the thickness of a thin card or piece of paper, and then by suitable means cause liquid to flow under pressure between them, the very property of viscosity, which, as before noted, is the cause of the eddying motion in large bodies of water, in the present case greatly limits the NO. 1558, VOL. 60] freedom of motion of the fluid between the two sheets of glass, and thus prevents, not only eddying or whirling motion, but also counteracts the effect of inertia. Every particle is then com- pelled by the pressure behind and around it to move onwards without whirling motion, following the path which corresponds exactly with the stream-lines in a perfect liquid. If we now, by a suitable means, allow distinguishing bands of coloured liquid to take part in the general flow, we are able to imitate exactly the conditions we are seeking to understand. (Prof. Ilele-Shaw here gave demonstrations of the stream-lines in liquids flowing under the conditions of a gradually enlarging and contracting channel. He proved that the condition of flow corresponded closely with that shown in Fig. 5 and xof with that given in Fig. 4. The method of the experiments has already been described in NaTuRE (vol. lviii. p. 34), though by using glycerine instead of water much more perfect results were obtained than in those then described. ] But at this stage you may reasonably inquire how it is that we are able to state, with so much certainty, that the artificial conditions of flow with a viscous liquid are really giving us the stream-line motion of a perfect one ; and this brings me to the results which mathematicians have obtained. The view now shown represents a body of circular cross- section, past which a fluid of infinite extent is moving, and the lines are plotted from mathematical investigation and represents the flow of particles. This particular case gives us the means Ric. 8. of most elaborate comparison ; although we cannot employ a fluid of infinite extent, we can prepare the border of the channe} to correspond with any one of the particular stream-lines, and measure the exact positions of the lines inside. By means of a second lantern, the real flow of a viscous liquid for this cdse is shown upon the second screen, and you will see that it agrees with the calculated flow round a similar obstacle of a perfect liquid. The diagram shown on the wall is the actual figure employed for comparison, and upon which the experimental case was projected. By this means, it was proved that the two were in absolute agreement. If we start the im- pulses, as before, in a row, we at once see how the middle particles lag behind the outer ones, as indicated by the width of the bands, showing that it is not necessarily the side stream- lines that move more slowly. It may be more interesting to you to see, in addition to the foregoing case—in which for conveni- ence, and as quite sufficient for measurement only, a semi-cylinder was employed—the case of a complete cylinder (Fig. 8). In this case two different colours are used in alternate bands, and these bands are sent in, not steadily, but impulsively, in order to illustrate what I have just pointed out. You will see how the greater width of the colour bands before and behind the cylinder indicates an increase of pressure in those regions. This in a ship-shape form accounts for the standing bow and stern — SEPTEMBER 7, 1899] waves, whereas the narrowing of the bands at the sides indicates an increase of velocity and reduction of pressure, and accounts for the depression of water level, with which you are doubtless familiar, at the corresponding part of a ship. I will now take amore striking case. If, instead of a circular body, we had a flat plate, the turbulent nature of the flow is evidently very great, as you will see from the view (Fig. 9), which is a photograph of the actual flow under these conditions, made visible by very fine air bubbles, and showing water at rest in the clear space behind the obstacle. We can, however, take steps to reduce this turbulence, and you now see on the second screen the flow by means of appar- atus which time does not permit me to describe, but which gives a slow and steady motion that it would be impossible to improve upon in actual conditions of practice, or even, I am inclined to think, by any experimental method. Instead of using air to make this flow clear, we now allow colour to stream behind the plate, and you will see that the water still refuses to flow round to the back, and spreads on either side. We have so slow a velocity as not to induce vortex motion, but the inertia of the particles which strike the flat plate causes them to be deflected to either side, exactly as tennis-balls in striking against a wall obliquely. The sheet of water is so thick, that is to say, the parallel glass plates are so far apart, that they do not enable the viscosity of the water to act as a sufficient drag to prevent this taking place. Mathematicians, however, predicted with absolute certainty that with stream-line motion, the water should flow round and meet at the back, a state of things that, however slow we make the motion in the present case, does not occur owing to the effect of inertia. They have drawn with equal confidence the lines along which this should take place. Wecould either effect NO. 1558, VOL. 60| NATURE | the line may take. 449 this result with the experiment you have just seen, by using a much more viscous liquid, such as treacle, or, what comes to the same thing, bringing the two sheets of glass nearly close to- gether ; and the flow which you are now witnessing (Fig. 10) shows the result of doing this. The colour bands in front of the plate no longer mix at all with the general body of flow, or are unsteady, as was the case in the last experiment, but flow round the plate, and flow so steadily, that unless we jerk the flow of the colour bands, it is impossible to tell in which direction they are actually mcving. It is interesting to note that where the divided central colour band re-unites is clearly shown in the illustration, Whilst I have been dealing with the stream-lines ofa perfect liquid, your minds will doubtless have turned to the lines along which magnetic and electrical forces appear to act. We are possibly further from realising the actual nature of these forces, than from a correct conception of the real nature of a liquid. Wehave long agreed to abandon the old ideas of the electrical and magnetic fluids flowing along these lines, and to substitute instead the idea that these lines represent merely the directions in which the forces act. Now we can easily see that this conception is quite a reasonable one, for in the case of the model it is not necessary to have the row of balls actually moving in order that the effect may be transmitted along the different linesthey occupy. If I attempt to raise the plate upon which they rest, the pressure is instantly transmitted through the whole row to the top ball along each line, whatever curve In the same way, you will remember that it was not necessary to have the colour bands actually in motion, for, though apparently free to move in any direction, they retain | their form for a considerable time, and the path along which they would influence each other as soon as the tap is opened would be along those lines in which the liquid was flowing before it was brought to rest. Hence it is possible, with some suitable means, to cause a viscous liquid to reproduce exactly the lines of magnetic and electrical induction. In the case of magnetism and electricity, it is of course possible, by means of a small mag- netic needle or a galvanometer, by exploring the whole surface through which magnetic induction or elec ical flow is acting, to plot the lines of force for innumerable cases, where we can work in air or on the surface of the solid conductor. But in this building it seems natural to take as an example the case first used by the great man to whom the conception of lines of magnetic force is due, for the first reference I have been able to find to such lines is in one of Faraday’s earliest papers on the indication of electric currents (‘‘ Experimental Researches in Electricity,” vol. i. p. 32), in which he says, ‘‘ By magnetic curves I mean the lines of magnetic forces, however modified by the juxtaposition of poles, which would be depicted by iron 450 NATURE [SEPTEMBER 7, 1899 filings, or those to which a very small magnetic needle would form a tangent.” You are all familiar with the way in which iron filings set themselves when shaken over the north and south poles of a magnet. The magnetic lines are then nearly, but not quite, circular curves between the two poles. Now, the mathematics of the subject tells us that if the poles could be regarded as points, the lines of force between them would be perfect circles. You are now looking at the colour bands, the edges—or indeed any portion—of which represent lines obtained by admitting coloured liquid from a series of small holes round a central small orifice, which admits clear liquid, and allows them to escape through another small orifice (called respectively in hydromechanics a source and szz/), and I leave it to you to judge how far these curves deviate from the ideal form. My assistant is now allowing the colour to flow, first steadily, and then in a series of impulses, and the latter gives us the con- ception of waves or impulses of magnetic force, though of course the magnetic transmission force would be instantaneous. Regarded as a liquid, it is here again clear how absolutely the truth of our views concerning the slower movement in the wider portion is verified by this experiment. A last experiment shows the streams admitted, not from a source, but from a row of orifices in what corresponds to the slowest moving portion of the flow. The result is that the colour bands are much narrower, and although the circular forms of the curves are, as in the previous experiment, pre- served, the lines are so fine at the point of exit, which, as before, corresponds to the South Pole, as to really approximate to ideal stream-lines. The same method enables us to trace the lines of force through solid conductors, for, as long as we confine ourselves to two dimensions of space we may have flat conductors of any shape whatever. But it does something more, for by making the film rather deeper in some places than others, more particles arrange themselves there, and the lines of flow will naturally tend in the direction of the deeper portion. This will give the stream-lines identically the same shape as the magnetic or elec- trical curves which encounter in their paths a body of less resistance, for instance, a para-magnetic body. If, on the other hand, at these points the film is made rather thinner, less particles will be able to dispose of themselves in the shallow portion of the film, and hence the lines of flow will be pushed away from this portion, giving us exactly the same forms as magnetic lines of force in a magnetic field in proximity to a diamagnetic body. Here, again, mathematical methods have enabled lines of actual flow to be predicted, and you may compare the actual flow for the case of a cylindrical para-magnetic body, which was worked out some years ago. You will doubtless not be inclined to question the practical value of stream-lines in the subject which we have just been considering, because, unlike the flow of an actual liquid, magnetic lines of force can never be themselves seen, and because there is no doubt as to the correspondence of the directions to the lines of a perfect liquid. It was the conception of these lines in the mind of Faraday, and more particularly their being cut by a moving wire, that euabled him to realise the nature of the subject more clearly than any other man at the time, and to do much towards the rapid development of electrical science and its practical applications. When we come to consider the relation of the study of the motion of a perfect liquid with hydromechanics and naval architecture, it must be admitted that the matter is a difficult one. Probably one of the most perplexing things in engineer- ing science is the absence of all apparent connection between higher treatises on hydrodynamics and the vast array of works on practical hydraulics. The natural connection between the treatises of mathematicians and experimental researches of engineers would appear to be obvious, but very little, if any, such connection exists in reality, and while at every step elec- trical applications owe much to the theories which are common to electricity and hydromechanics, we look in vain for such applications in connection with the actual flow of water. Now the reason for this appears to be the immense difference between the flow of an actual liquid and that of a perfect one owing to the property of viscosity. A comparison of the perous experinignis which you have seen to some extent in- dicates this. NO. 1558, VOL. 60] In the first place, let us consider for a moment some of the things which would happen if water were a perfect liquid. In such a case, a ship would experience a very different amount of resistance, because, although waves would be raised, owing to the reasons which we have already seen, the chief causes of resistance, viz. skin friction and eddying motion, would be entirely absent, and of course a submarine boat at a certain depth would experience no resistance at all, since the pressures fore and aft would be equal. On the other hand, there would be no waves raised by the action of the wind, and there would be no tidal flow, but to make up for this rivers would flow with incredible velocity, since there would be no retarding forces owing to the frictionof the banks. But the rivers themselves would soon cease to flow because there would be no rainfall such as exists at present, since it is due to viscosity that the rain is distributed, instead of falling upon the earth in a solid mass when condensed. In a word, it may be said that the absence of viscosity in water would result in changes which it is impossible to realise. We may now briefly try to consider the difference between practical hydraulics and the mathematical treatment of a perfect liquid. the flow of water appears to have been made by a Roman engineer about 1800 years ago, an effort being made to find the law for the flow of water from an orifice. For more than 1500 years, however, even the simple principle of flow according to which the velocity of efflux varies as the square of the head, or what is the same thing, the height of surface above the orifice varies as the square of the velocity, remained unknown. Torricelli, who discovered this, did so as the result of observing that a jet of water rose nearly to the height of the surface of the body of water from which it issued, and concluded therefore that it obeyed the then recently discovered law of all falling bodies. Though it was obvious that this law did not exactly hold, it was a long time before it was realised that it was the friction or viscosity of liquids that caused so marked a deviation from the simple theory. Since then problems in practical hydraulics, whether in connection with the flow in rivers or pipes, or the resistance of ships, have largely consisted in the determination of the amount of deviation from the foregoing simple law. About one hundred years ago it was discovered that the re- sistance of friction varies nearly in accordance with the simple law of Torricelli, and also—although for a totally different reason—the resistances due to a sudden contraction or enlarge- ment of cross-section of channel or to any sudden obstructions appear to follow nearly the same law. Now it is extremely convenient for reasons which will be understood by students of hydraulics to treat all kinds of resistance as following the same law, viz. square of velocity which the variation of head or height of surface has shown to do. But this is far from being exact, and an enormous amount of labour has conse- quently been expended in finding for all conceivable conditions in actual work tables of coefficients or empirical expressions which are required for calculations of various practical ques- tions. Such data are continually being accumulated in con- nection with the flow of water in rivers and pipes for hydraulic motors and naval architecture. This is the practical side of the question. On the other hand, eminent mathematicians, since the days of Newton and the discovery of the method of the calculus, have been pursuing the investigation of the behaviour of a perfect liquid. The mathematical methods, which I have already alluded to as being so wonderful, have, however, scarcely been brought to bear with any apparent result upon the behaviour of a viscous fluid. Indeed, the mathematician has not been really able to adopt the method ot the practical investigator, and deal with useful forms of bodies such as those of actual ships, or of liquid moving through ordinary channels of varying section, even for the case of a perfect liquid, but he has had to take those cases, and they are very few indeed, that he has been able to discover which fit in with his mathematical powers of treatment. This brief summary may possibly serve to indicate the nature of the difficulties which I have pointed out, and will show you the vast field there yet lies open for research in connection with the subject of hydromechanics, and the great reception which awaits the discovery of a theoretical method of completely deal- ing with viscous liquids, instead of having recourse as at present principally to empirical formula based on the simple law already alluded to, The earliest attempts to investigate in a scientific way | SEPTEMBER 7, 1899 | NATURE 451 We may, however, console ourselves with the thought, that in the application of the laws of motion themselves to azy terrestrial matters, the friction of bodies must always be taken into account, and renders it necessary, that we should commence by studying the ideal conditions. In this as in other matters, the naval architect and engineer must always endeavour as far as possible to base their considerations and work upon the secure foundation of scientific knowledge, making allowances for disturbing causes, which then cease to be the source of per- plexity and confusion. From this point of view, the study of the behaviour of a perfect liquid, even when no such form of matter appears to exist, has an interest for the practical man in spite of the deviation of actual liquids from such ideal con- ditions. If the truth must be told, it is such a deviation from the simple and ideal conditions that really constitute the work of a professional man, and it is only practical experience which, based upon sound technical knowledge, enables 50,000 tons of steel to be made to span the Firth of Forth, Niagara to be harnessed to do the work of 100,000 horses, or an Oceanic to be slid into the sea with as little misgiving as the launch of a fishing-boat. Ihave, Iam afraid, brought you only to the threshold of a vast subject, and in doing so have possibly employed reasoning of too elementary a kind. After all, I may plead that I have followed the dictum of Faraday, who said, ‘* If assumptions must be made, it is better to assume as. little as possible.” If I have assumed too little knowledge on your part, it is because of the difficulties I have found in the subject myself. If I have left more obscure than I have been able to make clear, it is consoling to think how many centuries were required to dis- cover even what is known at the present time, and we may well be forgiven if we cannot grasp at once results which re- present the life-work of some of the greatest men. A PROBLEM IN AMERICAN ANTHRO- POLOG Y. V HILE engaged in writing the address that I am to read to you this evening, the sad news reached me of the death, on July 31, of our President of five years ago, Dr. D. G. Brinton. Although not unexpected, as his health had been failing since he was with us at the Boston meeting, where he took his always active part in the proceedings of Section H, and gave his wise advice in our general council, yet his death affects me deeply. I was writing on a subject we had often discussed in an earnest but friendly manner. He believed in an all-pervading psycho- logical influence upon man’s development, and claimed that American art and culture were autochthonous, and that all resemblances to other parts of the world were the results of corresponding stages in the development of man; while I claimed that there were too many root coincidences with variant branches to be fully accounted for without also admitting the contact of peoples. Feeling his influence while writing, I had hoped that he would be present to-night, for I am certain that no one would have more readily joined with me in urging a suspension of judgment, while giving free expression to opinions, until the facts have been worked over anew, and more knowledge attained. Now that his eloquent tongue is silent and his gifted pen is still, I urge upon all who hear me to-night to read his two addresses before this Association—one as Vice-President of the Anthropological Section in 1887, published in our thirty-sixth volume of Proceedings, the other as retiring President in 1895, published in our forty-fourth volume. In these addresses he had in his usual forcible and comprehensive manner presented his views of American anthropological research and of the aims of anthropology. Dr, Brinton was a man of great mental power and erudition. He was an extensive reader in many languages, and his retentive memory enabled him to quote readily from the works of others. He was a prolific writer, and an able critic of anthropological literature the world over. Doing little as a field archeologist himself, he kept informed of what was done by others through extensive travels and visits to museums. By his death American anthropology has suffered a serious loss, and a great scholar and earnest worker has been taken from our Associ- ation. aus, 1 Address delivered before the American Association for the Advance- ment of Science, at Columbus, Ohio, on August 21, by Prof. Frederic Ward Putnam, the retiring President of the Association. NO. 1558, VOL. 60] In the year 1857 this Association met for the first time beyond the borders of the United States, thus establishing its claim to the name American in the broadest sense. Already a member of a year’s standing, it was with feelings of youthful pride that I recorded my name and entered the meeting in the hospitable city of Montreal, and it was on this occasion that my mind was awakened to new interests which in after years led me from the study of animals to that of man. On Sunday, August 16, while strolling along the side of Mount Royal, I noticed the point of a bivalve shell protruding from roots of grass. Wondering why such a shell should be there, and reaching to pick it up, I noticed on detaching the grass roots about it that there were many other whole and broken valves in close proximity—too many, I thought, and too near together, to have been brought by birds, and too far away from water to be the remnants of a musk-rat’s dinner. Scratching away the grass and poking among the shells, I found a few bones of birds and fishes and small fragments of Indian pottery. Then it dawned upon me that there had been an Indian home in ancient times, and that these odds and ends were the refuse of the people—my first shell-heap or kitchen-midden, as I was to learn later. At the time this was to me simply the evidence of Indian occupation of the place in former times, as convincing as was the palisaded town of old Hochelaga to Cartier when he stood upon this same mountain side more than three centuries before. At that meeting of the Association several papers were read, which, had there been a section of anthropology, would have led to discussions similar to those that have occurred during our recent meetings. Forty-two years later we are still disputing the evidence, furnished by craniology, by social institutions and by language, in relation to the unity or diversity of the existing American tribes and their pfedecessors on this continent. Those were the days when the theory of the unity of all American peoples, except the Eskimo, as set forth by Morton in his ‘‘ Crania Americana ” (1839), was discussed by naturalists. The volumes by Nott and Gliddon, ‘‘Types of Mankind” (1854) and ‘‘Indigenous Races of the Earth” (1857), which contains Meigs’ learned and instructive dissertation, ‘‘ The Cranial Characteristics of the Races of Men,” were the works that stirred equally the minds of naturalists and of theologians regarding the unity or diversity of man—a question that could not then be discussed with the equanimity with which it is now approached. The storm caused by Darwin’s ‘Origin of Species”? had not yet come to wash away old prejudices and clear the air for the calm discussion of theories and facts now permitted to all earnest investigators. Well do I remember, when, during those stormy years, a most worthy Bishop made a fervent appeal to his people to refrain from attending a meeting of the Association then being held in his city, on account of what he claimed to be the atheistic teachings of science. Yet ten years later this same venerable Bishop stood before us, in that very city, and invoked God’s blessing upon the noble work of the searchers for truth. At the meeting of 1857 one of our early presidents, the honoured Dana, read his paper entitled ‘‘ Thoughts on Species,” in which he described a species as ‘‘a specific amount or con- dition of concentrated force defined in the act or law of creation,” and, applying this principle, determined the unity of man in the following words :— ‘We have therefore reason to believe, from man’s fertile in- termixture, that he is one in species; and that all organic species are divine appointments which cannot be obliterated unless by annihilating the individuals representing the species.” Another paper was by Daniel Wilson, recently from Scotland, where six years before he had coined that most useful word ** prehistoric,’ using the term in the title of his volume, ‘* Pre- historic Annals of Scotland.” In his paper Prof. (afterwards Sir Daniel) Wilson controverted the statement of Morton that there was a single form of skull for all American peoples, north and south, always excepting the Eskimo. After referring to the views of Agassiz, as set forth in the volumes of Nott and Gliddon, he said, ‘‘ Since the idea of the homogeneous physical characteristics of the whole aboriginal population of America, extending from Terra del Fuego to the Arctic circle, was first propounded by Dr. Morton, it has been accepted without question, and has more recently been made the basis of many widely comprehensive deductions. Philology and archzeology have also been called in to sustain this doctrine of a special unity of the American race ; and to prove that, notwithstanding 452 NATURE [SEPTEMBER 7, 1899 some partial deviations from the prevailing standard, the American Indian is essentially separate and peculiar ; @ race distinct from all others. The stronghold, however, of the argu- ment for the essential oneness of the whole tribes and nations of the American continents is the supposed uniformity of physio- logical, and especially of physiognomical and cranial character- istics; an ethnical postulate which has not yet been called in question.” After a detailed discussion of a number of Indian crania from Canada and a comparison with those from other parts of America, as described by Morton, he makes the following statements :—‘‘ But, making full allowance for such external influences, it seems to me, after thus reviewing the evidence on which the assumed unity of the American race is formed, little less extravagant to affirm of Europe than of America, that the crania everywhere and at all periods have conformed, or even approximated, to one type.” “* As an hypothesis, based on evidence accumulated in the *¢Crania Americana,” the supposed homogeneity of the whole American aborigines was perhaps a justifiable one. But the evidence was totally insufficient for any such absolute and dog- matic induction as it has been made the basis of. With the exception of the ancient Peruvians, the comprehensive general- isations relative to the southern American continent strangely contrast with the narrow basis of the premises. With a greater amount of evidence in reference to the northern continent, the conclusions still go far beyond anything established by absolute proof; and the subsequent labours of Morton himself, and still more of some of his successors, seem to have been conducted on the principle of applying practically, and in all possible bearings, an established and indisputable scientific truth, instead of testing by further evidence a novel and ingenious hypothesis.” At the close of this instructive paper are the following words: ** Tfthese conclusions, deduced from an examination of Canadian -crania, are borne cut by the premises and confirmed by further investigation, this much at least may be affirmed: that a marked difference distinguishes the northern tribes, now or formerly occupying the Canadian area, in their cranial con- formation, from that which pertains to the aborigines of Central America and the southern valley of the Mississippi; and in so far as the northern differ from the southern tribes, they approx- imate more or less, in the points of divergence, to the charac- teristics of the Esquimaux: that intermediate ethnic link between the Old and the New World, acknowledged by nearly all recent ethnologists to be physically a Mongol and Asiatic, if philo- logically an American.” The third paper of the meeting to which I shall refer was ‘by another of our former presidents, the then well-known | student of Indian institutions and the author of the ‘‘ League of the Iroquois” (1851). In this paper, on ‘‘ The Laws of Descent of the Iroquois,” Morgan discusses the league as made up of five nations, each of which was subdivided into tribes, and he explains the law of marriage among the tribes, the family relationship and the descent in the female line, as essential to the maintenance of the whole system. He then says :— “Now the institutions of all the aboriginal races of this conti- nent have a family cast. They bear internal evidence of a common paternity, and point to a common origin, but remote, both as to time and place. That they all sprang from a common mind, and in their progressive development have still retained the impress of original elements, is abundantly verified. The Aztecs were thoroughly and essentially Indian. We have glimpses here and there at original institutions which suggest at once, by their similarity, kindred ones among the Iroquois and other Indian races of the present day. Their intellectual characteristics, and the predominant features of their social con- dition, are such as to leave no doubt upon this question ; and we believe the results of modern research, upon this point, concur with this conclusion. Differences existed, it is true, but they were not radical. The Aztec civilisation simply exhibited a more advanced development of those primary ideas of civil and social life, which were common to the whole Indian family, and not their overthrow by the substitution of antagonistic institutions ” After calling attention to the fact that a similar condition exists among certain peoples of the Pacific Islands, he writes :— ““ Whether this code of descent came out of Asia or originated upon this continent is one of the questions incapable of proof ; and it must rest, for its solution, upon the weight of evidence, NO. 1558, VOL. 60] or upon probable induction. Its existence among American races, whose languages are radically different, and without any traditional knowledge among them of its origin, indicates a very ancient introduction, and would seem to point to Asia as the birth-place of the system.” It would be interesting to follow the succeeding meetings of the Association, and notethe recurring presentation of views which the quotations I have given show to have been most seriously discussed over a generation ago. An historical review of the literature of American anthropology during the present century would also be interesting in this connection. It is probable, however, that a review of this literature for the first half of the century would reveal the fact that the writers, with here and there a notable exception, were inclined to theorise upon in- sufficient data, and devoted little time to the accumulation of trustworthy facts. The presentation and discussion of carefully observed facts can almost be said to have begun with the second half of the century, and this is the only part of the subject that now commands serious attention. A reference to the very latest 7ésaé of this subject as presented in the ‘* History of the New World called America,” by Edward John Payne (vol. ii., Oxford, 1899), is instructive here. In this volume Mr. Payne admits the great antiquity and unity of the American tribes, which he considers came from Asia in pre-Glacial and Glacial times, when the north- western corner of America was connected with Asia, and when man ‘‘as yet was distinguished from the inferior animals only by some painful and strenuous form of articulate speech and the possession of rude stone weapons and implements, and a know- ledge of the art of fire-kindling. Such, it may be supposed, were the conditions under which man inhabited both the old and the new world in the paleo-ethnic age. . . . Even when a geological change had separated them (the continents), some intercourse by sea was perhaps maintained—an intercourse which became less and less, until the American branch of humanity became practically an isolated race as America itself had become an isolated continent” (Preface). Mr. Payne discusses the growth of the languages of America, the various social institutions and arts, and the migrations of these early savages over the continent, north and south, during the many centuries following, as one group after another grew in culture. He considers all culture of the people autochthonous. In writing upon the physical characters of the people, he says, “ eee Notes: (Z//astraledi\yn pis). - e Our Astronomical Column :— Holmes’:Comet 1899@ (1892 III.) . ...... . 442 The New Algol Variablein Cygnus .......-. 442 Harvard College Observatory. . . . . . «++ = + 442 Torsion-Structure in the Alps. (///ustrated.) . By Dr. Maria M, Ogilvie. .... Sic ces. 3 eae 443 The Motion of a Perfect Liquia. (Zilustrated.) By Prof: 1H. S.HelesShiawaebe ease cis. o-0. Gneme 446 A Problem in American Anthropology. By Prof. Frederic Ward Putnam... . Ro c.f CESS University and Educational iaeieence oe ES Scientific Serials.) (jp giewemeewei= 0 MEMS) Societies'and Academiesmssiene= « «>. « -memeEEa50 457 NATURE THURSDAY, SEPTEMBER 14, 1899. THE CORRESPONDENCE OF HUYGENS. Guzres completes de Christiaan Huygens publides par la Société Hollandaise des Sciences. Tome Huitiéme. Correspondance 1676-1684. Pp. 629. 4to. (La Haye: Nijhoff, 1899). | Eb esate a year after the seventh volume of Huygens’ correspondence the eighth one has made its appearance. As it embraces nine years, and Huygens only lived ten years longer, we may expect that the ninth volume will be the last one devoted to his correspondence. The objection which we made a year ago to the many comparatively uninteresting private letters which have contributed so much to the huge extent to which this collection has grown, applies equally to the present volume. No doubt Huygens was very glad to get the pleasant, gossiping letters from his sister Susanna, who kept him up to what was going on in Holland during his stay in Paris, but posterity will hardly be equally grateful to the far too conscientious editors who have considered it a duty to insert them among Huygens’ “ GEuvres completes.” One feels momentarily almost kindly disposed towards the niece of Peiresc, who ruthlessly destroyed ten thousand letters found after him. Having suffered from ill-health for some months, Huygens left Paris for the Hague in the summer of 1676. In the autumn of the following year he wrote to Colbert to apologise for not coming back that winter owing to his health, but it appears from a letter to his brother Constantin that this was a mere excuse. To his absence from Paris at this particular time we owe some very interesting letters, exchanged between him and Roemer about the latter’s discovery of the gradual pro- pagation of light. Huygens had to return to Paris in the summer of 1678, as he did not wish to lose his French pension, but in 1681 he bade a final farewell to Paris and established himself in his native country. It has been generally supposed that he and Roemer (who had left the French capital a few months before him) were induced to do so by the feeling that Protestants were about to have a bad time in France, though as a matter of fact the edict of Nantes was not repealed till four years later. No doubt this feeling may have had some- thing to do with their departure, but we learn from his correspondence that Huygens did not debar himself from returning, but kept a door open by writing from time to time to Colbert, and after his death to Louvois, regretting that the necessity of being near skilful work- men prevented him from returning yet, and expressing the hope that his pension might not be finally withdrawn. Doubtless he spoke his mind more honestly when he wrote to Constantin (September 1682) that he had no intention of living in France, partly on account of the three illnesses he had suffered from there, “and also for other reasons,” but that he wanted to try to get some part of his pension without living in France. From the very last letter in the volume we see that he was in December 1684 still pegging away at Louvois, but the Minister of War of Louis XIV. no doubt considered that NO. 1559, VOL. 60] money was too scarce to be spent on a foreign philo- sopher. The skilful workmen, whom Huygens wanted in 1681 were required for the completion of his planetary machine, by which he claimed to represent the motions in the solar system with considerable accuracy. Huygens was very proud of the performance of this machine, which is still preserved at the Leiden Observatory, and in letters to Colbert and others he repeatedly lays stress on its superiority to the machine for the same purpose con- structed by Roemer, which is also still in existence, in the “Round Tower” at Copenhagen, on the top of which the observatory was formerly situated. While working at this machine Huygens also wrote to Paris that he was. engaged in the perfection of time-keepers for finding the- longitude, and that he did so at the instance of the East India Company, but we hear nothing further about this. matter. After his return to Holland he and Constantin resumed their investigations on the best methods of polishing lenses for telescopes, and in a number of letters they exchanged their ideas as to the proper construction of polishing machines, &c. In 1684 Christian Huygens. published his “ Astroscopia compendiaria,” in which he described his method of using very long telescopes with- out tubes, keeping the eye-piece in the optical axis of the object-glass by means of a long string which connected two rods attached one to each. Ina letter dated June 5,, 1684, J. D. Cassini makes the very remarkable suggestion that the object-glass might be moved by a monster clock moving in the plane of the equator, on which for the hand was substituted a perpendicular plane to which the lens might be attached according to the declination of the star. We believe this to be the earliest suggestion of an equatorial moved by clockwork. On the other hand, Perrault, a month later, sent Huygens a design of a hori- zontal telescope into which the light from the star was thrown by a mirror kept in the proper position by an assistant, who pointed to the star with a small altazimuth tube connected with the mirror by a system of pulleys. He also sent a similar design by a certain Boffat. It is interesting to see that the horizontal telescope has been: proposed so long ago. During the period (1676-84) covered by the present volume several discoveries of the highest importance were given to the world, especially the discovery of the differential calculus by Leibnitz, but the communications, exchanged between him and Huygens on this subject have already been printed in the collections of Uylen- broek and Gerhardt. Quite new, on the other hand, are the letters on Roemer’s discovery of the gradual pro- pagation of light, only the two first of which have been printed before (in Horrebow’s “Opera mathematico- physica,” T. iil. pp. 126-127, apparently not noticed by the editors). In reply to an inquiry from Huygens, who had seen in the Phz/. Trans., No. 136, a short account of Roemer’s paper (laid before the Academy on November 22, 1676), Roemer informed him, under date September 30, 1677, that Picard acknowledged the reality of the discovery, but that Cassini did not, as only the first satellite of Jupiter showed the phenomenon. Roemer explained this by pointing out that the occultations of the outer satellites were less frequent, the moments of their occultations less sharply observable owing to the: Xx 458 slower motion and to their generally entering the shadow more obliquely; their inclinations and nodes were less accurately known, while it was well known that the motions of the outer satellites differed in a very irregular manner from Cassini’s tables by amounts much larger than that dealt with in the case of the first satellite. The deviation in question was neither a function of the anomaly of Jupiter nor of that of the earth, nor of the configuration of the satellites, but solely of the distance from the earth. Writing to Colbert shortly afterwards, Huygens calls the discovery a most important one, in the confirmation of which the Royal Observatory would be worthily employed, and he adds that he was all the more pleased, as he had himself already, by means of this hypothesis, demonstrated the laws of the double refraction in Iceland spar. To Roemer he wrote that Cassini’s objection did not trouble him much, as long as there were not better ephemerides of the outer satellites available. He doubted that observations of the surface- markings of Jupiter would be of any use in this inquiry, as they could not be accurate enough; but this Roemer did not acknowledge, since the time of passage of a spot across the central meridian could be fixed within two minutes. In a subsequent letter and in a com- munication to the Academy (which does not seem to have been printed before), Roemer proudly gives observ- ations of a spot of September and December 1677, the comparison of which with an assumed value of the period of rotation seemed to exhibit the phenomenon beautifully. Of much greater interest is a remark made by Roemer in a letter dated December 30, 1677, in which he points out that the motion of the earth must affect the apparent direction of the path of light! In Cartesian language, he expresses this by saying that the circular motion of the terrestrial vortex must produce a curvature of the path, and he ingeniously suggests that the amount of this deflection might be determined by selecting two stars in the zodiac, nearly opposite each other, and ob- serving their angular distance apart, first when one was at its heliacal rising, and again four or five months later when the other approached its heliacal setting. The difference would be four times the amount of the de- flection, or, as we should say, four times the constant of aberration. It is very remarkable that Picard, Roemer’s teacher and friend, should have discovered the changes in the place of the pole-star due to aberration (and also those due to nutation, though not the laws which regulate either—see his “‘ Voyage d’Uranibourg,” article viii.), while Roemer logically concluded from his discovery of the velocity of light that there ought to be aberration of light. But it was reserved for Bradley to publish both the Jaws and the theory of aberration. These facts become still more curious when we reflect that, but for the unfortunate destruction by fire of almost all Roemer’s observations— which had been made with instruments constructed on novel principles not adopted elsewhere till much later, the foundation of modern astronomy might have been built on them and not on Bradley’s observations. It was indeed unfortunate that Roemer published so very little about his scientific labours, and it is therefore par- ticularly interesting to get a slight insight into them through his correspondence with Huygens. NO. 1559, VOL. 60] NATURE [SEPTEMBER 14, 1899 Among other matters dealt with in this volume we may mention the controversy on the theory of the centre of oscillation between Huygens and Abbé de Catelan, a man whose aim in life seems to have been to object to every new mathematical publication and to exhibit his inability to grasp any new theory. In Vol. i. of Huygens’ “ Opera varia,” the papers written by the two opponents, as well as by Jacques Bernouilli, who took Huygens’ part, have already been printed side by side ; but it is interesting to see from the correspondence that Catelan’s attack was slyly inserted in the Amsterdam reprint of the Journal des Scavans, although it had not appeared in the original Paris edition. The volume contains as frontispiece a plate reproduc- ing a fine medallion of Huygens from 1679, and another showing a medal apparently struck in his honour in the same year. It is announced that his unpublished works are to appear in the volumes following immediately after those devoted to his correspondence. J. L. E. DREYER. METAPHYSICS OF BIOLOGY. The Living Organism: an Introduction to the Problens of Biology. By Alfred Earl, M.A. Pp. xiii+ 271. (London : Macmillan and Co., Ltd., 1898.) HE observer of the more recent phases of biological thought will not need to be told that during the last few years a reaction has been setting in, both in England and abroad, against any so-called mechanical theories of the origin and development of living things, and against any hypothesis which seeks in the facts of chemistry and physics for an ultimate explanation of the phenomena of life; and those who have had the oppor- tunity of a more intimate acquaintance with this new philosophical development will know that the “neo- vitalist”” adopts, as the basis of his scientific beliefs, an ontology which states that it is not true that the hierarchy of the natural sciences presents us with a material universe of which the separate parts studied by the several sciences can all be ultimately expressed in terms of one of them, biology in fact being a special case of chemistry, this of physics and so on; but that on the contrary every science deals, not with a part, but with the whole of the material universe, all the facts of which come under its survey, and asa particular manner of looking at which it is to be regarded. On this view, therefore, it is as useless ever to expect a physical explanation of the chemical atom as it is futile to hope that organic meta- bolism may after all turn out to be merely a specially complex chemical reaction: each science has what is, for itself, an ultimate fact, in terms of which it seeks to express the whole of nature, but which has nothing in common with the ultimate fact of any other science whatever. This ultimate fact is, for the vitalistic bio- logist, the living organism, and when pressed for an account of how the inanimate world is included in his science, he replies by a reference to the environment, which, we are told, is to be regarded as being made by and for the organism itself. Now it may be that the ontology which includes, with Kant, all phenomena in but a single category is obsolete, SEPTEMBER 14, 1899] as these philosophers suggest, and that we must rather, with Hegel, look upon the universe from several points of view, though even Hegel, if we are not mistaken, would have made the various categories develop out of one another; but whether that be so or not, and how- ever impossible it is at present to point to any scientifically complete demonstration of the correctness of the opposite hypothesis, it is necessary to inquire very carefully into the positive basis on which this revived vitalism, of which the present volume is an exposition, rests. Starting with sundry somewhat loosely connected re- marks on the nature of knowledge in general, and the method of biology in particular, the author, after giving a brief account of the functions of assimilation and repro- duction in the living organism, touches, in a chapter on the relation of that organism to its surroundings, the key- | note of his whole system. Since, we are told, the human organism is a knowing subject, the organism in general is to be regarded as not only object but also as subject ; and hence all mechanical, or physical, or chemical explanations of organic function are and must ever be inadequate, because they take no account of that in- explicable residuum, the “ spontaneous choice” or “ selec- tion,” the “subordination to a purpose” which an organ- ism displays in every function it performs, and most obviously of all in sensation, the act which puts it in immediate communication with its environment. Now such a view as this seems to us to be pervaded by a most vicious anthropomorphism, due to an -unfor- tunate confusion between the organism, or its nervous system, to which those parts of the phenomenal world | outside it are related during the act of knowledge, on the one hand, and on the other the metaphysical ego or sub- ject of knowledge. For knowledge is most certainly not, as the author seems to imagine (for he tells us that know- ledge is part of the subject-matter of biological science) a relation between the organism and its environment, both of which are phenomenal, that is to say are events occurring in space and time, but a relation between phenomena and a timeless and spaceless noumenon, with which metaphysics alone is concerned, but with which science has nothing to do at all. The endeavour to locate in the organism, regarded as matter for scientific inquiry, a ‘‘ subjective” residuum is apt to remind one of the now discredited search for that metaphysical phantom, the “thing-in-itself,” and it is incumbent upon biology, advancing along rigidly deter- “freedom of the will” which psychology cannot allow for the human organism, under the name of “spontaneous selection,” to the purely objective phenomena exhibited | in organic function. There are, indeed, no grounds either in theory or in fact for regarding the organism as anything else but the transitory product of certain causes which it is the aim of the biologist to discover. When Mr. Earl speaks of constant form under an ever-changing material, he momentarily forgets the dominant fact of the evolution of form ; and to whatever causes we assign this evolu- tion, its existence is beyond a doubt; and when he speaks of the impossibility of applying quantitative con- ceptions to organic phenomena, he either ignores or is NO. 1559, VOL. 60] NATURE | 459 ignorant of certain recent work in this direction, in which, indeed, alone lies a hope for the progress of biology as a science. Serious though the misconceptions seem to us to be which mar this essay, apart from certain minor details of arrangement to which exception might possibly be taken, and the mistake of discussing epistemological problems in a book apparently intended for beginners, we may at least hope that it will serve to convince those who may still be in doubt of the futility of attempting to apply to the living organism, which, like the subject-matter of any other science, should be studied from a strictly zeti- ological point of view, teleological conceptions which have not even a place in human psychology. Not that it is therefore to be supposed that when the sciences have said all they have to say our knowledge of the universe is at an end: the last word must always remain with metaphysics, in which those ideas of ‘ freedom” and the “‘final cause” which science cannot accept may find their true proportions ; for metaphysics looks upon the universe not merely as a continuous time-process, | but as a whole, time and space being only the forms under which phenomena appear to a transcendental subject, in which the ultimate interpretation of them is to be sought, but which it is as fatal for metaphysics as it is for | science to confound with the living organism. OUR BOOK SHELF. An Account of the Deep-Sea Ophiuroidea collected by the Royal Indian Marine Survey Ship “ Investigator.” By R. Koehler. (Calcutta: 1899.) | THIS monograph, published by erder of the Trustees of the Indian Museum, is well worthy its predecessors, now famous, and adds one more to the brilliant results of the /nvestigator, memorably associated with the names of Dr. A. Alcock, its editor, now superintendent of the Indian Museum, and his indefatigable co-workers in the Zoology of the Indian Seas. It is chiefly devoted to the description of forty species of Ophiurids which are new, the majority of the larger number obtained during the cruises of the ship having been already re- ported upon by Prof. Koehler in the Annales des Sciences Naturelles, as explained in the text. The new forms are of the genera Ophizacantha (7 species), Amphiura (5 sp.), Ophioglypha (4 sp.), Ophiomustum, Ophiactis, Ophiochiton, Ophiomitra, and Gorgonocephalus, each 2 sp., and thirteen other genera each 1. Interest chiefly centres in a new genus, Opfzotypa, obtained in the Gulf of Bengal at 1997 fathoms. O. szmplex is the name by ministic lines, to resist any attempt to transfer that | which the author would have it known, its special struc- tural peculiarity being the great size of the primary plates of the disc, the aboral region of which is beset by an enormous pentagonal centro-dorsal and five equally large radials, separated by small but regular inter-radials. Interbrachial plates are present on the ventral face. Radial shields are absent, and the author, regarding this | character and the small number of plates present in the disc of the adult as primitive, proceeds to a comparison with the young stages of Amphiura, as described by Ludwig and Fewkes, which would seem to justify the conclusion that Opfzotypfa, as regards its skeleton, may be a persistently embryonic form. The monograph is elaborately illustrated by fourteen | exquisite plates, photo-etched from the author’s drawings at the Survey of India Offices in Calcutta, and on perusal of its contents the mind reverts to the interesting series | of Astrophiurids, whose “ primary larval plates” and 460 NATURE [SEPTEMBER 14, 1899 growth stages were in 1884 described and discussed by Sladen, and conjures up theories of stalked-ancestry, pentameral symmetry, and the like. Whatever the significance of the facts, this beautiful report comes to us at an opportune moment, @ propos of the issue of the magnificent series of “Illustrations,” delineating the many novel forms discovered and described by Dr. Alcock and his co-workers in the Indian seas during the last nine to ten years. He has shown by his own share of the work that it is possible for one man, new to the task of marine investigation, to successfully handle taxonomically groups so dissimilarly ordained as the Bony Fishes and Echinoderms, to say nothing of his sterling work upon the “Carcinological Fauna” of the area. An achievement this of which he may well be proud. The Annals and Magazine of Natural History and Journal of the Asiatic Society of Bengal for the period named teem with his original communications, and to him, to Commanders Carpenter, Hoskyn, and Oldham, to Dr. A. S. Anderson, who has more recently taken up the work, their collaborators, assistants, and native artists, we tender our hearty congratulations upon the skill and persistent patient enthusiasm with which they have so long and so successfully continued their task. Work thus performed is always durable, and that of H.M. Survey ship Jzvestigator will be ever con- spicuous among post-Challengerian explorations of the deep sea. We close the report with a feeling of gratitude to all concerned in its production. LETTERS TO THE EDITOR. (Zhe Edvtor does not hold himself responsible for opinions ex- pressed by hts correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts tntended for this or any other part of NATURE. No notice is taken of anonymous communications. | Dark Lightning. I HAVE been greatly interested by some photographs showing the rare phenomenon of dark lightning, which have recently been sent to me. So far as I know the only explanation that has ever been offered to account for them is photographic reversal, due to extreme brilliancy. This appears to me to be wholly out of the question for two reasons. In the first place, a dark line on the picture, resulting from Over-exposure of a very brilliant line, would be surrounded by bright edges due to the lesser photographic action in the halation region. This is never present so far as I know, the dark flashes being minute black lines ramifying from, or in the neighbourhood of, the main discharge. Secondly, from what evidence I can gather, the dark parts of the flash are not those which appear most brilliant to the observer. Mr. Jennings, of Philadelphia, who in 1890 secured a remarkable picture (reproduced in Photog. Times Annual, 1891) showing a very brilliant flash with countless dark flashes covering the sky around it, tells me that the appearance to the eye was a brilliant white discharge, with fainter rose-coloured ramifications, the latter developing in the negative, or rather positive, as dark flashes. Some years ago it occurred to me that a dark flash might be produced by a3preponderance of infra-red radiations, which, as Abney has shown, undo the work of ordinary light on the plate. If we had a form of discharge capable of giving off very little actinic light, and an abundance of infra-red light, it might come out dark on a feebly illuminated background. This is of course a very wild guess, with nothing to substantiate it ; but the dark flash appears to be a reality, and a poor hypothesis is perhaps better than none at all. I have recently thought that the phenomenon might perhaps be explained in another way. We have a flash which appears darker than the sky behind it. It is inconceivable that the discharge could render the air in its path opaque, in the ordinary sense, to white light. But the NO. 1559, VOL. 60] light which illuminates the sky, in the case®of these pictures, is not daylight, but light coming from another flash, that is made up of wave-lengths corresponding to the periods of vibration of the dissociated matter in the path of the discharge. Now, may it not be possible that in the dark flash we have a discharge, weak or nearly wanting in actinic light, which, however, renders the air in its path capable of absorbing to some extent the radiations of the wave-lengths which come from the bright flash ? Such a flash might possibly appear dark on a background feebly illuminated by light, exclusively of these wave-lengths. In other words, may wenot have in the path of the dark flash dissociated molecules, radiating but feebly, and capable of taking up vibrations of periods similar to their own, coming originally from a simultaneous brighter discharge ? It might not be impossible to reproduce the phenomenon by photographing a spark in front of a light background. Sparks are almost always taken against a black background, which would account for the absence of dark flashes in pictures of arti- ficial discharges. A heavy main spark with lateral branches would seem the most suitable kind to employ. The best method of attacking the problem experimentally, it seems to me, would be a search for selective absorption in a partially exhausted tube. If the source of light were continuous, any absorption would be unnoticeable, unless persisting for some time after the dis- charge (which is unlikely), for the time between successive discharges is great in comparison to the actual duration of one of them. Even in the case of so-called continuous discharges produced by high potential batteries, the discharge is often, and may always be, intermittent in character. The source of light should then be of no longer duration than the discharge occurring in the gas the absorption of which is to be examined. Ican think of no way of producing a white or continuous spectrum source of as snort duration as, and contemporaneous with, the discharge in the tube, but by employing two tubes dif- ferently excited, the one as a light source, the other as an ab- sorption tube, some results might be obtained. Prof. Trowbridge found that an argon tube emitted a blue light or red light according to whether it was illuminated by means of an oscillatory or non-oscillatory discharge. By using the blue tube as the source of light and the red tube as the absorption tube, the two being arranged so as to be illu- minated simultaneously, it might be found that the red tube had the power of absorbing, to some extent, the blue radiations from the other. Ihardly think results would be obtained, but the experiment seems worth trying. A picture taken by Mr. H. B. Lefroy, of Toronto, sent to me by Mr. Lumsden, Secretary of the Astronomical and Physical Society of Toronto, has some very curious appearances. There is an exceedingly brilliant flash running down the centre of the plate, illuminating the sky quite brilliantly in its neighbour- hood. In its immediate vicinity, though not joined to it in any way, are innumerable dark, thread-like markings, which in places seem to cross each other, forming meshes. Mr. Lumsden assures me that the testimony of all photographic experts who have seen the plate is to the effect that markings of that description could only be produced in the exposure—that is, they are not due to faults in the film or the results of imperfect development. The fact that they are found only in the immediate vicinity of the bright flash is additional testimony in the same direction. These markings are wholly different from any that I have seen, not having the form of branched flashes. Something in their re- semblance to photographs of sound-waves started by a spark, which I have recently made (see P2z/. A/ag. for August), sug- gested to me that they might possibly be due to the illumination of the sound-wave due to a powerful discharge by a second dis- charge. Under ordinary conditions, that is, with a uniformly illuminated background, such waves would of course be in- visible, but conditions might possibly arise due to the proximity of black clouds under which they might show—a sort of “Schlieren Methode” on a large scale. I have not attempted yet to plan an arrangement of clouds, which, by acting as screens to light coming from certain directions, might render visible a region of the air in which the optical density underwent a rapid change. Mr. Lumsden’s picture shows very black clouds irregularly distributed and in close proximity to the flash. SEPTEMBER 14, 1899] NATURE 401 The idea of a photograph ofa thunder wave is a pleasing fancy, at all events. It seems to me that it will be impossible to formulate even a reasonable guess as to the cause of these dark flashes until a good many pictures are brought together for comparison, and as much testimony as possible secured as to the appearance of the flashes to the eye. Personally I have seen very few of the pictures, and never the original negative. My intention in writing this letter is not so much to advance theories accounting for the phenomenon of the dark-flash as to reawaken an interest in the subject, and bring out ideas from persons qualified to treat the matter. Madison, Wisconsin, U.S.A. R. W. Woop. Tides in the Bay of Fundy. In the last report of Mr. W. Bell Dawson on the Survey of Tides and Currents in Canadian Waters, the results are given of an investigation of the tides in the Bay of Fundy. The inform- ation in Mr. Dawson’s report is interesting, as these tides are frequently credited as having the greatest range of any in the world, and in some books of physical geography are stated as having a range of 120 feet,4 or more than double that which actually prevails. As a matter of fact the range of the tides in the Bay of Fundy does not exceed that which occurs in the Bristol Channel, where the extreme recorded difference between high and low water at Chepstow is 53 feet, being the same as the “Saxby,” or record tide in the Cumberland Basin, Nova Scotia. The cise above the mean level of the sea in both cases is about the same, or from 22 to 23 feet. In the Bay of Fundy the range varies considerably at different localities. Outside the bay at Portland on the north side the range is 9} feet, and at Cape Sable on the south side $3 feet. In the Atlantic, on the south side of Nova Scotia, the range is from 6 to 7 feet. At the mouth of the bay at Yarmouth the range is 16 feet, and at Seal Island 18 feet. Further up, at Digby, on the south side, and St. John on the north, it increases to 27 feet. Where the bay divides above Black Rock the range is 36 feet. In the Minas Basin it varies from 41 feet at Parsboro to 48 feet at florton Bluff and 504 feet at Noel Bay. In the Chignecto Channel in Cumberland Bay the range is 454 feet. From observations obtained by tide gauges fixed at different stations, and information collected in the localities, Mr. Dawson gives the range of spring tides as follows. The highest recorded tide is known as the ‘‘Saxby tide,” which occurred in 1869. The low water mark for that tide is mot given, but taking the lowest low water level recorded, the range of that tide in Cumberland Bay was 52°80 feet; the ordinary spring tide range there being 45°80 feet. The Admiralty tide tables give this as 45} feet. At Moncton, the Saxby tide rose above the lowest recorded level, 38°34 feet; the next highest recorded tide being in 1887, 31-91 feet. An ordinary spring tide rises 30°25 feet above mean low water of spring tides. The Admiralty tide tables give the range at Moncton Railway as 47 feet. Mr. Dawson points out that this is misleading, this range being that above low water at the mouth of the river, from which the low water line has a considerable inclination towards the head of the estuary. At Parsboro, in the Minas Basin, the ordinary spring tide range is 41 feet, and the extreme 47 feet ; the Admiralty tide tables giving the ordinary range as 43 feet. Mr. Murphy, the Provincial Engineer of Nova Scotia, in a paper contributed in 1867 to the Institute of Natural Science, on the tides in the Bay of Fundy, gave the range of spring tides at the head of the bay as 22 feet above mean sea level, and as varying from 50 to 60 feet above extreme low water. Having a few years since to report on some proposed em- bankment works in the Bay of Minas, I made inquiries in the locality from those best able to furnish me with information as 1JIn Sir J. F. Herschell’s ‘‘ Physical Geography of the Earth,” fifth edition, 1875, it is stated that: “In the Bay of Fundy the tide not uncom- monly rises 50 feet, and, as is said, on some occasions to more than double this height.'* Robinson, in his ‘* Mechanical Philosophy,” in the article on Tides, says, “‘In the Bay of Fundy, in the harbour of Annapolis Royal the tide rises 120 feet.’ NO. 1559, VOL. 60] to the rise of the tides there, and came to the conclusion that at Horton the greatest range to be dealt with was 48°50 feet. The difference in the range of the tides in Cumberland Bay, at the head of the Bay of Fundy, and in Verte Bay, North. umberland Straits, in the Gulf of St. Lawrence, is worth recording. The length of the isthmus which separates the two bays along the line of the proposed Chignecto Ship Railway is eighteen miles. The range of ordinary spring tides on the one side of this neck of land is 45°80 feet, and of the highest known tide 52°80 feet; and on the other side 13°40 feet and 560 feet respectively, the mean level of the sea being only 0°26 feet higher in the Cumberland Bay than in Bay Verte. It is interesting to compare the tides in the Bay of Fundy with those in the Bristol Channel. At Bude Haven and Pem- broke, at the mouth of the Channel, the rise of an ordinary spring tide is 23 feet ; at the mouth of the Avon it is 4o feet ; at Chepstow the range is 50 feet, and in extreme tides 53 feet, the rise above the mean level of the sea being 233 feet. From levels taken across the land from Portishead in the Bristol Channel to Axmouth in the English Channel, with a mean tide rising 354 feet at Portishead and 10 feet at Axmouth, the mean level of the sea was found to be 9 inches higher at the former than at the latter place.! There is a tidal bore in the Bay of Fundy, but it is not so strongly developed as at some other places. It shows itself at Moncton, 19 miles from the mouth of the Petticodiac River, where the estuary consists, at low tide, of mud banks and flats, with a low water channel about 500 feet wide, and having at high water a width of half a mile. The run of the rising tide first breaks into a bore at Stoney Creek, 8 miles below Moncton, and continues to the head of the estuary at Salisbury, 13 miles above, the total dis- tance traversed being 21 miles. Mr. Dawson describes the noise made by the approaching bore as that of a distant train, | which increased to the hissing and rushing sound of broken water. The bore arrived at the point of observation eleven minutes after the sound was first heard, having the appearance of a front of broken and foaming water 2 to 3 feet in height. The mean velocity was 8°47 miles an hour, the maximum being 9°61 miles. The greatest rise of water after the bore passed was 3 feet in ten minutes. The greatest recorded height of the bore is 5 feet 4 inches. The only other place in the bay in which a bore has been observed is in the upper part of Cobequid Bay. W. H. WHEELER. ETHNOGRAPHICAL COLLECTIONS IN GERMANY. (ps2 question of the representation of primitive culture in our national museums is rapidly be- coming an urgent one, not only on account of the growing importance of anthropology, but also because primitive culture itself is disappearing before civilisation. The wild man is dying out or being transformed, and the hours during which we may question him about himself are already limited. Those nations therefore which take the utmost advantage of the opportunities which remain will have something in the nature of a monopoly when primitive culture is actually extinct ; and it is to them that the students of the twentieth century will have to apply for their facts. If her present rate of progress is maintained, Germany will soon have so far distanced all other European countries as to place herself in a position of permanent and unassailable superiority. It cannot therefore but be a matter of importance to cast a glance at the present state of ethnographical museums in Germany, in order that we may form some notion of the relative position of our own. Almost all the large cities in the German Empire possess ethnographical collections, and in such places as Leipzig, Dresden and Hamburg, these are of first-rate 1 ‘*Tidal Rivers.” (Longman’s Engineering Series, 1893.) 462 NATURE [SEPTEMBER 14, 1899 importance. But none of them are in the same class with Berlin, and as it is with Berlin that London ought to measure itself, these short remarks must practically be confined to the German capital. The KGénigliches Museum fur Volkerkunde is a large building completely devoted to ethnographical and pre- historical collections: it has three floors, the lowest devoted to prehistory ; the first to the collections from Africa, Oceania and America ; the second to those from Asia. For administrative purposes it is divided into five departments: the Prehistoric, the African and Oceanic, the American, the Indian, and the Chino-Japanese. Each of these departments has a keeper, who usually has two assistants under him, so that the scientific staff amounts to about twelve men. The museum has an annual grant of 50,000 marks, which is supplemented upon special occasions by the voluntary gifts of a com- mittee of wealthy and patriotic citizens known as the “Hilfskomitée.” The value of this unofficial assistance can hardly be over-estimated. It makes possible the acquisition of exceptionally fine collections when the Government grant is not alone sufficient, as in the case of Benin, and it provides the means of retaining scientific explorers and collectors in outlying parts of the world. The museum can thus command the services of well- instructed investigators, and is in a position to carry out the work of collecting in a systematic and continuous manner. Berlin is probably far less dependent on the dealer and the unscientific collector than we are in London. Altogether the Hilfskomitée appears to be a most admirable institution reflecting the greatest possible credit upon all concerned. The housing of the collections at the Museum fur Volkerkunde is also excellent. In addition to extensive basements and a domed hall with a gallery running round it, there are two large and four smaller rooms on each of the three floors. Most of these are lighted from both sides, the objects being exhibited in large free-standing metal cases with glass shelves, so that none of the speci- mens lie in deep shadow. The wall space between the windows and at the ends of the rooms is thus available for maps and diagrams, of which there are great numbers ; there is also room for numerous “mannikins,” or life- sized models of representatives of various tribes, all care- fully coloured, and dressed and armed in the style of their respective countries. These figures, with excellent models of houses, canoes and other large objects, and with ample and carefully written labels, afford a far more vivid picture of primitive life than can be obtained from books alone. The arrangement of the collections is geographical, but occasionally comparative series, known as ‘“‘Vergleichende Gruppen,” are exhibited; this is | especially the case in the Indian Section. A library and a lecture theatre are important adjuncts to the building, and the latter brings the museum into direct connection with anthropological teaching. This has obvious ad- vantages, for it probably enables the staff to stimulate | the interest in ethnology of many students who after- wards become connected with Colonial administration. Enough has perhaps been said to illustrate the advant- ages which Germany enjoys in the acquisition of ethno- graphical collections and in the dissemination of ethnological knowledge. Compared with our own, her position is very striking. We have no independent ethnographical museum, for at present we can only use for the purpose a section of the Department of British and medieval antiquities at the British Museum. The officials of this Department, with so many other claims upon their attention, cannot be expected to com- pete with the organised staff at Berlin, who concentrate their whole attention on ethnographical studies. Against | continuous and systematic collection we can only set occasional and limited acquisitions. Under such con- NO. 1559, VOL. 60] ' exploitation of a Colonial Empire. ditions, the race between Great Britain and Germany is a race between Argus anda blind man. Nor can we flatter ourselves that we are to be eclipsed by Berlin alone ; for Leipzig is already a serious rival, and Dresden is con- sidering the erection of a new museum of ethnography. In numerous other towns there are abundant signs of activity. If it is asked how it is that the Germans have out- stripped us in this manner, several reasons at once sug- gest themselves. To begin with, the rapid commercial and Colonial expansion of Germany during the last thirty years has been the expansion of the best educated people in Europe. Thus there has been little tendency to regard savage races from the point of view of a popular show, and a widespread capacity to assign to primitive culture its due scientific importance. If this is the attitude of the people as a whole, it is but natural that in officials, travellers and merchants a taste for ethnology is easily awakened. And as these are the classes in which a museum would naturally find its most useful allies, the national collections have greatly benefited by their interest and co-operation. The introduction to the Guide to the Museum fiir V6lkerkunde contains a large proportion of official names in its long list of donors. Naval and military officers, consuls, doctors and adminis- trators, are all conspicuous in their turn. The museum has also enjoyed the support of more exalted personages, for the German Emperors have all given proof of their sympathy upon various occasions. Again, the German museums appear in many respects to be worked more economically than our own. Their hours of closing are early, so that artificial lighting is not required in the galleries ; they are also closed during at least one day in each week, which enables scientific studies to be carried on with the minimum of interruption, and the work of cleaning to be executed by a smaller staff. The fittings are also arranged with less regard for high finish than for practical and serviceable qualities. Finally, the wonderful energy and initiative of the veteran Prof. Bastian must not be forgotten. He has pressed the claims of ethnography with untiring enthusiasm for many years, and has had the reward of living to see the museum which he directs take the first place among the ethno- graphical museums of the world. Comparisons are proverbially odious, and that which one is compelled to draw between Berlin and London is not gratifying to national pride. It is hard to be- lieve that we can continue satisfied with present con- ditions, and sooner or later a change must come. Let all scientific men, whether their immediate in- terests lie in the direction of ethnography or not, lend their sympathy and support to any movement which promises to introduce a new order of things. But the old order must be changed quickly, or it may be too late. Even now it is doubtful whether we can ever make up all the ground which has been lost, for in some parts of the world specimens of primitive art are vanish- ing with such rapidity that complete collections are per- haps unattainable. But a serious effort made at the present time would be crowned at least with a com- parative success; and the first thing to be done is to house in a more satisfactory manner what we already possess. It would surely be desirable to unite under one roof the collections which illustrate primitive culture, and those which illustrate the physical characteristics of the different branches of mankind. Meanwhile it should be freely admitted that we have much to learn from continental nations, for not only Germany but also Holland can give us useful lessons in the ethnographical But Berlin is the model which we should set before our eyes: the frank admission of this fact will be the best preliminary to a more satisfactory state of affairs. SEPTEMBER 14, 1899] WAT URE 463 THE DOVER MEETING OF THE BRITISH ASSOCIATION. ia is hardly yet possible to give anything like an accurate estimate of the number of members likely to be present at the meeting of the Association, but it is probable that there will be at least 1500 visitors. The foreign members of the Association will be well re- presented. Prof. Chappuis, of Paris, will discuss Ther- mometry in Section A. It is likely that Prof. Remsen will pay a flying visit to the meeting. Amongst other Americans who have promised to attend are Prof. Rotch, of the Blue Hill Observatory, Prof. Bauer, of the Magnetic and Geodetic Survey, Profs. Barker, Carl Barus, Campbell, Thurston and Scott. Prof. Calmette, of the Pasteur Institute, may pos- sibly attend, but he is at present engaged on the Plague Commission at Oporto : Prof. Kossel, of Marburg, is with him, but hopes to come to Dover if possible. Prof. Kronecker, of Berne, will be also present, so that the foreign physiologists are well represented. Of foreign chemists, besides those mentioned, are Profs. Ladenburg and Fittig and Georges Lemoine. Geography will be represented by Prof. Hjort, of Christiania; Dr. Gerhard Schott, of the Deutsche Seewarte, who will speak on the results of the Valdivia Deep Sea Exploration; H. Arctowski, who will read a paper on Arctic Exploration ; Admiral Markaroff, of the Russian Navy, will also attend. Abbé Renard, of Ghent, Dr. van Rijckevosel, Prof. Julin, of Liége, Prof. Cyon are a few of the other celebrated foreign men of science who are expected. The question of accommodation of the visitors has reached a very acute stage, if we may judge from the letters which have appeared in various London papers. Dover lodging-house keepers and their agents persist in thinking that the meeting of the Association will permit Ascot week charges to be made. There are lodgings of all kinds to be found at really moderate charges without difficulty, and the local secretaries are willing to do all in their power to assist members to obtain such accommodation. The strongest represent- ations have been made to the agents on the subject, and it is probable that there will be no further difficulties ; but of course it is hard to remove an impression which has got abroad. The installation of the Marconi system of wireless telegraphy has now been made in the Town Hall, and a sufficiently lofty pole has been erected to permit of the direct transmission of messages to Wimereux. It is intended that Prof. Fleming should transmit a message of congratulation on the evening of his lecture to the meeting held at Rome on the same day, and that the reply will reach Boulogne by the ordinary wire, and be transmitted by the wireless system before the meeting terminates. Demonstrations of the Marconi system of telegraphy will take place at the Mayor’s conversazione on Thursday evening. Itis hoped that about 400 of the French men of science will attend the luncheon to members of the French Association on Saturday. Some twenty Belgian geo- logists, who have been visiting London during the past ten days, will also be present. On the occasion of the French visit there will be special facilities for the inspection of the Castle, which will be closed to the general public on the afternoon of Saturday, to permit the military authorities to devote themselves entirely to the members of the British Association and their guests. The details of the foreign tour are all settled. Those who take part in this tour will have every occasion to look back with pleasure upon a very pleasant visit. At most of the towns visited there will be official receptions, with something of a special nature at Brussels on Sunday, September 24. The following details of the work in the Sections, NO. 1559, VOL. 60] omitted from last week’s have now been supplied. In Section C (Geology) the address of the President, Sir Archibald Geikie, will, it is hoped, be delivered on Saturday, September 16, in order that the members of the French Association may be present. The address will deal with matters of equal interest to geologists and physicists. Reports will be presented by a committee appointed at the Toronto meeting to investigate the Pleistocene flora and fauna of Canada ; by a committee which has been securing photographic records of the disappearing drift section at Moel Tryfan ; by the three committees appointed a short time ago to investigate the ossiferous caves at Uphill, near Weston-super- Mare, the Ty-Newydd caves, and the Irish elk remains in the Isle of Man. The report of the committee which has been engaged for some years in collecting photographs of geological interest in the British Isles, will this year be accompanied by that of a similar committee appointed for the same purpose in Canada ; and reports may be expected from other committees on erratic blocks, on life-zones in British carboniferous rocks, and on the registration of type specimens. The chief interest of this Section will, no doubt, centre round the explorations for coal in Kent, and communi- cations on this subject from Prof. Boyd Dawkins and Mr. Robert Etheridge will be awaited with expectation : in connection with this subject Mr. Jukes-Browne pro- mises a paper on a boring made through the chalk at Dieppe in 1898. Many French and Belgian geologists will, it is hoped, take part in the discussion on this and kindred subjects, especially as the Belgian Geological Society is holding a special meeting at Dover during that of the British Association. Among foreign visitors Prof. van den Broeck promises a paper on the Iguano- dons of Bernissart, and Prof. Renard one on the origin of chondritic meteorites. Among papers of local interest will be one by Prof. Boyd Dawkins on the geology of the Channel Tunnel ; one by Dr. Rowe on the Dover chalk; and one by Captain McDakin on coast erosion. Among other papers promised in this Section may be mentioned Prof. Sollas on homotaxy and on contemporaneity, and also on the origin of flint; Mr. Vaughan Cornish on photographs of wave phenomena; Dr. F. Moreno on Neomylodon ; Prof. Watts on the Mount Sorel granite; Mr. G. Abbott on water zones and their influence on concre- tions; Mr. Plunkett on the Fermanagh Caves ; and Dr. Tempest Anderson on the 1898 eruption of Vesuvius. In Section G (Mechanical Science) the programme of papers to be read and discussed is as follows :—Thursday, Presidential Address by Sir William White, K.C.B., F.R.S.; the Dover Admiralty Harbour Works, by W. Mathews ; non-inflammable wood and its use in warships, by E. Marshall Fox. Friday, a short history of the engineering works of the Suez Canal to the present time, by Sir Charles Hartley, K.C.M.G ; fast cross-Channel steamers, by Hon. C. A. Parsons, F.R.S.; the Niclausse water-tube boiler, by M. Robinson; the discharge of torpedoes below water, by Captain Lloyd. Saturday, the erection of Alexander III. Bridge in Paris, by A. Alby (of Paris). Monday, electrical machinery on board ship, by A. Siemens; earth currents from electric tramways, by J. Swinburne ; some recent applications of electro- metallurgy to chemical engineering, by Sherard Cowper Coles ; signalling without contact, a new system of rail- way signalling, by Wilfrid S. Boult. Tuesday, recent experiences with steam on common roads, by J. I. Thornycroft, F.R.S. ; the Dymchurch wall and the re- clamation of Romney Marsh, by E. Case; an instru- ment for gauging the circularity of boiler furnaces and producing a diagram, by T. Messenger ; and the sea lights of the south and south-east coasts of England, including ' the Channel and Scilly Islands, by T. Kenward. article, 464 NATURE [SEPTEMBER 14, 1899 INAUGURAL ADDRESS BY PROF. SiR MICHAEL FOSTER, K.C.B., Sec.R.S., PRESIDENT OF THE ASSOCIATION. He who until a few minutes ago was your President said somewhere at the meeting at Bristol, and said with truth, that among the qualifications needed for the high honour of Presidency of the British Association for the Advancement of Science, that of being old was becoming more and more dominant. He who is now attempting to speak to you feels that he is rapidly earn- ing that distinction, But the Association itself is older than its President ; it has seen pass away the men who, wise in their generation, met at York on September 27, 1831, to found it : it has seen other great men who in bygone years served it as Presidents, or otherwise helped it on, sink one after another into the grave. Each year, indeed, when it plants its flag asa signal of its yearly meeting, that flag floats half-mast high in token of the great losses which the passing year has brought. This year is no exception ; the losses, indeed, are perhaps unwontedly heavy. I will not attempt to call over the sad roll-call ; but I must say a word about one who was above most others a faithful and zealous friend of the Association, Sir Douglas Galton joined the Association in 1860. From 1871 to 1895, as one of the General Secretaries, he bore, and bore to the great good of the Association, a large share of the burden of the Association’s work. How great that share was is perhaps especially known to the many men, among whom I am proud to count myself, who during his long term of office served in succession with him as brother General Secretary. In 1895, at Ipswich, he left the post of General Secretary, but only to become President. So long and so constantly did he labour for the good of the Association that he seemed to be an integral part of it, and meeting as we do to-day, and as we hence- forward must do, without Douglas Galton, we feel something greatly missing. This year, perhaps even more than in other years, we could have wished him tobe among us; for to-day the Association may look with joy, not unmixed with pride, on the realisation of a project in forwarding which it has had a conspicuous share, on the com- mencement of an undertaking which is not only a great thing in itself, but which, we trust, is the beginning of still greater things to come. And the share which the Association has had in this was largely Sir Douglas Galton’s doing. In his Address as President of Section A, at the meeting of the Asso- ciation at Cardiff in 1891, Prof. Oliver Lodge expounded with pregnant words how urgently, not pure science only, but industry and the constructive arts—for the interests of these are ever at bottom the same—needed the aid of some national establishment for the prosecution of prolonged and costly physical researches, which private enterprise could carry out in a lame fashion only, ifat all. | Lodge’s words found an echo in many men’s minds ; but the response was fora long while in men’s minds only. In 1895 Sir Douglas Galton, having previously made a personal study of an institution analogous to the one desired—namely, the Reichsanstalt at Berlin—seized the opportunity offered to him as President of the Association at Ipswich to insist, with the authority not only of the head for the time being of a great scientific body, but also of one who himself knew the ways and wants at once of science and of practical life, that the thing which Lodge and others had hoped for was a thing which could be done, and ought to be done at once. And now to-day we can say it has been done. The National Physical Laboratory has been founded. The Address at Ipswich marked ‘the be- ginning of an organised effort which has at last been crowned with success. A feeling of sadness cannot but come over us when we think that Sir Douglas Galton was not spared to see the formal completion of the scheme whose birth he did so much to help, and which, to his last days, he aided in more ways than one. It is the old story—the good which men do lives after them. Still older than the Association is this nineteenth century, now swiftly drawing to itsclose. Though the century itself has yet some sixteen months to run, this is the last meeting of the British Association which will use the numbers eighteen hundred to mark its date. The eyes of the young look ever forward; they take little heed of the short though ever-lengthening fragment of life which lies behind them; they are wholly bent on that which is tocome. The eyes of the aged turn wistfully again and again to the past; as the old glide down the inevitable slope their present becomes a living over again the life which has gone before, and the future takes on the shape of a brief lengthening NO. 1559, VOL. 60] o1 the past. May I this evening venture to give rein to the impulses of advancing years? May I, at this last meeting of the Association in the eighteen hundreds, dare to dwell for a while upon the past, and to call to mind a few of the changes which have taken place in the world since those autumn days in which men were saying to each other that the last of the seventeen hundreds was drawing towards its end ? Dover in the year of our Lord seventeen hundred and ninety- nine was in many ways unlike the Dover of to-day. On moonless nights men groped their way in its narrow streets by the help of swinging lanterns and smoky torches, for no lamps lit the ways. By day the light of the sun struggled into the houses through narrow panes of blurred glass. Though the town then, as now, was one of the chief portals to and from the countries beyond the seas, the means of travel were scanty and dear, available for the most part to the rich alone, and, for all, beset with discomfort and risk. Slow and uncertain was the carriage of goods, and the news of the world outside came to the town—though it from its position learnt more than most towns—tardily, fitfully, and often falsely, The people of Dover sat then much in dimness, if not in darkness, and lived in large measure on themselves. They who study the pheno- mena of living beings tell us that light is the great stimulus of life and that the fulness of the life of a being or of any of its members may be measured by the variety, the swiftness, and the certainty of the means by which it is in touch with its surroundings. Judged from this standpoint then life at Dover, as indeed elsewhere, must have fallen far short of the life of to-day. The same study of living beings, however, teaches us that while from one point of view the environment seems to mould the organism, from another point the organism seems to be master of its environment. Going behind the change of cir- cumstances, we may raise the question, the old question, Was life in its essence worth more then than now? Has there been a real advance ? Let me at once relieve your minds by saying that I propose to leave this question in the main unanswered. It may be, or it may not be, that man’s grasp of the beautiful and of the good, if not looser, is not firmer than it was a hundred years ago. It may be, or it may not be, that man is no nearer to absolute truth, to seeing things as they really are, than he was then. I will merely ask you to consider with me for a few minutes how far, and in what ways, man’s laying hold of that aspect of or part of truth which we call natural knowledge, or sometimes science, differed in 1799 from what it is to-day, and whether that change must not be accounted a real advance, a real improvement in man. I do not propose to weary you by what in my hands would be the rash effort of attempting a survey of all the scientific results of the nineteenth century. It will be enough if for a little while I dwell on some few of the salient features distinguishing the way in which we nowadays look upon, and during the coming week shall speak of, the works of nature around us— though those works themselves, save for the slight shifting in- volved in a secular change, remain exactly the same—from the way in which they were looked upon and might have been spoken of at a gathering of philosophers at Dover in 1799. And I ask your leave to do so. In the philosophy of the ancients, earth, fire, air, and water were called ‘‘the elements.” It was thought, and rightly thought, that a knowledge of them and of their attributes was a necessary basis of a knowledge of the ways of nature. Trans- lated into modern language, a knowledge of these ‘‘ elements” of old means a knowledge of the composition of the atmosphere, of water, and of all the other things which we call matter, as well as a knowledge of the general properties of gases, liquids, and solids, and of the nature and effects of combustion. Of all these things our knowledge to-day is large and exact, and, though ever enlarging, in some respects complete. When did that knowledge begin to become exact ? To-day the children in our schools know that the air which wraps round the globe is not a single thing, but is made up of two things, oxygen and nitrogen,’ mingled together. They know, again, that water is not a single thing, but the product of two things, oxygen and hydrogen, joined together. They know that when the air makes the fire burn and gives the animal life, it is the oxygen in it which does the work. They know that all 4 Some may already know that there is at least a third thing, argon. ( . SEPTEMBE,& 14, 1899 | round them things are undergoing that union with oxygen which we call oxidation, and that oxidation is the ordinary source of heat and light. Let me ask you to picture to yourselves what confusion there would be to-morrow, not only in the discussions at the sectional meetings of our Association, but in the world at large, if it should happen that in the coming night some destroying touch should wither up certain tender structures in all our brains, and wipe out from our memories all traces of the ideas which cluster in our minds around the verbal tokens, oxygen and oxidation. How could any of us, not the so-called man of science alone, but even the man of business and the man of pleasure, go about his ways lacking those ideas? Yet those ideas were in 1799 lacking to all but a few. Although in the third quarter of the seventeenth century the light of truth about oxidation and combustion had flashed out in the writings of John Mayow, it came as a flash only, and died away as soon asithad come. For the rest of that century, and for the greater part of the next, philosophers stumbled about in darkness, misled for the most of the time by the phantom con- ception which they called phlogiston. It was not until the end of the third quarter of the eighteenth century that the new light, which has burned steadily ever since, lit up the minds of the men of science. The light came at nearly the same time from England and from France. Rounding off the sharp corners of controversy, and joining, as we may fitly do to-day, the two countries as twin bearers of a common crown, we may say that we owe the truth to Priestley, to Lavoisier, and Cavendish. If it was Priestley who was the first to demonstrate the existence of what we now call oxygen, it is to Lavoisier we owe the true conception of the nature of oxidation and the clear exposition of the full meaning of Priestley’s discovery, while the knowledge of the composition of water, the necessary complement of the knowledge of oxygen, came to us through Cavendish and, we may perhaps add, through Watt. The date of Priestley’s discovery of oxygen is 1774, Lavoisier’s classic memoir ‘‘ on the nature of the principle which enters into combination with metals during calcination ” appeared in 1775, and Cavendish’s paper on the composition of water did not see the light until 1784. During the last quarter of the eighteenth century this new idea of oxygen and oxidation was struggling into existence. How new was the idea is illustrated by the fact that Lavoisier himself at first spoke of that which he was afterwards, namely in 1778, led to call oxygen, the name by which it has since been known, as ‘‘the principle which enters into combination.” What difficulties its acceptance met with is illustrated by the fact that Priestley himself refused to the end of his life to grasp the true bearings of the discovery which he had made. In the year 1799 the knowledge of oxygen, of the nature of water and of air, and indeed the true conception of chemical composition and chemical change, was hardly more than beginning to be, and the century had to pass wholly away before the next great chemical idea, which we know by the name of the Atomic Theory of John Dalton, was made known. We have only to read the scientific literature of the time to recognise that a truth which is now not only woven as a master-thread into all our scientific conceptions, but even enters largely into the everyday talk and thoughts of educated people, was a hundred years ago struggling into existence among the philosophers themselves. It was all but absolutely unknown to the large world outside those select few. If there be one word of science which is writ large on the life of the present time, it is the word ‘‘electricity’’; it is, I take it, writ larger than any other word. The knowledge which it de- notes has carried its practical results far and wide into our daily life, while the theoretical conceptions which it signifies pierce deep into the nature of things. We are to-day proud, and justly proud, both of the material triumphs and of the intel- lectual gains which it has brought us, and we are full of even larger hopes of it in the future. At what time did this bright child of the nineteenth century have its birth ? He who listened to the small group of philosophers of Dover, who in 1799 might have discoursed of natural knowledge, would perhaps have heard much of electric machines, of electric sparks, of the electric fluid, and even of positive and negative electricity ; for frictional electricity had long been known and even carefully studied. Probably one or more of the group, dwelling on the observations which Galvani, an Italian, had NO. 1559, VOL. 60] NATURE 405 made known some twenty years before, developed views on the connection of electricity with the phenomena of living bodies. Possibly one of them was exciting the rest by telling how he had just heard that a professor at Pavia, one Volta, had discovered that electricity could be produced not only by rubbing together particular bodies, but by the simple contact of two metals, and had thereby explained Galvani’s remarkable results. For, indeed, as we shall hear from Prof. Fleming, it was in that very year, 1799, that electricity as we now know it took its birth. It was then that Volta brought to light the apparently simple truths out of which so much has sprung. The world, it is true, had to wait for yet some twenty years before both the practical and the theoretic worth of Volta’s discovery became truly pregnant, under the fertilising influence of another dis- covery. The loadstone and magnetic virtues had, like the electrifying power of rubbed amber, long been an old story. But, save for the compass, not much had come from it. And even Volta’s discovery might have long remained relatively barren had it been left to itself. When, however, in 1819, Oersted made known his remarkable observations on the relations of electricity to magnetism, he made the contact needed for the flow of a new current of ideas. And it is perhaps not too much to say that those ideas, developing during the years of the rest of the century with an ever-accelerating swiftness, have wholly changed man’s material relations to the circumstances of life, and at the same time carried him far in his knowledge of the nature of things. Of all the various branches of science, none perhaps is to-day, none for these many years past has been, so well known to, even if not understanded by, most people as that of geology. Its practical lessons have brought wealth to many ; its fairy tales have brought delight to more; and round it hovers the charm of danger, for the conclusions to which it leads touch on the nature of man’s beginning. In 1799 the science of geology, as we know it, was struggling into birth. There had been from of old cosmogonies, theories as to how the world had taken shape out of primzeval chaos. In that fresh spirit which marked the zealous search after natural knowledge pursued in the middle and latter part of the seven- teenth century, the brilliant Stenson, in Italy, and Hooke, in our own country, had laid hold of some of the problems pre- sented by fossil remains; and Woodward, with others, had laboured in the same field. In the eighteenth century, especi- ally in its latter half, men’s minds were busy about the physical agencies determining or modifying the features of the earth’s crust ; water and fire, subsidence from a primzeval ocean and transformation by outbursts of the central heat, Neptune and Pluto, were being appealed to, by Werner on the one hand, and by Desmarest on the other, in explanation of the earth’s phe- nomena. The way was being prepared, theories and views were abundant, and many sound observations had been made; and yet the science of geology, properly so called, the exact and proved knowledge of the successive phases of the world’s life, may be said to date from the closing years of the eighteenth century. In 1873 James Hutton put forward in a brief memoir his ‘*Theory of the Earth,” which in 1795, two years before his death, he expanded into a book ; but his ideas failed to lay hold of men’s minds until the century had passed away, when in 1802 they found an able expositor in John Playfair. The very same year that Hutton published his theory, Cuvier came to Paris and almost forthwith began, with Brongniart, his immortal researches into the fossils of Paris and its neighbourhood. And four years later, in the year 1799 itself, William Smith’s tabular list of strata and fossils saw the light. It is, I believe, not too much to-say that out of these geology, as we now know it, sprang. It was thus in the closing years of the eighteenth century that was begun the work which the nineteenth century has carried forward to such great results. But at that time only the select few had grasped the truth, and even they only the beginning of it. Outside a narrow circle the thoughts, even of the educated, about the history of the globe were bounded by the story of the Deluge—though the story was often told in a strange fashion—or were guided by fantastic views of the plastic forces of a sportive nature. In another branch of science, in that which deals with the problems presented by living beings, the thoughts of men in 1799 were also very difterent from the thoughts of men to-day. 466 NATURE [SEPTEMBE!Y 14, 1899 It is a very old quest, the quest after the knowledge of the nature of living beings, one of the earliest on which man set out ; for it promised to lead him to a knowledge of himself, a promise which perhaps is still before us, but the fulfilment of which is as yet far off. As time has gone on, the pursuit of natural knowledge has seemed to Jerd man away from himself into the furthermost parts of the universe, anu into secret workings of nature in which he appears to be of little or no account ; and his knowledge of the nature of living things. and so of his own nature, has advanced slowly, waiting till the progress of other branches of natural knowledge can bring it aid. Vet in the past hundred years, the biologic sciences, as we now call them, have marched rapidly onward. We may look upon a living body as a machine doing work in accordance with certain laws, and may seek to trace out the working of the inner wheels, how these raise up the lifeless dust into living matter, and let the living matter fall away again into dust, giving ont movement and heat. Or we may look upon the individual life as a link in a long chain, joining something which went before to something about to come, a chain whose beginning lies hid in the farthest past, and may seek to know the ties which bind one life to another. As we call up to view the long series of living forms, living now or flitting like shadows on the screen of the past, we may strive to lay hold of the in- fluences which fashion the garment of life. Whether the prob- lems of life are looked upon from the one point of view or the other, we to-day, not biologists only, but all of us, have gained a knowledge hidden even from the philosophers a hundred years ago. Of the problems presented by the living body viewed as a machine, some may be spoken of as mechanical, others as physical, and yet others as chemical. while some are, apparently at least, none of these. In the seventeenth century William Harvey, laying hold of the central mechanism of the blood stream, opened up a path of inquiry which his own age and the century which followed trod with marked success. The know- ledge of the mechanics of the animal and of the plant advanced apace ; but the physical and chemical problems had yet to wait. The eighteenth century, it is true, had its physics and its chemistry ; but, in relation at least to the problems of the living being, a chemistry which knew not oxygen and a physics which knew not the electricity of chemical action were of little avail. The philosopher of 1799, when he discussed the functions of the animal or of the plant involving chemical changes, was fain for the most part, as were his predecessors in the century before, to have recourse to such vague terms as ‘‘ fermentation” and the like ; to-day our treatises on physiology are largely made up of precise and exact expositions of the play of physical agencies and chemical bodies in the living organism. He made use of the words ‘‘ vital force” or ‘* vital principle,’’ not as an occasional, but as a common explanation of the phenomena of the living body. During the present century, especially during its latter half, the idea embodied in those words has been driven away from one seat after another; if we use it now when we are dealing with the chemical and physical events of life we use it with reluctance, as a deus ex machina to be appealed to only when everything else has failed. Some of the problems—and those, perhaps, the chief prob- lems—of the living body have to be solved neither by physical nor by chemical methods, but by methods of their own. Such are the problems of the nervous system. In respect to these the men of 1799 were on the threshold of a pregnant discovery. During the latter part of the present century, and especially during its last quarter, the analysis of the mysterious pro- cesses in the nervous system which issue as feeling, thought, and power to move, has been pushed forward with a success conspicuous in its practical, and full of promise in its theoretical, gains. That analysis may be briefly de- scribed as a following up of threads. We now know that what takes place along a tiny thread which we call a nerve-fibre differs from that which takes place along its fellow-threads, that differing nervous impulses travel along different nerve-fibres, and that nervous and psychical events are the outcome of the clash- ing of nervous impulses as they sweep along the closely-woven web of living threads of which the brain is made. We have learnt by experiment and by observation that the pattern of the web determines the play of the impulses, and we can already explain many of the obscure problems, not only of nervous disease, but of nervous life, by an analysis which is a tracking out the devious and linked paths of nervous threads. The NO. 1559, VOL. 60] very beginning of this analysis was known in 1799. Men knew that nerves were the agents of feeling and of the movements of muscles; they had learnt much about what this part or that part of the brain could do; but they did not know that one nerve-fibre differed from another in the very essence of its work. It was just about the end of the past century, or the beginning of the present one, that an English surgeon began to ponder over a conception which, however, he did not make known until some years later, and which did not gain complete demonstration and full acceptance until still more years had passed away. It was in 1811, in a tiny pamphlet published privately, that Charles Bell put forward his ‘‘ New Idea” that the nervous system was constructed on the principle that ‘* the nerves are not single nerves possessing various powers, but bundles of different nerves, whose filaments are united for the convenience of distribution, but which are distinct in office as they are in origin from the brain.” Our present knowledge of the nervous system is to a large extent only an exemplification and expansion of Charles Bell’s “* New Idea,” and has its origin in that. If we pass from the problems of the living organism viewed asa machine to those presented by the varied features of the different creatures who have lived or w'o still live on the earth, we at once call to mind that the middle years of the present century mark an epoch in biologic thought such as never came before, for it was then that Charles Darwin gave to the world the ‘ Origin of Species.” That work, however, with all the far-reaching effects which it has had, could have had little or no effect, or, rather, could not have come into existence, had not the earlier half of the century been in travail preparing for its coming. For the germinal idea of Darwin appeals, as to witnesses, to the results of two lines of biologic investigation which were almost unknown to the men of the eighteenth century. To one of these lines I have already referred. Darwin, as we know, appealed to the geological record: and we also know how that record, imperfect as it was then, and imperfect as it must always remain, has since his time yielded the most striking proofs of at least one part of his general conception. In 1799 there was, as we have seen, no geological record at all. Of the other line I must say a few words. To-day the merest beginner in biologic study, or even that exemplar of acquaintance without knowledge, the general reader, is aware that every living being, even man himself, begins its independent existence as a tiny ball, of which we can, even acknowledging to the full the limits of the optical analysis at our command, assert with confidence that in structure, using that word in its ordinary sense, it is in all cases absolutely simple. It is equally well known that the features of form which supply the characters of a grown-up living being, all the many and varied features of even the most complex organism, are reached as the goal of a road, at times a long road, of successive changes ; that the life of every being, from the ovum to its full estate, is a series of shifting scenes, which come and go, some- times changing abruptly, sometimes melting the one into the other, like dissolving views, all so ordained that often the final shape with which the creature seems to begin, or is said to begin, its life in the world is the outcome of many shapes, clothed with which it has in turn lived many lives before its seeming birth. Allor nearly all the exact knowledge of the laboured way in which each living creature puts on its proper shape and struc- ture is the heritage of the present century. Although the way in which the chick is moulded in the egg was not wholly un- known even to the ancients, and in later years had been told, first in the sixteenth century by Fabricius, then in the seven- teenth century in a more clear and striking manner by the great Italian naturalist Malpighi, the teaching thus offered had been neglected or misinterpreted. At the close of the eighteenth century the dominant view was that in the making of a creature out of the egg there was no putting on of wholly new parts, no epigenesis. It was taught that the entire creature lay hidden in the egg, hidden by reason of the very transparency of its sub- stance, lay ready-made but folded up, as it were, and that the process of development within the egg or within the womb was a mere unfolding, a simple evolution. Nor did men shrink from accepting the logical outcome of such a view—namely, that within the unborn creature itself lay in like manner, hidden and folded up, its offspring also, and within that again its offspring in turn, after the fashion of a cluster of — SEPTEMBER 14, 1899] NALURE 467 ivory balls carved by Chinese hands, one within the other. This was no fantastic view put forward by an imaginative dreamer ; it was seriously held by sober men, even by men like’ yi y the illustrious Haller, in spite of their recognising that as the chick grew in the egg some changes of form took place. Though so early as the middle of the eighteenth century Friedrich Caspar Wolff and, later on, others had strenuously opposed such a view, it held its own, not only to the close of the century, but far on into the next. It was not until a quarter of the present century had been added to the past that Von Baer made known the results of researches which once and for all swept away the old view. He and others working after him made it clear that each individual puts on its final form and structure, not by an unfolding of pre-existing hidden features, but by the formation of new parts through the continued differentiation of a primitively simple material. It was also made clear that the successive changes which the embryo undergoes in its progress from the ovum to maturity are the ex- pression of morphologic laws, that the progress is one from the general to the special, and that the shifting scenes of embryonic life are hints and tokens of lives lived by ancestors in times long past. If we wish to measure how far off in biologic thought the end of the last century stands, not only from the end but even from the middle of this one, we may imagine Darwin striving to write the ‘Origin of Species” in 1799. We may fancy him being told by philosophers that one group of living beings differed from another group because all its members and all their ancestors came into existence at one stroke when the firstborn progenitor of the race, within which all the rest were folded up, stood forth as the result of a creative act. . We may fancy him listening to a debate between the philosopher who maintained that all the fossils strewn in the earth were the remains of animals or plants churned up in the turmoil of a violent universal flood, and dropped in their places as the waters went away, and him who argued that such were not really the “spoils of living creatures,” but the products of some playful plastic power which out of the superabundance of its energy fashioned here and there the lifeless earth into forms which imitated, but only imitated, those of living things. Could he amid such surroundings by any flight of genius have beat his way to the conception for which his name will ever be known ? Here I may well turn away from the past. It isnot my purpose, nor, as I have said, am I fitted, nor is this perhaps the place, to tell even in outline the tale of the work of science in the nineteenth century. I am content to have pointed out that the two great sciences of chemistry and geology took their birth, or at least began to stand alone, at the close of the last century, and have grown to be what we know them now within about a hundred years, and that the study of living beings has within the same time been so transformed as to be to-day something wholly different from what it was in1799. And, indeed, to say more would be to repeat almost the same story about other things. If our present knowledge of electricity is essentially the child of the nineteenth century, so also is our present know- ledge of many other branches of physics. And those most ancient forms of exact knowledge, the knowledge of numbers and of the heavens, whose beginning is lost in the remote past, have, with all other kinds of natural knowledge, moved onward during the whole of the hundred years with a speed which is ever increasing. I have said, I trust, enough to justify the statement that in respect to natural knowledge a great gulf lies between 1799 and 1899. That gulf, moreover, is a twofold one: not only has natural knowledge been increased, but men have run to and fro spreading it as they go. Not only have the few driven far back round the full circle of natural knowledge the dark clouds of the unknown which wrap us all about, but also the many walk in the zone of light thus increasingly gained. If it be true that the few to-day are, in respect to natural know- ledge, far removed from the few of those days, it is also true that nearly all which the few alone knew then, and much which they did not know, has now become the common knowledge of the many. What, however, I may venture to insist upon here is that the difference in respect to natural knowledge, whatever be the case with other differences between then and now, is undoubtedly a difference which means progress. The span between the science of that time and the science of to-day is beyond all question a great stride onwards. NO. 1559, VOL. 60] We may say this, but we must say it without boasting. For the very story of the past which tells of the triumphs of science bids the man of science put away from him all thoughts of vain- glory. And that by many tokens. f Whoever, working at any scientific problem, has occasion to study the inquiries into the same problem made by some fellow- worker in the years long gone by, comes away from that study humbled by one or other of two different thoughts. On the one hand, he may find, when he has translated the language of the past into the phraseology of to-day, how near was his fore- runner of old to the conception which he thought, with pride, was all his own, not only so true but so new. On the other hand, if the ideas of the investigator of old, viewed in the light of modern knowledge, are found to be so wide of the mark as to seem absurd, the smile which begins to play upon the lips of the modern is checked by the thought, Will the ideas which I am now putting forth, and which I think explain so clearly, so fully, the problem in hand, seem to some worker in the far future as wrong and as fantastic as do these of my forerunner to me? In either case his personal pride is checked. Further, there is written clearly on each page of the history of science, in characters which cannot be overlooked, the lesson that no scientific truth is born anew, coming by itself and of itself. Each new truth is always the offspring of something which has gone before, becoming in turn the parent of something coming after. In this aspect the man of science is unlike, or seems to be unlike, the poet and the artist. The poet is born, not made ; he rises up, no man knowing his beginnings; when he goes away, though men after him may sing his songs for centuries, he himself goes away wholly, having taken with him his mantle, for this he can give to none other. The man of science is not thus creative ; he is created. His work, however great it be, is not wholly his own; it is in part the outcome of the work of men who have gone before. Again and again a conception which has made a name great has come, not so much by the man’s own effort as out of the fulness of time. Again and again we may read in the words of some man of old the outlines of an idea which in later days has shone forth as a great acknowledged truth. From the mouth of the man of old the idea dropped barren, fruitless ; the world was not ready for it, and heeded it not ; the concomitants and abutting truths which could give it power to work were wanting. Coming back again in later days, the same idea found the world awaiting it ; things were in travail preparing for it ; and some one, seizing the right moment to put it forth again, leapt into fame. It is not so much the men of science who make science, as some spirit which, born of the truths already won, drives the man of science onward, and uses him to win new truths in turn. It is because each man of science is not his own master, but one of many obedient servants of an impulse which was at work long before him, and will work long after him, that in science there is no falling back. In respect to other things there may be times of darkness and times of light, there may be risings, de- cadences, and revivals. In science there is only progress. The path may not be always a straight line, there may be swerving to this side and to that, ideas may seem to return again and again to the same point of the intellectual compass ; but it will always be found that they have reached a higher level—they have moved, not in a circle, but in a spiral. Moreover, science 1s not fashioned as is a house, by putting brick to brick, that which is once put remaining as it was put to the end. The growth of science is that of a living being. As in the embryo phase follows phase, and each member of the body puts on in suc- cession different appearances, though all the while the same member, so a scientific conception of one age seems to differ from that of a following age, though it is the same one in the pro- cess of being made; and as the dim outlines of the early embryo, as the being grows, become more distinct and sharp, like a pic- ture on ascreen brought more and more into focus, so the dim gropings and searchings of the men of science of old are by repeated approximations wrought into the clear and exact con- clusions of later times. The story of natural knowledge, af science, in the nineteenth century, as, indeed, in preceding centuries, is, I repeat, a story of continued progress. There is in it not so much as a hint of falling back, not even of standing still. What is gained by scientific inquiry is gained for ever; it may be added to, it may seem to be covered up, but it can never be taken away. Confident that the progress will go on, we cannot help peering 468 WALOURE [SEPTEMBER 14, 1899 into the years to come and straining our eyes to foresee what science will become and what it will do as they roll on. While we do so, the thought must come to us, Will all the increasing knowledge of nature avail only to change the ways of man— will it have no effect on man himself ? The material good which mankind has gained and is gaining through the advance of science is so imposing as to be obvious to every one, and the praises of this aspect of science are to be found in the mouths of all. Beyond all doubt science has greatly lessened and has markedly narrowed hardship and suffering ; beyond all doubt science has largely increased and has widely diffused ease and comfort. The appliances of science have, as it were, covered with a soft cushion the rough places of life, and that not for the rich only, but also for the poor. So abundant and so prominent are the material benefits of science that in the eyes of many these seem to be the only benefits which she brings. She is often spoken of as if she were useful and nothing more, as if her work were only to administer to the material wants of man. Is this so ? We may begin to doubt it when we reflect that the triumphs of science which bring these material advantages are in their very nature intellectual triumphs. The increasing benefits brought by science are the results of man’s increasing mastery over nature, and that mastery is increasingly a mastery of mind ; it is an increasing power to use the forces of what we call inanimate nature in place of the force of his own or other creatures’ bodies ; it is an increasing use of mind in place of muscle. Is it to be thought that that which has brought the mind so greatly into play has had no effect on the mind itself? Is that part of the mind which works out scientific truths a mere slavish machine producing results it knows not how, having no part in the good which in its working it brings forth ? What are the qualities, the features of that scientific mind which has wrought, and is working, such great changes in man’s relation tonature? In seeking an answer to this question we have not to inquire into the attributes of genius. Though much of the progress of science seems to take on the form of a series of great steps, each made by some great man, the distinction in science between the great discoverer and the humble worker is one of degree only, not of kind. As I was urging just now, the greatness of many great names in science is often, in large part, the greatness of occasion, not of absolute power. The qualities which guide one man to a small truth silently taking its place among its fellows, as these go to make up progress, are at bottom the same as those by which another man is led to something of which the whole world rings. The features of the fruitful scientific mind are in the main three. In the first place, above all other things, his nature must be one which vibrates in unison with that of which he is in search ; the seeker after truth must himself be truthful, truthful with the truthfulness of nature. For the truthfulness of nature is not wholly the same as that which man sometimes calls truthful- ness. It is far more imperious, far more exacting. Man, un- scientific man, is often content with ‘‘the nearly” and ‘‘the almost.” Nature never is. It is not her way to call the same two things which differ, though the difference may be measured by less than the thousandth of a milligramme or of a»millimetre, or by any other like standard of minuteness. And the man who, carrying the ways of the world into the domain of science, thinks that he may treat nature’s differences in any other way than she treats them herself, will find that she resents his conduct; if he in carelessness or in disdain overlooks the minute difference which she holds out to him as a signal to guide him in his search, the projecting tip, as it were, of some buried treasure, he is bound to go astray, and the more strenu- ously he struggles on, the farther will he find himself from his true goal. In the second place, he must be alert of mind. Nature is ever making signs to us, she is ever whispering to us the beginnings of her secrets; the scientific man must be ever on the watch, ready at once to lay hold of nature’s hint however small, to listen to her whisper however low. In the third place, scientific inquiry, though it be pre- eminently an intellectual effort, has need of the moral quality of courage—not so much the courage which helps a man to face a sudden difficulty as the courage of steadfast endurance. NO. 1559, VOL. 60] 4 Almost every inquiry, certainly every prolonged inquiry, sooner or later goes wrong. The path, at first so straight and clear, grows crooked and gets blocked; the hope and enthusiasm, or even the jaunty ease, with which the inquirer set out leave him, and he falls into a slough of despond. That is the critical moment calling for courage. Struggling through the slough he will find on the other side the wicket- gate opening up the real path; losing heart he will turn back and add one more stone to the great cairn of the unaccom- plished. But, I hear some one say, these qualities are not the peculiar attributes of the man of science ; they may be recognised as belonging to almost every one who has commanded or deserved success, whatever*may have been his walk of life. ‘That isso. That is exactly what I would desire to insist, that the men of science have no peculiar virtues, no special powers. They are ordinary men, their characters are common, even commonplace. Science, as Huxley said, is organised common sense, and men of science are common men, drilled in the ways of common sense. For their life has this feature. ° Though in themselves they are no stronger, no better than other men, they possess a strength which, as I just now urged, is not their own, but is that of the science whose servants they are. Even in his apprenticeship, the scientific inquirer, while learning what has been done before his time, if he learns it aright, so learns it that what is known may serve him, not only as a vantage ground whence to push off into the unknown, but also as a compass to guide him in his course. And when fitted for his work he enters on inquiry itself, what a zealous anxious guide, what astrict and, because strict, helpful schoolmistress does nature make herself to him ! Under her care every inquiry, whether it bring the inquirer to a happy issue or seem to end in nought, trains him for the next effort. She so orders her ways that each act of obedience to her makes the next act easier for him, and step by step she leads him on towards that perfect obedience which is complete mastery. Indeed, when we reflect on the potency of the discipline of scientific inquiry we cease to wonder at the progress of scientific knowledge. The results actually gained seem to fall so far short of what under such guidance might have been expected to have been gathered in that we are fain to conclude that science has called to follow her, for the most part, the poor in intellect and the wayward in spirit. Had she called to her service the many acute minds who have wasted their strength struggling in vain to solve hopeless problems, or who have turned their energies to things other than the increase of knowledge ; had she called to her service the many just men who have walked straight without the need ofa rod to guide them, how much greater than it has been would have been the progress of science, and how many false teachings would the world have been spared! To men of science themselves, when they con- sider their favoured lot, the achievements of the past should serve, not as a boast, but asa reproach. If there be any truth in what I have been urging, that the pursuit of scientific inquiry is itself a training of special potency, giving strength to the feeble and keeping in the path those who are inclined to stray, it is obvious that the material gains of science, great as they may be, do not make up all the good which science brings or may bring to man. We especially, perhaps, in these later days, through the rapid development of the physical sciences, are too apt to dwell on the material gains alone. As a child in its infancy looks upon its mother only as a giver of good things, and does not learn till in after days how she was also showing her love by carefully training it in the way it should go, so we, too, have thought too much of the gifts of science, overlooking her power to guide. Man does not live by bread alone, and science brings him more than bread. It is a great thing to make two blades of grass grow where before one alone grew ; but it is no less great a thing to help a man to come to a just conclusion on the questions with which he has to deal. We may claim for science that while she is doing the one she may be so used as todo the otheralso. The dictum just quoted, that science is organised common sense, may be read as meaning that the common problems of life which common people have to solve are to be solved by the same methods by which the man of science solves his special problems. It follows that the training which does so much for him may be looked to as promising to do much for them. Such aid can come from science on two conditions SEPTEMBER 14, 1899] NATURE 469 only. In the first place, this her influence must be acknow- ledged ; she must be duly recognised as a teacher no less than as a hewer of wood and a drawer of water. And the pursuit of science must be followed, not by the professional few only, but, at least in such measure as will ensure the influence of example, by the many. But this latter point I need not urge before this great Association, whose chief object during more than half a century has been to bring within the fold of science all who would answer to the call. In the second place, it must be understood that the training to be looked for from science is the outcome, not of the accumulation of scientific knowledge, but of the practice of scientific inquiry. Man may have at his fingers’ ends all the accomplished results and all the current opinions of any one or of all the branches of science, and yet remain wholly unscientific in mind ; but no one can have carried out even the humblest research without the spirit of science in some measure resting upon him. And that spirit may in part be caught even without entering upon an actual investigation in search of a new truth. The learner may be led to old truths, even the oldest, in more ways than one. He may be brought abruptly to a truth in its finished form, coming straight to it like a thief climbing over the wall ; and the hurry and press of modern life tempt many to adopt this quicker way. Or he may be more slowly guided along the path by which the truth was reached by him who first laid hold of it. It is by this latter way of learning the truth, and by this alone, that the learner may hope to catch something at least of the spirit of the scien- tific inquirer. This is not the place, nor have I the wish, to plunge into the turmoil of controversy; but, if there be any truth in what I have been urging, then they are wrong who think that in the schooling of the young science can be used with profit only to train those for whom science will be the means of earning their bread. It may be that from the point of view of the pedagogic art the experience of generations has fashioned out of the older studies of literature an instrument of discipline of unusual power, and that the teaching of science is as yet but a rough tool in unpractised hands. That, however, is not an adequate reason why scope should not be given for science to show the value which we claim for it as an intellectual training fitted for all sorts and conditions of men. Nor need the studies of humanity and literature fear her presence in the schools, for if her friends maintain‘ that that teaching is one-sided, and there- fore misleading, which deals with the doings of man only, and is silent about the works of nature, in the sight of which he and his doings shrink almost to nothing, she herself would be the first to admit that that teaching is equally wrong which deals only with the works of nature and says nothing about the doings of man, who is, to us at least, nature’s centre. There is yet another general aspect of science on which I would crave leave to say a word. In that broad field of human life which we call politics, in the struggle, not of man with man, but of race with race, science works for good. If we look only on the surface it may at first sight seem otherwise. In no branch of science has there during these later years been greater activity and more rapid progress than in that which furnishes the means by which man brings death, suffering, and disaster on his fellow-men. If the healer can look with pride on the increased power which science has given him to alleviate human suffering and ward off the miseries of disease, the destroyer can look with still greater pride on the power which science has given him to sweep away lives and to work desolation and ruin ; while the one has slowly been learning to save units, the other has quickly learnt to slay thousands. But, happily, the very greatness of the modern power of destruction is already be- coming a bar to its use, and bids fair—may we hope before long 2—wholly to put an end to it; in the words of Tacitus, though in another sense, the very preparations for war, through the character which science gives them, make for peace. = Moreover, not in one branch of science only, but in all, there is a deep undercurrent of influence sapping the very foundations of all war, As I have already urged, no feature of scientific inquiry is more marked than the dependence of each step for- ward on other steps which have been made before. The man of science cannot sit by himself in his own cave weaving out results by his own efforts, unaided by others, heedless of what others have done and are doing. He is but a bit of a great system, a joint ina great machine, and he can only work aright when he is in due touch with his fellow-workers, If his NO. 1559, VOL. 60] labour is to be what it ought to be, and is to have the weight which it ought to have, he must know what is being done, not by himself, but by others, and by others not of his own land and speaking his tongue only, but also of other lands and of other speech. Hence it comes about that to the man of science the barriers of manners and of speech which pen men into nations become more and more unreal and indistinct. He recognises his fellow-worker, wherever he may live and whatever tongue he may speak, as one who is pushing forward shoulder to shoulder with him towards a common goal, as one whom he is helping and who is helping him. The touch of science makes the whole world kin. The history of the past gives us many examples of this brotherhood of science. In the revival of learning throughout the sixteenth and seventeenth centuries, and some way on into: the eighteenth century, the common use of the Latin tongue made intercourse easy. In some respects, in those earlier days. science was more cosmopolitan than it afterwards became. In spite of the difficulties and hardships of travel, the men of science of different lands again and again met each other face to face, heard with their ears, and saw with their eyes what their brethren had to say or to show. The Englishman took the long journey to Italy to study there ; the Italian, the French- man, and the German wandered from one seat of learning to another ; and many a man held a chair in acountry not his own. There was help, too, as well as intercourse. The Royal Society of London took upon itself the task of publishing nearly all the works of the great Italian Malpighi, and the brilliant Lavoisier, two years before his own countrymen in their blind fury slew him, received from the same body the highest token which it could give of its esteem. In these closing years of the nineteenth century this great need of mutual knowledge and of common action felt by men of science of different lands is being manifested in a special way, Though nowadays what is done anywhere is soon known every- where, the news of a discovery being often flashed over the globe by telegraph, there is an increasing activity in the direc- tion of organisation to promote international meetings and inter- national co-operation. In almost every science inquirers from many lands now gather together at stated intervals in inter- national congresses to discuss matters which they have in common at heart, and go away each one feeling strengthened by having met his brother. The desire that in the struggle to lay bare the secrets of Nature the least waste of human energy should be incurred is leading more and more to the concerted action of nations combining to attack problems the solution of which is difficult and costly. The determination of standards of measurement, magnetic surveys, the solution of great geodetic problems, the mapping of the heavens and of the earth—all these are being carried on by international organisations. In this and in other countries men’s minds have this long while past been greatly moved by the desire to make fresh efforts to pierce the dark secrets of the forbidding Antarctic regions. Belgium has just made a brave single-handed attempt ; a private enterprise sailing from these shores is struggling there now, lost for the present to our view; and this year we in England and our brethren in Germany are, thanks to the pro- mised aid of the respective Governments, and no less to private liberality, in which this Association takes its share, able to begin the preparation of carefully organised expeditions. That in- ternational amity of which I am speaking is illustrated by the fact that in this country and in that there is not only a great desire, but a firm purpose, to secure the fullest co-operation, between the expeditions which will leave the two shores. If in this momentous attempt any rivalry be shown between the two nations, it will be for each a rivalry, not in forestalling, but in assisting the other. May I add that if the story of the past may seem to give our nation some claim to the seas as more peculiarly our own, that claim bespeaks a duty likewise peculiarly our own to leave no effort untried by which we may plumb the seas’ yet unknown depths and trace their yet unknown shores? That claim, if it means anything, means that when nations are joining hands in the dangerous work of exploring the unknown South, the larger burden of the task should fali to Britain’s share ; it means that we in this country should see to it, and see to it at once, that the concerted Antarctic expedi- tion, which in some two years or so will leave the shores of Germany, of England, and, perhaps, of other lands, should, so far as we are concerned, be so equipped and so sustained that the risk of failure and disaster may be made as. small, and the 470 NABORE [SEPTEMBER 14, 1899 hope of being able, not merely to snatch a hurried glimpse of lands not yet seen, but to gather in with full hands a rich harvest of the facts which men not of one science only, but of many, long to know, as great as possible. Another international scientific effort demands a word of notice. The need which every inquirer in science feels to know, and to know quickly, what his fellow-worker, wherever on the globe he may be carrying on his work or making known his re- sults, has done or is doing, led some four years back to a pro- posal for carrying out by international co-operation a complete current index, issued promptly, of the scientific literature of the world. Though much labour in many lands has been spent upon the undertaking, the project is not yet an accomplished fact. Nor can this, perhaps, be wondered at, when the diffi- culties of the task are weighed. Difficulties of language, difficulties of driving in one team all the several sciences, which, like young horses, wish each to have its head free with leave to go its own way, difficulties mechanical and financial of press and post, difficulties raised by existing interests—these and yet other difficulties are obstacles not easy to be overcome. The most striking and the most encouraging features of the deliberations which have now been going on for three years have been the repeated expressions, coming not from this or that quarter only, but from almost all quarters, of an earnest desire that the effort should succeed, of a sincere belief in the good of international co- operation, and of a willingness to sink as far as possible individual interests for the sake of the common cause. In the face of such a spirit we may surely hope that the many diffi- culties will ultimately pass out of sight. Perhaps, however, not the least notable fact of international ¢o-operation in science is the proposal which has been made within the last two years that the leading academies of the world should, by representatives, meet at intervals to discuss questions in which the learned of all lands are interested. A month hence a preliminary meeting of this kind will be held at Wiesbaden ; and it is at least probable that the closing year of that nineteenth century in which science has played so great a part may at Paris during the great World’s Fair—which every friend, not of science only, but of humanity, trusts may not be put aside or even injured through any untoward event, and which promises to be an occasion, not of pleasurable sight-seeing only, but also, by its many international congresses, of inter- national communing in the search for truth—witness the first select Witenagemote of the science of the world. I make no apology for having thus touched on international co-operation. I should have been wanting, had I not done so, to the memorable occasion of this meeting. A hundred years ago two great nations were grappling with each other in a fierce struggle, which had lasted, with pauses, for many years, and was to last for many years to come; war was on every lip and in almost every heart. To-day this meeting has, by a common wish, been so arranged that those two nations should, in the persons of their men of science draw as near together as they can, with nothing but the narrow streak of the Channel be- tween them, in order that they may take counsel together on matters in which they have one interest and a common hope. May we not look upon this brotherly meeting as one of many signs that science, though she works in a silent manner and in ways unseen by many, is steadily making for peace ? Looking back, then, in this last year of the eighteen hundreds, on the century which is drawing to its close, while we may see in the history of scientific inquiry much which, telling the man of science of his shortcomings and his weakness, bids him be humble, we see also much, perhaps more, which gives him hope. Hope is indeed one of the watchwords of science, In the latter-day writings of some who know not science, much may be read which shows that the writer is losing or has lost hope in the future of mankind. There are not a few of these ; their repeated utterances make a sign of the times. Seeing in matters lying outside science few marks of progress and many tokens of decline or of decay, recognising in science its material benefits only, such men have thoughts of despair when they look forward to the times to come. But if there be any truth in what I have attempted to urge to-night, if the intellectual, if the moral influences of science are no less marked than her material benefits, if, moreover, that which she has done is but the earnest of that which she shall do, such men may pluck up courage and gather strength by laying hold of her garment. We men of science at least need NO. 1559, VOL. 60] not share their views or their fears. Our feet are set, not on the shifting sands of the opinions and of the fancies of the day, but on a solid foundation of verified truth, which by the labours of each succeeding age is made broader and more firm. To us the past is a thing to look back upon, not with regret, not as something which has been lost, never to be regained, but with content, as something whose influence is with us still, helping us on our further way. With us, indeed, the past points not to itself, but to the future; the golden age is in front of us, not behind us ; that which we do know is a lamp whose brightest beams are shed into the unknown before us, showing us how much there is ahead and lighting up the way to reach it. We are confident in the advance because, as each one of us feels that any step forward which he may make is not ordered by himself alone and is not the result of his own sole efforts in the present, but is, and that in large measure, the outcome of the labours of others in the past, so each one of us has the sure and certain hope that as the past has helped him, so his efforts, be they great or be they small, will be a help to those to come. SECTION A. MATHEMATICS AND PHYSICS. OPENING ADDRESS BY PRor. J. H. PoynTinG, F.R.S., PRESIDENT OF THE SECTION. THE members of this Section will, I am sure, desire me to give expression to the gratification that we all feel in the real- isation of the scheme first proposed from this chair by Dr. Lodge, the scheme for the establishment of a National Physical Laboratory. It would be useless here to attempt to point out the importance of the step taker in the definite foundation of the Laboratory, for we all recognise that it was absolutely necessary for the due progress of physical research in this country. It is matter for congratulation that the initial guid- ance of the work of the Laboratory has been placed in such able hands. While the investigation of nature is ever increasing our know- ledge, and while each new discovery is a positive addition never again to be lost, the range of the investizition and the nature of the knowledge gained form the theme of endless discussion. And in this discussion, so different are the views of different schools of thought, that it might appear hopeless to look for general agreement, or to attempt to mark progress. Nevertheless, I believe that in some directions there has been real progress, and that physicists, at least, are tending towards a general agreement as to the nature of the laws in which they embody their discoveries, of the explanations which they seek to give, and of the hypotheses they make in their search for explanations. I propose to ask you to consider the terms of this agreement, and the form in which, as it appears to me, they should be drawn up. The range of the physicist’s study consists in the visible motions and other sensible changes of matter. The experiences with which he deals are the impressions on his senses, and his aim is to describe in the shortest possible way how his various senses have been, will be, or would be affected. His method consists in finding out all likenesses, in classing together all similar events, and so giving an account as concise as possible of the motions and changes observed. His success in the search for likenesses and his striving after conciseness of description lead him to imagine such a constitution of things that likenesses exist even where they elude his observation, and he is thus enabled to simplify his classification on the assump- tion that the constitution thus imagined is a reality. He is enabled to predict on the assumption that the likenesses of the future will be the likenesses of the past. His account of nature, then, is, as it is often termed, a descriptive account. Were there no similarities in events, our account of them could not rise above a mere directory, with each individual event entered up separately with its address. But the simi- larities observed enable us to class large numbers of events together, to give general descriptions, and indeed to make, instead of a directory, a readable book of science, with laws as the headings of the chapters. These laws are, I believe, in all cases brie: descriptions o observed similarities. By way of illustration let us take two or three examples. SEPTEMBER 14, 1899 | NATURE 47} The law of gravitation states that to each portion of matter we can assign a constant—its mass—such that there is an ac- celeration towards it of other matter proportional to that mass divided by the square of its distance away. Or all bodies re- semble each other in having this acceleration towards each other. Hooke’s law for the case of a stretched wire states that each successive equal small load produces an equal stretch, or states that the behaviour of the wire is similar for all equal small pulls. Joule’s law for the heat appearing when a current flows in a wire states that the rate of heat development is proportional to the square of the current multiplied by the resistance, or states that all the different cases resemble each other in having H +C?R¢ constant. And, generally, when a law is expressed by an equation, that equation is a statement that two different sets of measurements are made, represented by the terms on the two sides of the equation, and that all the different cases resemble each other in that the two sets have the constant relation expressed by the equation. Accurate prediction is based on the assumption that when we have made the measurements on the one side of the equation we can tell the result of the measurements implied on the other side. If this is a true account of the nature of physical laws, they have, we must confess, greatly fallen off in dignity. No long time ago they were quite commonly described as the Fixed Laws of Nature, and were supposed sufficient in themselves to govern the universe. Now we can only assign to them the humble rank of mere descriptions, often tentative, often erro- neous, of similarities which we believe we have observed. The old conception of laws as self-suffcing governors of nature was, no doubt, a survival of a much older conception of the scope of physical science, a mode of regarding physical phenomena which had itself passed away. I imagine that originally man looked on himself and the re- sult of his action in the motions and changes which he produced in matter, as the one type in terms of which he should seek to describe all motions and changes. Knowing that his purpose and will were followed by motions and changes in the matter about him, he thought of similar purpose and will behind all the motions and changes which he observed, however they oc- curred ; and he believed, too, that it was necessary to think thus in giving any consistent account of his observations. Taking this anthropomorphic—or, shall we say, psychical— view, the laws he formulated were not merely descriptions of similarities of behaviour, but they were also expressions of fixed purpose and the resulting constancy of action. They were commands given to matter which it must obey. The psychical method, the introduction of purpose and will, is still appropriate when we are concerned with living beings. Indeed, it is the only method which we attempt to follow when we are describing the motions of our fellow-creatures. No one seeks to describe the motions and actions of himself and of his fellow-men, and to classify them without any reference to the similarity of purpose when the actions are similar. But as the study of nature progressed, it was found to be quite futile to bring in the ideas of purpose and will when merely describing and classifying the motions and changes of non-living matter. Purpose and will could be entirely left out of sight, and yet the observed motions and changes could be described, and pre- dictions could be made as to future motions and changes. Limiting the aim of physical science to such description and prediction, it gradually became clear that the method was adequate for the purpose, and over the range of non-living matter, at least, the psychical yielded to the physical. Laws ceased to be commands analogous to legal enactments, and became mere descriptions. But during the passage from one position to the other, by a confusion of thought which may appear strange to us now that we have finished the journey, though no doubt it was inevitable, the purpose and will of which the laws had been the expression were put into the laws themselves ; they were personified and made to will and act. Even now these early stages in the history of thought can be traced by survivals in our language, survivals due to the ascrip- tion of moral qualities to matter. Thus gases are still some- times said to obey or to disobey Boyle’s Law as if it were an enactment for their guidance, and as if it set forth an ideal, the perfect gas, for their imitation. We still hear language which seems to imply that real gases are wanting in perfection, in that they fail to observe the exact letter of the law. I suppose on this view we should have to say that hydrogen is nearest to NO. 1559, VOL. 60] perfection ; but then we should have to regard it as righteous over-much, asort of Pharisee among gases which overshoots the mark in its endeavour to obey the law. Oxygen and nitrogen we may regard as good enough in the affairs of everyday life. But carbon dioxide and chlorine and the like are poor sinners which yield to temptation and liquefy whenever circumstances press at all hardly on them. There is a similar ascription of moral qualities when we judge bodies according to their fulfilment of the purpose for which we use them, when we describe them as good or bad radiators, good or bad insulators, as if it were a duty on their part to radiate well, or insulate well, and as if there were failures on the part of nature to come up to the proper standard. These are of course mere trivialities, but the reaction of language on thought is so subtle and far-reaching that, risking the accusation of pedantry, I would urge the abolition of all such picturesque terms. In our quantitative estimates let us be content with ‘‘high” or ‘‘low,” ‘‘ great’ or ‘‘small,” and let us remember that there is no such thing as a failure to obey @ physical law. A broken law is merely a false description. Concurrently with the change in our conception of physical law has come a change in our conception of physical explana- tion. We have not to go very far back to find such a statement as this—that we have explained anything when we know the cause of it, or when we have found out the reason why—a state- ment which is only appropriate on the psychical view. Without entering into any discussion of the meaning of cause, we can at least assert that that meaning will only have true content when it is concerned with purpose and will. On the purely physical or descriptive view, the idea of cause is quite out of place. In description we are solely concerned with the ‘‘how ” of things, and their ‘‘why” we purposely leave out of account. We explain an event, not when we know ‘‘why”’ it happened. but when we show ‘‘ how ” it is like something else happening else- where or otherwhen—when, in fact, we can include it as a case described by some law already set forth. In explanation, we do not account for the event, but we improve our account of it by likening it to what we already knew. For instance, Newton explained the falling of a stone when he showed that its acceleration towards the earth was similar to and could be expressed by the same law as the acceleration of the moon towards the earth. He explained the air disturbance we call ‘‘sound” when he showed that the motions and forces in the pressure waves were like motions and forces already studied. Franklin explained lightning when and so far as he showed that it was similar in its behaviour to other electric discharges. Here I do not fear any accusation of pedantry in joining those who urge that we should adapt our language to the modern view. It would be a very real gain, a great assistance to clear thinking, if we could entirely abolish the word ‘‘ cause,” in physical de- scription, cease to say ‘‘ why” things happen unless we wish to signify an antecedent purpose, and be content to own that our laws are but expressions of ‘Show ” they occur. The aim of explanation, then, is to reduce the number of laws as far as possible, by showing that laws, at first separated, may be merged in one ; to reduce the number of chapters in the book of science by showing that some are truly mere sub-sections of chapters already written. To take an old but never-worn-out metaphor, the physicist is examining the garment of nature, learning of how many, or rather of how few, different kinds of thread it is woven, finding how each separate thread enters into the pattern, and seeking from the pattern woven in the past to know the pattern yet to come. How many different kinds of thread does nature use ? So far, we have recognised some eight or nine, the number of different forms of energy which we are still obliged to count as distinct. But this distinction we cannot believe to be real. The relations between the different forms of energy, and the fixed rate of exchange when one form gives place to another, encourage us to suppose that if we could only sharpen our senses, or change our point of view, we could effect a still further reduc- tion. We stand in front of nature’s loom as we watch the weaving of the garment ; while we follow a particular thread in the pattern it suddenly disappears, and a thread of another colour takes its place. Is this a new thread, or is it merely the old thread turned round and presenting a new face tous? We can do little more than guess. We cannot get to the other side of the pattern, and our minutest watching will not tell us all the working of the loom. 472 fe Leaving the metaphor, were we true physicists, and physicists -alone, we should, I suppose, be content to describe merely what we observe in the changes of energy. We should say, for instance, that so much kinetic energy ceases, and that so much heat appears, or that so much light comes to a surface, and that so much chemical energy takes its place. But we have to take ourselves as we are, and reckon with the fact that though our material is physical, we ourselves are psychical. And, as a mere matter of fact, we are not content with such dis- continuous descriptions. We dislike the discontinuity and we think of an underlying identity. We think of the heat as being that which a moment before was energy of visible motion, we think of the light as changing its form alone and becoming itself the chemical energy. Then to our passive dislike to discon- tinuity we join our active desire to form a mental picture of what may be going on, a picture like something which we already know. Coming on these discontinuities our ordinary method of explanation fails, for they are not obviously like ‘those series of events in which we can trace every step. We then imagine a constitution of matter and modifications of it corresponding to the different kinds of energy, such that the discontinuities vanish, and such that we can picture one form of energy passing into another and yet keeping the same in kind ‘throughout. We are no longer content to describe what we actually see or feel, but we describe what we imagine we should see or feel if our senses were on quite another scale of magnitude and sensibility. We cease to be physicists of the real and ‘become physicists of the ideal. To form such mental pictures we naturally choose the sense which makes such pictures most definite, the sense of sight, and ‘think of a constitution of matter which shall enable us to explain all the various changes in terms of visible motions and accelera- tions. We imagine a mechanical constitution of the universe. We are encouraged in this attempt by the fact that the rela- tions in this mechanical conception can be so exactly stated, that the equations of motion are so very definite. We have, too, examples of mechanical systems, of which we can give accounts far exceeding in accuracy the accounts of other physical systems. Compare, for instance, the accuracy with which we can describe and foretell the path of a planet with our ignorance of the move- ments of the atmosphere as dependent on the heat of the sun. ‘The planet keeps to the astronomer’s time-table, but the wind still bloweth almost where it listeth. The only foundation which has yet been imagined for this ‘mechanical explanation—if we may use ‘‘ explanation” to denote the likening of our imaginings to that which we actually observe—is the atomic and molecular hypothesis of matter. This hypothesis arose so early in the history of science that we are almost tempted to suppose that it is a necessity of thought, and that it has a warrant of some higher order than any other hypothesis which could be imagined. But I suspect that if we could trace its early development we should find that it arose in an attempt to explain the phenomena of expansion and contraction, evaporation and solution. Were matter a continuum we should have to admit all these as simple facts, inexplicable in that they are like nothing else. But imagine matter to consist of a crowd of separate particles with inter- spaces. Contraction and expansion are then merely a drawing in and a widening out of the crowd. Solution is merely the mingling of two crowds, ‘and evaporation merely a dispersal from the outskirts. The most evident properties of matter are then similar to what may be observed in any public meeting. For ages the molecular hypothesis hardly went further than this. The first step onward was the ascription of vibratory motion to the atoms to explain heat. Then definite qualities were cascribed, definite mutual forces were called into play to explain elasticity and other properties or qualities of matter. But I imagine its first really great achievement was its success in ex- plaining the law of combining proportions, and next to that we should put its success in explaining many of the properties of gases. While light was regarded aS corpuscular—in fact molecular, and while direct action at a distance presented no difficulty, the molecular hypothesis served as the one foundation for the mechanical representation of phenomena. But when it was shown that infinitely the best account of the phenomena of light could be given on the supposition that it consisted of waves, something was needed, as Lord Salisbury has said, to wave, both in the interstellar and in the intermolecular spaces. So the hypothesis of an ether was developed, a necessary comple- NO. 1559, VOL. 60] NATURE [SEPTEMBER 14, 1899 ment of that form of the molecular hypothesis in which matter consists of discrete particles with matter-free intervening spaces. A Then Faraday’s discovery of the influence of the dielectric medium in electric actions led to the general abandonment of the idea of action at a distance, and the ether was called in to aid matter in the explanation of electric and magnetic pheno- mena. The discovery that the velocity of electro-magnetic waves is the same as that of light-waves is at least circumstantial evidence that the same medium transmits both. I suppose we all hope that some time we shall succeed in attributing to this medium such further qualities that it will be able to enlarge its scope and take in the work of gravitation. The mechanical hypothesis has not always taken this dualistic form of material atoms and molecules, floating in a quite distinct ether. I think we may regard Boscovich’s theory of point- centres surrounded by infinitely extending atmospheres of force as really an attempt to get rid of the dualism, and Faraday’s theory of point-centres with radiating lines of force is only Bos- covich’s theory in another form. But Lord Kelvin’s vortex- atom theory gives us a simplification more easily thought of. Here all space is filled with continuous fluid—shall we say a fluid ether 2—and the atoms are mere loci of a particular type of motion of this frictionless fluid. The sole differences in the atoms are differences of position and motion. Where there are whirls, we call the fluid matter ; where there are no whirls, we call it ether. All energy is energy of motion. Our visible kinetic energy, MV?/2, is energy in and round the central whirls; our visible energy of position, our potential energy, is energy of motion in the outlying regions. A similar simplification is given by Dr. Larmor’s hypothesis, in which, again, all space is filled with continuous substance all of one kind, but this time solid rather than fluid. The atoms are loci of strain instead of whirls, and the ether is that which is strained. So, as we watch the weaving of the garment of nature, we resolve it in imagination into threads of ether spangled over with beads of matter. We look still closer, and the beads of matter vanish ; they are mere knots and loops in the threads of ether. The question now faces us—How are we to regard these hypotheses as to the constitution of matter and the connecting ether? How are we to look upon the explanations they afford ? Are we to put atoms and ether on an equal footing with the phenomena observed by our senses, as truths to be investigated for their own sake? Or are they mere tools in the search for truth, liable to be worn out or superseded ? That matter is grained in structure is hardly more than an expression of the fact that in very thin layers it ceases to behave as in thicker layers. But when we pass on from this general statement and give definite form to the granules, or assume definite qualities to the intergranular cement, we are dealing with pure hypotheses. It is hardly possible to think that we shall ever see an atom or handle the ether. We make no attempt whatever to render them evident to the senses. We connect observed conditions and changes in gross visible matter by invisible molecular and ethereal machinery. The changes at each end of the machinery of which we seek to give an account are in gross matter, and this gross matter is our only instrument of detection, and we never receive direct sense-impressions of the imagined atoms or the intervening ether. To strictly descriptive physicists their only use and interest would lie in their service in prediction of the changes which are to take place in gross matter. It appears quite possible that various types of machinery might be devised to produce the known effects. The type we have adopted is undergoing constant minor changes, as new discoveries suggest new arrangements of the parts. Is it utterly beyond possibility that the type itself should change ? The special molecular and ethereal machinery which we have designed, and which we now generally use, has been designed because our most highly developed sense is our sense of sight. Were we otherwise, had we a sense more delicate than sight, one affording us material for more definite mental presentation, we might quite possibly have constructed very different hypo- theses. . Though, as we are, we cannot conceive any higher type than that founded on the sense of sight, we can imagine a lower type, and by way of illustration of the point let us take the sense of which my predecessor spoke last year—the sense of smell, In us it is very undeveloped. But let us imagine a SEPTEMBER 14, 1899] NEAL TCT Ras 473 being in whom it is highly cultivated, say a very intellectual and very hypothetical dog. Let us suppose that he tries to frame an hypothesis as to light. Having found that his sense of smell is excited by surface exhalations, will he not naturally make and be content with a corpuscular theory of light? When he has discovered the facts of dispersion, will he not think of the different colours as different kinds of smell—insensible, perhaps, to him, but sensible to a still more highly gifted, still more hypothetical, dog ? Of course, with our superior intellect and sensibility, we can see where his hypothesis would break down; but unless we are to assume that we have reached finality in sense development, the illustration, grotesque as it may be, will serve to show that our hypotheses are in terms of ourselves rather than in terms of nature itself, they are ejective rather than objective, and so they are to be regarded as instruments, tools, apparatus only to aid us in the search for truth. To use an old analogy—and here we can hardly go except upon analogy—while the building of nature is growing spon- taneously from within, the model of it, which we seek to con- struct in our descriptive science, can only be constructed by means of scaffolding from without, a scaffolding of hypotheses. While in the real building all is continuous, in our model there are detached parts which must be connected with the rest by temporary ladders and passages, or which must be supported till we can see how to fill in the understructure. To give the hypotheses equal validity with facts is to confuse the temporary scaffolding with the building itself. But even if we take this view of the temporary nature of our molecular and ethereal imaginings, it does not lessen their value, their necessity to us. It is merely a true description of ourselves to say that we must believe in the continuity of physical processes, and that we must attempt to form mental pictures of those processes the details of which elude our observation. For such pictures we must frame hypotheses, and we have to use the best material at com- mand in framing them. At present there is only one funda- mental hypothesis—the molecular and ethereal hypothesis —in some such form as is generally accepted. Even if we take the position that the form of the hypothesis may change as our knowledge extends, that we may be able to devise new machinery—nay, even that we may be able to design some quite new type to bring about the same ends— that does not appear to me to lessen the present value of the hypothesis. We can recognise to the full how well it enables us to group together large masses of facts which, without it, would be scattered apart, how it serves to give working explan- ations, and continually enables investigators to think out new questions for research. We can recognise that it is the sym- bolical form in which much actual knowledge is cast. We might almost as well quarrel with the use of the letters of the alphabet, inasmuch as they are not the sounds themselves, but mere arbitrary symbols of the sounds. In this country there is no need for any defence of the use of the molecular hypothesis. But abroad the movement from the position in which hypothesis is confounded with observed truth has carried many through the position of equilibrium equally far on the other side, and a party has been formed which totally abstains from molecules as a protest against immoderate indul- gence in their use. Time will show whether these protesters can do without any hypothesis, whether they can build without scaffolding or ladders. I fear that it is only an attempt to build from balloons. But the protest will have value if it will put us on our guard against using molecules and the ether everywhere and every- where. There is, I think, some danger that we may get so accustomed to picturing everything in terms of these hypotheses that we may come to suppose that we have no firm basis for the facts of observation until we have given a molecular account of them, that a molecular basis is a firmer foundation than direct experience, Let me illustrate this kind of danger. The phenomena of capillarity can, for the most part, be explained on the assumption of a liquid surface tension. But if the subject is treated merely from this point of view, it stands alone—it is a portion of the building of science hanging in the air. The molecular hypo- thesis then comes in to give some explanation of the surface tension, gives, as it were, a supporting understructure con- necting capillarity with other classes of phenomena. But here, } think, the hypothesis should stop, and such phenomena as can NO. 1559, VOL. 60] be explained by the surface tension should be so explained without reference to molecules. They should not be brought in again till the surface-tension explanation fails. It is necessary to bear in mind what part is scaffolding, and what is the building itself, already firm and complete. Or, as another illustration, take the Second Law of Thermo- dynamics. I suspect that it is sometimes supposed that a molecular theory from which the Second Law could be deduced would be a better basis for it than the direct experience on which it was founded by Clausius and Kelvin, or that the mere imagining of a Maxwell’s sorting demon has already disproved the universality of the law ; whereas he is a mere hypothesis grafted on a hypothesis, and nothing corresponding to his action has yet been found. There is more serious danger of confusion of hypothesis with fact in the use of the ether: more risk of failure to see what is accomplished by its aid. In giving an account of light, for instance, the right course, it appears to me, is to describe the phenomena and lay down the laws under which they are grouped, leaving it an open question what it is that waves, until the phenomena oblige us to introduce something more than matter, until we see what properties we must assign to the ether, properties not possessed by matter, in order that it may be competent to afford the explanations we seek. We should then realise more clearly that it is the constitution of matter which we have imagined, the hypothesis of discrete particles which obliges us to assume an intervening medium to carry on the disturbance from particle to particle. But the vortex-atom hypothesis and Dr. Larmor’s strain-atom hypothesis both seem to indicate that we are moving in the direction of the abolition of the distinction between matter and ether, that we shall come to regard the luminiferous medium, not as an attenuated sub- stance here and there encumbered with detached blocks—the molecules of matter—but as something which in certain places exhibits modifications which we term matter. Or starting rather from matter, we may come to think of matter as no longer con- sisting of separated granules, but as a continuum with properties grouped round the centres, which we regard as atoms or molecules. Perhaps I may illustrate the danger in the use of the concep- tion of the ether by considering the common way of describing the electro-magnetic waves, which are all about us here, as ether waves. Now in all cases with which we are acquainted, these waves start from matter ; their energy before starting was, as far as we can guess, energy of the matter between the dif- ferent parts of the source, and they manifest themselves in the receiver as energy of matter. As they travel through the air, I believe that it is quite possible that the electric energy can be expressed in terms of the molecules of air in their path, that they are effecting atomic separations as they go. If so, then the air is quite as much concerned in their propagation as the ether between its molecules. In any case, to term them ether waves is to prejudge the question before we have sufficient evidence. Unless we bear in mind the hypothetical character of our mechanical conception of things, we may run some risk of another danger-—the danger of supposing that we have some- thing more real in mechanical than in other measurements. For instance, there is some risk that the work measure of specific heat should be regarded as more fundamental than the heat measure, in that heat is truly a ‘‘mode of motion.” On the molecular hypothesis, heat is no doubt a mixture of kinetic energy and potential energy of the molecules and their con- stituents, and may even be entirely kinetic energy ; and we may conceivably in the future make the hypothesis so definite that, when we heat a gramme of water I’, we can assign such a fraction of an erg to each atom. But look how much pure hypothesis is here. The real superiority of the work measure of specific heat lies in the fact that it is independent of any particular substance, and there is nothing whatever hypothetical about it. 1 This risk of imagining one particular kind of measure more real than another, more in accordance with the truth of things, may be further illus- trated by the common idea that mass-acceleration is the only way to measure a force. We stand apart from our mechanical system and watch the motions and the accelerations of the various parts, and we find that mass-accelerations have acertain significance in our system, If we keep ourselves outside the system and only use our sense of sight, then mass- acceleration is the only way of describing that behaviour of one body in the presence of others which we term force on it. But if we go about in the system and pull and push bodies, we find that there is another conception of force, in which another sense than sight is concerned—another mode 474 NATURE [SEPTEMBER 14, 1899 Another illustration of the illegitimate use of our hypothesis, as it appears to me, is in the attempt to find in the ether a fixed datum for the measurement of material velocities and acceler- ations, a something in which we can draw our coordinate axes so that they will never turn or bend. But this is as if, dis- contented with the movement of the earth’s pole, we should seek to find our zero lines of latitude and longitude in the Atlantic Ocean. Leaving out of sight the possibility of ethereal currents which we cannot detect, and the motions due to every ray of light which traverses space, we could only fix positions and directions in the ether by buoying them with matter. We know nothing of the ether, except by its effects on matter, and, after all, it would be the material buoys which would fix the positions and not the ether in which they float. The discussion of the physical method, with its descriptive laws and explanations, and its hypothetical extension of description, leads us on to the consideration of the limitation of its range. The method was developed in the study of matter which we describe as non-living, and with non-living matter the method has sufficed for the particular purposes of the physicist. Of course only a little corner of the universe has been explored, but in the study of non-living matter we have come to no impassable gulfs, no chasms across which we cannot throw bridges of hypothesis. Does the method equally suffice when it is applied to living matter? Can we give a purely physical account of such matter, likening its motions and changes to other motions and changes already observed, and so explaining them ? Can we group them in laws which will enable us to predict future conditions and positions? The ancient question never answered, but never ceasing to press for an answer. Having faith in our descriptive method, let us use it to describe our real attitude on the question. Do we, or do we not, as a matter of fact, make any attempt to apply the physical method to describe and explain those motions of matter which on the psychical view we term voluntary ? Any commonplace example, and the more commonplace the more is it to the point, will at once tell us our practice, whatever may be our theory, For instance, a steamer is going across the Channel. We can give a fairly good physical account of the motion of the steamer. We can describe how the energy stored in the coal passes out through the boiler into the machinery, and how it is ultimately absorbed by the sea. And the machinery once started, we can give an account of the actions and reactions between its various parts and the water, and if only the crew will not interfere, we can predict with some approach to correctness how the vessel will run. All these processes can be likened to processes already studied— perhaps on another scale—in our laboratories, and from the similarities prediction is possible. But now think of a passenger on board who has received an invitation to take the journey. It is simply a matter of fact that we make no attempt at a com- plete physical account and explanation of those actions which he takes to accomplish his purpose. We trace no lines of in- duction in the ether connecting him with his friends acrcss the Channel, we seek no law of force under which he moves. In practice the strictest physicist abandons the physical view, and replaces it by the psychical. He admits the study of purpose as well as the study of motion. He has to admit that here his physical method of prediction fails. In physical observations one set of measurements may lead to the prediction of the results of another set of measure- ments. The equations expressing the laws imply different ob- servations with some definite relation between their results, and if we know one set of observations and that definite relation we can predict the result of the other set. But if we take the psychical view of actions, we can only measure the actions. We have no independent means of studying and measuring the motions which preceded the actions, we can ‘only estimate their value by the consequent actions. If we formed equations, they would be mere identities with the same terms on either side. The consistent and persistent physicist, finding the door closed against him, finding that he has hardly a sphere of in- fluence left to him in the psychical region, seeks to apply his methods in another way by assuming that if he knew all about the molecular positions and motions in the living matter, then the ordinary physical laws could be applied and the physical of measurement much more ancient and still far more extensively used —the measurement by weight supported. Each method has its own range; each is fundamental in that range. It is one of the great practical problems n physics to make the pendulum give us the exact ratio of the units in the Wo systems. NO. 1559, VOL. 60] conditions at any future time could be predicted. He would say, I suppose, with regard to the Channel passenger, that it is absurd to begin with the most complicated mechanism, and seek to give a physical account of that. He would urge that we should take some lower form of life where the structure and motions are simpler, and apply the physical methods to that. Well, then, let us look for the physical explanation of any motion which we are entitled from its likeness to our own action to call a voluntary motion. Must we not own that even the very beginning of such explanation is as yet non-existent ? It appears to me that the assumption that our methods do apply, and that purely physical explanation will suffice to predict all motions and changes, voluntary and involuntary, is at present simply a gigantic extra-polation, which we should unhesitatingly reject if it were merely a case of ordinary physical investigation. The physicist when thus extending his range is ceasing to be a physicist, ceasing to be content with his descriptive methods in his intense desire to show that he is a physicist throughout. Of course we may describe the motions and changes of any type of matter after the event, and in a purely physical manner. And as Prof. Ward has suggested, in a most im- portant contribution to this subject which he has made in his recently published ‘‘ Gifford Lectures” (‘‘ Naturalism and Agnosticism,” Zhe Gifford Lectures, 1896-98, vol. ii. p. 71), where ordinary physical explanations fail to give an account of the motions, we might imagine some structure in the ether, and such stresses between the ether and matter that our physical explanations should still hold. But, as Prof. Ward says, such ethereal constructions would present no warrant for their reality or consistency. Indeed they would be mere images in the surface of things to account for what goes on in front of the surface, and would have no more reality than the images of objects in a glass. If we have full confidence in the descriptive method, as ap- plied to living and non-living matter, it appears to me that up to the present it teaches us that while in non-living matter we can always find similarities, that, while each event is like other events, actual or imagined, in a living being there are always dissimilarities. Taking the psychical view—the only view which we really do at present take—in the living being there is always some individuality, something different from any other living being, and full prediction in the physical sense, and by physical methods, is impossible. If this be true, the loom of nature is weaving a pattern with no mere geometrical design, The threads of life, coming in we know not where, now twining together, now dividing, are weaving patterns of their own, ever increasing in intricacy, ever gaining in beauty. 5 Ei CaO uN, B: CHEMISTRY. OPENING ApbDREss BY Dr. Horace T. Brown, F.R.S., PRESIDENT OF THE SECTION. THE subject which I have chosen for my Address is the fixation of carbon by plants, one which is the common meeting ground of chemistry, physics and biology. I must, however, confine myself only to certain aspects of the question, since it is manifestly impossible to fully discuss the whole of a subject of such magnitude and importance within the time at my disposal. We have become so accustomed to the idea that the higher plants derive ¢4e whole of their carbon from atmospheric sources that we are apt to forget how very indirect is the nature of much of the experimental evidence on which this belief is founded. There can, of course, be no doubt that the primary source of the organic carbon of the soil, and of the plants grow- ing on it, is the atmosphere; but of late years there has been such an accumulation of evidence tending to show that the higher plants are capable of being nourished by the direct ap- plication of a great variety of ready-formed organic compounds, that we are justified in demanding further proof that the stores of organic substances in the soil must necessarily be oxidised down to the lowest possible point before their carbon is once more in a fit state to be assimilated. It was the hope of gaining more direct evidence on this im- portant question which led me some time ago to attack the problem experimentally in conjunction with Mr. F. Escombe, the resources of the Jodrell Laboratory at Kew having been SEPTEMBER 14, 1899] vid TORE 475 kindly put at our disposal by Sir W. Thiselton-Dyer and Dr. D. H. Scott. Up to the present time our experiments have not been carried far enough to enable us to give a positive answer to the main question, but they have already suggested a new method of attack which will enable us in the future to deter- mine, with a fair amount of certainty, whether any particular plant, growing under perfectly natural conditions, derives any appreciable portion of its carbon from any other source than the gaseous carbon dioxide of the atmosphere. During the course of the inquiry, many interesting side issues frave been raised which we believe to be of some importance in their bearing on the processes of plant nutrition, and it is to a consideration of these that I intend to devote the greater part of my Address. / I must, however, in the first place indulge in a little historical retrospect, and am the more tempted to do this, as far as the early pioneers in this branch of knowledge are concerned, since a critical study of their writings has shown me very clearly that the relative merits of some of these older workers, and the re- spective parts which they took in founding the true theory of assimilation, have in our own time been much misrepresented by more than one historian of science whose name carries great weight. 5; There is no chapter in the history of scientific discovery of greater abiding interest than that which was opened by Priestley in 1771, when he commenced his work on the influence of plants on the composition of the air around them. It has often been assumed that these experiments of Priestley, which were unquestionably the starting-point for all succeeding workers, were the result of some haphazard method of working, and of ‘one of those happy chances to which he is in the habit of attri- ‘buting some of his most important discoveries. However much the element of chance entered into some of his work, and in this vespect I think Priestley often does himself injustice, the dis- covery of the amelioration of vitiated air by plants was certainly not a case of this kind. Of all his contemporaries belonging to the old school of chemistry, Priestley had the clearest conception of the processes of animal respiration and of their identity with the process of combustion. This is clearly shown by his ‘‘Observations on Respiration and the Use of the Blood,” which he presented to the Royal Society in 1776 This memoir, avritten of course from the phlogistic point of view, only requires translating into the language of the newer chemistry to be an accurate statement of the main facts of animal respiration. We have it on Priestley’s own authority that it was these studies which produced in his mind a conviction that there must be some provision in nature for dephlogisticating the air which was constantly being vitiated by the processes of respiration, com- bustion and putrefaction, and for rendering it once more fit for maintaining animal life. In his search for this compensating influence, which he justly regarded as one of the most important problems of natural philosophy, he made many attempts to bring back the vitiated air to its original state by agitating it with water, and by submitting it to the continued action of light and heat, and it was in the course of these systematic attempts that he was led to study the influence of plants in this direction. It was in the month of August 1771 that he made the memorable experiments at Leeds of immersing sprigs of mint in air which had been vitiated by the burning of a candle or by animal respiration. To quote his own words, this observation fed him ‘‘to conclude that plants, instead of affecting the air in the same manner with animal respiration, reverse the effects of breathing, and tend to keep the atmosphere sweet and whole- some when it is become noxious in consequence of animals either living or breathing, or dying and putrefying in it.” That he was fully convinced that these observations, which he re- peated and amplified in the following year, presented the true key to the problem, is sufficiently shown by another passage in which he says: ‘‘ These proofs of the partial restoration of air by plants in a state of vegetation, though ina confined and | annatural situation, cannot but render it highly probable that the injury which is continually done to the atmosphere by the respiration of sucha number of animals, and the putrefaction | of such masses of both vegetable and animal matter, is, in part at least, repaired by the vegetable creation ; and notwithstand- ing the prodigious mass of air that is corrupted daily by the above causes, yet if we consider the immense profusion of vege- tables upon the face of the earth growing in places suited to | their nature, and consequently at full liberty to exert all their powers, both inhaling and exhaling, it can hardly be thought NO. 1559, VOL. 60} but that it may be a sufficient counterbalance to it, and that the remedy is adequate to the evil.” Between the time of Priestley temporarily relinquishing his experiments in this direction in 1772 and his resumption of them in 1778, owing to the adverse criticism of Scheele and others, he had discovered dephlogisticated air or oxygen, and had elaborated his method for ascertaining the purity of air, or its richness in oxygen, by determining its diminution in volume after mixing with an excess of nitric oxide over water.' This method gave, of course, a much greater degree of precision to his results than was attainable in his earlier work, where the purity of the air at the end of an experiment was only deter- mined by ascertaining if it would support the combustion of a candle or allow a small animal to live in it. The results of his later work were published in 1779, and were not altogether confirmatory of those arrived at six years before. It is true that he generally found evidence of an evo- lution of oxygen by the plants, but occasionally the air was less “pure” at the end of an experiment than it was at the begin- ning, and this occurred in a sufficient number of cases to Dr. Priestley to doubt to some extent the accuracy of his previous conclusions. On the whole, however, he still thinks it p, obadble that the vegetation of healthy plants has a salutary effect on the air in which they grow. The reason for this want of complete consistency in these later experiments was, of course, his failure at that time to re- cognise the important influence of /zg/¢ in bringing about the evolution of oxygen, an explanation which was given shortly afterwards by Ingen-Housz. Priestley’s attention was now taken up with another observ- ation, which led him within a very short distance indeed of the discovery that the evolution of oxygen by plants is conditioned, not only by a sufficient degree of illumination, but also by the pre-existence of carbon dioxide. It is the more necessary to treat of this point somewhat in detail, since it is a part of his work which has received but scanty justice at the hands of recent writers, who have apparently failed to see how much our modern conceptions of plant nutrition really owe to the initiative of Priestley. In his ‘‘ History of Botany,” Sachs deals very unfairly with Priestley in this respect, owing to a want of in- timate knowledge of his writings, and to the lack of anything like perspective in estimating the relative merits of his con- temporaries Ingen-Housz and Senebier, whose position can only be completely understood after a careful study of their numerous original memoirs, some of which are by no means readily accessible. In the course of his experiments on plants partially immersed in water more or less fully impregnated with ‘fixed air,” Priestley had observed a fact which had not escaped the notice of Bonnet at an earlier date, that bubbles of gas arose spon- taneously from the leaves and stems, and it occurred to him that an examination of the nature of this gas by means of his new eudiometric process ought to settle the question whether plants really do contribute in any way to the purification of ordinary air. It was in June 1778 that he put this to the test, and he found that the air thus liberated was much richer in oxygen than ordinary air. On removing the plants, he found to his astonishment that the water in which they had been placed, and which had a considerable amount of ‘‘ green matter’’ adhering to the sides of the phials, still continued to evolve a gas which increased in amount when the vessels were placed in sunlight. On testing this gas with his eudiometric process, he found that it consisted to a great extent of ‘‘dephlogisticated air” or oxygen ; in fact, from the experimental results which he gives it is evident that the gas contained from 74 to 85 per cent. of oxygen. Having observed that the ‘‘ green matter” appeared much more readily in pump water than in rain or river water, and knowing that pump water contained consider- able amounts of ‘*fixed air,” he was led to make a series of experiments with water artificially impregnated with carbon dioxide, which left no doubt in his mind thit the production of the ‘‘ green matter,” and the evolution of the dephlogisticated air were in some way due to the presence of ‘‘ fixed air.” Up to this point Priestley was following a path which seemed about to lead him to a complete solution of his previous difficulties. He had beyond all question succeeded in showing that the evolution of oxygen was not only dependent on the _pre- existence of carbon dioxide, but that light was also required 1 Nitric oxide was discovered by Priestley in 1772, and was described by him under the name of ‘‘nitrous air.” 476 NATURE [SEPTEMBER 14, 1899 for the process. It only wanted, in fact, the recognition of the vegetable nature of the alga which constituted his ‘green substance” to bring these observations into line with his previous work, and to complete a discovery which would have eclipsed in importance all the others with which Priestley’s name is associated, It was just this one step which he most provok- ingly failed to take. It is true that he examined the “‘green substance”? under the microscope, but owing to want of skill in the use of the instrument, and also to his defective eye- sight, he was unable to determine its true nature, and unfor- tunately adopted the view that it had merely a mechanical action in separating the oxygen from the water, and, to use his own words, that ‘it was only a circumstance preceding the spontaneous emission of the air from water.” He was, in fact, now inclined to regard the process as a purely chemical one, due to the direct action of light on the carbon dioxide dissolved in the water. But this was by no means Priestley’s final view, as shown by a further description of his experiments on plants set forth in the new edition of his works published in 1790, where he clearly recognised the error into which he had been led.1_ Mean- while the subject had been taken up by two other observers, Ingen: Housz and Senebier, and in order to thoroughly under- siand the respective shares which these men took in advancing our knowledge of the assimilatory process, it is necessary to consult, not only their books, but also the numerous scattered memoirs which appeared at intervals between the years 1779 and 1800. To Ingen-Housz must unquestionably be awarded the merit of having experimentally demonstrated that the amelioration of the surrounding air by plants is not, as Priestley at first believed, due to vegetative action fev se, but is dependent on the access of light of a sufficient degree of intensity, and, moreover, that the power is confined to the green parts of the plants. At the same time, whilst recognising, as Priestley had done before him, that the combined action of plants and light on the air was a dephlogisticating process, he did not know, until after its demonstration by Senebier, that the particular form of phlo- gisticated air which was essential to plants was “‘ fixed air” or carbon dioxide. In fact, Ingen-Housz had but a slender know- ledge of the chemistry of his day, so much so indeed that he constantly confuses ‘‘ phlogisticated air”’ or nitrogen with ‘‘ fixed air,” and attributes the source of the evolved oxygen either to air imprisoned within the leaf, or, in the case of submerged plants, to a metamorphosis of the water itself. I must, how- ever, recall the fact that Ingen-Housz was the first to show that the green parts of plants in the dark, and the roots both in the light and in darkness, vitiate the air in the same way as animals do. On the strength of these experiments, he is gener- ally given credit for having first observed the true respiration of plants, but I cannot avoid the conclusion that, in the con- troversy which ensued on this point between Ingen-Housz and Senebier, the adverse criticisms of the latter were well- founded. Whilst not denying that plants in the dark have some mephitic influence on the air around them, Senebier maintained that the greater part of the observed effect was due to a fermentative action set up in the large bulk of leaves which Ingen-Housz employed. Certainly some of the results appear to be largely in excess of those we should now expect to obtain from respiratory processes only.” Senebier’s work falls between the years 1782 and 1800. The fact that he was an early convert to the new ideas and general- isations of Lavoisier gives his views on plant nutrition far greater precision than those of Priestley and Ingen-Housz. His experiments, for the most part well devised, proved 1 The view which was taken by Priestley’s contemporaries of his position with regard to the discovery of the fundamental facts is well exemplified by the following remarks taken from a paper published by Ingen-Housz in 1784 (Annales de Physigue, xxiv. 44). ‘C'est A M. Priestley seul que nous devons la grande découverte que les végétaux possédent le pouvoir de cor- riger l’air mauyais et d’ameliorer |'air commun: c'est lui quinous en a ouvert la porte. J'ai été assez constamment attaché & ce beau systéme, dans le temps que lui méme, par trop peu de prédilection pour ses propres opinions, paroissoit chanceler.” 2 It is by.no means uncommon to find Ingen-Housz put forward as the discoverer of the fixation of carbon by plants from carbon dioxide. This claim is generally based on certain statements made in his essay on the ““Food Plants and the Renovation of the Soil,” published in 1796 as an appendix to the outlines of the fifteenth chapter of the ‘‘ Proposed General Report from the Board of Agriculture.” All that is good and sound in this essay is taken from Senebier’s papers without any acknowledgment, but, in appropriating ideas which he evidently understands very imperfectly, he has built up a system of plant economy which is almost unintelligible. NO. 1559, VOL. 60] beyond all doubt that the oxygen disengaged from submerged) and isolated plants could not be derived from air contained in the leaf parenchyma, but that it depended on the pre- existence of carbon dioxide, and that its evolution was strictly proportional to the amount of carbon dioxide which the water contained. ; Although positive experimental proof was still wanting that aérial plants also derive their carbon from carbon dioxide, Senebier regarded this as extremely probable; but, taking into consideration the small amount of this gas present in the atmosphere, he concluded that it must reach the plant by the roots and leaves entirely ina state of solution in water. The work of Priestley, Senebier, and Ingen-Housz fortunately attracted the attention of a young chemist of high attainments, who, within a period of less than ten years, did more for the advancement of vegetable physiology than any single observer before or since his time. Théodore de Saussure, the second of that illustrious name, and the son of the famous explorer and natural philosopher, commenced his researches about the year 1796, and in 1804 published his ‘‘ Recherches Chimiques sur la Végétation,” a modest little octavo volume of some 300 pages which must certainly take rank as one of the great classics of scientific literature, and one of the most remarkable books of the century. De Saussure was a past master in the art of experiment, and the methods which he devised for demonstrating the influence of water, air and soil on vegetation have been the models on which all such investigations have been conducted ever since. It is indeed very difficult, when reading this masterly essay, to bear in mind that it was not written fifty or sixty years later than the date on its title-page, so essentially modern are its modes of expression and reasoning, and so far is the author in advance of his contemporaries. It is to this work we must refer for the first experimental proof that plants derive at any rate the greater part of their carbon from the surrounding atmosphere. This was shown by De Saussure by a variety of quantitative experi- ments of a sufficient degree of accuracy to bring out the great leading facts. By making known mixtures of carbon dioxide and air, and submitting them to the action of plants in sunlight, he was able, not only to show that the gaseous carbon dioxide was decomposed and the carbon assimilated, but also that the volume of oxygen disengaged was approximately equal to that of the carbon dioxide decomposed. He also showed that plants growing in the open in moist sand, or in distilled water, and therefore under conditions in which they could not derive any carbon from other than atmospheric sources, not only materially increased in dry weight, but contained much more carbon at the close of the experiment than at the beginning, and had also fixed an appreciable amount of water in the process. That atmospheric carbon dioxide is not only bene- ficial to plants in sunlight, but is also essential to their very existence, De Saussure proved by introducing an absorbent of this gas into the vessel containing a plant or the branch of a tree rooted naturally in the soil. Under these conditions, the portions of the plant enclosed always died. He also ascertained by experiment the increase in dry weight of a sunflower plant during four months of natural growth ; and knowing approximately the amount of water transpired during that period, and the maximum amount of solids which this transpired water could possibly introduce into the plant, he calculated that these solids, and the carbon dioxide in solu- tion in the transpiration water, fell far short of accounting for the observed increase in the dry weight of the plant. This increase must, therefore, be mainly due to the fixation of atmospheric carbon dioxide and water. It is certainly a remarkable fact that the rigid experimental proofs which De Saussure brought forward in support of his views did not carry conviction to the minds of every one. His book, however, suffered the fate of many others which have appeared in advance of their time. It is true that De Saussure’s doctrines were always kept alive by the advanced physiologists of the French school, such as De Candolle and Dutrochet, but when Liebig first turned his attention to the subject he found the field in possession of the humus theory of Treviranus, a theory which no longer took any account of the decomposition of carbon dioxide by the leaves, but which de- 1 Although clearly indicating that no change of volume occurred in the mixture of air and carbon dioxide so treated, his final analytical results show a small apparent evolution of nitrogen. This was due to the eudio- metric methods he employed, methods, it is true, far superior in point of accuracy to those of his predecessors, but still necessarily imperfect. SEPTEMBER 14, 1899] NATURE 477 rived the whole of the elements of the growing plant from a solution of the soil extract taken up by the roots. We may well say with Sachs, ‘‘nothing can be conceived more deplorable than this theory of nutrition ; it would have been bad at the end of the seventeenth century, it is difficult to believe that it could have been published thirty years after De Saussure’s work.” It is well known how by the cogency of his reasoning and the force of his genius Liebig successfully overthrew this heresy, and once more established the doctrine of carbon assimilation as taught by De Saussure; and the accurate work of Boussingauit, who, whilst elaborating far more delicate analytical processes than were possessed by chemists in the early days of the century, still in the main used De Saussure’s methods, gave the final death-blow to the humus theory, at any rate in the crude form in which it was presented by its originators. No one since that time has questioned the fact that green plants owe the greater part of their carbon to atmospheric sources, and the accumulated experience of two succeeding generations of workers has added proof on proof of the correctness of this great generalisation. But whilst it cannot be doubted that green plants devoid of parasitic or saprophytic habit derive the principal part of their carbon from the air, is the experimental evidence at present so complete as to exclude all other sources of supply? De Saussure himself certainly left the door open to such a possi- bility, and although Boussingault held a different view, we find Sachs as late as 1865 maintaining that it is not contrary to the generally accepted theory of assimilation to suppose that there are chlorophyllous plants which decompose carbon dioxide and at the same time absorb ready-formed organic substances whose carbon they utilise in the formation of new organs. Up to comparatively recently there was little or no experi- mental evidence to justify this supposition, for the early ex- periments of De Saussure on the influence of solutions of sugar, and of other organic substances, on growing plants, although very suggestive, were not of a sufficiently precise nature to lead to any conclusions, and we must come down to within fiftteen years of the present time for anything like a demonstration that the green organs of plants can, under favourable conditions, build up their tissue from already elaborated carbon compounds just as do the fungi and the non-chlorophyllous plants generally. The active centres of the decomposition of carbon dioxide in green leaves are the chlorophyll corpuscles or chloroplastids, and the first visible indication of this decomposition is the formation within these chloroplastids of minute granules of starch whose presence can be shown by suitable micro-chemical means. I have elsewhere discussed the question of how far the appearance of this starch is dependent on the pre-existence of other carbohydrates of a simpler constitution, and also the probability that the whole of the products of assimilation do not necessarily pass through the form of starch: this is a subject which need scarcely concern us at the present moment; it is sufficient to draw attention to the main fact that in an assim- ilating cell the chloroplastids, in the vast majority of cases, give rise to these minute starch granules, which once more disappear when the plant is placed in darkness, or when the air around it is deprived of carbon dioxide. Now in 1883 Bohm made the interesting discovery that when green leaves are placed in thedark until the starchof their chloroplastids has completely disappeared, there is a reappearance of starch when the cut end of the leaf-stalk is immersed in a solution of cane sugar and of dextrose, or when the leaf is brought directly in contact with solutions of these substances. He found, in fact, that the elements of the cell which, under ordinary circumstances, manu- facture their materials for plant growth by the reduction of carbon dioxide under the influence of sunlight, can, under other conditions, supply their requirements from suitable ready-formed organic substances. These observations of Bohm were fully confirmed two years later by Schimper, and were subsequently much extended by A. Meyer and E. Laurent, who found that fructose, maltose, mannitol, dulcitol, and glycerol could also contribute directly to the nutrition of leaves. Bokorny, working with Sfzvogyra immersed in dilute solu- tions, found that starch production in the chlorophyll bodies could be induced by a large number of organic substances, in- cluding, amongst many others, asparagin, citric, tartaric, and lactic acids, leucine, tyrosine, and peptone. 1 By far the most interesting and important result of Bokorny is the proof he gives that formaldehyde is directly assimilable by Spirogyra. His early attempts to show this had been rendered abortive by the highly poisonous NO. 1559, VOL. 60] Very much more to the point are the experiments of Acton, made in 1889, and the still more recent work of J. Laurent and of Mazé. In his experiments on terrestrial plants, Acton, after depleting them of starch, immersed the cut branches or roots, as the case might be, in culture fluids containing certain organic substances, and took precautions to prevent any normal assimilation from taking place by depriving the airaround the plant of any trace of carbon dioxide. He was not able to show the direct nutritive in- fluence of so large a range of substances as Bokorny had done for Spirogyra, but his results leave no room for doubt that several of the carbohydrates, and even glycerine, can be absorbed by the roots, and can contribute to the nutrition of the green parts. Acton tried, amongst other substances, an ‘‘ extract of natural humus,” which was an aqueous solution of the extractives of a light soil which are soluble in dilute alcohol. This extract was found to be effective in producing a small quantity of starch in the leaves, and it evidently contained some substance or sub- stances directly assimilable by the plant. Apparently without knowing anything of this work of Acton, J. Laurent has recently made a series of experiments on the culture of the maize plant in mineral solutions containing sac- charose, glucose, or invert-sugar, and in this way has not only obtained, as Acton had done before him, evidence of the active formation of starch in the leaves, but has also found a very notable increase in the dry weight of the plant. Although as- similation of the carbohydrate may under these circumstances go on in darkness, Laurent found that the process was much enhanced when light had access tothe plant. Mazé, within the last few months, has obtained even more pronounced effects of this kind. When all these new facts are taken into consideration, I think they justify what I have already said, that we ought to demand more direct evidence than is at present available before we accept the view that the majority of chlorophyllous plants take in the whole of their carbon from the atmosphere. In the cycle of change which the organic matter of the soil is constantly undergoing under the influence of micro-organisms, it seems by no means improbable that intermediate substances may be formed which in some measure directly contribute to the nutri- tion of the higher plants, and we must also by no means lose sight of the possible effect, in the same direction, of the symbiotic union of certain fungi with the root extremities of many plants, the Mycorhizz, whose functions are still so imperfectly under- stood. Then, again, we must remember that we have another possible extra-atmospheric source of carbon dioxide in the transpiration water of the plant, which is derived from a soil whose gases may contain 5 per cent. or more of carbon dioxide. From the amount of water transpired in a given time, and an application of the law of partial pressures, it may be readily shown that the supply of carbon dioxide to the aérial organs of a plant from this source is by no means negligible. Before these problems can be attacked for a particular plant with any hope of success, it is clear that we must have some means of establishing an accurate debtor and creditor account as between the plant and the surrounding atmosphere, and this account must extend over a sufficiently long period, and allow of an accurate balance being struck with the amount of carbon found in the plant at the end of the experiment. Up to within a few years ago we had no means of even ap- proximately determining the actual rate at which the assimilatory process goes on in a plant other than that afforded by its increase in weight in a given time. Such experiments, necessarily ex- tending over weeks or months, can, at the best, only give us certain average results, and consequently afford no measure of the activity of assimilation under fixed conditions of insolation. In the year 1884, Sachs, who had for some time been at work on the formation of starch in leaves under the action of sunlight, found that the accumulation of freshly assimilated material in a leaf may, under favourable conditions, go on so rapidly as to give rise to a very appreciable increase of weight in the leaf lamina within the short space of a few hours. By observing at nature of this substance. The difficulty was surmounted by using a dilute solution of sodium oxymethylsulphonate, which ‘on warming with water splits up into formaldehyde and acid sodium sulphite. To prevent the un- favourable action of the acid sodium sulphite, dipotassium or disodium phosphate was added to the plant cultures. In such a solution, with rigid exclusion of carbon dioxide, Spirogyra majyuscula forms starch in its chlorophyll bodies, but the access of light appears to be necessary. The importance of this experiment is very great in connection with Baeyer’s well-known hypothesis that the first act of assimilation is the reduction of carbon dioxide and water to the state of formaldehyde. 478 NAD ORE: [SEPTEMBER 14, 1899 different times of the day the varying dry weight of equal areas of large leaves, Sachs obtained an approximate measure of the rate of the assimilatory process which he could express in terms of actual number of grams of substance assimilated by a unit area of leaf in unit of time. In thismannerhe was able to show, for instance, that a sunflower leaf, whilst still attached to the plant, increases in weight when exposed to bright sunshine at the hourly rate of about one gram persquare metre of leaf area. In the case of similar leaves detached from the plant, and of course under conditions in which the products of assimilation were entirely accumulated in the leaf, he found an increase in weight of rather more than 14 grams per square metre per hour. I was able to confirm this work of Sachs in the course of an investigation on the Chemistry of Leaves which I made with Dr. G. H. Morris in 1892-93, and there can be no doubt that the variations in the weight of leaves can be used asa fair index of the activity of a leaf in assimilating, but it is not a method which admits of much refinement of accuracy, owing, amongst other things, to the want of perfect symmetry in the leaves as regards thickness and density of the lamine and to the possible migration of the assimilated material into the larger ribs, which of course cannot be included in the weighings. It is evident that a far better plan of measuring the rate of assimilation under varying conditions would be the estimation of the actual amount of carbon dioxide entering a given area of the leaf in a certain time, and it was to the perfection of a method of this kind that Mr. Escombe and I first turned our attention. In all previous attempts to measure the rate of ingress of carbon dioxide, suchas those of Corenwinder, and more recently still of Mr. F. F. Blackman, it has been necessary to use air containing comparatively large quantities of carbon dioxide, amounting to 4 per cent. and upwards. Interesting and useful as such experiments undoubtedly are from the point of view from which they were undertaken, we must not lose sight of the fact that such conditions are highly artificial, and very far re- moved from those under which a plant finds itself in the natural state. where its leaves are bathed with air containing, not 4 or 5 per cent., but only ‘03 per cent. of carbon dioxide. I shall have occasion later on to show how remarkably the rate of intake of carbon dioxide into a plant is influenced by extremely small variations in the tension of that gas, and that on this account no deduction can be drawn as to the rate of assimilation under natural conditions from any experiments in which the air con- tains even so small an amount of carbon dioxide as I per cent. Before proceeding further in this direction, however, it will be well to consider the amount of carbon dioxide which must enter a leaf in a given time in order to produce an influence on its weight comparable with that indicated by the Sachs method of weighing definite areas. For this purpose I will consider a leaf with which we have made many experiments—that of Cata/pa bignonzoides. \t is a very symmetrical leaf anda good assimilator, and since the intake of carbon dioxide takes place only on the under side, the question to which I wish to draw your attention zan be stated in a simple manner. When such a leaf is subjected o a modified form of the half-leaf weighing method of Sachs, ito the details of which I cannot here enter, it may, under favourable conditions, show an increase in dry weight equal to about one gram per square metre per hour. Since this increase in weight is due almost entirely to the formation of carbohydrates, we can calculate with a close approximation to accuracy the corresponding amount of carbon dioxide. This will of course depend, within certain narrow limits, on the nature of the carbohydrate formed. The formation of a gram of starch requires 1°628 grams of carbon dioxide, whilst an equal amount of a C,H,,0,% or a CjgH..O,, sugar require 1°466 and 1°543 grams respectively. From the knowledge we possess of the nature of the carbohydrates of the leaf, we are quite sure that the mean of these values, that is 1°545 grams, must be very near the truth. This amount corresponds to 784 c.c. of carbon dioxide at normal temperature and pressure, which must repre- sent the volume abstracted by the square metre of leaf surface in one hour from air containing only three parts of carbon dioxide in 10,000, supposing the method of leaf weighing to give correct results. We shall see later on that this intake can be verified by direct estimations ; it is equivalent to the total amount of carbon dioxide in a column of air of a cross section equal to that of the leaf, and of a height of 26 decimetres. The extraordinary power which an assimilating leaf possesses of abstracting carbon dioxide from the air is best shown by comparing it with an equal area of a freely exposed solution of NO. 1559, VOL. 60] | caustic alkali. We have made a very large number of experi- ments on the rate at which atmospheric carbon dioxide can be taken up by a solution of caustic soda under varying conditions, and have been surprised to find how constant the absorption is. In a moderately still air a square metre of surface of such a freely exposed solution will absorb about 1200 c.c. of carbon dioxide per hour, and this can only be increased to about 1500 c.c. even if the dish is exposed to the full influence of a strong wind out in the open. When the surface of the liquid is constantly renewed during the experiment by means of a mechanical stirrer, the rate of absorption is not sensibly affected, providing the agitation does not appreciably increase the surface area, and considerable variations in the strength of the alkaline solution are also without any effect. On the other hand, slight variations in the tension of the carbon dioxide of the air have a marked influence on the rate of absorption, and in order to study this point we have constructed an apparatus which allows us to pass over an absorptive surface of liquid a current of air in a stratum of known thickness, and with a known average velocity. By introducing definite amounts of carbon dioxide into this stream of air we have been able to determine the influence of its tension on the rate of absorption, At present we have only employed air containing amounts varying from o’8 to 13 parts per 10,000, that is to say, from about one-quarter to a little more than four times the amount contained in normal air. Within these limits, and probably beyond them, the rate of absorption by the alkaline surface is strictly proportional to the tension of the carbon dioxide in the air current. I shall have occasion to show later on that the same rule holds good with regard to an assimilating leaf, and that in this case also, within certain limits, the intake of the gas is proportional to its tension. The fact which I wish more particularly to bring out in these comparisons is that a leaf surface which is assimilating at the rate of one gram of carbohydrate per square metre per hour is absorbing atmospheric carbon dioxide more than half as fast as the same surface would do if wetted with a constantly renewed film of a strong solution of caustic alkale. From what I have just said about the influence of tension on the absorption of carbon dioxide by an assimilating leaf, it is clear that any attempts to determine by direct means the natural intake of that gas during assimilation must be made with ordinary air, and that such experiments can only be carried out on a comparatively large scale. We had in the first instance to devise an apparatus which would rapidly and completely absorb the whole of the carbon dioxide from a stream of air passing through it at the rate of from 100 to 200 litres per hour, and at the same time admit of an extremely accurate determination of the absorbed carbon dioxide. The absorbing apparatus which we finally adopted is a modi- fication of one used by Reiset in his estimations of the carbon dioxide of the atmosphere. It consists essentially of a glass tube 50 cm. long, fixed vertically in a wide-mouthed glass vessel furnished with a second aperture and tubulure. ‘The height of the vertical tube is invariable, but its width is regulated according to the amount of air required to be drawn through the apparatus in a given time. The bottom of this tube is closed with a platinum or silver plate pierced with a large number of very small holes, and two other similar perforated plates are inserted in the tube at certain intervals. The upper part of the tube is put in connection with an aspirating water-pump, and the absorbing liquid is placed in the lower glass vessel, whose second tubulure is connected with the supply of air in which the carbon dioxide has to be determined. When the aspirator is started the liquid is first drawn up into the vertical tube, and the air then follows through the perforated plates which act as *scrubbers."” Reiset, in his work, used baryta water as the absorbent, an aliquot part of which was titrated before and after the experiment, the changes in the volume of the liquid being corrected for by certain devices which I need not describe. The efficiency of the apparatus as a complete absorber of atmospheric carbon dioxide leaves nothing to be desired, but in dealing with large quantities of baryta solution, amounting to 400 c.c. or more, the errors due to inaccurate titrations, or to over or under estimation of the volume changes, are all thrown on the final result, of which they may form a considerable part. We have consequently altogether discarded the use of baryta as an absorbent in favour of caustic soda. The carbonate is esti- SEPTEMBER 14. 1899] WA TURE 479 mated by a double titration process, suggested a few years ago by Hart, and we have succeeded in so far improving this method that there is no difficulty in determining in 100 c.c. of the alkaline solution an amount of carbonate corresponding to ;'5 c.c. of carbon dioxide. There is practically no limit to the amount of air which can be passed through an absorbing apparatus such as I have de- scribed, and one of very moderate dimensions will allow from 100 to 150 litres per hour to pass with perfect safety. Larger amounts can be dealt with either by increasing the size of the apparatus or by using several smaller ones arranged in parallel. With proper precautions, determinations can certainly be made to within ‘02 part of carbon dioxide in 10,coo of air, so that with an apparatus of this kind it is possible to estimate the intake of carbon dioxide into a leaf or plant from ordinary atmospheric air, and to keep a sufficiently rapid stream of air passing over the leaf to maintain the tension of the carbon dioxide only slightly below the normal amount. The air is measured by carefully standardised meters, reading to about 20 c.c. ; and since the amounts of air aspirated vary from 100 to goo litres or more, there are practically no errors of measurement. The tension at which the air passes through the absorption apparatus is measured by a manometer, and all the volumes are reduced to standard temperature and pressure. All such experiments of course necessitate, not only a deter- mination of the carbon dioxide in the air which has passed over the leaf or plant, but also a simultaneous determination of the carbon dioxide in the ordinary air used. The aecumulation of these air determinations clearly shows that the ordinary state- ments of our text-books as to the amount of carbon dioxide and its limits of variation are altogether misleading. In our experiments the air was in all cases taken froma height of four feet six inches from the ground, the amounts aspirated varying from 100 to 500 litres. In the month of July 1898, the minimum amount of carbon dioxide found was 2°71 parts per 10,000 of air, and the maximum 2°86. During the winter months, when the ground was almost bare of vegetation, it rose to from 3°00 to 3°23 parts per 10,000 ; and on one foggy day, March 16, 1899, after a whole week ot similar weather, we found the very exceptional amount of 3°62. Asa rule, we may take it that the amount of carbon dioxide in the atmosphere during the period of greatest plant growth rarely falls short of 2°7 parts per 10,000, and rarely exceeds 3°0 parts, with an average of about 2°85. These numbers come very close to the determinations of Reiset, and of Miintz and Aubin, and agree also fairly well with the Montsouris deter- minations. If instead of taking the air from a height of three or four feet from the ground, we examine the stratum only one or two centimetres above the surface of a soil free from vegetation, we find, as might be expected, a very large increase in the amount of carbon dioxide, which may exceed, under these circumstances, 12 or 13 parts per 10,000 of air. Such a soil, in fact, gives off by diffusion into the surrounding air an amount of carbon dioxide which is comparable to that evolved by a respiring leaf, that is to say, about 50 c.c. per square metre per hour. This is probably a factor which has to be taken into account in considering the assimilative power of vegetation of very low growing habit, but in all other cases we may assume with safety that aérial plants have to take in their carbon dioxide from air in which its tension does not exceed ;5%y5 of an atmosphere. The actual intake of carbon dioxide is determined by en- closing the entire leaf in specially constructed air-tight, glazed cases, through which a sufficiently rapid air stream is passed. These cases are so arranged that the leaf can be enclosed whilst still attached to a plant which is growing out in the open under perfectly natural conditions, and some of them are sufficiently large to take the entire leaf of a sunflower. The carbon dioxide content of the air is determined both before and after its passage through the apparatus, and since the amount of air passed is known we have all the data requisite for determining the actual amount retained by the leaf. An experiment generally lasts from five to six hours, and the carbon dioxide fixed in this time may amount to 150 c.c. or more, the actual error of determination being very small indeed. For purposes of comparison the volumes are reduced to the NO. 1559, VOL. 60] actual number of cubic centimetres of the gas absorbed by a square metre of leaf in one hour, which of course necessitates an exact determination of the area of the leaf. This is most conveniently effected by printing the leaf on sensitised paper, and tracing round its outline with a planimeter set to read off square centimetres—a far more accurate and expeditious plan than that of cutting out a fac-simile of the leaf from paper of a known weight per unit of area. If it is desired to estimate the assimilative power of a leaf in an atmosphere artificially enriched with carbon dioxide, the air stream before entering the leaf case is passed through a small tower containing fragments of marble, over which there drops a very slow stream of dilute acid, whose rate of flow is so pro- portioned to the air stream as to give about the desired enrich- ment with carbon dioxide. The stream of air is then divided, one part going on directly to the leaf case, whilst the other passes through a separate absorption apparatus and meter for the accurate determination of its carbon dioxide content. In order to show the kind of results obtained in this manner, I will give one or two examples. A leaf of the sunflower, having an area of 617°5 sq. cm., was enclosed in its case whilst still attached to the plant, and was exposed to the strong diffuse light of a clouded sky for five and a half hours, air being passed over it at the rate of nearly 150 litres per hour. The content of the air in carbon dioxide as it en- tered the apparatus was 2°80 parts p2r 10,000, and this was reduced to 1°74 parts per 10,000 during its passage over the leaf. This corresponds to a total absorption of 139°95 c.c. of carbon dioxide, or to an intake of 412 c.c. per square metre per hour. If we assume that the average composition of the carbo- hydrates formed is that of a C;H,,O, sugar, the above amount of carbon dioxide corresponds to the formation of 0 55 gram of carbohydrate per square metre per hour. But we must bear in mind that the average tension of the carbon dioxide in the leat case was only equal to 1°93 parts per 10,000—that is, only about seven-tenths of its tension in the normal air. A cor- rection has therefore to be made if we wish to know how much the leaf would have taken in, under similar conditions of insola- tion, if it had been bathed with a current of air of sufficient rapidity to practically keep the amount of carbon dioxide constant at its normal amount of 2°8 per 10,000. We shall see later on that, well within the limits of this experiment, the intake is pro- portional to the tension, so that applying this correction we may conclude that under identical conditions of insolation and temperature this leaf would have taken in an amount of carbon dioxide from the free air at a rate sufficient to produce o°8 gram of carbohydrate per square metre per hour. This is almost exactly equal to the assimilation rate of the sunflower which I deduced in 1892 from the indirect process of weighing equal areas of the leaf lamina before and after insolation, and it also agrees fairly well with some of Sachs’ original experiments of a similar nature. In another experiment made with the leaf of Catalpa big- nonzozdes in full sunlight, the amount of carbon dioxide in the air passing over the leaf fell from 2°80 to 1°79 parts per 10,000, the total hourly intake for the square metre being 344°8 c.c. When this is corrected for tension, it corresponds to an assimil- ation in free air of 0°55 gram of carbohydrate per square metre per hour. An increase in the intensity of the daylight, as might be expected, influences to some extent the rate of intake of atmo- spheric carbon dioxide; but providing the illumination has reached a certain minimum amount, a further increase in the radiant energy incident on the leaf does not result in anything like a proportional amount of assimilation. We have found, for instance, that the rate of assimilation of a sunflower leaf, exposed to the clear northern sky on a warm summer's day, was about one-half of what it was when the leaf was turned round so as to receive the direct rays of the sun almost normal to its surface. Now in this latter case the actual radiant energy received by the leaf was at least twelve times greater than was received from the northern sky, but the assimilation was only doubled. These differences in the effect of great variation of illumin- ation become stil less marked when we use air which has been artificially enriched with carbon dioxide. In one instance of this kind, for example, we found the assimilation in the full diffuse light of the northern sky to be 87 per cent. of what it was in direct sunshine. This brings me to another interesting point on which I have 480 NAT ORE [SEPTEMBER 14, 1899 already touched slightly—the enormous influence which slight changes in the carbon dioxide content of the air exert on the rate of its ingress into the assimilating leaf. With a constant illumination, either in direct sunlight or diffuse light, the assimilatory process responds to the least variation in the carbon dioxide, and within certain limits, not yet clearly defined, the intake of that gas into the leaf follows the same rule as the one which holds good with regard to the absorption of carbon dioxide by a freely exposed surface of a solution of caustic alkali; that is to say, from air containing small but variable quantities of carbon dioxide ¢he entake 2s directly proportional to the tension of that gas. A single experiment will be sufficient to illustrate this. A large sunflower leaf, still attached to the plant and exposed to a clear northern sky, gave an assimilation rate equal to 0°331 gram of carbohydrate per square metre per hour, when air was passed containing anaverage amount of 2°22 parts of carbon dioxide per 10,000. When the experiment was repeated under similar conditions of illumination, but with air containing 14°82 parts of CO, per 10,000, the intake corresponded to an hourly formation of 2°409 grams of carbohydrate per square metre. The ratio of the tensions of the carbon dioxide in the two experiments is I to 6°7, and the assimilatory ratio is I to 72, so that the increased assimilation is practically proportional to the increase in tension of the carbon dioxide. Since an increase of carbon dioxide in the atmosphere sur- rounding a leaf is followed by increased assimilation even in diffuse daylight, it is clear that, under all ordinary conditions of illumination, the rays of the right degree of refrangibility for producing decomposition of carbon dioxide are largely in excess of the power of the leaf to utilise them. Under natural con- ditions this excess of radiant energy of the right wave-length must, from the point of view of the assimilatory process, be wasted, owing to the limitation imposed by the high degree of dilution of atmospheric carbon dioxide. But although the actual manufacture of new material within the leaf lamina is so largely influenced by small variations in the carbon dioxide of the air, we are not justified in concluding that the plant as a whole will necessarily respond to such changes in atmospheric environment, since the complex physiological changes involved in metabolism and growth may have become so intimately cor- related that the perfect working of the mechanism of the entire plant may now only be possible in an atmosphere containing about three parts of carbon dioxide in 10,000, We have commenced a series of experiments which will, I hope, throw considerable light on this point, but the work is not at present in a sufficiently advanced state for me to make more than a passing allusion to it. The penetration of the highly diluted carbon dioxide of the atmosphere into the interior air-spaces of the leaf on its way to the active centres of assimilation must, in the first instance, be a purely physical process, and no explanation of this can be accepted which does not conform to the physical properties of the gases involved. Since there is no mechanism in the leaf capable of producing an ebb and flow of gases within the air spaces of the mesophyll in any way comparable with the movements of the tidal air in the lungs of animals; and since also the arrangement of the stomatic openings is such as to effect a rapid equalisation of pressure within and without the leaf, we must search for the cause of the gaseous exchange, not in any mass movement, but in some form of diffusion. This may take place in the form of open diffusion through the minute stomatic apertures, which are in communication both with the outer air and the intercellular spaces, or the gaseous exchange may take place through the cuticle and epidermis by a process of gaseous osmosés, similar to that which Graham investigated in connection with certain colloid septa. For many years there has been much controversy as to which form of gaseous diffusion is the more active in producing the natural interchanges of gases in the leaf. The present occasion is not one in which full justice can be done to the large amount of experimental work which has from time to time been carried out in this direction. Up to comparatively recently the theory of cuticular osmosis has been the one which has been more com- monly accepted, free diffusion through the open stomata being considered quite subsidiary. In 1895, however, Wir: eae Blackman brought forward two remarkable papers which opened up an entirely new aspect of the subject. After showing the NO. 1559, VOL. 60] fallacy underlying certain experiments of Boussingault, which had been generally supposed to prove the osmotic theory of exchange, Mr. Blackman gave the results of his own experiments with a new and beautifulty constructed apparatus, which enabled him to measure very minute quantities of carbon dioxide given off from small areas of the upper and under sides of a re- spiring leaf, and also to determine the relative intake of carbon dioxide by the two surfaces during assimilation in air artificially charged with that gas. The conclusions drawn are that respira- tory egress, and assimilatory ingress of carbon dioxide, do not occur in the upper side of a leafif this is devoid of stomatic openings, and that when these openings exist on both the upper and under sides the gaseous exchanges of both physiological pro- cesses are directly proportional to the number of stomata on equal areas, hence in all probability the exchanges take place only through the stomata.! These observations of Mr. Blackman are of such far-reaching importance, and lead, as we shall see presently, to such remark- able conclusions with regard to the rate of diffusion of atmo- spheric carbon dioxide, that we felt constrained to inquire into the matter further, and for this purpose we employed a modified form of the apparatus which we have used throughout our work on as- similation. This was so arranged that a current of ordinary air could be passed, just as in Mr. Blackman’s experiments, over the upper and lower surface of a leaf separately, the increase or decrease in the carbon dioxide content of the air being de- termined by absorption and titration in the manner I have already alluded to. In this way we were able to employ comparatively large leaf areas, and to continue an experiment for several hours, so that we had relatively large amounts of carbon dioxide to deal with, and the ratios of gaseous exchange of the two sides of the leaf could consequently be determined with considerable accuracy. Our results, on the whole, are decidedly confirmatory of Mr. Blackman’s observations. The side of a leaf which is devoid of stomatic openings certainly neither allows any carbon dioxide to escape during respiration, nor does it permit the ingress of that gas when the conditions are favourable for assimilation, On the other hand, when stomata exists on both the upper and under sides of a leaf, gaseous exchanges take place through both surfaces, and, as a rule, in some sort of rough proportion to the distribution of the openings. There is, however, under strong illumination, a greater intake of carbon dioxide through the upper surface than would be expected from a mere con- sideration of the ratio of distribution of the stomata.? Never- theless, the general connection between gaseous exchange and distribution of stomata is so well brought out that we must regard it as highly probable that these minute openings are the ae paths by which the carbon dioxide enters and leaves the leaf. We must now look at certain physical consequences which proceed from this assumption, and see how far they can be justified by the known or ascertainable properties of carbon dioxide at very low tensions, The leaf of Catalpa bignondotdes is hypostomatic, and there- fore takes in carbon dioxide only by its lower surface. Under 1 There is one important fact to be borne in mind when considering how far these observations exclude the possibility of cuticular osmosis. In the many leaves we have examined, Mr. Escombe and I have found that the occurrence of stomata on the upper surface of the leaf is always correlated with a much less dense palisade parenchyma. The cuticle and epidermis under these conditions are in a much more favourable state to allow carbon dioxide to pass into the leaf by osmosis than when the closely-packed palisade «cells abut against the epidermis, as they do when this is 1m- perforate. 2 Granted that the stomata constitute the paths of gaseous exchange, it is clear that the amount of diffusion through them, other things being equal, must depend very largely on the extent to which they are opened. The delicate self-regulating apparatus which governs the size of the open- ings is so readily influenced, amongst other things, by differences of illumination, that a2 /7or2 we should not expect the stomata on the upper surface of an insolated leaf to be in the same condition as those of the more shaded lower surface. This may very well account for the stomatic ratio of the two sides not being in closer correspondence with the assimilatory ratios, as found in most of our experiments carried out in bright sunlight. In light of lesser intensity there is always a closer correspondence of the two ratios. There is also another possible explanation of the fact. Since we have good reason to believe that the principal part of the assimilatory work is carried on by the palisade parenchyma, which occurs in the upper side of the leaf, the tension of the carbon dioxide in the air spaces of that part of the mesophyll is probably less than it isin the spongy parenchyma. There will, therefore, be a higher ‘‘diffusion gradient” between the carbon dioxide of the outer and inner air in the former case than in the latter, and this would certainly tend toa more rapid diffusion through the openings in the upper side of the leaf. Ps SEPTEMBER 14, 1899] NATURE 481 favourable conditions it is quite possible, during assimilation, to | obtain an intake of atmospheric carbon dioxide into this leaf | at the rate of 700 c.c. per square metre per hour (measured at | o” and 760 mm.), corresponding to an average linear velocity of the carbon dioxide molecules of 3°8 centimetres per minute, supposing the intake to be distributed evenly over the whole | of the lower leaf surface. This velocity is almost exactly one- half of that at which carbon dioxide will enter a freely exposed surface of a solution of caustic alkali, But if the intake of the gas is confined to the stomatic openings of the leaf, its velocity of ingress must be very much greater than this. We have carefully determined the number of stomata occurring on a given area of this particular leaf, and also the dimensions of | ard ai When a shallow vessel containing a solution of caustic alkali is completely covered, the air above the liquid is very speedily deprived of the whole of its carbon dioxide. If we now imagine a hole to be made in the cover of the vessel, carbon dioxide will enter the air space by free diffusion, and its amount can be very accurately determined by subsequent titration in the manner I have previously referred to. The time occupied by the experi- ment and the dimensions of the aperture being known, we can express the results in actual amounts of carbon dioxide passing through unit area of aperture in unit of time; or, since the | tension of that gas in the outer air is known, we can express the average rate of the carbon dioxide molecules across the aperture in terms of actual measurement, say centimetres per minute. We have made a very large number of experiments of this kind, using, in the first instance, dishes of about 9 cm. in diameter, and varying the size of the holes in the cover, the air space over the absorbent liquid being always the same. The accompanying curve, Fig. 1, illus- trates the effect which a gradually de- creasing orifice has on the rate of diffusion of atmospheric carbon dioxide under these conditions. The diameters of the orifice in millimetres are given on the abscissa i s line, and the rates of diffusion through equal areas of the apertures are taken as ordinates, the rate of absorption in the open dish under similar conditions being 40 45 SO 55 60 65 70 Fic. 1. the openings, and find that the total area of the openings, sup- posing them to be dilated to the fullest possible extent, amounts to just under one fer cent. of the leaf surface. It follows from this that the average velocity of the atmospheric carbon dioxide in passing through these openings must be 380 centzmetres per minute, that is to say, just 7/¢y times greater than into a freely exposed absorbent surface of alkali. In other words, supposing every one of the stomatic openings of this leafcould be filled up with a solution of caustic alkali, the absorbent power of the leaf as a whole would only be =}; of what it actually is when assimi- lating. These are some of the consequences which flow from an acceptance of the hypothesis of stomatic exchange, and it appeared to be impossible to accept that hypothesis unreservedly without some collateral evidence that these comparatively high 75 velocities of diffusion are physically possible when dealing with such low gradients of tension as must necessarily exist when the highest amount of carbon dioxide does not exceed ‘03 per cent. The well-known general law expressing the rate of the spontaneous intermixture of two gases when there is no inter- vening septum was, as every one knows, established by Graham, and the more elaborate investigations of Loschmidt many years later served to confirm the general accuracy of this law, and to show that, within very narrow limits, the diffusion constant varies in different gases inversely as the square roots of their densities. But a mere knowledge of the diffusion constants of air and carbon dioxide does not, as far as I can see, materially assist us in the particular case we have under consideration. In order to gain some idea of what is actually possible in the way of stomatic diffusion in an assimilating leaf, we must know some- thing of the actual rate at which atmospheric carbon dioxide can be made to pass into a small chamber containing air at the outside tension, but in which the carbon dioxide is kept down almost to the vanishing point by some rapid process of absorp- tion ; and we must also determine the influence of varying the size of the aperture through which the diffusion takes place. Our attempts to answer these questions experimentally have led us into a long investigation, which promises to be of wider interest than we had first imagined. I only propose to give on this occasion a general account of the results so far as they affect the physical question of the intake of carbon dioxide into the plant. NO. 1559, VOL. 60] taken as unity. It will be seen that in the first instance a gradual reduction of the diameter of the opening is accompanied by a very regular increase in the rate of passage of the carbon dioxide until a diameter of about 50 mm. is reached ; that is to say, up toa point at which about two-thirds of the area of the dish is covered. A further progressive diminution in the size of the aperture makes comparatively little difference in the diffusion rate until we reach about 20 mm., beyond which the curve again begins to rise, increasing rapidly in steepness as the apertures become smaller. The experiments with open dishes are too crude for a study of the influence of very small apertures, so for this part of our work we constructed a special form of apparatus which has enabled us to determine the relative rates of diffusion through orifices in thin metal plates ranging down to I mm. in diameter. 16 18 20 22. 2422M, /é Fic. 2. I have plotted the results of such a series of experiments (see Fig. 2), showing the relative rates of diffusion of atmospheric carbon dioxide through equal areas of apertures between 20 mm. and I mm. in diameter, under constant conditions, and it will be noticed how very steep the curve becomes after diameters of 5 or 6 mm. are reached. The speed at which the diffusion of atmospheric carbon dioxide takes place through unit area of an orifice of I mm. in diameter is just sixteen times as fast as it is through unit area of an aperture of 20 mm. ; and since we know that the rate of passage in the latter case is two and a half times greater than 482 the absorption rate of an equal area of a freely exposed surface of a solution of caustic alkali, we arrive at the conclusion that, under the particular conditions of our experiment, the diffusion rate through an aperture of I mm. is forty ¢imes greater than the rate of absorption of a free alkaline surface of equal area. This corresponds to an actual average rate of passage of the molecules of the atmospheric carbon dioxide of about 266 centi- metres per minute. Now, we have already seen, in the case of a Catalpa leaf, that if the gaseous exchange during assimilation goes on only through the stomatic openings, we require a minimum velocity of something like 380 centimetres per minute, a velocity which we are sensibly approaching in our experiments with apertures of about I mm. in diameter. But the effective area of a stomatic opening of the Catalpa leaf is equal to that of a circle witha diameter of less than 1/100 mm., and since our experiments in- dicate a very rapid increase in the velocity of diffusion as the aperture is diminished, it is clear that no difficulty, as regards the physics of the question, can be raised against the idea that atmospheric carbon dioxide reaches the active centres of assimilation by a process of free diffusion through the leaf stomata. One of the most interesting problems connected with plant assimilation relates to the efficiency of a green leaf as an absorber and transformer of the radiant energy incident upon it. It is already well known that the actual amount of energy stored up in the products of assimilation bears a very small proportion to the total amount reaching the leaf: in other words, the leaf, regarded from a thermo-dynamic point of view, is a machine with a very low ‘‘ economic coefficient.” We » Fic. 3. require, however, to know much more than this, and to as- | certain, amongst other things, how the efficiency of the machine | varies under different conditions of insolation, and in atmospheres containing varying amounts of carbon dioxide. The measure of the two principal forms of work done within | the leaf, the vaporisation of the transpiration water on the one | hand, and the reduction of carbon dioxide and water to the form of carbohydrates on the other, can be ascertained by modifying our experiments in such a manner as to allow the | transpiration water to be determined, as well as the intake of carbon dioxide. For the actual measurement of the total energy incident on the leaf under various conditions we are now using one of Prof. -Callendar’s recording radiometers of specially delicate con- | struction, which will be ultimately calibrated in calories, This instrument gives promise of excellent results, but up to the | present time the work we have done with it is not sufficiently advanced for me to describe. We may, however, obtain a very | fair idea of the variation in the efficiency of a leaf from one or | two examples in which the amount of incident energy was deduced from other considerations. In the case of a sunflower leaf exposed to the strong sunlight of a brilliant day in August, the average amount of radiant energy falling on the leaf during the five hours occupied by the | experiment was estimated at 600,000 calories per square metre | per hour. The averege hourly transpiration of water during | that time was at the rate of 275 cc. per square metre, and the assimilated carbohydrate, estimated by the intake of carbon dioxide, was at the rate of 08 gram per square metre per hour. The vaporisation of 275 c.c. of water must have required the | expenditure of 166,800 calories, and the endothermic pro- duction of o°8 gram of carbohydrate (taking the heat of | NO. 1559, VOL. 60] NALTORE “1 09 190 WO 120 130 140 150 160 170 180 190 200 210 220 229 240 250 260 270 280 | weighs about 250 grams, and its specific heat is about o’9. [SEPTEMBER 14, 1899 combustion at 4000 gram calories) corresponds to the absorp- tion of 3200 calories. Thus, as the final result under these particular conditions of experiment, we find that the leaf has absorbed and converted into internal work about 28 per cent. of the total radiant energy incident on it, 27°5 per cent. being used up in the vaporisation of water, and only one-half per cent, in the actual work of assimilation. In strong diffuse light, such as that from a northern sky ona clear summer’s day, the leaf has a higher ‘‘economic co- efficient,” using that term in relation to the permanent storage of energy in the assimilatory products. In one instance of this kind in which the total energy received by the leaf was approximately 60,000 calories per square metre per hour, it was found that 96 c.c. of water were evaporated and ."41 gram of carbohydrate was formed for the same area and time. This indicates an absorption and utilisation by the leaf of something like 95 per cent. of the incident energy, of which 2°7 per cent has been made use of for actual work of assimilation as against 0°5 per cent. in brilliant sunshine. ! From what I have said previously about the effect of increased tension of carbon dioxide on the rate of assimilation, it must follow that the ‘‘ efficiency ” of a leaf as regards the permanent storage of energy must, caeter?s parzbus, be increased when small additions of that gas are made to the surrounding air. In one such instance, in which the air had been enriched with carbon dioxide to the extent of about five-and-a-half times the normal amount, it was estimated that the ‘efficiency ” of the leaf for bright sunshine was raised from 0'5 to 20 per cent. Up to the present we have been regarding the efficiency of the assimilatory mechanism of a plant in reference to the /ofa/ energy of all grades which falls upon the leaf. It is, of course, well known that the power of decomposing carbon dioxide is limited to rays of a certain refran- gibility, and the researches of Timi- riazeff, Engelmann and others leave little room to doubt that the rays of the spectrum which are instru- mental in producing the reaction in the chloroplastids have a distinct relation to the absorption bands of the leaf-chlorophyll. By far the greater amount of the assimilatory work, probably more than 90 per cent. of it, is effected by the rays which correspond to the principal absorption band in the red, lying between wave-lengths 6500 and 6975." If, therefore, we express the distribution of energy in a normal solar spectrum in the form of a curve, we have the means of approximately deter- mining the maxzmum theoretical efficiency of a green leaf, that is to say, the maximum amount of assimilatory work which could be produced, supposing the conditions so favourable as to admit of the whole of the energy corresponding to this absorption band being stored up within the leaf. It is not without interest to get an approximate idea of this theoretical maximum. For this purpose I have here reproduced a curve given by Prof. S. P. Langley representing the distribution of energy at the sea-level in the normal spectrum of a vertical sun shining in 1 The principal factor which determines the amount of transpiration in a plant must be the amount of radiation falling on it. It is essential that the water-bearing mechanism should be able to keep up a goud supply of water to the leaf lamina in order to prevent the temperature rising to a danger- ously high point. This ‘‘ safety valve” function of the transpiration cur- rent is not always sufficiently borne in mind, and we are too apt to think that the plant requires these enormous amounts of water in order to supply itself with the requisite mineral salts. The absolute necessity for the supply as a dissipator of energy willjbecome evident by taking one or two facts into consideration. A square metre of the lamina of the leaf of a sunflower We have seen that the hourly transpiration in bright sunshine may be as much as 275 c.c. per square metre, requiring the expenditure of 162,800 calories, and it therefore follows that, if the loss of water were stopped, the temperature of the leaf would rise at the rate of more than 12° C. fer minute. In making our experiments in glazed cases it has sometimes been very interesting to watch the result of any accidental stoppage of the water-current in the leaf- stalk, and the almost instantaneous effect this has in destroying the leaf when the insolation is of high intensity. 2 These limits are those of the band as measured by passing sunlight through the leaf itself. In an alcoholic solution of chlorophyll the band lies between A 6400 and A 6850. I must here express my thanks to Mr. Charles A. Schunck for having kindly undertaken to make these measure- ments for me. SEPTEMBER 14, 1899] aclear sky. The total amount of incident energy represented by the whole area of the curve is 1°7 calories per square centimetre per minute, or 1,020,000 calories per square metre per hour. I have drawn a thick black vertical band in the red end of the spectrum corresponding in position and breadth with the principal absorption band of chlorophyll as seen in a green leaf. By integration it may be shown that the area of this part of the curve is about 6°5 per cent. of that of the whole curve, so that this value represents something like the theoretical maximum efficiency of a leaf in bright vertical sunshine, supposing the conditions could be made so favourable as to result in a com- plete filtering-out and utilisation of the whole of the rays of the right period for producing decomposition otf carbon dioxide. This maximum efficiency expressed in calories per square metre per hour is 66,300, corresponding to the heat of formation of about 16°5 grams of carbohydrate. Under the most favour- able conditions we have employed up to the present we have not obtained a larger production than about 3°0 grams of carbo- hydrate per square metre per hour, or about 18 per cent. of the theoretical maximum ; but this was in air containing only 16°4 parts of carbon dioxide per 10,000, which must be very far below the true optimum amount. The brilliant discoveries of recent years on the constitution and synthesis of the carbohydrates have not brought us sensibly nearer to an explanation of the first processes of the reduction of carbon dioxide in the living plant. The hypothesis of Baeyer still occupies the position it did when it was first put forward nearly thirty years ago, although it has, it is true, received a certain amount of support from the observations of Bokorny, who found that formaldehyde can, under certain conditions, contribute to the building up of carbohydrates in the chloro- lasts. 3 The changes which go on in the living cell are so rapid, and are of such a complex kind, that there seems little or no hope of ascertaining the nature of the first steps in the process unless we can artificially induce them under much simpler conditions. The analogy which exists between the action of chlorophyll in the living plant and that of a chromatic sensétiser in a photo- graphic plate, was, I believe, first pointed out by Captain Abney, and was more fully elaborated by Timiriazeff, who was inclined to regard chlorophyll as the sensitiser par excellence, since it absorbs and utilises for the assimilatory process the radi- ations corresponding approximately to the point of maximum energy in the normal spectrum. The view which Timiriazeff has put forward, that there is a mere physical transference of vibrations of the right period from the absorbing chlorophyll to the reacting carbon dioxide and water, is, I think, far too simple an explanation of the facts. Chromatic sensitisers have been shown to act by reason of their antecedent decomposition and not by direct transference of energy, and the same probably holds good with regard to chlorophyll, which is also decomposed by the rays which it absorbs. We must probably seek for the first and simplest stages of the assimilatory process in the inter- action of the reduced constituents of the chlorophyll and the elements of carbon dioxide and water, the combinations so formed being again split up in another direction by access of energy from without. The failure of all attempts to produce such a reaction under artificial conditions is, I think, to be accounted for by the neglect of one very important factor. We are dealing with a reaction of a highly endothermic nature, which is probably also highly veverszb/e, and on this account we cannot expect any | : | secretaries, sensible accumulation of the products of change unless we employ some means for removing them from the sphere of action as fast as they are formed. In the plant this removal is provided for by the living elements of the cell, by the chloroplast, assisted no doubt by the whole of the cytoplasm. We have here, in fact, the analogue of the chemical sensitisers of a photographic plate, which act as halogen absorbers, and so permit a sensible accumulation of effect on the silver salts. When we have succeeded in finding some simple chemical means of fixing the initial products of the reduction of carbon dioxide, then, and then only, may we hopefully look forward to reproducing in the laboratory the first stages of the great synthetic process of nature on which the continuance of all life depends, NO. 1559, VOL. 60] NATURE 483 NOTES. THE Allahabad Proncer Maz? understands that Mr. J. N. Tata, of Bombay, has determined to dissociate his offered endowment for a scientific research institute in India from the proposed family settlement, which was one of the original con- ditions, as the latter part of the scheme presented insuperable difficulties. With great generosity and public spirit Mr. Tata has declared his intention of making his offer, which amounts, it will be remembered, to some thirty lakhs of property, quite unconditional. He is now preparing, in consultation with the provisional committee, a revised scheme for submission to Government. In preparing it, he and the provisional committee will utilise all the information and advice they have received from all parts of India in response to the circulars issued some months ago, and there is good prospect of a practical plan being evolved. THE forty-eighth annual meeting of the American Associ- ation for the Advancement of Science was held at Columbus, Ohio, on August 19-26, under the presidency of Dr. Edward Orton, of Ohio State University. There were 350 members and associates present, and 273 papers were communicated to: the sections. The address of the retiring president, Prof, F. W. Putnam, of Harvard University, was published in last week’s NaTuRE, and portions of the addresses delivered by presidents of the sections will appear at the earliest opportunity. The subjects of these addresses are :—Section of Mathematics and Astronomy, ‘‘The Fundamental Principles of Algebra,” by Prof. A. Macfarlane; Section of Mechanical Science and Engineering, ‘‘ Engineering Education as a Preliminary Train- ing for Scientific ,Research Work,” by Prof. Storm Bull ; Section of Zoology, ‘‘The Importance and the Promise in the Study of the Domestic Animals,” by Prof. Gage; Section of Geology and Geography, ‘‘The Devonian in Canada,” by Mr. J. F. Whiteaves; Section of Physics, ‘‘The Field of Experimental Research,” by Dr. Elihu Thomson; Section of Chemistry, ‘‘ Definition of the Element,” by Prof. F. P. Venable ; Section of Botany, ‘‘ The Progress and Problems of Plant Physi- ology,” by Prof. Barnes ; Section of Anthropology, ‘‘ Begin- nings of the Science of Prehistoric Anthropology,” by Prof. Wilson. Prof. C. E. Munroe delivered a popular lecture on “© Applications of Modern Electricity.” New York was selected as the place of meeting next year, and Prof. R. S. Woodward, Columbia University, was nominated president. A VERY successful congress of mining engineers was held at Teplitz, in Bohemia, on September 4-8. It was attended by 400 mining engineers from all parts of Austria and by a few representatives of other countries, Great Britain being repre- sented by Mr. H. Bauerman, Mr. Bennett Brough and Mr, D. A. Louis. Mr. Gottfried Hiittemann, of Briix, was elected president; Mr. J. Gleich, of Klagenfurt, and Prof. Clemens | Winkler, of Freiberg, vice-presidents ; and Prof. J. von Ehren- werth, of the Przibram School of Mines, and Mr. M. Heinsius, Papers were read by Prof. Clemens Winkler, on the history of combustion with reference to the duration of the world’s coal supply ; by Prof. Otto Frankl, of Prague, on sug- gested reforms in mining law; by Mr. H. Locker, of Briix, on water-inbursts in the Diix-Ossegg collieries and their influence on the Teplitz hot-springs; and by Mr. A. Bloemendal, of Vienna, on the electric transmission of power in mines. It was decided that the next mining congress should be held in Vienna in four years’ time. In connection with the congress, excursions were arranged to the brown coal mines of the Briix Coal Co. and of the Bruch Coal Co., to the Teplitz rolling mills, to the Aussig chemical works, to Edmundsklamm and other points of geological interest in the Bohemian Switzerland, and to the 484 NATURE [SEPTEMBER 14, 1899 Kladno collieries. The importance of the brown coal mines of the Teplitz district is shown by the fact that last year they pro- duced no less than 15,044,563 tons, and afforded employment to 25,212 workmen. Tue reports which the 7z#es correspondent at St. Johns has received from the members of the Peary Polar expedition, who have returned in the steamer Windward, are disappointing. Grinnell Land was explored to its western extremity last autumn; the north remains to be explored. Next spring, Lieut. Peary will undertake the three years’ further prosecution of his quest for the pole, Captain Sverdrup, in the Fram, wintered fifty miles south of the Wnxdward, in latitude 79°. The work of the expedition has so far been unimportant. Tue Danish Greenland expedition, under Lieut. Amstrup, has returned to Mandal, after a year’s absence, and reports that no trace was found of Herr Andrée and his companions. A Reuter telegram states that the Swedish search expedition under Dr. Nathorst, which has just arrived at Malmo, brings af€similar report. The expedition explored Kaiser Franz joseph Fiord, on the east coast of Greenland, and there discovered a whole series of new inlets, the position of which was mapped. An especially interesting ethnographical collection relating to the now extinct Eskimo population was secured in that region. THE forty-fourth annual exhibition of the Royal Photographic Society, which will he held at the Gallery of the Royal Society of Painters in Water Colours, is now in course of preparation, and will be opened to the public on Monday, September 25, On Saturday, the 23rd, there will be a private view for members, exhibitors, and their friends, and in the evening there will be a conversazione, when the President, the Earl of Crawford, K.T., will receive the members and the other guests of the Society. for a period of seven weeks. A CONGRESS of the Royal Institute of Public Health will be held at Blackpool on September 21-28. A GouRSE of twelve free lectures on the ‘‘ Pleistocene Mam- malia” will be delivered by Dr. R. H. Traquair, F,R.S., in the Lecture Theatre of the Museum of Practical Geology, Jermyn Street, S.W., on Mondays, Wednesdays and Fridays, at 5 p-m., beginning Monday, October 2, and ending Friday, October 27. THE committee appointed by the American Chemical Society to consider the means by which the Society could hasten the adoption of uniform systems of graduation, definite limits of accuracy, and standard methods for using all forms of measuring instruments employed in chemical laboratories have, we learn from Sczence, made the following recommendations :—(1) That the American Chemical Society, in a manner consistent with its constitution and bye-laws, ask the U.S. Office of Weights and Measures to adopt regulations for the verification of volumetric apparatus which shall be similar in purpose and scope to the regulations of the Kaiserliche Normal-Aichungs-Commission, after due consideration of the criticisms to which the latter have (2) That the U.S. Office of Weights and Measures be asked to give special consideration to the question of a standard temperature or temperatures to be adopted for the graduation of volumetric apparatus, and to obtain as far as prac- ticable an expression of opinion from American chemists on this (3) That the U.S. Office of Weights and Measures be to submit its regulations to the American Chemical Society, or a duly appointed committee thereof, for suggestions before final adoption by that office. (4) That the international (5) That the litre been subjected. point. asked kilogram be adopted as the standard mass. NO. 1559, VOL. 60] as defined by the International Committee on Weights and Measures be adopted; viz. the volume of the mass of a kilo- gram of pure water at the temperature of maximum density and under a pressure of 760 mm, of mercury. (6) That all density determinations be referred to water at its maximum density and under a pressure of 760 mm, of mercury. (7) That all temper- atures be expressed in terms of the hydrogen thermometer of the International Bureau of Weights and Measures. (8) That ifany question arise as to the interpretation of the above definitions the decision and standards of the U.S. Office of Standard Weights and Measures shall be accepted by the Society as final. Tue Rev. J. M. Bacon contributes to Good Words a general account of his experiments on the audibility of sound in air. It is well known that the report of the explosion of a large meteor may be heard over a great area, although the air at the point where the explosion occurs must be extremely attenuated. Mr. Bacon has endeavoured to imitate the meteoritic explosions to some extent by electrically firing Tonite cartridges suspended below a balloon. An ascent was made, and cartridges were fired at intervals, the altitude of the balloon ranging from 2000 to 3000 feet. The reports were heard by many observers in the parts of London over which the balloon passed, and some in- teresting conclusions were derived from these observations. In the balloon itself careful readings were taken of the interval of the return of the echo from the earth, and the height the balloon had ascended, while the actual locality over which each cartridge was fired was also noted. From the results obtained, it ap- peared that there were no aérial echoes, as in Prof. Tyndall’s experiments, and that in all cases the reports in their double journey did not travel as quickly as the estimated speed of sound on the earth. ‘*In consequence of these unexpected re- cords,” says Mr. Bacon, ‘‘ another ascent was carried out shortly afterwards from the Crystal Palace when the air was in a totally different condition, and the altitude reached considerably higher. On that day a strange thing happened. The afternoon was an universal drizzle, and the Palace towers had their heads nearly shrouded in the low-lying clouds. On rising the balloon at once made for the west, and entering the cloud shortly re- appeared above in glorious sunshine. So for nearly two hours, when, once again descending through the clouds, we found ourselves still going west, but dead over the middle of the river below the fort at Gravesend! All unsuspected by the voyagers, a wind was blowing above the cloud-layer diametrically opposite to that on earth, but causing no impediment to sound thereby. The actual results obtained on the last occasion entirely con- firmed those of the former experiment, and differed only in the fact that the reports were apparently heard over a much larger range of country, extending well into the neighbouring counties, and that the reverberations following them, as heard from above, were yet more prolonged than before, sometimes indeed still lingering on after an interval of thirty seconds.” THE Danish Meteorological Office has just published a valu- able excerpt paper from its Aarbog, giving the meteorological means and extremes for the Faroe, Iceland and Greenland. At Thorshavn (Faroe) the mean monthly values of air temperature during twenty-five years vary from 37°°8 in January and March to 51°74 in July. The absolute maximum was 70°'2, and the minimum 11°*r. The mean annual rainfall was 63°3 inches, and the greatest fall in twenty-four hours 2°5 inches. For Iceland mean temperature values are given for nineteen years at fifteen stations ; the lowest yearly mean is 30°°6 at Moedrudal, and the highest, 41°°o at Vestmannoe, At Stykkisholm the absolute maximum during twenty-two years was 73°°2 in July, and the minimum — 14°°8 in January. The meanannual rainfall was 24°9 inches, and the greatest fall in twenty-four hours 2'04 inches. For Greenland four stations are given; at the most northern SEPTEMBER 14, 1899] station, Upernivik, latitude 72°°47, longitude 55°53 W., the mean temperature of twenty-one years was 16°°2, absolute maximum 64°‘0, minimum — 41°'1. The average rainfall was only 8-9 inches, and the greatest fall in twenty-four hours 2°08 inches. Tue report of the president of the American Museum of Natural History, on the work done during 1898, is a very satis- factory statement of scientific progress, especially the parts of it referring to archeological work and explorations made in con- nection with the museum. The institution now offers to the student of Mexican and Central American archeology unrivalled opportunities for the study of the sculptures and hieroglyphic writings of the ancient peoples of these portions of America. Noteworthy among the numerous explorations referred to in the report is the Jesup North Pacific Expedition. Before the organis- ation of this expedition the archeological work conducted on the north-west coast of America was very limited. During the past two years several field parties have carried on very extensive investigations in connection with the Jesup expedition, and have added very considerably to the collections in the museum. During 1897 the field work of the expedition was confined to the coast of British Columbia. In 1898 the work was taken up on a more_ extended scale. Parties were in the field on the coast of the State of Washington, in the southern interior of British Colum- bia, and on the Amoor River in Siberia. One of the illustrations in the report, showing a rock carving found in Van- couver Island, where the shell-heaps of the early inhabitants are being investigated, is here reproduced. ON July 19, for the fifth time during the present century, the city of Rome was damaged by an earthquake. On this last occasion, however, the injuries to build- ings were of slight importance, the in- tensity of the shock having been greaest at Frascati and Marino. Dr. Baratta, who gives a brief description of the earth- quake in the Godlettino of the Italian Geographical Society, remarks that, in its small meizoseismal area, it resembled the shocks which are characteristic of active and extinct volcanic regions, that it was without doubt of Latian | origin, and one of the more prominent manifestations of seismic activity in the Alban Hills. OnE result of the rapid growth of seismology is the sug- gestion by Dr. Mario Baratta that provision should be made by insurance against the damage to buildings caused by earthquakes in certain countries. He shows that, since the beginning of the seventeenth century, less than forty earth- quakes have been responsible for the deaths of more than 150,000 persons in Italy alone. Moreover, to take but one INCA TO Rae example, the great loss of life during the Ischian earthquake of | 1883 was due to the fact that the buildings had already been damaged by the earthquakes of 1828 and 1881. Dr. Baratta points out some of the conditions that must determine the amount of the premium that should be demanded by insurance The most important is the degree of seismicity of the district ; but this would be modified by others, such as the nature of the surface-rocks, the character of the buildings, &c. One advantage of compulsory insurance against earthquakes in a country like Italy would be that partially damaged buildings NO. 1559, VOL. 60] societies. 485 would be at once rebuilt or repaired, and this would tend to diminish the loss of life in the future. THE Kew Bulletin of Miscellaneous Information, Nos. 152- 153, contains the description of a new parasitic disease of the tea-plant which has made its appearance in Ceylon. The fungus which causes it is described by Mr. G. Massee as Colletots echiene camellie, sp. n. CONSIDERABLY the most gigantic annual plant ever observed is described by Mr. C. H. Baker in the Kew Bulletin. The species in question is dcnzda australis, belonging to the Amar- antaceze, a native of Florida. The branches attain certainly a length of nearly 22, and probably of 25, feet. Hysrips between plants belonging to different genera are so uncommon that any fresh instance deserves a record. The Journal of Botany states that Mr. H. Peirson has found in Kent several examples of an orchid which appears to be a cross betweeen Orchis maculata and Gymnadenta conopsea. A BRIEF summary of the changes which have taken place on Vesuvius from 1872 up to June 1899 is given by Dr. R. V. Matteucci in the Rendéconto of the Naples Academy, vol. 6, 7. Rock carving, Vancouver Island. Mr. A. A. CAMPBELL SWINTON sends us a reprint of his lecture read before the Philosophical Society of Glasgow in March last, on ‘‘ Electric Discharges zz vacuo and the Rontgen Rays.” THE Institution of Chemistry of Great Britain and Ireland has issued, in the form of a handy octavo pamphlet, its regulations for admission to membership, together with a register of fellows, associates and students for the session 1899-1900, and reprints of examination papers set in the session 1898-99. A DETERMINATION of the modulus of elasticity for copper, brass, and steel under small loads by means ofinterference methods is described by Mr. Charles P. Weston in the Physzcal Review vili. 5, and leads to the important conclusion that for copper | and brass, and probably for steel, the ratio between the deflection and a load isa constant quantity for loads ranging from o'5 gr. to those which would give the bar a permanent set. Dr. AGOSTINO. GALDIERI, writing in the Rerdéconto of the Naples Academy, vol. 6, 7, describes a new alga of the family Palmellacez, to which he has given the name Plezurococcus | sudphurartus, and which he has discovered growing round the “fumaroli” or the Solfatara at Pozzuoli. This alga is characterised by its remarkable resistance to heat and to the action of sulphuric acid. Mr. WILLIAM Foster, jun., writes in the Physzcal Review, viii. 5, on the conductivity and dissociation of some electrolytes, and confirms the values of the depressions of the freezing point as determined by Loomis, within as narrow limits as one should expect. The results also, with a few minor exceptions, conform to the dissociation theory as set forth by Arrhenius, and the author considers that in the present state of physical chemistry we are compelled to look upon this theory as the one that most nearly corresponds with the experimental data, thus affording, at least, a working hypothesis by which the most important generalisations can be made. To impress upon students the identity of the laws of force for magnetism and electricity at rest, it is necessary to obtain pictures of electrostatic curves analogous to those shown around magnets by means of iron filings. Mr. David Robertson describes in the Proceedings of the Royal Society of Edinburgh the way in which such dust figures can be produced, and the accompanying illustrations show the kind of results obtained. Electrostatic Dust Figures. A number of materials in the form of powders or short pieces were tried, but the best pictures were given by fine mahogany sawdust. To obtain a picture, a glass plate having one or more pieces of tinfoil stuck upon the under-face, is supported horizon- tally. Sawdust or other suitable material is spread as uniformly as possible over the plate by means of a sieve or muslin bag, and the tinfoil disc or discs are charged by being connected with a Wimshurst machine in action. The plate has to be tapped to assist the arrangement of the particles, and it is necessary to put the machine out of action when the dust begins to move out- wards from the tinfoil. By careful manipulation, distinct indica- tions of the directions of electrostatic lines of force around plane conductors of different shapes, and with like and unlike charges, are produced. The pictures can be fixed by means of a thin layer of paraffin wax on the upper side of the glass plate, or they may be photographed. The two pictures here repro- duced trom Mr. Robertson’s paper show the results obtained with a single disc and with two discs having unlike charges. A MONOGRAPH on “ After-images,”” by Mr. Shepherd Ivory Franz, forms a notable feature of the Psychological Review, iii. 2. This monograph deals, firstly, with an experimental analysis of the conditions affecting the production, the duration, the latent period, the space relations, &c., of the after-image ; and, secondly, with a history of the phenomena and their relation to sensation, to imagination and to memory. The experiments described in the first portion were all made in the psychological laboratory of Columbia University, eleven advanced students being selected as subjects. Regarding the historical aspect, it NO. 1559. VOL. 60] NATORE [SEPTEMBER 14, 1899 would appear that while after-images have formed the subject of numerous writings dating back from Aristotle’s De Somizs, the various theories are far from giving a complete explanation of the phenomena. A FURTHER blow has been dealt to Euler's proof of the Binomial Theorem, by Mr. R. F. Muirhead, writinz in the Proceedings of the Edinburgh Mathematical Society. This time it is not the omission of convergency considerations that is at- tacked, but the generalisation of the relation f(m) f(7z)=/(m+n) by the permanence of equivalent forms. Mr. Muirhead points out that the function /(z}(1— (x) sin 7) +(x) sin wm, where (x), Y(x) are any functions of x, is equal to (1 +.)” when we is a positive integer, and it would be equally valid to infer that functions of this type satisfied the Index Law for all values of m and 7, which is obviously false for most forms of (x) and wp (1). Mr. CHARLES S. SCHLICHTER has published, in the nine- teenth annual report of the United States Geological Survey, Part ii., a theoretical investigation of the motion of ground waters. In it he investigates the laws of motion of water through the interspaces of an agglomeration of equal spheres, and also discusses the general laws of flow of ground waters. In connection with the motion in horizontal planes, the well- known transformations by conjugate functions are applicable ; while the lines of flow in problems relating to the mutual inter- ference of two or more wells are closely analogous to the corresponding lines in two-dimensional hydrodynamical problems involving sourcesand sinks. The applications of known methods of mathematical analysis to the present problem might with advantage be studied to a greater extent than is done at present. A GUIDE to the Collection of Scottish Agates in the Edin- burgh Museum of Science and Art has been prepared by Mr. J. G. Goodchild. The collection was formed by the late Prof. Heddle, whose explanatory notes on the specimens have been incorporated in the descriptions now given by Mr, Goodchild. Dr. HENRY CHARLES LANG, well known as the author of “The Butterflies of Europe,” is bringing out a series of articles in Scrence Gosstp on ‘* Butterflies of the Palzearctic Region.” The article in the September number deals with the genus Papilio, and is illustrated by fine photographs of P. machaon, var. sphyrus, Ub., P. xuthus, L., type and variety xuthulus, Brem., and P. maackiz, Niéu. THE Archives of the Roentgen Ray—the only journal in which the transactions of the Rontgen Society of London are officially reported—has become an indispensable quarterly for all who are interested in the development of radiography, more especially in relation to medicine. The two numbers (vol. iii. No. 4, and vol. iv. No. 1), just received, contain several excellent reproductions of Rontgen-ray photographs, as well as descriptive text referring to them, and notes and articles on recent researches. AN illustrated price list of chemical apparatus has been re- ceived from Messrs. Brewster, Smith, and Co. Instruments and accessories for all branches of experimental and analytical chemistry appear to be included in the catalogue. With the list we have received a description of a simple spring balance— Moore’s Hydrostatic Balance—arranged to illustrate the prin- ciple of Archimedes, and specific gravity. The balance should be of service to teachers of the rudiments of physics. A GLANCE through a catalogue of Rontgen ray apparatus, just issued by the firm of Mr. H. W. Cox, Ltd., shows that the apparatus now available is of a very efficient and compact character. The instruments required to produce successful Rontgen ray pictures are so easily manipulated, and can be ob- tained at so reasonable a price, that there seems no reason why SEPTEMBER 14, 1899] every surgeon should not regard an induction coil and acces- sories as an indispensable part of his general outfit. A note- worthy feature of Mr. Cox’s catalogue is a section in which the principles of construction of induction coils are described, and the best m2thods of using the apparatus explained. Tue Cambridge University Press have issued the following list of additional errata for Lord Kelvin’s ‘‘ Mathematical and Physical Papers,” vol. itl. :—Page 33, line 8, for ‘‘ 21,000,000 ” read ‘ 2,100,000”; p. 68, in heading of Table II., for ‘‘ 289° ” read ‘*288°”; p. 74, line 7, for ‘‘640” read ‘'64”’; p. 173, line 6, for ‘“‘the” (before ‘‘ quantity”) read ‘‘a”; p. 226, value of diffusivity of wood (col. 4) should be ‘‘ ‘oot3”’ instead of ‘*-o13”; p. 228, footnote, after ‘*‘ XCVI.” insert ‘ Part 11.” ; p 252, line 17, before ‘‘ being”’ insert ‘‘the whole” ; p. 256, line 18, insert parenthesis marks before ‘‘since” and after * ae "; p. 348, line 8 from foot, for ‘‘ 1071” read ‘10-19 ” : 74 line 5 from foot, for from foot, insert *‘ half” after ‘‘ than”; p. 398, line 3 of foot- note, for ‘‘praecendentium ” read ‘‘ preecedentium”; p. 401, footnote, delete ‘‘or oblong-rectangle-based”’; p. 403, line 25, for **§ 52” read ‘*§ 53”; p. 409, line 5 from foot, for ‘‘ Caig- nard” read ‘‘Cagniard”; p. 441, line 4, for ‘‘” read ‘*g”: line 8, for ‘*x?” read ‘‘g?”; p. 442, line 10 from foot, for <°29” read ‘°46”: line 2 from foot, for ‘‘27” read “42”; p. 451, line 13, for ‘‘ forces” read ‘‘force”; p. 459, line 5, for ‘‘forcives” (first) read ‘‘ forcive’”’ ; p. 478, line 5 of foot- note, delete comma after ‘‘force’’; p. 479, line 8, for ‘‘ 15” read ‘‘12”: line 9, for ‘‘-18” read ‘‘-225”5 p. 480, line 16, for ‘‘of” (after ‘‘law”’) read ‘‘if” ; p. 483, line 7, for ‘*18 ” read ‘* °225.” ? THE additions to the Zoological Society's Gardens during the past week include a Rhesus Monkey (Macacus rhesus) from India, presented by Mr. E. G. Mills; a Short-tailed Vole (Aruicola agrestis, var.), British, presented by Mr. A. Thomas ; a Leadbeater’s Cockatoo (Cacatua leadbeaterz) from Australia, presented by Lieut.-Colonel G. E. E. Blunt; a Laughing Kingfisher (Dacelo gigantea), presented by Mr. Thomas A. de Wolf ; eleven Long-nosed Crocodiles (Crocodilus cataphractus) from Assay, South Nigeria, presented by Mr. W. J. Bowker ; a West African Python (Python sebae) from West Africa, presented by Mr. J. S. Budgett ; two One-wattled Cassowaries (Casw- arius untappendiculatus), a Blue-necked Cassowary (Casuarius intensus) from New Guinea, a Little Rock Wallaby (Petrogale concinna), two Regent Birds (Serzcuus melinus) from Australia, a Ring-necked Parrakeet (Pa/aeornés torguata, var.) from India, a Serrated Terrapin (Chrysemys scripta) from North America, a Grooved Tortoise (Zestudo calcarata) from South Africa, deposited. OUR ASTRONOMICAL COLUMN, HoumMeEs’ CoMErT 1899 d (1892 III.).— Ephemerts for 12h. Greenwich Mean Time. 1899. R.A Decl. Br. a r2 (vA-2) h. m. Ss. oo. a“ Sept. 14 3 9 551 43 16 46°9 15 9 16°48 43 29 52°3 16 9 25°29 43 42 494 17 9 31 90 43.55 38°90 0°1777 005636 18 9 36°31 44 8 176 19 9 38°47 44 20 480 20 9 38°37 44 33 88 21 3 9 35°98 44.45 19°'7 01758 0705727 On the 20th, the comet ceases to move eastward, and com- mences to travel in a north-westerly path through Perseus. NO. 1559, VOL. 60] NATURE “‘second”’ read ‘century’; p. 396, line 8 | 487 VANADIUM IN METEORITES.—In a paper contributed to Mem. Soc. Degli. Spett. [tal. (vol. xxviii. pp. 113-119), M. M. B, Hasselberg gives the results of an extensive investigation he has been making into the constitution of meteorites. Thirty-one different specimens have been examined, and photographs taken of their spectra when volatilised in the electric arc, the region extending from A 4268°78 to A 4444°40. Tables are given showing the relative intensities of the characteristic vanadium lines, the discussion of which leads the author to give the following conclusions :— (1) The quantity of vanadium present in meteorites is exceed- ingly small, but the sensible differences found in the several specimens leave no doubt of the reality of its presence. The meteorites, of New Concord, Lundsgarden, 1’Aigle, Kniahynia and Alfianello are cited as showing the metal most easily. (2) There is a distinct difference between zroz meteorites and stony meteorites, the former containing xo trace of vana- dium, while the latter generally contain it in greater or less quantity. | (3) In the meso-siderites, of intermediate composition, the presence of vanadium is very doubtful, though faint indica- tions are often found. With regard to the Nejed and Obernkirchen meteorites, which are ferro-siderites, the author states that he has specially looked for the lines found by Lockyer at AA 4112°5-4119°6, but without success, his vanadium spectrum not containing lines of these wave-lengths. Measures of photographs of comparison spectra of vanadium and Nejed meteorite fail to show the lines, and he gives a list of nine vanadium lines in this region which do not appear in the meteorite, and there- fore is led to regard these two as not being exceptions to the rule that iron meteorites contain no trace of vanadium. CoRDOBA PHOTOGRAPHS OF STAR-CLUSTERS.—We have recently received from Dr. S. C. Chandler a volume en- titled ** Cordoba Photographs,” containing the measures and computations made by the late Dr. B. A. Gould, from the photographs of star-clusters obtained at the Argentine National Observatory. Dr. Gould commenced the undertaking in 1872, at the Cordoba Observatory, which was placed at his disposal by the Argentine Government. After his death in 1896 the re- maining portions were completed by his assistant, Mr. G. E. Whitaker, who had worked with Dr. Gould for eleven years. The volume is printed in duplicate throughout, in Spanish and English. In the first 41 pages a detailed description is given of the origin of the work, and the method of carrying it out, with full particulars and explanation of the methods of measurement and computation adopted. Two series of photographs were obtained, one with an object-glass formerly the property of Mr. Rutherford, of 28°6 cm. aperture, and the other with a new glass constructed by Fitz, under Rutherford’s superintendence. On Dr. Gould’s return to New York in 1885 he had over 1200 plates, besides those of the moon, planets, comets, &c. Of these 281 were fully measured, giving the positions of over 11,000 stars. In addition 315 plates of 96 double stars have also been measured. The material thus made available was so great that it was decided to add no new measures, but proceed with the computations. For this Dr. Gould devised methods of applying corrections for cali- bration of the micrometer scale, expansion-coefficients of the glass plates, and the reduction of the measures to rectangular coordinates. The star clusters are restricted to the Southern Hemisphere with only two exceptions, P/ezades and Praesefe. Each plate was obtained by exposing first for eight minutes, then moving the telescope slightly in R.A. without jar, after which a second exposure of eight minutes was given. Finally the stars were allowed to trail across the plate to give direction of diurnal motion. For some of the plates a third exposure was given instead of obtaining a trail. All the plates were albumenised to prevent distortion of the films, and there has been no trouble from this cause. Various electrical and other contrivances were tried with the telescope, but most of the work was directed by a heavy pendulum as governor. To explain the method of computation, the reduction of a plate of the Pleiades is given with full details of the calculations. The remainder of the volume, pp. 50-482, consists of the final determined positions of 9144 stars in 37 clusters, each accompanied with its own chapter of explanation. There is a chart of each cluster, showing all the stars considered, to ‘a scale of about 18” = 1 mm. ae NATURE [SEPTEMBER 14, 1899 UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Mr. R. P. PARANJPYE, the Indian senior wrangler, has been awarded a special scholarship of 200/. by the Secretary of State, partly as a recognition of his remarkable and distinguished success, and partly to enable him to take the M.A. degree. Ir is announced that the annual distribution of medals and prizes obtained by the students of the Royal College of Science will take place in the lecture theatre, of the Victoria and Albert Museum on Thursday, October 5, when Prof, A. W. Riicker, F.R.S., will deliver an address. A cory of the Calendar of the Durham College of Science, Newcastle-upon-Tyne, has been received. The college forms an important part of the University of the north of England. The degrees of Durham in science and letters and its diplomas in engineering are open to students of the college. The courses of instruction in all natural sciences and in every department of engineering are practical and complete, and the chemical, physical and engineering laboratories are well equipped. In addition to the biological laboratories at the College, a marine biological laboratory has lately been opened at Cullercoats, and by the generosity of the Northumberland Sea Fisheries Com- mittee is available for college students. The agricultural department has been carefully organised, and has been entrusted with the scientific direction of the farm acquired for the purpose of experiment and demonstration by the County Council of Northumberland. Many friends of education will regret to learn of the death of Mr. Theodore Beck, principal of the Mahomedan College at Aligarh, at forty years of age. Writing to the 7zmes, a friend of the late principal says :—‘‘ Men who were at Cambridge in the early eighties will remember Theodore Beck, scholar of Trinity and president of the union, as one of the most conspicuous figures in the University life of the time. He disappeared from the horizon of his English friends, as do all men who go out to India, when he accepted the post of principal in the recently founded college in Aligarh. When he landed in India in 1883 Sir Syed Ahmad was giving practical shape to that great rationalistic movement which was to regenerate the Mussulmans of India. Beck found himself thrown into the midst of a com- munity the bulk of which was sullenly hostile to the English and all their ways. Sir Syed Ahmad saw that his people did not need to acquire the sciences of Europe alone, but also to readjust their ideals by an English standard ; for such a change it was necessary not only that they should learn the matter of English text-books, but should also learn to love and admire individual Englishmen and follow them in the ordering of their lives. If Sir Syed was the founder, Theodore Beck was no less certainly the builder of the college in Aligarh and of the large hopes with which it is synonymous. It was he who gave practical form to the generous aspirations in Sir Syed’s mind, and who built up the internal organisation of the college so that it has become the type of a new system of collegiate edu- cation in India.” SCIENTIFIC SERIALS. In the Journal of Botany for August and September, Mr. W. West, jun., contributes a description of some Oscil- latorioidez from the plankton, including a new marine species, Oscillatoria capitata, which is figured; Mr. Spencer Le M. Moore, in Part v. of his ‘‘ Alabastra diversa,”’ describes a number of new species of flowering plants, and Dr. A. B. Rendle several new grasses from South Africa; Mr. J. W. White adds Redus Bucknalli, sp.n., to the already too numerous British brambles. THE Journal of the Royal Microscopical Society for August contains a continuation (Part v.) of Mr. F. W. Millett’s report on the recent Foraminifera of the Malay Archipelago collected by Mr. A. Durrand, and a paper by the president, Mr. E. M. Nelson, on the evolution of the fine adjustment of the microscope, in which a new and important adjustment is lescribed, invented by Reichert. Among the more important paragraphs in the summary of current researches relating to zoology, botany and microscopy is a description of a new electrically heated stage, also invented by Reichert. NO. 1559, VOL. 60] SOCIETII-S AND ACADEMIES. PARIs. Academy of Sciences, September 4.—M. Maurice Lévy in the chair.— Observations of Swift’s Comet (1899 a), made with the large equatorial of the Bordeaux Observatory, by MM. G. Rayet and A. Féraud. The observations, twenty-one in num- ber, extend from May 18 to July 15. The mean positions for 1899 are worked out both for the comet and comparison stars. —Remarks by the Director of the ‘‘ Instituto y observatorio de Marina de San Fernando,” offering facilities to astronomers wishing to observe the coming total eclipse of the sun in Spain. —Observations of the planet EP (J. Mascart, August 26, 1899), made at the Observatory of Besancon by M. Chofardet. Note by M. L. J. Gruey. The eight observations given extend from August 29 to September 1, the positions of the comparison stars and the apparent positions of the planets being given.—Obsery- ations of the Perseids made at Athens, by M. D. Eginitis.— On the surfaces of the fourth degree which admit an integral of the total differential of the first species, by Mr. Arthur Berry.— On the solidification of hydrogen, by Prof. James Dewar. A tube containing liquid hydrogen, and surrounded by another vacuum jacketed tube containing liquid hydrogen boiling in a vacuum, solidifies, the lower portion being a clear ice-like solid, the upper a solid froth. The density was found to be approximately ‘086, the liquid at its boiling point being ‘07. Solid hydrogen melts when the pressure of its saturated vapour amounts to 55 mm. The melting point, as determined by two gas thermometers con- taining hydrogen under reduced pressure, was found to be 16° above the absolute zero at 35 mm. pressure. The lowest temperature attained in these experiments was about — 259° C., or 14° absolute. —On the mode of growth in spirals of appendices in course of regeneration in the Arthropods, by M. Edmond Bordage. CONTENTS. PAGE The Correspondence of Huygens. By Dr. J. L. E. Dreyer. cere o 6 oO ONOREINO 457 Metaphysics of Ee oom 458 Our Book Shelf :— Koehler : ‘f An Account of the Deep-Sea Ophiuroidea collected by the Royal Indian Marine Survey Ship Investigator) Seman) +8 + 0) © nv em) Letters to the Editor :— Dark Lightning.—Prof. R. W. Wood. ..... 460 Tides in the Bay of Fundy.—W. H. Wheeler. . . 461 Ethnographical Collections in Germany 461 The Dover Meeting of the British Association . . 463 Inaugural Address by Prof. Sir Michael Foster, K.C.B., Sec.R.S., President of the Association . 464 Section A.— Mathematics and Physics.— Opening Address by Prof, J. H. Poynting, F.R.S., President of the Section. .... oun 470 Section B.—Chemistry. (W2th Pierant 1 Opening Address by Dr. Horace T. Brown, F.R.S., President of the Section . 474 Notes. (J/lustrated.). .. ++. 483 Our Astronomical Column :— Holmes’ Comet 1899 d@ (1892 III.) 487 Vanadium in Meteorites . : 487 Cordoba Photographs of Star- ane A 487 University and Educational Intelligence 488 Scientific Serials . 488 Societies and Academies... . 488 NATURE 489 THURSDAY, SEPTEMBER 21, 1899. iGEIPSES. The Indian Eclipse, 1898. Edited by E. W. Maunder, F.R.A.S. Pp. xii +172. (London: Hazell, Watson, and Viney, 1899.) The Story of Eclipses. By G. F. Chambers, F.R.A.S. Pp. viii + 259. (London: George Newnes, 1899.) OTWITHSTANDING the fact that the totally eclipsed sun can only be observed for something like three hours in a century, an extensive literature dealing with the phenomena has come into existence. Two distinct branches of the subject may be recognised —one referring chiefly to past eclipses, which have their principal use in chronology, and the other bearing upon the more recent eclipses, in which attempts to extend our knowledge of the sun itself have taken the place of superstitious fear. Of the two books named above, the first belongs to the latter category, while the other is apparently intended to give a simple survey of the whole subject. The first book forms the report of the two expeditions organised by the British Astronomical Association to observe the total eclipse of January 22, 1898, and gives an account of the objects and results of the observations made. The organisation of the expedition, combining science with pleasure, appears to have been in capable hands, and the Association is to be congratulated on the fact that some of those who took part in the observ- ations gave the first place to science. Mr. Maunder’s party at Talni was especially active, but Mr. Bacon’s party appears to have arrived at Buxar too late to under- take anything very serious. The duplication of results, which - inevitably followed from the fact that the eclipse was well visible to observers all along the line, to a certain extent reduces the value of the work at any par- ticular station, each party probably being able to claim but little in the way of novel results which would not otherwise have been brought to light. Thusit is that the more specially valuable results of these expeditions are those obtained by Mr. Evershed and Mrs. Maunder— the former with the ultra-violet region of his photographs of the so-called “flash” and coronal spectra, and the latter indicating the best means of photographing the long extensions of the corona. Miscellaneous observ- ations of the usual character are included in the report, as well as a chapter of hints for future work. No effort has been spared to make the report attractive; the general story of the expeditions forms very interesting reading, and the explanatory matter is very clear and concise, while the numerous illustrations from photo- graphs—not all of scientific value, however—are beautifully reproduced. The chief scientific interest undoubtedly belongs to Mr. Evershed’s fine photographs, taken with a very modest prismatic camera, and the full discussion of these wlll doubtless yield valuable results. Mr. Chambers’s book has been written primarily for the benefit of the English-speaking people who may expect to witness the phenomena of the total eclipse of May 28, 1900, in Spain or the United States. A very small part, however, is given to the information which seems to us what the average probable observer will desire to know NO. 1560, VOL. 60] the greater part of the book being a sort of descriptive catalogue of eclipses, ancient and modern, including lunar eclipses. A complete want of proportion is, in fact, shown throughout ; for instance, more than a dozen pages are taken up by an attempt to prove that the back- ward motion of the shadow on the dial of Ahaz was caused by a partial eclipse, while only two pages are given to the three important eclipses of 1893, 1896, and 1898. The author appears to have entirely failed to- grasp the enormous advances which have lately beem made, and leaves his readers in complete ignorance of the more important observations which now occupy the attention of astronomers during eclipses ; thus, less than a single page is occupied by references to the spectroscope, and most of the statements made are now known to be erroneous. Finally, in his desire to- satisfy the thirst for knowledge which it is one of the main objects of this series of books to create, the author refers almost entirely to works which comparatively few will be able to read, and quite omits to mention even the late Mr. Ranyard’s classical compilation. The only redeeming features of the book, bearing in mind its more particular aim, are the thirty-three pages of matter describing the general phenomena of a total eclipse, and the appendix indicating how one may get to Spain or Portugal for the next eclipse. A FRENCH WRITER ON CLASSIFICATION. Aperwus de Taxinomte Générale. Par J.-P. Durand. (de Gros). Pp. 265. (Paris: Félix Alcan, 1899.) | ese scientific worker who takes in hand the task. of classifying the objects of his study comes thereby into relation with the domain of logic and metaphysics. Whether this be done consciously or unconsciously, the classifier cannot avoid raising and dealing with questions. which are the concern of philosophy as well as of physical science. The author of the book before us, starting from the position that all taxinomy (which form he prefers, on etymological grounds, to the more usual “taxonomy ”) must conform to logical requirements, proceeds to give a careful and elaborate analysis of the principles of logical division so far as they are involved in the classifications. of science. To this he adds a free criticism, mainly from, the logical point of view, of the labours of scientific taxinomists ; and in the last place he furnishes some suggestions for the guidance of future workers in the same field. His preliminary analysis, if not very pro- found in its reasoning, is marked by the lucidity and good sense so constantly to be met with in writers of his nation. It does not add very much, except in clearness and fulness of treatment, to what is to be found in most standard works on logic, nor does it always avoid insist- ing at considerable length on the trite and obvious. This, however, evidently arises from the anxiety of the author to make himself thoroughly understood, and to allow no omission or ambiguity in the steps of his argu- ment. He has certainly succeeded in expressing him- self so clearly that whatever may be thought of his doctrine, no mistake can arise as to his meaning. With regard to the critical portion of the work, it must be granted that most of the author’s strictures are, from his own point of view, well founded. Nevertheless, it may be questioned whether the logical blots he contrives to_hit We 490 NATURE [SEPTEMBER 21, 1899 in the work of Mill, Littré, Bichat and others, have really the grave importance or have produced the disastrous results which he attributes to them. Ml§ll’s use of certain terms, such as “abstract” and “ concrete general,” is no doubt open to serious objection ; but there is much like- lihood that his conceptions on these points did not really differ from those of his critic; and the same smz/atis mutandis may probably be said of the logical slips of Bichat and Haeckel. It would be unfair to accuse the author of pedantry, but at the same time it is not certain that he allows sufficiently for that faculty of the human mind which frequently leads it to conclusions practically sound by processes that are logically quite indefensible. The constructive part of the book is hardly so strong as the critical. Here, however, M. Durand does excel- lent service in emphasising the point, even now im- perfectly grasped by many systematists, that no classification of organisms can be really natural unless it proceeds on a phylogenetic basis. Where the phylo- geny is unknown, a natural classification is so far impossible. In such cases an artificial classification, based on characters more or less arbitrarily selected, may be provisionally adopted as a substitute ; and, so long as it is not treated as final, may answer all ordinary purposes without detriment to the advance of knowledge. From failure to recognise the practical value of such temporary expedients, M. Durand, as it seems to us, is ied to adopt an unduly pessimistic tone with regard to he future of biological taxinomy. For a long time to come zoologists and botanists will doubtless have to proceed by the method of successive approximation ; and even if the ideal result should be finally unattain able, enough will probably be gained to satisfy all demands but those of the logical purist. M. Durand’s able and acute commentary may be studied with profit by all who engage in taxinomic work themselves, or who wish to appreciate that of others The most serious charge we have to bring against him is that of making scientific molehills into logical and metaphysical mountains. ASD: OUR BOOK SHELF. Die Welt als That. Umrisse einer Weltansicht auf naturwissenschaftlichen Grundlage. By J. Reinke. Pp. iv + 483. (Berlin: Gebriider Paetel, 1899.) IN this work Prof. Reinke sets forth his philosophic and scientific creed, his conceptions of nature and the uni- verse, of plant, beast, man, and God. The book is divided into five parts. The first is entitled ‘“ Subject and Object of the Study of Nature,” and discusses things and ideas, time and space, causality, chance, intelligence, and other metaphysical questions. The second part, under the heading of “The World-Stage,” deals with the material universe and with the conceptions of matter, force and direction. The third part discusses ‘The Nature of Life,’ and in thirteen chapters treats of the SID *Newton, Prof. —Migration of Birds : 15 Lankester, Prof. E. Ray.—Plankton and Physical Condi- tions of the English Channel... tA) *Newton, Prof.—Zoology of the Sandwich Islands sae LOO Sedgwick, Mr. A.—Coral Reefs of the Indian Region... 30 Geography. Murray, pu Johns hace and Chemical Constants of Sea Water ee : oa 088 LOO, Economic Sctence and Statistics. Price, Mr. L. L.—Future Dealings in Raw Produce... 5 Sedgwick, Prof. H.—State Monopolies in other Countries (413 13s. 6d. in hand) ... ds Bae oo a8 Mechanical Science. *Preece, Sir W. H.—Small Screw eas (£17 Is. 2d, in hand) Anthropology *Evans, Mr. A. J.—Silchester Excavation ‘ 10 *Penhallow, Prof. D. P.—Ethnological Survey of. Canada 50 *Tylor, Prof. E. B.—New Edition of ‘* Anthropological Notes and Queries” 40 *Garson, Dr. ie G.—Age of Stone Circles (balance in hand) ‘ a Bo *Read, Mr. C. H.—Photographs - of Anthropological Interest .. 10 *Brabrook, Mr. E. W.—Mental and Physical Condition of Children ond 5 Read, Mr. C. H. —Ethnography of the Malay Peninsula 25 * Re-appointed. NO. 1560, VOL. 60] Physiology. *Schiafer, Prof. E. A.—Physiological Effects of Peptone... 20 Schafer, Prof. E. A.—Comparative Histology of Supra- renal Capsules... 20 *Gotch, Prof. F.— —Comparative Histology of "Cerebral Cortex 20 5 Gotch, Prof. F.—Electrical Changes in Mammalian Nerves Fag) 209 Starling, Dr. —Vascular Supply of Secreting Glands ... 10 Botany. *Darwin, Mr. F.—Assimilation in Plants (£6 6s. Sd. in hand) *Farmer, Prof. ne B.—Fertilisation in n Pheeophyceze Big SY Corresponding Socteties. *Meldola, Prot. R.—Preparation of Report... ace Peay» Zs) AINS SECTION C. GEOLOGY. OPENING ADDRESS BY SIR ARCHIBALD GEIKIE, D.C.L., D.Sc., F.R.S., PRESIDENT OF THE SECTION. AMONG the many questions of great theoretical importance which have engaged the attention of geologists, none has in late years awakened more interest or aroused livelier controversy than that which deals with time as an element in geological history. The various schools which have successively arisen— Cataclysmal, Uniformitarian, and Evolutionist—have had each its own views as to the duration of their chronology, as well as to the operations of terrestrial energy. But though holding different opinions, they did not make these differences matter of special controversy among themselves. About thirty years ago, however, they were startled by a bold irruption into their camp from the side of physics. They were then called on to re- form their ways, which were declared to be flatly opposed to the teachings of natural philosophy. Since that period the discussion then started regarding the age of the earth and the value of geological time has continued with varying animation. Evidence of the most multifarious kind has been brought forward, and arguments of widely different degrees of validity have been pressed into service both by geologists and palzontologists on one side, and by physicists on the other. For the last year or two there has been a pause in the con- troversy, though no general agreement has been arrived at in regard to the matters in dispute. The present interval of comparative quietude seems favourable for a dispassionate review of the debate. I propose, therefore, to take, as perhaps a not inappropriate subject on which to address geologists upon a somewhat international occasion like this present meeting of the British Association at Dover, the question of Geological Time. In offering a brief history of the discussion, I gladly avail myself of the opportunity of enforcing one of the lessons which the discussion has impressed upon my own mind, and to point a moral which, as it seems to me, we geologists may take home to ourselves from a consideration of the whole question. There is, I think, a practical outcome which may be made to issue from the controversy in a combination of sympathy and co-operation among geologists all over the world. A lasting service will be rendered to our science if by well-concerted effort we can place geological dynamics and geological chronology on a broader and firmer basis of actual experiment and measurement than has yet been laid. To understand aright the origin and progress of the dispute regarding the value of time in geological speculation, we must take note of the attitude maintained towards this subject by some of the early fathers of the science. Among these pioneers none has left his mark more deeply graven on the foundations of modern geology than James Hutton. To him, more than to any other writer of his day, do we owe the doctrine of the high antiquity of our globe. No one before him had ever seen so clearly the abundant and impressive proofs of this remote antiquity recorded in the rocks of the earth’s crust. In these rocks he traced the operation of the same slow and quiet processes which he observed to be at work at present in * Re-appointed. ee es SEPTEMBER 21, 1899] NATURE 497 gradually transforming the face of the existing continents. When he stood face to face with the proofs of decay among the mountains, there seems to have arisen uppermost in his mind the thought of the immense succession of ages which these proofs revealed to him. His observant eye enabled him to see ‘‘ the operations of the surface wasting the solid body of the globe, and to read the unmeasurable course of time that must have | flowed during those amazing operations, which the vulgar do not see, and which the learned seem to see without wonder” (‘‘ Theory of the Earth,” vol. i. p. 108). In contemplating the stupendous results achieved by such apparently feeble forces, Hutton felt that one great objection he had to contend with in the reception of his theory, even by the scientific men of his day, lay in the inability or unwillingness of the human mind to admit such large demands as he made on the past. ‘* What more can we require?” he asks in summing up his conclusions ; and he answers the question in these memorable words : *‘ What more can we require? Nothing but time. It is not any part of the process that will be disputed; but after allowing all the parts, the whole will be denied ; and for what ?—only because we are not disposed to allow that quantity of time which the ablution of so much wasted mountain might require” (of. c7v. vol. ii. p. 329). Far as Hutton could follow the succession of events registered in the rocky crust of the globe, he found himself baffled by the closing in around him of that dark abysm of time into which neither eye nor imagination seemed able to penetrate. He well knew that, behind and beyond the ages recorded in the oldest of the primitive rocks, there must have stretched a vast earlier time, of which no record met his view. He did not attempt to speculate beyond the limits of his evidence. ‘‘I do not pretend,” he said, ‘‘to describe the beginning of things ; I take things such as I find them at present, and from these I reason with regard to that which must have been (of. c2¢. vol. i. p- 173, 70¢e). In vain could he look, even among the oldest formations, for any sign of the infancy of the planet. Hecould only detect a repeated series of similar revolutions, the oldest of which was assuredly not the first in the terrestrial history, and he concluded, as ‘“‘the result of this physical inquiry, that we find no vestige of a beginning, no prospect of an end ” (04. cit. vol. i. p. 200). This conclusion from strictly geological evidence has been impugned from the side of physics, and, as further developed by Playfair, has been declared to be contradicted by the principles of natural philosophy. But if it be considered on the basis of the evidence on which it was originally propounded, it was absolutely true in Hutton’s time and remains true to-day. That able reasoner never claimed that the earth has existed from all eternity, or that it will go on existing for ever. He admitted that it must have hada beginning, but he had been unable to find any vestige of that beginning in the structure of the planet itself. And notwithstanding all the multiplied researches of the century that has passed since the immortal ‘‘ Theory of the Earth” was published, no relic of the first condition of our earth has been found. We have speculated niuch, indeed, on the subject, and our friends the physicists have speculated still more. Some of the speculations do not seem to me more philosophical than many of those of the older cosmogonists. As far as trustworthy evidence can be drawn from the rocks of the globe itself, we do not seem to be nearer the discovery of the beginning than Hutton was. The most ancient rocks that can be reached are demonstrably not the first-formed of all. They were preceded by others which we know must have existed, though no vestige of them may remain. It may be further asserted that, while it was Hutton who first | impressed on modern geology the conviction that for the adequate comprehension of the past history of the earth vast | periods of time must be admitted to have elapsed, our debt of obligation to him is increased by the genius with which he linked the passage of these vast periods with the present economy of nature. He first realised the influence of time as a factor in geological dynamics, and first taught the efficacy of the quiet and unobtrusive forces of nature. His predecessors and contemporaries were never tired of invoking the more vigorous manifestations of terrestrial energy. They saw in the com- position of the land and in the structure of mountains and valleys memorials of numberless convulsions and cataclysms. In Hutton’s philosophy, however, ‘‘it is the little causes, long continued, which are considered as bringing about the greatest changes of the earth ” (‘‘ Theory of the Earth,’ vol. ii. p. 205). NO. 1560, VOL. 60] And yet, unlike many of those who derived their inspiration from his teaching, but pushed his tenets to extremes which he doubtless never anticipated, he did not look upon time as a kind of scientific fetich, the invocation of which would endow with efficacy even the most trifling phenomena. As if he had fore- seen the use that might be made of his doctrine, he uttered this remarkable warning : ‘* With regard to the effect of time, though the continuance of time may do much in those operations which are extremely slow, where no change, to our observation, had appeared to take place, yet, where it is not in the nature of things to produce the change in question, the unlimited course of time would be no more effectual than the moment by which we measure events in our observations.” (0f. cé¢. vol. i. p. 44). We thus see that in the philosophy of Hutton, out of which so much of modern geology has been developed, the vastness of the antiquity of the globe was deduced from the structure of the terrestrial crust and the slow rate of action of the forces by which the surface of the crust is observed to be modified. But no attempt was made by him to measure that antiquity by any of the chronological standards of human contrivance. He was content to realise for himself and to impress upon others that the history of the earth could not be understood, save by the admission that it occupied prolonged though indeterminate ages in its accomplishment. And assuredly no part of his teaching has been more amply sustained by the subsequent progress of research, Playfair, from whose admirable ‘‘Illustrations of the Hut- tonian Theory ” most geologists have derived all that they know directly of that theory, went a little further than his friend and master in dealing with the age of the earth. Not restricting himself, as Hutton did, to the testimony of the rocks, which showed neither vestige of a beginning nor prospect of an end, he calledrin the evidence of the cosmos outside the limits of our planet, and declared that in the firmament also no mark could be discovered of the commencement or termination of the present order, no symptom of infancy or old age, nor any sign by which the future or past duration of the universe might be estimated (** Illustrations of the Huttonian Theory, § 118). He thus ad- vanced beyond the strictly geological basis of reasoning, and committed himself to statements which, like some made also by Hutton, seem to have been suggested by certain deductions ot the French mathematicians of his day regarding the stability of the planetary motions. His statements have been disproved by modern physics ; distinct evidence, both from the earth and the cosmos, has been brought forward of progress from a begin- ning which can be conceived, through successive stages to an end which can be foreseen. But the disproof leaves Hutton’s doctrine about the vastness of geological time exactly where it was, Surely it was no abuse of language to speak of periods as being vast, which can only be expressed in millions of years. It is easy to understand how the Uniformitarian school, which sprang from the teaching of Hutton and Playfair, came to believe that the whole of eternity was at the disposal of geologists. In popular estimation, as the ancient science of astronomy was that of infinite distance, so the modern study of geology was the science of infinite time. It must be frankly conceded that geologists, believing themselves unfettered by any limits to their chronology, made ample use of their imagined liberty. Many of them, following the lead of Lyell, to whose writings in other respects modern geology owes so deep a debt of gratitude, became utterly reckless in their demands for time, demands which even the requirements of their own science, if they had adequately realised them, did not warrant. The older geolo- gists had not attempted to express their vast periods in terms of years. The indefiniteness of their language fitly denoted the absence of any ascertainable limits to the successive ages with which they had to deal. And until some evidence should be discovered whereby these limits might be fixed and measured by human standards, no reproach could justly be brought against the geological terminology. It was far more philosophical to be content, in the meanwhile, with indeterminate expressions, than from data of the weakest or most speculative kind to attempt to measure geological periods by a chronology of years or centuries. In the year 1862 a wholly new light was thrown on the question of the age of our globe and the duration of geological ume by the remarkable paper on the Secular Cooling of the Earth communicated by Lord Kelvin (then Sir William Thomson) to the Royal Society of Edinburgh (Zyvans. Roy. Soc. Edin., vol, xxili,, 1862). In this memoir he first developed his now 498 NATURE [SEPTEMBER 21, 1899 well-known argument from the observed rate o1 increase of temperature downwards from the surface of the land. He astonished geologists by announcing to them that some definite limits to the age of our planet might be ascertained, and by declaring his belief that this age must be more than 20 millions, but less than 400 millions, of years. Nearly four years later he emphasised his dissent from what he considered to be the current geological opinions of the day by repeating the same argument in a more pointedly antagonistic form in a paper of only a few sentences, entitled, ‘‘ The Doctrine of Uniformity in Geology briefly refuted ” (Proc. Roy. Soc. Edin., vol. v. p. 512, December 18, 1865). Again, after a further lapse of about two years, when, as President of the Geological Society of Glasgow, it became his duty to give an address, he returned to the same topic and arraigned more boldly and explicitly than ever the geology of the time. He then declared that ‘‘a great reform in geological speculation seems now to have become necessary,” and he went so far as to affirm that ‘‘it is quite certain that a great mistake has been made—that British popular geology at the present time is in direct opposition to the principles of natural philosophy” ( 7vavs. Geol. Soc. Glasgow, vol. iii., February 1868, pp- I, 16). In pressing once more the original argument de- rived from the downward increase of terrestrial temperature, he now reinforced it by two further arguments, the one based on the retardation of the earth’s angular velocity by tidal friction, the other on the limitation of the age of the sun. These three lines of attack remain still those along which the assault from physics is delivered against the strongholds of geology. Lord Kelvin has repeatedly returned to the charge since 1868, his latest contribution to the controversy having been pronounced two years ago.’ While his physical arguments re- main the same, the limits of time which he deduces from them have been successively diminished. The original maximum of 400 millions of years has now been restricted by him to not much more than 20 millions, while Prof. Tait grudgingly allows something less than 10 millions (‘‘ Recent Advances in Physical Science,” p. 174). Soon after the appearance of Lord Kelvin’s indictment of modern geology in 1868, the defence of the science was taken up by Huxley, who happened at the time to be President of the Geological Society of London. In his own inimitably brilliant way, half seriously, half playfully, this doughty combatant, with evident relish, tossed the physical arguments to and fro in the eyes of his geological brethren, as a barrister may flourish his brief before a sympathetic jury. He was willing to admit that ‘* the rapidity of rotation of the earth #ay be diminishing, that the sun may be waxing dim, or that the earth itself »zay be cool- ing.” But he went on to add his suspicion that ‘‘ most of us are Gallios, ‘ who care for none of these things,’ being of opinion that, true or fictitious, they have made no practical difference to the earth, during the period of which a record is preserved in stratified deposits” (Presidential Address, Quart. Journ. Geol. Soc., 1869). For the indifference which their advocate thus professed on their behalf most geologists believed that they had ample justification. The limits within which the physicist would cir- cumscribe the earth’s history were so vague, yet so vast, that whether the time allowed were 400 millions or 100 millions of years did not seem to them greatly to matter. After all, it was not the time that chiefly interested them, but the grand succession of events which the time had witnessed. That succession had been established on observations so abundant and so precise that it could withstand attack from any quarter, and it had taken as firm and lasting a place among the solid achievements of science as could be claimed for any physical speculations whatsoever. Whether the time required for the transaction of this marvellous earth-history was some millions of years more or some millions of years less did not seem to the geologists to be a question on which their science stood in antagonism with the principles of natural philosophy, but one which the natural philosophers might be left to settle at their own good pleasure. For myself, I may be permitted here to say that I have never shared this feeling of indifference and unconcern. As far back as the year 1868, only a month after Lord Kelvin's first pre- sentation of his threefold argument in favour of limiting the age of the earth, I gave in my adhesion to the propriety of restricting 1“ The Age of the Earth,” being the Annual Address to the Victoria Institute, June 2, 1897. ‘PAZ. Mag., January 1899, p. 66. NO. 1560, VOL. 60] the geological demands for time. I then showed that even the phenomena of denudation, which, from the time of Hutton downwards, had been most constantly and confidently appealed to in support of the inconceivably vast antiquity of our globe, might be accounted for, at the present rate of action, within such a period as 100 millions of years.!- To my mind it has always seemed that whatever tends to give more precision to the chronology of the geologist, and helps him to a clearer con- ception of the antiquity with which he has to deal, ought to be welcomed by him as a valuable assistance in his inquiries. And I feel sure that this view of the matter has now become general among those engaged in geological research. Frank recog- nition is made of the influence which Lord Kelvin’s persistent attacks have had upon our science. Geologists have been led by his criticisms to revise their chronology. They gratefully acknowledge that to him they owe the introduction of important new lines of investigation, which link the solution of the problems of geology with those of physics. They realise how much he has done to dissipate the former vague conceptions as to the duration of geological history, and even when they em- phatically dissent from the greatly restricted bounds within which he would now limit that history, and when they declare their inability to perceive that any reform of their speculations in this subject is needful, or that their science has placed herself in opposition to the principles of physics, they none the less pay their sincere homage to one who has thrown over geology, as over so many other departments of natural knowledge, the clear light of a penetrating and original genius. When Lord Kelvin first developed his strictures on modern geology he expressed his opposition in the most uncompromising language. In the short paper to which reference has already been made he announced, without hesitation or palliation, that he ‘‘ briefly refuted’ the doctrine of Uniformitarianism which had been espoused and illustrated by Lyell and a long list of the ablest geologists of the day. The severity of his judgment of British geology was not more marked than was his unqualified reliance on his own methods and results. This confident assur- ance of a distinguished physicist, together with a formidable array of mathematical formule, produced its effect on some geologists and palzeontologists who were not Gallios. Thus, even after Huxley’s brilliant defence, Darwin could not conceal the deep impression which Lord Kelvin’s arguments had made on his mind. In one letter he wrote that the proposed limitation of geological time was one of his ‘‘sorest troubles.” In another, he pronounced the physicist himself to be ‘fan odious spectre”’ (Darwin’s ‘‘ Life and Letters,” vol. iii. pp. 115, 146). The same self-confidence of assertion on the part of some, at least, of the disputants on the physical side has continued all through the controversy. Yet when we examine the three great physical arguments in themselves, we find them to rest on assumptions which, though certified as ‘‘ probable” or ‘‘ very sure,” are nevertheless admittedly assumptions. The conclusions to which these assumptions lead must depend for their validity on the degree of approximation to the truth in the premisses which are postulated. Now it is interesting to observe that neither the assumptions nor the conclusions drawn from them have commanded universal assent even among physicists themselves. If they were as self- evident as they have been claimed to be, they should at least receive the loyal support of all those whose function it is to pursue and extend the applications of physics. It will be remembered, however, that thirteen years ago Prof. George Darwin, who has so often shown his inherited sympathy in geological investigation, devoted his presidential address before the Mathematical Section of this Association to a review of the three famous physical arguments respecting the age of the earth. Tle summed up his judgment of them in the following words: ‘‘ In considering these three arguments I have adduced some reasons against the validity of the first (tidal friction) ; and have endeavoured to show that there are elements of uncertainty surrounding the second (secular cooling of the earth) ; neverthe- less they undoubtedly constitute a contribution of the first importance to physical geology. Whilst, then, we may protest against the precision with which Prof. Tait seeks to deduce results from them, we are fully justified in following Sir William Thomson, who says that ‘* the existing state of things on the earth, life on the earth—all geological history showing con- 1 Trans. Geol. Soc, Glasgow, vol. iii, (March 26, 1868), p. 189. Sir W. Thomson acknowledged my adhesion in his reply to Huxley's criticism. Op. cit. p. 221. SEPTEMBER 21, 1899] NATURE 499 tinuity of life—must be limited within some such period of past time as 100,000,000 years” (Rep. Brit. Assoc., 1886, p. 517)- More recently Prof. Perry has entered the lists, from the physical side, to challenge the validity of the conclusions so confidently put forward in limitation of the age of the earth. He has boldly impugned each of the three physical arguments. That which is based on tidal retardation, following Mr. Maxwell Close and Prof. Darwin, he dismisses as fallacious. In regard to the argument from the secular cooling of the earth, he con- tends that it is perfectly allowable to assume a much higher conductivity for the interior of the globe, and that this assump- tion would vastly increase our estimate of the age of the planet. As to the conclusions drawn from the history of the sun, he maintains that, on the one hand, the sun may have been repeatedly fed by infalling meteorites, and that, on the other, the earth, during former ages, may have had its heat retained by a dense atmospheric envelope. He thinks that ‘‘almost anything is possible as to the present internal state of the earth,” and he concludes in these words: ‘‘To sum up, we can find no pub- lished record of any lower maximum age of life on the earth, as calculated by physicists, than 400 millions of years. From the three physical arguments, Lord Kelvin’s higher limits are 1000, 400, and 500 million years. I have shown that we have reasons for believing that the age, from all these, may be very consider- ably under-estimated. It is to be observed that if we exclude everything but the arguments from mere physics, the prodadie age of life on the earth is much less than any of the above estimates ; but if the paleontologists have good reasons for demanding much greater times, I see nothing from the physicist’s point of view which denies them four times the greatest of these estimates” (NATURE, vol. li. p. 585, April 18, 1895). This remarkable admission from a recognised authority on the physical side re-echoes and emphasises the warning pronounced by Prof. Darwin in the address already quoted—‘‘at present our knowledge of a definite limit to geological time has so little precision that we should do wrong to summarily reject any theories which appear to demand longer periods of time than hose Sue now appear allowable” (Rep. Brit. Assoc., 1886, p- 518). This ‘‘ wrong,”’ which Prof. Darwin so seriously deprecated, has been committed, not once, but again and again in the history of this discussion. Lord Kelvin has never taken any notice of the strong body of evidence adduced by geologists and palzontologists in favour of a much longer antiquity than he is now disposed to allow for the age of the earth. His own three physical arguments have been successively re-stated, with such corrections and modifications as he has found to be necessary, and no doubt further alterations are in store for them. He has cut off slice after slice from the allowance of time which at first he was prepared to grant for the evolution of geological history, his latest pronouncement being that ‘‘it was more than twenty and less than forty million years, and probably much nearer twenty than forty.”4 But in none of his papers is there an admission that geology and palzontology, though they have again and again raised their voices in protest, have anything to say in the matter that is worthy of consideration. It is difficult satisfactorily to carry on a discussion in which your opponent entirely ignores your arguments, while you have given the fullest attention to his. In the present instance, geologists have most carefully listened to all that has been brought forward from the physical side. Impressed by the force of the physical reasoning, they no longer believe that they can make any demands they may please on past time. They have been willing to accept Lord Kelvin’s original estimate of 100 millions of years as the period within which the history of life upon the planet must be comprised, while some of them have even sought in various ways to reduce that sum nearer to his lower limit. Yet there is undoubtedly a prevalent misgiving, whether in thus seeking to reconcile their requirements with the demands of the physicist they are not tying themselves down within limits of time which on any theory of evolution would have been insufficient for the development of the animal and vegetable kingdoms. It is unnecessary to recapitulate before this Section of the British Association, even in briefest outline, the reasoning of geologists and paleontologists which leads them to conclude that the history recorded in the crust of the earth must have re- quired for its transaction a much vaster period of time than that 1‘ The Age of the Earth, ’ Presidential Address to the Victoria Institute for 1897, p- 10; alsoin PAz/. Mag., January 1899. NO. 1560, VOL. 60] to which the physicists would now restrict it.1 Let me merely remark that the reasoning is essentially based on observations of the present rate of geological and biological changes upon the earth’s surface. It is not, of course, maintained that this rate has never varied in the past. But it is the only rate with which we are familiar, which we can watch and in some degree measure, and which, therefore, we can take as a guide towards the comprehension and interpretation of the past history of our planet. It may be, and has often been, said that the present scale of geological and biological processes cannot be accepted as a trustworthy measure for the past. Starting from the postulate, which no one will dispute, that the total sum of terrestrial energy was once greater than it is now and has been steadily declining, the physicists have boldly asserted that all kinds of geological action must have been more vigorous and rapid during bygone ages than they are to-day ; that volcanoes were more gigantic, earthquakes more frequent and destructive, mountain-upthrows more stupendous, tides and waves more powerful, and com- motions of the atmosphere more violent, with more ruinous tempests and heavier rainfall. Assertions of this kind are temptingly plausible and are easily made. But it is noi enough that they should be made; they ought to be supported by some kind of evidence to show that they are founded on actual fact and not on mere theoretical possibility. Such evidence, if it existed, could surely be produced. The chronicle of the earth’s history, from a very early period down to the present time, has been legibly written within the sedi- mentary formations of the terrestrial crust. Let the appeal be made to that register. Does it lend any support to the affirmation that the geological processes are now feebler and slower than they used to be? If it does, the physicists, we might suppose, would gladly bring forward its evidence as irrefragable confirmation of the soundness of their contention- But the geologists have found no such confirmation. On the contrary, they have been unable to discover any indication that the rate of geological causation has ever, on the whole, greatly varied during the time which has elapsed since the deposition of the oldest stratified rocks. They do not assert that there has been no variation, that there have been no periods of greater activity, both hypogene and epigene. But they maintain that the demonstration of the existence of such periods has yet to be made. They most confidently affirm that whatever may have happened in the earliest ages, in the whole vast succession of sedimentary strata nothing has yet been detected which necessarily demands that more violent and rapid action which the physicists suppose to have been the order of nature during the past. So far as the potent effects of prolonged denudation permit us to judge, the latest mountain-upheavals were at least as stupendous as any of older date whereof the basal relics can yet be detected. They seem, indeed, to have been still more gigantic than those. It may be doubted, for example, whether among the vestiges that remain of Mesozoic or Palaeozoic moun- tain-chains any instance can be found so colossal as those of Tertiary times, such as the Alps. No volcanic eruptions of the older geological periods can compare in extent or volume with those of Tertiary and recent date. The plication and dislocation of the terrestrial crust are proportionately as conspicuously dis- played among the younger as among the older formations, though the latter, from their greater antiquity, have suffered during a longer time from the renewed disturbances of successive periods. As regards evidence of greater violence in the surrounding envelopes of atmosphere and ocean, we seek for it in vain among the stratified rocks. Among the very oldest formations of these islands, the Torridon sandstone of North-west Scotland presents us with a picture of long-continued sedimentation, such as may be seen in progress now round the shores of many a mountain-girdled lake. In that venerable deposit, the enclosed pebbles are not mere angular blocks and chips, swept by a sudden flood or destructive tide from off the surface of the land, and huddled together in confused heaps over the floor of the sea. They have been rounded and polished by the quiet operation of running water, as stones are rounded and polished 1 The geological arguments are briefly given in my Presidential Address to the British Association at the Edinburgh Meeting of 1892. The biological arguments were well stated, and in some detail, by Prof- Poulton, in his Address to the Zoological Section of the Association at the Liverpool Meeting of 1896. 500 NATURE [SEPTEMBER 21, 1899 mow in the channels of brooks or on the shores of lake and sea. ‘They have been laid gently down above each other, layer over. layer, with fine sand sifted in between them, and this deposition has taken place along shores which, though the waters that washed them have long since disappeared, can still be followed for mile after mile across the mountains and glens of the North- west Highlands. So tranquil were these waters that their gentle currents and oscillations sufficed to ripple the sandy floor, to arrange the sediment in laminz of current-bedding, and to separate the grains of sand according to their relative densities. We may even now trace the results of these operations in thin darker layers and streaks of magnetic iron, zircon, and other heavy minerals, which have been sorted out from the lighter quartz-grains, as layers of iron-sand may be seen sifted together by the tide along the upper margins of many of our sandy beaches at the present day. In the same ancient formation there occur also various inter- calations of fine muddy sediment, so regular in their thin alter- mations, and so like those of younger formations, that we cannot but hope and expect that they may eventually yield remains of organisms which, if found, would be the earliest traces of life in Europe. It is thus abundantly manifest that even in the most ancient of the sedimentary registers of the earth’s history, not only is there no evidence of colossal floods, tides and denudation, but there is incontrovertible proof of continuous orderly deposition, such as may be witnessed to-day in any quarter of the globe. The same tale, with endless additional details, is told all through the stratified formations down to those which are in the course of accumulation at the present day. Not less important than the stratigraphical is the palonto- logical evidence in favour of the general quietude of the geo- logical processes in the past. The conclusions drawn from the nature and arrangement of the sediments are corroborated and much extended by the structure and manner of entombment of the enclosed organic remains. From the time of the very earliest fossiliferous formations there is nothing to show that either plants or animals have had to contend with physical conditions of environment different, on the whole, from those in which their successors now live. The oldest trees, so far as regards their outer form and internal structure, betoken an atmosphere neither more tempestuous nor obviously more im- pure than that of to-day. The earliest corals, sponges, crus- taceans, molluscs, and arachnids were not more stoutly con- structed than those of later times, and are found grouped together among the rocks as they lived and died, with no apparent indi- cation that any violent commotion of the elements tried their strength when living, or swept away their remains when dead. But, undoubtedly, most impressive of all the paleontological data is the testimony borne by the grand succession of organic remains among the stratified rocks as to the vast duration of time required for their evolution. Prof. Poulton has treated this branch of the subject with great fulness and ability. We do not know the present average rates of organic variation, but all the available evidence goes to indicate their extreme slowness. They may conceivably have been more rapid in the past, or they may have been liable to fluctuations according to vicissitudes of énvironment.' But those who assert that the rate of biological evolution ever differed materially from what it may now be in- ferred to be, ought surely to bring forward something more than mere assertion in their support. In the meantime, the most philosophical course is undoubtedly followed by those biologists who in this matter rest their belief on their own experience among recent and fossil organisms. So cogent do these geological and palzontological arguments appear, to those at least who have taken the trouble to master them, that they are worthy of being employed, not in defence merely, but in attack. It seems to me that they may be used with effect in assailing the stronghold of speculation and assump- tion in which our physical friends have ensconced themselves and from which, with their feet, as they believe, planted well within the interior of the globe and their heads in the heart of the sun, they view with complete unconcern the efforts made by those who endeavour to gather the truth from the surface and crust of the earth. That portion of the records of ter- ! See an interesting and suggestive paper by Prof. Le Conte on al Periods in the History of the Earth,” Bxdl. Deft. Geology, Uy ity of California, vol. 1. (1895), p. 3133; also one by Prof. Cham- berlin on ‘* The Ulterior Basis of Time-divisions and the Classification of Geological History,” Journal of Geology, vol. vi. (1898), p. 449. NO. 1560, VOL. 60] restrial history which lies open to our investigation has been diligently studied in all parts of the world. A vast body of facts has been gathered together from this extended and com- bined research. The chronicle registered in the earth’s crust, though not complete, is legible and consistent. From the latest to the earliest of its chapters the story is capable of clear and harmonious interpretation by a comparison of its pages with the present condition of things. We know infinitely more of the history of this earth than we’ do of the history of the sun. Are we then to be told that this knowledge, so patiently ac- cumulated from-innumerable observations and so laboriously coordinated and classified, is to be held of none account in comparison with the conclusions of physical science in regard to the history of the central luminary of our system? These conclusions are founded on assumptions which may or may not correspond with the truth. They have already undergone revisicn, and they may be still further modified as our slender knowledge of the sun, and of the details of its history, is increased by future investigation. In the meantime, we decline to accept them as a final pronouncement of science on the subject. We place over against them the evidence of geology and paleontology, and affirm that unless the de- ductions we draw from that evidence can be disproved, we are entitled to maintain them as entirely borne out by the testimony of the rocks. Until, therefore, it can be shown that geologists and palzeon- tologists have misinterpreted their records, they are surely well within their logical rights in claiming as much time for the history of this earth as the vast body of evidence accumulated by them demands. So far as I have been able to form an opinion, one hundred millions of years would suffice for that portion of the history which is registered in the stratified rocks of the crust. But if the paleontologists find such a period too narrow for their requirements, Ican see no reason on the geological side why they should not be at liberty to enlarge it as far as they may find to be needful for the evolution of organised existence on the globe. As I have already remarked, it is not the length of time which interests us so much as the determination of the relative chronology of the events which were transacted within that time. As to the general succession of these events, there can be no dispute. We have traced its stages from the bottom of the oldest rocks up to the surface of the present continents and the floor of the present seas. We know that these stages have followed each other in orderly advance, and that geological time, whatever limits may be assigned to it, has sufficed for the passage of the long stately procession. We may, therefore, well leave the dispute about the age of the earth to the decision of the future. In so doing, however, I should be glad if we could carry away from it something of greater service to science than the consciousness of having striven our best in a barren controversy, wherein concession has all to be on one side and the selection of arguments entirely on the other. During these years of prolonged debate I have often been painfully conscious that in this subject, as in so many others throughout the geological domain, the want of accurate numerical data is a serious hindrance to the progress of our science. Heartily do I acknowledge that much has been done in the way of measurements and experiments for the purpose of providing a foundation for estimates and deductions. But in- finitely more remains to be accomplished. The field of investi- gation is almost boundless, for there is hardly a department of geological dynamics over which it does not extend. The range of experimental geology must be widely enlarged, until every process susceptible of illustration or measurement by artificial means has been investigated. Field-observation needs to be supplemented where possible by instrumental determinations, so as to be made more precise and accurate, and more capable of furnishing trustworthy numerical statistics for practical as well as theoretical deductions. The subject is too vast for adequate treatment here. But let me illustrate my meaning by selecting a few instances where the adoption of these more rigid methods of inquiry might powerfully assist us in dealing with the rates of geological pro- cesses and the value of geological time. Take, for example, the wide range of lines of investigation embraced under the head of Denudation. So voluminous a series of observations has been made in this subject, and so ample is the literature devoted to it, that no department of geology, it might be thought, has been more abundantly and successfully explored. Yet if we look through the pile of memoirs, articles and books, SEPTEMBER 21, 1899] we cannot but be struck with the predominant vagueness of their statements, and with the general absence of such numerical data determined by accurate, systematic and prolonged measure- ment as would alone furnish a satisfactory basis for computations of the rate at which denudation takes place. Some instru- mental observations of the greatest value have indeed been made, but, for the most part, observations of this kind have been too meagre and desultory. A little consideration will show that in all branches of the investigation of denudation opportunities present themselves on every side of testing, by accurate instrumental observation and measurement, the rate at which some of the most universal processes in the geological végzme of our globe are carried on. It has long been a commonplace of geology that the amount of the material removed in suspension and solution by rivers furnishes a clue to the rate of denudation of the regions drained by the rivers. But how unequal in value, and generally how insufficient in precision, are the observations on this topic! A few rivers have been more or less systematically examined, some widely varying results have been obtained from the observ- ations, and while enough has been obtained to show the interest and importance of the method of research, no adequate supply of materials has been gathered for the purposes of accurate deduction and generalisation. What we need is a carefully organised series of observations carried out on a uniform plan, over a sufficient number of years, not for one river only, but for all the important rivers of a country, and indeed for alf the greater rivers of each continent. We ought to know as accu- rately as possible the extent of the drainage-area of each river, | the relations of river-discharge to rainfall and to other meteoro- logical as well as topographical conditions ; the variation in the proportions of mechanical and chemical impurities in the river- water according to geological formations, form of the ground, season of the year and climate. The whole geological régze of each river should be thoroughly studied. The admirable report of Messrs. Humphreys and Abbot on the ‘‘ Physics and Hydraulics of the Mississippi,’’ published in 1861, might well serve asa model for imitation, though these observers neces- sarily occupied themselves with some questions which are not specially geological and did not enter into others on which, as geologists, we should now gladly have further information. Again, the action of glaciers has still less been subjected to prolonged and systematic observation. The few data already obtained are so vague that we may be said to be still entirely ignorant of the rate at which glaciers are wearing down their channels and contributing to the denudation of the land. The whole of this inquiry is eminently suitable for combined research. Each stream or glacier, or each well-marked section of one, might become the special inquiry of a single observer, who would soon develop a paternal interest in his valley and vie with his colleagues of other valleys in the fulness and accuracy of his records. Ner is our information respecting the operations of the sea much more precise. Even in an island like Great Britain, where the waves and tides effect so much change within the space of a human life-time, the estimates of the rate of advance or retreat of the shore-line are based for the most part on no accurate determinations. It is satisfactory to be able to announce that the Council of this Association has formed a committee for the purpose of obtaining full and accurate inform- ation regarding alterations of our coasts, and that with the sanction of the Lords of the Admiralty, the co-operation of the coast-guard throughout the three kingdoms has been secured. We may therefore hope to be eventually in possession of trust- worthy statistics on this interesting subject. The disintegration of the surface of the land by the combined agency of the subaérial forces of decay is a problem which has been much studied, but in regard to whose varying rates of advance not much has been definitely ascertained. The meteorological conditions under which it takes place differ materially according to latitude and climate, and doubtless its progress is equally variable. An obvious and useful source of information in regard to atmospheric denudations is to be found in the decay of the material of buildings of which the time of erection is known, and in dated tombstones. Twenty years ago I called attention to the rate at which marble gives way in such a moist climate as ours, and cited the effects of subaérial waste as these can be measured on the. monuments of our graveyards and cemeteries (Proc. Roy. Soc. Edin., vol. x. 1879-80, p. 518). I would urge upon town geologists, and those in the country NO. 1560, VOL. 60] WATORE | | land. 501 who have no opportunities of venturing far afield, that they may do good service by careful scrutiny of ancient buildings and monuments. In the churchyards they will find much to occupy and interest them, not, however, like Old Mortality, in repair- ing the tombstones, but in tracing the ravages of the weather upon them, and in obtaining definite measures of the rate of their decay. The conditions under which subaérial disintegration is effected in arid climates, and the rate of its advance, are still less known, seeing that most of our information is derived from the chance observations of passing travellers. Yet this branch of the subject is not without importance in relation to the denudation, not only of the existing terrestrial surface, but of the lands of former periods, for there is evidence of more than one arid epoch in geological history. Here, again, a diligent examination of ancient buildings and monuments might afford some, at least, of the required data. In sucha country as Egypt, for instance, it might eventually be possible to determine from a large series- of observations what has been the average rate of surface- disintegration of the various kinds of stone employed in human constructions that have been freely exposed to the air for several: thousand years. Closely linked with the question of denudation is that of the deposition of the material worn away from the surface of the The total amount of sediment laid down must equal the amount of material abstracted, save in so far as the soluble por- tions of that material are retained in solution in the sea. But we have still much to learn as to the conditions, and especially as to the rate, of sedimentation. Nor does there appear to be much hope of any considerable increase to our knowledge until the subject is taken up in earnest as one demanding and justify- ing a prolonged series of well-planned and carefully executed observations. We have yet to discover the different rates of deposit, under the varying conditions in which it is carried on in lakes, estuaries, and the sea. What, for instance, would be a fair average for the rate at which the lakes of each country of Europe are now being silted up? If this rate were ascertained, and if the amount of material already deposited in these basins were determined, we should be in possession of data for estimating, not only the probable time when the lakes will dis- appear, but also the approximate date at which they came into existence. But it is not merely in regard to epigene changes that further more extended and concerted observation is needed. Even among subterranean movements there are some which might be watched and recorded with far more care and continuity than have ever been attempted. The researches of Prof. George Darwin and others have shown how constant are the tremors, minute but measurable, to which the crust of the earth is sub- ject (Report Brit. Assoc., 1882, p. 95). Do these phenomena indicate displacements of the crust, and, if so, what in the lapse of a century is their cumulative effect on the surface of the land ? More momentous in their consequences are the disturbances which traverse mountain-chains and find their most violent expression in shocks of earthquake. . The effects of such shocks have been studied and recorded in many parts of the world, but their cause is still little understood. Are the disturbances due to a continuation of the same operation which at first gave birth to the mountains? Should they be regarded as symptoms of growth or of collapse? Are they accompanied with even the slightest amount of elevation or depression? We cannot tell. But these questions are probably susceptible of some more or less definite answer. It might be possible, for instance, to: determine with extreme precision the heights above a given datum of various fixed points along such a chain as the Alps,. and by a series of minutely accurate measurements to detect any upward or downward deviation from these heights. It is quite conceivable that throughout the whole historical period some deviation of this kind has been going on, though so slowly, or by such slight increments at each period of renewal, as to escape ordinary observation. We might thus learn whether, after an Alpine earthquake, an appreciable difference of level is any- where discoverable, whether the Alps as a great mountain-chain: are still growing or are now subsiding, and we might be able to- ascertain the rate of the movement. Although changes of this nature may have been too slight during human experience to be ordinarily appreciable, their very insignificance seems to me to supply a strong reason why they should be sought for and care- fully measured. They would not tell us, indeed, whether a mountain-chain was called into being in one gigantic convulsion, 502 NATURE [SEPTEMBER 21, 1899 ‘or was raised at wide intervals by successive uplifts, or was slowly elevated by one prolonged and continuous movement. But they might furnish us with suggestive information as to the vate at which upheaval or depression of the terrestrial crust is now going on. The vexed questions of the origin of raised beaches and sunk Forests might in like manner be elucidated by well-devised measurements. It is astonishing upon what loose and untrust- worthy evidence the elevation or depression of coast-lines has often been asserted. On shores where proofs of a recent change of level are observable it would not be difficult to establish by accurate observation whether any such movements are taking place now, and, if they are, to determine their rate. The old attempts of this kind along the coasts of Scandinavia might be resumed with far more precision and on a much more extended scale. Methods of instrumental research have been vastly improved since the days of Celsius and Linnzus. Mere eye-observations would not supply sufficiently accurate results. When the datum-line has been determined with rigorous accuracy, the minutest changes of level, such as would be wholly inappreciable to the senses, might be detected and recorded. If such a system of watch were maintained along coasts where there is reason to believe that some rise or fall of land is taking place, it would be possible to follow the progress of the movement and to determine its xate. But I must not dwell longer on examples of the advantages which geology would gain from a far more general and sys- tematic adoption of methods of experiment and measurement in elucidation of the problems of the science. I have referred toa few of those which have a more special bearing on the question of geological time, but it is obvious that the same methods might be extended into almost every branch of geological dynamics. While we gladly and gratefully recognise the large amount of admirable work that has already been done by the adoption of these practical methods, from the time of Hall, the founder of experimental geology, down to our own day, we cannot but feel that cur very appreciation of the gain which the science has thus derived increases the desire to see the practice still further multiplied and extended. I am confident that it is in this direction more than in any other that the next great advances of geology are to be anticipated. While much may be done by individual students, it is less to their single efforts than to the combined investigations of many fellow-workers that I look most hopefully for the ac- cumulation of data towards the determination of the present rate of geological changes. I would therefore commend this subject to the geologists of this and other countries as one in which individual, national and international co-operation might well be enlisted. We already possess an institution which seems well adapted to undertake and control an enterprise of the kind suggested. The International Geological Congress, which brings together our associates from all parts of the globe, would confer a lasting benefit on the science if it could organise a system of combined observation in any single one of the departments of inquiry which I have indicated or in any other which might be selected. We need not at first be too ambitious. The simplest, easiest and least costly series of ob- servations might be chosen for a beginning. The work might be distributed among the different countries represented in the Congress. Each nation would be entirely free in its selection of subjects for investigation, and would have the stimulus of co-operation with other nations in its work. The Congress will hold its triennial gathering next year in Paris, and if such an organisation of research as I have suggested could then be inaugurated a great. impetus would thereby be given to geo- logical research, and France, again become the birthplace of another scientific movement, would acquire a fresh claim to the admiration and gratitude of geologists in every part of the globe. ; SECTION D. ZOOLOGY. OPENING ADDRESS BY ADAM SEDGWICK, PRESIDENT OF THE SECTION. M.A., F.R-S., Variation and some Phenomena connected with Reproduction and Sex. IN the following Address an attempt is made to treat the facts of variation and heredity without any theoretical preconceptions. The ground covered has already been made familiar to us by NO. 1560, VOL. 60| the writings of Darwin, Spencer, Galton, Weismann, Romanes and others. I have not thought it advisable to discuss the theories of my predecessors, not from a want of appreciation of their value, but because I was anxious to look at the facts them- selves and to submit them to an examination which should be as free as possible from all theoretical bias. Zoology is the science which deals with animals. Knowledge regarding animals is, for convenience of study, classified into several main branches, amongst the most important of which may be mentioned : (1) the study of structure ; (2) the study of the functions of the parts or organs; (3) the arrangement of animals in a system of classification; (4) the past history of animals; (5) the relations of animals to their environment ; (6) the distribution of animals on the earth’s surface. That part of the science of zoology which deals with the functions of organs, particularly of the organs of the higher animals, is fre- quently spoken of as physiology, and separated more or less sharply from the rest of zoology under that heading. So strong is the line of cleavage between the work of the physiologist and that of other zoologists, that this Association has thought it ad- visable to establish a special Section for the discussion of physiological subjects, leaving the rest of zoology to the con- sideration of the old established Section, D. In calling attention to this fact, I do not for one moment wish to question the advisability of the course of action which the As-ociation has taken. The science of physiology in its modern aspects includes a vast body of facts of great importance and great interest which no doubt require separate treatment. But what I do wish to point out is that it is quite impossible for us here to abrogate all our functions as physiologists | Some of the most important problems of the physiological side of zoology still remain within the purview of this Section. For instance, the important and far-reaching problems con- nected with reproduction and variation are very largely left to this Section, and that large group of intricate and almost en- tirely physiological phenomena connected with the’ adaptations of organisms to their environment are dealt with almost ex- clusively here. Indeed, we may go further, and say that apart altogether from practical questions of convenience, which make it desirable to separate a part of physiological work from the Zoological Section, it is, as a matter of fact, impossible to divorce the intelligent study of structure from that of function. The two are indissolubly connected together. The differ- entiation of structure involves the differentiation of function, and the differentiation of function that of structure. The con- ceptions of structure and function are as closely associated as those of matter and force. A zoologist who confined: himself to the study of the structure of organisms, and paid no atten- tion to the functions of the parts, would be as absurd a person as a philologist who studied the structure of words and took no account of their meaning. In the early part of this century, when the subject-matter of zoology was not so vast as it is at present, this aspect of the case was fully recognised, and one of the greatest zoologists of the century, whether considered from the point of view of modern anatomy, or of modern physiology, was Professor of Anatomy and Physiology at the University of Berlin. Having said that much as to the various aspects of living nature, of natural history, if you like, which it falls within the province of this Section to deal with, I may now proceed to the subject of my address. And when I mention to you what that subject is, you will be able to make some allowance for the somewhat commonplace remarks with which I have treated you. For that subject, though it has its important morphological aspects, is in the main a physiological one; at any rate, no study which does not take account of the ‘physio- logical aspect of it can ever hope to satisfy the intellect of man. The subject, then, to which I wish to draw your attention at the outset of our proceedings, is the great subject of Variation of Organisms. : : As every one knows, there is a vast number of different kinds of organisms. Each kind constitutes a species, and consists of an assemblage of individuals which resemble one another more closely than they do other animals, which transmit their characteristics in reproduction and which habitually live and breed together. But the members of a species, though re- sembling one another more closely’ than they resemble the members of other species, are not -absolutely alike. They pre- sent differences, differences which make themselves apparent SEPTEMBER 21, 1899 | even in members of the same family, z.e. in the offspring of the same parents. It is these differences to which we apply the term variatzen. The immense importance of the study of variations may be judged from the fact that, according to the generally received evolution theory of Darwin, it is to them that the whole of the variety of living and extinct organisms is due. Without variation there could have been no progress, no volution in the structure of organisms. If offspring had always exactly resembled their parents and presented no points of difference, each succeeding generation would have resembled those previously existing, and no change, whether backwards or forwards, could have occurred. This phenomenon of genetic wariation forms the bedrock upon which all theories of evolution must rest, and it is only bya study of variations, of their nature and cause, that we can ever hope to obtain any real insight into the actual way in which evolution has taken place. Notwith- standing its importance, the subject is one which has scarcely received from zoologists the attention which it merits. Though much has been written on the causes of variation, too little attention has of late years been paid to the phznomenon. Since the publication of Darwin's great work on the ‘* Variation of Animals and Plants under Domestication,” there have been but few books of first-rate importance dealing with the subject. The most important of these is Mr. William Bateson’s work, entitled ‘* Materials for the Study of Variation.” I have no hesitation in saying that I regard this work as a most important contribution to the literature of the evolution theory. In it at- tention is called, with that emphasis which the subject demands, to the supreme importance of the actual study of variation to the evolutionist, and a systematic attempt is made to classify vari- ations as they occur in nature. In preparing this book Mr. Bateson has performed a very real service to zoology, not the least part of which is that he has made a most effective protest against that looseness of speculative reasoning which, since the publication of the ‘‘ Origin of Species,” has marred the pages of so many zoological writers. ‘The variations of organisms may be grouped under two heads, according to their nature and source: (1) There are those vari- ations which appear to have no relation to the external condi- tions, for they take place when these remain unchanged, e.g. in members of the same litter ; they are inherent in the constitution of the individual. These we shall call constitutional variations, or as their appearance seems nearly always to be connected with reproduction, they may be called geve/zc (congenital, blastogenic) zariations. (2) The second kind of variations are those which are caused by the direct action of external conditions. These variations constitute the so-called acguéred characters. My first object is to consider these two kinds of variations, their nature, their causes, and their results on subsequent gener- ations, and te inquire whether there are any fundamental differences between them. In this connection it is of particular importance that we should inquire whether acquired modifi- cations are transmitted in reproduction. As is well known, there are two schools of thought holding directly opposite views as to this matter. The one of these schools—the so-called Lamarckian school—holds that they may be transmitted as such in reproduc- tion; the other school, on the other hand, maintains that acquired modifications affect only the individual concerned, and are not handed on as such in reproduction. That the decision of the matter is not only theoretically important, but also practically, is evident, for upon it depends the answer to the question whether mental or other facilities acquired by the Jaborious exercise of the individual are ever transmitted to the offspring—whether the facility which the individual acquires in eesisting temptation makes it any easier for the offspring to do the same, whether the effects of education are cumulative in successive generations. To put the matter as Francis Galton has put it, Is nature stronger than nurture, or nurture than nature ? We have then two kinds of variation to consider: (1) genetic wariation, (2) acquired modification. It is the former of these— namely, genetic variation—with which I wish primarily to deal. Let us examine more fully the mode of its occurrence. Genetic Variation. Organised beings present, as you are aware, two main kinds of reproduction, the sexual and the asexual.. These two kinds of reproduction present certain differences, of which the most important, and the only one which concerns us now, is- the fact that genetic variation is essentially associated with sexual repro- NO. 1560, VOL. 60] NATURE 593 duction, and is rarely, if ever, found in asexual reproduction. In other words, whereas the offspring resulting from asexual re- production as a rule exactly resemble the pirent, they are always different from the parents in sexual reproduction. I am aware that I am treading on disputed ground. You will observe that I do not make the assertion that asexually produced offspring always exactly resemble the parent, and never present genetic variations. To say that would be going to» far in the present state of our knowledge. Therefore [ have put the matter less strongly, and merely assert that whereas asexual reproduction is on the whole characterised by identity between the offspring and the parent, sexual reproduction is al ways characterised by differ- ences more or less marked between the two; and I reserve the question as to whether genetic variations are ever found in asexual reproduction for later consideration. This modified form of the statement will, I think, be admitted on all hands, but before going on I will illustrate my meaning by reference to actual examples. Asexual reproduction is a phenomenon comparatively rare in the animal kingdom, and when it does occur it is exceedingly difficult to investigate from this particular point of view. In the vegetable kindom, on the other hand, it is quite common. All, or almost all, plants possess this power, and in a very great many of them the result of its exercise can be fully followed out, and contrasted with that of sexual reproduction. Let us follow it out in the potato-plant. The potato can and does normally propagate itself asexually by means of its underground tubers. As you will know, if you take one of these and plant it, it gives rise to a plant exactly resembling the parent. If the tuber (seed as it is sometimes erroneously called) be that of the Magnum Bonun, it gives rise to a plant with foliage, flowers and tubers of the Magnum Bonum variety ; if it be of the Snowdrop, the foliage, flowers, habit and tubers are totally different from the Magnum Bonum, and are easily identified as Snowdrops. In this way a favourable variety of potato can be reproduced to almost any extent with all its peculiarities of earliness or late- ness, pastiness or mealiness, power of resisting disease and so forth. By asexual reproduction the exact facsimile of the parent may always be obtained, provided the conditions remain the same. Now let us turn to the results of sexual reproduction—the seeds, z.e. the real seeds, which as you know are produced in the flowers, are the means by which sexual reproduction is effected. They are produced in great quantity by most plants, and when placed in the ground under the proper conditions they germinate and produce plants. But these plants do not resemble the parent. Try the seed of the Magnum Bonum potato, and raise plants from it. Do you think that any of them will be the Magnum Bonum with all its properties of keeping, resisting disease, and so forth? Nota bit of it. The probability is, that not one of your seedling plants will exactly reproduce the parents; they will all be different. Again, take the apple; if you sow the seed of the Blenheim Orange and raise young apple-trees, you will not get a Blenheim Orange. © All your plants will be different, and probably not one will give you apples with the peculiar excellence of the parent. If you want to propagate your Blenheim Orange and increase the number of your trees, you must proceed by grafting or by striking cuttings, which are the methods by which such a tree may be asex- ually reproduced. And so on. Examples might be multiplied indefinitely. Every horticulturist knows that variety characterises seedlings, ¢.e. sexual offspring, whereas identity is found-in slips, grafts and offsets, ¢.¢. in asexual offspring ; and that if you want to get a new plant you must sow seeds, while if you want to increase your stock of an old one you must strike cuttings, plant tubers or proceed in some analogous manner. An apparent exception to this rule is afforded by so-called bud variation, but it is not certain that this is really an exception. In so far as these bud variations are not of the nature of acquired variations produced by a change of external conditions, and disappearing as soon as the old conditions are renewed, they are probably stages in the growth and development of the organism. That is to say, they are of the same nature as those peculiarities in animals which appear at a particular time of life, such as a single lock of hair of a different colour from the rest of the hair,! the change in colour of hair with growth,” the appearance of insanity or of epilepsy at a particularage. There 1 Darwin, ‘ Variation,” vol. i. p. 449. x ! } 2 Asan example I may refer to the Himalayan rabbit ; Darwin, “‘ Varia- tion,” vol. i. p. 114. : 504 NATORE [SEPTEMBER 21, 1899 is nothing more remarkable in a single bud on a tree departing from the usual character at a particular time of life, than in a particular hair ofa mammal doing the same thing. We have seen that, speaking broadly, genetic variation is connected with sexual reproduction, and it becomes necessary to examine this mode of reproduction a little more fully. What is the essence of sexual reproduction, and how does it differ from asexual ? What I am now going to say applies generally to the phenomenon whether it occurs in plants or animals. Sexual re- production is generally carried on by the co-operation of two distinct individuals—these are called the male and female respectively. They produce, by a process of unequal fission which takes place at a part of their body called the reproductive gland, a small living organism called the reproductive cell. The reproductive cell produced by the male is called in animals the spermatozoon, and is different in form from the corresponding cell produced by the female, and called in animals the ovum. The object with which these two organisms are produced is to fuse with one another and give rise to one resultant uninucleated organism or cell, which we may call the zygote. This process of fusion between the two kinds of reproductive cells, which are termed gavie’es, is called conjugation. The difference in struc- ture between the male and female gamete is a matter of secondary importance only, and isconnected with the primary function of coming into contact and fusing. The same may be said with regard to the so-called sexual differences of the parents of the two kinds of gametes, and to the powerful instincts which regulate their action. The conjugation of the male and female gamete, or the fertilisation of the ovum, as it is sometimes called, consists in the fusion of two distinct masses of protoplasm which are nearly always produced by different individuals. In the case of hermaphrodites, the term applied to organisms which produce both male and female gametes in the same individual, there is generally some arrangement which tends to prevent the male gamete from conjugating with the female gamete of the same parent ; but this phenomenon is not absolutely excluded, and takes place as a normal phenomenon in many plants and possibly in some animals. This fusion of the protoplasm of the two gametes gives us a uninucleated organism—for the fusion of the nuclei of the two gametes seems to be an essential part of the process—in which the potencies of the two gametes are blended. The zygote, as the mass formed of the fused gametes is called, is formed by the combination of two individualities, and is therefore essentially a new individuality, the characters of which will be different from the characters of both of the parents. This fact, which is not apparent in the zygote when first established, because the parts are hardly distinguishable by our senses, becomes obvious as soon as organs, with the appearance of which we are familiar, are formed. As a general rule this cannot be said to have occurred until what we call maturity has been nearly reached, because we are not familiar enough with the features of im- mature organisms to detect individual differences. But you may rest assured that such differences exist at all stages of growth from that of the uninucleated zygote till death. How the characters of the two parents will combine in the zygote it is impossible to predict, and the result is never the same even though the conjugations have been between gametes of identical origin. There may be an almost perfect mixture, the blending extending to even quite minute details ; or the characters of the one parent may predominate—be pre- potent, as we call it—over those of the other; or they may blend in such a way that the zygote offers characters found in neither parent. Or, finally, the features of one parent may come out at one stage of growth, those of the other at another stage. But, however the characters may blend, the product never exactly resembles the parents. The extent to which it differs from them is the measure of the variation. To resume, it will be observed that in the method of repro- duction sometimes called sexual two distinct processes occur. One of these is the real reproductive act, which consists in the production by fission of uninuclear individuals called gametes ; the second is the fusion of the gametes to form the zygote. The gametes are of two kinds, and the reason of there being two kinds is intelligible when we consider the parts they have to play. The male gamete is nearly always endowed with loco- motive power, and the female gamete is stored with food material to be used by the zygote in the first stages of growth. The destiny of these two uninucleated organisms is to fuse with one another, and so to give rise to a zygote which ultimately NO. 1560, VOL. 60} assumes the typical form of the species. As a general rule, the gametes have but a limited duration? of life unless they con- jJugate, and this is quite intelligible when we remember that they have no organs, e.g. digestive organs, suitable for the maintenance of life. It is rarely found that they have the power of assuming the form of their parent, unless they conjugate. This never happens in the case of the male gamete (at any rate in animals), and only rarely in that of the female. When it occurs—that is to say, when the ovum develops without con- jugation—we call the phenomenon parthenogenesis. genesis is found more commonly in Arthropods than in other groups, but it may be more common than is supposed.” In sexual reproduction then, in addition to the real reproduc- tive act, which is the division by fission of the parent into two unequal parts, the one of which continues to be called the parent, while the other is the gamete, there is the subsequent conjugation process. It is to this conjugation process that that important concomitant of sexual reproduction must be attributed, namely, genetic variation. We have thus traced genetic variation to its lair. We have seen that it is due to the formation of a new individuality by the fusion of two distinct individualities. We have also seen that in the higher animals it is always associated with the reproductive act. Let us now take a wider survey and endeavour to ascertain whether this most important process, a process upon which depends the improvement as well as the degradation of races, ever takes place independently of the reproductive act. In the Metazoa, to which for our present purpose I allude under the term higher animals, conjugation never takes place except in connection with reproduction. It is impossible from the nature of the process that it should do so, as I hope to explain later on. But among the Protozoa, the simplest of all animals, it is con- ceivable that conjugation might take place apart from reproduc- tion, and asa matter of fact itdoes doso. Let us now examinea case in which this occurs. Amongst the free-swimming ciliated Infusoria it frequently happens that two individuals become applied together, and that the protoplasm of their bodies becomes continuous. They remain in this condition of fusion for some days, retaining, however, their external form and not undergoing complete fusion. While the continuity lasts there is an exchange of living substance between the two bodies, in which exchange a bit of the nucleus of each participates. It thus happens that at the end of conjugation, when the two animals separate, they are both different from what they were at the commencement each has received protoplasm and a nucleus from its fellow, and the introduced nucleus fuses as we know with the nucleus which has not moved. It would therefore appear that all the essential features of the conjugation process, as we learnt them in the case of the conjugation of the gametes in the Metazoa, are present, and it is impossible to doubt that we have here an essentially similar phenomenon. The phenomenon differs, however, from the conjugation first described in this interesting and important respect, that the two animals separate and resume their ordinary life. It is true that their constitution must have been profoundly changed, but they retain their general form. I say that the constitution of the exconjugates, as we may call them after they are separated, must be different from what it was before conjugation, but so far as I know no difference in structure corresponding with this difference in con- stitution has been recorded. I feel no sort of doubt, however, that structural differences, z.e. variations, will be detected when the exconjugates are closely scrutinised and compared with the, animals before conjugation, and I would suggest that definite observations be made with a view to testing the point. Here, then, we have a case of conjugation entirely dissociated from reproduction, Other cases of a similar character are known among the Protozoa, though as a general rule the fusion between the conjugating organisms is complete and permanent. Among plants conjugation is generally associated with reproduction, but not always, tor in certain fungi? fusion of hyphze and consequent intermingling of protoplasm occurs, and is not followed by any 1 Under favourable conditions, they may live a considerable time—e.g. the spermatozoon of certain ants, which are stated by Sir John Lubbock to live in some cases for seven years. 2 It may be mentioned as a curious fact that parthenogenesis is rarely found in the higher plants, and, as I have said, is not known for the male gamete among animals. 3 It must be mentioned, however, that in the case of these fungi the fusion of nuclei has not been observed, nor has it been noticed whether the habit, structure, or constitution of the conjugating plants are altered after the fusion. Partheno- — —a SEPTEMBER 21, 1899] form of reproduction. Among bacteria alone, so far as I know, has the phenomenon of conjugation never been observed. To sum up, we have seen that the phenomenon of conjuga- tion is very widely distributed. Excluding the bacteria, there is reason to believe that it forms a part of the vital phenomena of all organisms. Its essential features are a mixture and fusion of the protoplasm of two different organisms, accompanied by a fusion of their nuclei. It results in the formation of a new individuality, which differs from the individualities of both the conjugating organisms. This difference manifests itself in differences in habit, constitution, form, and structure, such differences constituting what we have called genetic variations. The conjugation of the ovum and spermatozoon in the higher animals, and the corresponding process in the higher plants, are special cases of this conjugation, in which special conjugating individuals are produced, the ordinary individuals being physi- cally incapable of the process. The phenomenon of sex, with all its associated complications, which is so characteristic of the higher animals and plants, is merely a device to ensure the coming together of the two gametes. In the lower animals, it is possible for the ordinary organism to conjugate; consequently the phenomenon does not form the precursor of developmental change, and is in no way associated with reproduction. Indeed, in such cases it is often the opposite of reproduction, inasmuch as it brings about a reduction in the number of individuals, two Separate individuals fusing to form one. Acquired Characters. We now come to the consideration of the second kind of variations—namely, those which owe their origin to the direct action of external agencies upon the particular organism which shows the variation ; or, as Darwin puts it, to the definite action of external conditions. These are the variations which I have called acquired variations or acquired characters. This is not a good name for them, but at the present moment, when I am about to submit them to a critical examination, I do not know of any other which could be suitably applied. Later on, when T sum up the various effects of the direct action of external agencies upon the organism, I may be able to use a more suitable term. The main peculiarities of acquired variations are two in number ; (2) they make their appearance as soon as the organism is submitted to the changed conditions ; (4) speaking generally, they are more or less the same in all the individuals of the species acted upon. As examples of this kind of variations, I may mention the effect of the sun upen the skin of the white man ; the Porto Santo rabbit, an individual of which recovered the proper colour of its fur in four years under the English climate ;1 the change of Artemia salina to Artemia milhausenit ; the increase in size of muscles as the result of exercise ; and the development of any special facility in the central nervous system. Among plants, variations of this kind are very easily acquired, by altering the soil and climate to which the individuals are submitted. So common are they, that it is quite possible that a large number of species are really based upon characters of this kind; characters which are produced solely by the external conditions, and which frequently disappear when the old conditions are reverted to. With regard to these variations, we want to ask the following question: Do they ever last after the producing cause of them is removed, and are they transmitted in reproduction? Ina great number of cases they either cease when the cause which has pro- duced them is removed, or if they last the life of the individual they are not transmitted in reproduction. But is this always the case? That is the important question we now have to consider. But before doing so let us inquire what acquired characters really are. The so-called adults of all animals have, as part of their birthright, a certain plasticity in their capacity of reacting to external influences ; they all have a certain power of acquiring bodily and mental characters under the influence of appropriate stimuli. This power varies in degree and in quality in different species. In plants, for instance, it is mainly displayed in habit of growth, form of foliage, &c.; in man, in mental acquire- ments, and so on. But however it is displayed, it is this pro- perty of organisms which permits of the acquisition of those modifications of structure which have been so widely discussed as acguiyed characters. Now this power, when closely con- 1 Darwin, ‘‘ Variation,” ed. 2, vol. i, p. 119. NO. 1560, VOL. 60] NATURE 505 sidered, is in reality only a portion of that capacity for develop- ment which all organisms possess, and with which they become endowed at the act of conjugation. A newly formed zygote pos- sesses a certain number of hidden properties which are not able to manifest themselves unless it is submitted to certain external stimuli. It is these stimuli which constitute the external condi- tions of existence, and the properties of the organism which are only displayed under their influence are what we call acquired characters. They are acquired in response to the external stimuli. It would appear, then, that every feature which successively appears in an organism in the march from the uninucleated zygote to death is an acquired character. At first the stimuli which are necessary are quite simple, being little more than ap- propriate heat and moisture ; ]ater on they become more com- plicated, until finally, when the developmental period is over and the mature life begins, the necessary conditions attain their greatest complexity, and their fulfilment constitutes what we call in the higher animals education. Education is nothing more than the response of the nearly mature organism to ex- ternal stimuli, the penultimate response of the zygote to ex- ternal stimuli, the ultimate being those of senile decay, which end in natural death, Acquired properties, it will be seen, are really stages in the developmental history. They differ in the complexity of the stimulus required to bring them out. For instance, the segmentation of the egg requires little more than heat and moisture, the walking of the chick the stimulus of light and sound and gravity, the evolutions of an acrobat the same in greater complexity, and, lastly, the action of a statesman requires the stimulation of almost every sense in the greatest complexity. Moreover, not only are there differences in the complexity of the stimulus required, but also in the rapidity with which the organism reacts to it. The chick undergoes its whole embryonic development in three weeks, a man in nine months; the chick develops its walking mechanism in a few minutes, while a man requires twelve months or more to effect the same end. Chickens are much cleverer than human beings in this respect. There is the same kind of difference between them that there is between the power of learning displayed by a Macaulay and that displayed by a stupid child. An instinct is nothing more than an internal mechanism which is developed with great rapidity in response to an appropriate stimulus. It is difficult for us to understand instincts, because with us almost all developmental processes are extremely slow and gradual, This particularly applies to the development of those nervous mechanisms, the working of which we call reason, Within certain limits the external conditions may vary without harming the organism, but such variations are generally accom- panied by variations in the form in which the properties of the zygote are displayed. If the variations of the conditions are too great, their action upon the organism is injurious, and results in abortions or death. And in no case can the external conditions call out properties with which the zygote was not endowed at the act of conjugation. It would thus appear that acquired characters are merely phases of development ; they are the manifestations of the pro- perties of the zygote, andare called forth only under appropriate stimulation ; moreover, they are capable of varying within certain limits, according to the nature of the stimulus, and it is to these variations that the term acquired character has been ordinarily applied, 2h A genetic character, on the other hand, is the possibility of acquiring a certain feature under the influence of a certain stimulus ; it is not the feature itself—that is an acquired character —but it is the possibility of producing the feature. Now as the possibility of producing the feature can only be proved to exist by actually producing it, the term genetic character is frequently applied to the feature itself, which is, as we have seen, an acquired character. In consequence of this fact, that we can only determine genetic characters by examining acquired char- acters, a certain amount of confusion may easily arise, and has indeed often arisen, in dealing with this subject. This can be avoided by remembering that in describing genetic characters account must always be taken of the conditions. For example, the white fur of the Arctic hare is an acquired character, acquired in response to a certain stimulus ; while the power of so responding to the particular stimulus when applied at the cor- rect time is a genetic character. Thus a genetic character is a character which depends upon the nature of the organism, 506 NATURE [SEPTEMBER 21, 1899 hile an acquired character depends on the nature of the stimulus. If we imagine a zygote to be a machine capable of working out certain results on material supplied to it, then we should properly apply the term genetic character to the features of the machinery itself, and the words acquired character to the results achieved by its working. These clearly will depend primarily on the structure of the machinery, and secondarily upon the material and energy supplied to it—that is to say, upon the way in which it is worked. Variations in genetic characters are variations in the machinery of different zygotes—that is to say, in the constitu- tion—while variations in acquired characters are variations in the results of the working of one zygote according to the con- ditions under which it is worked. For instance, let us take the case of those twins which arise by the division of one zygote, and are consequently identical in genetic characters, z.e. in constitution. If they are submitted to different conditions, they will develop differences which will depend entirely upon the conditions and the time of life when the differentiation in the conditions occurred. These differences, then, will be a function of the external conditions, z.e. of the manner in which the machinery is worked, and constitute what we call variation in acquired characters. Are Acquired Characters Transmissible as such in Reproduction ? To return to our question, are the so-called acquired char- acters ever transmitted in reproduction? Let us consider what this question means in the light of the preceding discussion. Acquired characters are features which arise in the zygote in response to external stimuli. Now the zygote at its first estab- lishment has none of the characters which are subsequently acquired. All it has is the power of acquiring them. Clearly, then, acquired characters are not transmitted. The power of producing them is all that can be transmitted ; and this power resides in the reproductive organs and in the gametes to which the reproductive organs give rise, so that the question must be put in another form, Is it possible by submitting an organism toa certain set of conditions, and thus causing it to acquire certain characters, so to modify its reproductive organs that the same characters will appear in its offspring as the result of the application of a different and simpler stimulus ? For instance, the power of reading conferred by education, the hardness of the hands and increased size of the muscles pro- duced by manual labour: is it possible that these characters, now produced by complex external stimuli applied at a particular period of life, should ever in future ages be produced by the simpler stimuli found within the uterus, so that a man may be born able to read or write, or with hands horny and hard like those of a navvy ? In trying to find an answer to this question let us first of all look into the probabilities of the case, to see if we can relate the question to any other class of phenomena about which we have, or think we have, definite knowledge. When an organism is affected by external agents the action may apply to the whole organisation or principally to one organ. Let us take a case in which one organ only appears to be affected, ¢.¢. the enlargement by exercise of the right arm of a man. Now, although in this case it is only the muscles of the arm which appear at first sight to be affected, we must not forget that the organs of the body are correlated with one another, and an alteration of one will produce an alteration in others. By exercise of the right arm the muscles of that arm are obviously enlarged, but other changes not so obvious must also have taken place. The bones to which the muscles are attached will be altered ; the blood-vessels supplying the muscles will be en- larged, and the nerves which act upon the muscles, and probably the part of the central nervous system from which they proceed, will also be altered. These are some of the more obvious cor- related changes which will have occurred ; no doubt there will have been others—indeed it is not perhaps too much to say that all the organs of the body will have reacted to the enlargement of the arm—but the effect on organs not in functional correla- tion with the muscles of the right arm will be imperceptible, and may be neglected. Thus the colour of the hair, the length and character of the alimentary canal, size of the leg muscles, the renal organs, &c., will not show appreciable alteration. Above all, the other arm will not be affected, or if it is affected the alteration will be so slight as not to be noticeable. Now, NO. 1560, VOL. 60] we know that homologous parts, whether symmetrically homo- logous or serially so, are in some kind of close connection. For instance, when one member of an homologous series varies, it is commonly found that other members of the same series will also vary. Yet in spite of this connection which exists between the right and left arms and between the right arm and right leg, there is no similar alteration either in the left arm or in the right leg. Now, if parts which from these facts we may suppose to be in some connection are not affected, how can we expect the reproductive organs, not only to be modified, but also to be so modified that the germs which are about to be budded off from them will be so affected as to produce exactly the same char- acter—in this case enlarged muscle, &c.—without the applic- ation of the same stimulus, viz. exercise? Thus, while I freely admit that every alteration of an organ in response to externa) agents wlll react through the whole organisation, affecting each organ in functional correlation with the affected organ in a way which will depend upon the function of the correlated organ, and possibly other organs not in functional correlation in an in- definite way and to a slight extent, yet I maintain that it is very hard to believe that it will have such a sharp and precise effect upon every spermatozoon and ovum subsequently produced that not merely will these products be altered generally in all their properties, but that one particular part of them—and that part of them always the same—will be so altered that the organisms which develop from them will be able to present the same modification on the application of a different stimulus. It is in- conceivable ; unless, indeed, we suppose that the very mole- cules of the incipient organs in the germ are more closely cor- related with corresponding parts of the parent body than are the homologous parts of the parent body with one another. Now, to prove the existence of such a remarkable and inti- mate correlation would surely require the very strongest and most conclusive evidence. Is there any such strong evidence ? I think I may fairly answer this question in the negative. The evidence which has been brought forward in favour of the so- called inheritance of acquired characters is far from conclusive. That such evidence! exists I do not deny, but it is all, or almost all, capable of receiving other interpretations. Effect of Changed Conditions upon the Reproductive Organs. On the other hand, all the certain evidence we have concern- ing what happens when the reproductive organs are affected, either directly or by correlation, by a change of conditions— and, as we have seen above, they must be affected if there is to be any change in the offspring—tends to show that there is not any relation between the effect produced on the parent and that appearing in the offspring. The only means of judging whether the reproductive organs are affected by external conditions is by observing any change which may occur in their function. Now, only two such physiological effects of a change of conditions are certainly known; these are (1) the production of sterility or of partial sterility ; (2) the production of an increased but indefinite vari- ability in the offspring. With regard to the first of these effects One of the most common, or at any rate one of the most notice- able, alterations in an organism, effected by change in the external conditions, is an alteration of the reproductive system, an alterationof such a kind that organisms which had previously freely interbred with one another are no longer able to do so. One of the most common results of removing organisms from their natural surroundings is to induce sterility or partial sterility. There is no reason to doubt that this sterility or tendency to sterility is, broadly speaking, due to an affection of the repro- ductive system. In the case of the higher animals, it may in some cases be due to an action upon the instincts, but in the lower animals and in plants we can hardly doubt that it is due to a direct action upon the reproductive organs. Indeed in plants these organs are often visibly affected. Among animals, however, there does not appear to be any satisfactory evidence on the point, and it is not known what organs are affected, whether it is the actual gametes, or the reproductive glands, or some of the other organs concerned.” The other result of changed conditions which is certainly known is to induce an increased amount of variability of the genetic kind, though not immediately, often indeed not untib 1 For a good statement and discussion of the evidence in favour of this. view, see Romanes’ * Darwin and after Darwin,” vol. ii. chaps. 3 and 4. 2 The exact cause of this sterility in the higher animals is a point which specially needs investigation. SErTEMBER 21, 1899] NATORE 597 after the lapse of some generations. On this point Darwin says: “‘ Universal experience shows us that when new flowers are first introduced into our gardens they do not vary; but ultimately all, with the rarest exceptions, vary to a greater or less extent” (‘* Variation,” 2, p. 249)! With regard to the variability thus induced, it is to be noticed that it is not confined to any particular organ, nor does it show itself in any particular way. On the contrary, the whole organisation is affected, and the variations are quite indefinite. To sum up the argument as it at present stands: (1) a change in conditions cannot affect the next generation unless the repro- ductive organs are affected ; (2) from a consideration of the facts of the case, it is almost inconceivable that the effect produced upon any organ of a given organism by a change of conditions should so modify the reproductive organs of that organism as to lead to a corresponding modification in the offspring without the latter being exposed to the same conditions ; (3) the only effects, which are certainly known, of changed conditions upon the reproductive organs are (a) the production of sterility ; (4) an increase in genetic variability. As far, then, as our certain knowledge goes, it would appear that a change of conditions may have one or both of the following effects :— (1) A definite change, of the same character, or nearly so, in all the individuals acted upon. Such changes may be adaplive or non-adaptive, but they are not permanent, lasting only so long as the change of conditions, or at most during the life of the individual acted upon. They are not transmitted in repro- duction, and do not appear in the offspring unless it is sub- mitted to the same conditions. These variations are the direct result of the action of the environment upon the individual, with the exception of the reproductive organs. (2) Increase in the variations of the genetic kind These are seen, not in the generation ? first submitted to the changed con- dition, but in the next or some subsequent generations. The effect is produced through the reproductive organs. These variations are non-adaptive, and different in each individual. If the reproductive organs are affected we get an increase in the variations of the genetic kind. These, we have seen, are usually of an indefinite character ; they are different in every case, and their nature cannot be predicted from experience. But we still have to ask: Is this is a universal rule? Does it never happen that a change of conditions so affects the reproductive organs as to produce a definite non-adaptive change of the same character or nearly so in all the descendants of the individual acted upon? This is the most obscure question connected with the study of variations. If such changes occur, they might be cumulative, being increased in amount by the continued action of the conditions. They would be non-adaptive, their nature depending on the constitution of the reproductive cells and having no functional relation to the original stimulus. As possible examples of such variation, I may recall those variations referred to by Darwin as ‘fluctuating variations which sooner or later become constant through the nature of the organism and of surrounding conditions, but not through natural selection” (‘ Origin,’ ed. 6, p. 176); to the variations in turkeys and ducks which take place as the result of domestic- ation (‘‘ Variation,” 2, p. 250); to those variations which Darwin had in his mind when he wrote the following sentence (‘* Origin,” p. 72): ‘‘There can be little doubt that the tendency to vary in the same manner has often been so strong that all the individuals of the same species have been similarly modified without the aid of selection.” It is, however, as I have said, extremely doubtful if vari- ations of this kind really occur. The appearance of them may be caused by the combination of the two other kinds of vari- ation. In all cases which might be cited in support of their occurrence, there are the following doubtful elements: (1) no clear statement as to whether the variations showed themselves in the individuals first acted upon; (2) no history of the organisms when transported back to the old conditions. 1 The phenomenon of increased variability following upon change or con- ditions has most often been observed when the change has been from a state of nature to a state of cultivation. Hence the conclusion has been drawn that the kind of change involved in domestication alone induces variation. But there is no evidence in favour of this view. The evidence shows that change of conditions in itself may induce greater variability. 2 No doubt the individuals of the generation first submitted to the changed conditions would be affected as regards their reproductive organs, which would be altered in structure, but this has not been made out, though there are indications of such an effect in certain plants, vide Appendix. NO. 1560, VOL. 60] Moreover, a general consideration of the facts of the case renders it improbable that such similar and definite genetic variations should ofien occur at any rate in sexual reproduction. For although the effect upon the reproductive organs may pos- sibly be almost the same in nearly all the individuals acted upon, it must not be forgotten that the reproductive elements have to combine in the act of conjugation, and that it is the essence of this act to produce products which differ in every case. Effect of Changed Conditions in Asexual Reproduction. This brings us to the consideration of the question reserved on p- 503: Are genetic variations ever found in asexual reproduc- tion? If the views expressed in the earlier part of this address are correct, it would seem to follow that genetic variations are variations in the actual constitution, and are inseparably connected with the act of conjugation. The act of conjugation gives us a new constitution, a new individuality, and it is the characters of this new individual in so far as they differ from the characters of the parents which constitute what we have called genetic variations. According to this, the answer to our question would be that genetic variations cannot occur in asexual reproduction, and that if any indefinite variability recalling genetic variability makes its appearance! it must be part of the genetic variability and directly traceable to the zygote from which the asexual generations started. But if genetic variability is not found in asexual reproduction, the question still remains, Can the other kind of variations— namely, those due to the direct action of external forces upon the organism—be transmitted in asexual reproduction? Now we have already seen that the effect of external agencies acting upon the organism must be regarded under two heads, accord- ing as to whether the reproductive organs are or are not affected. If the reproductive organs are not affected, then variations caused by the impact of external forces will not be transmitted ; if, on the other hand, they are affected, the next generation will show the effect. We have further seen that in the case of sexual reproduction a modification of the repro- ductive organs will, because of the intervention of conjugation, appear as an increase in genetic variability only. How will the matter stand in the case of asexual reproduction? First, with regard to modifications which do not affect the reproductive system—they, as in sexual reproduction, will not be transmitted. Secondly, as regards modifications which do affect the repro- ductive organs—they will be transmitted, z.¢. they will affect the next generation; and the question arises, How will they be transmitted ? For here we have the opportunity wanting in the case of sexual reproduction of studying the transmission of modifications of the reproductive system without the compli- cations introduced by the act of conjugation. In considering this matter, it must be remembered that the reproductive organs are, with regard to external influences, exactly as any other organ. They can be modified either directly or indirectly, though they are in animals often less liable to direct modification by reason of their internal position.* These modifications may, as in the case of other organs, be obvious to the eye of the observer, or they may be so slight as only to be detected by an alteration of function. Now, in the case of the reproductive organs this alteration of function will show itself in the individuals of the next generation (if not be- fore) which proceed directly and without any complication from the affected tissue. How will these individuals be affected ? Will they all be affected in the same kind of way or will they they be affected in different ways? -Finally, will the modi- 1 Weismann, ‘‘ On Heredity,” vol. ii. English edition, p. 161. Warren E., ‘‘Observation on Heredity in Parthenogenesis,” Proc. Roy. Sac., 65, 1899, p- 154. These are the only observations I know of cn this subject. They tend to show the presence of a slight variability, but they are not entirely satisfactory. In connection with this matter, I may refer to Weis- mann’s view that Cyfa7s veptans, the species upon which his observations were made, reproduces entirely by parthenogenesis, and has lost the power of sexual reproduction, ‘This view is based on the fact that he has bred forty consecutive parthenogenetic generations and has never seen a male. As Weismann bases some important conclusions on this view, with regard to the importance of conjugation in rejuvenescence of organisms, I may point out that the fact that he has bred forty successive generations and has never seen a male cannot be regarded as conclusive evidence that males never appear. We know of many cases in which reproduction can continue for more than forty generations without the intervention of conjugation, e.g. ciliated infusoria, many plants, and of other species of crustacea in which the male is very rare and only appears after long intervals. 2 How far the abnormal position of the testes of mammalia may receive its explanation in this connection is a question worthy of consideration. 508 NATURE [SEPTEMBER 21, 1899 fication last their lives only, or will it continue into subsequent asexually produced generations ? Let us endeavour to answer these questions :— (1) How will the offspring be affected? That will depend entirely upon how the reproductive organ was affected. Will the modification in the offspring have an adaptive relation whatever to the external cause? Now here we have a capital opportunity, an opportunity not afforded at all by sexual reproduction, of examining by experiment and observation the Lamarckian position. My own opinion is that there will be no relation of an adaptive kind between the external cause and the modification of the offspring. For instance, let us imagine, as an experiment, that a number of parthenogene- tically reproducing organisms are submitted to a temperature lower than that at which they are accustomed to live. Let us suppose that the cold affects their reproductive organs and pro- duces a modification of the offspring. Will the modification be in the direction of enabling the offspring to flourish in a lower temperature than the parent? My own opinion, as I have said, is that there will probably be no such tendency in the offspring, if all possibility of selection be excluded. But that is only an opinion. The question is unsettled, and must remain unsettled until it is tested upon asexually reproducing organisms. (2) Will they all be affected in the same kind of way? Yes, presumably they will. I arrive at this conclusion, not by ex- periment, but by reasoning from analogy. In the case of other organs of the body, the same external cause produces in all in- dividuals acted upon, roughly speaking, the same kind of effect, e.g. action of sun upon skin, effect of transplanting maize, Porto Santo rabbits, &c. The question, however, cannot be settled in this way. It requires an experimental answer (3) Will the modification last beyond the life of the indi- viduals produced by the affected reproductive organ? I can give no answer to this question. We have no data upon which to forma judgment. We cannot say whether it is possible per- manently to modify the constitution of an organism in this way, or whether, however strong the cause may be, consistently of course with the non-destruction of life, the effects will gradually die away—it may be in one, it may be in two or more genera- tions. There are cases known which might assist in settling these questions, but I must leave to another opportunity the task of examining them. I refer to such cases as Arfemita salina, various cases of bud variation which cannot be included under the head of growth variation. Senile Decay and Rejuvenescence of Organisms. Another question, also of the utmost importance, confronts us at this point. As is well known, organisms are liable to wear and tear, sooner or later some part or parts essential to the maintenance of the vital functions wear out and are not renewed by the reparative processes which are supposed to be continually taking place in the organism. This constitutes what we call senile decay, and leads to the death of the organism. As a good example of the kind of cause of senile decay, we may men- tion the wearing out of the teeth, which in mammals at any rate are not replaced ; the wearing out of the elastic tissue of the arterial wall, which is probably not replaced. There is no reason to suppose that the reparative process of any organism is sufficiently complete to prevent senile decay. There is probably always some part or parts which cannot be renewed, even in the simplest organisms. Maupas has shown that this holds for the ciliated Infusoria, and he has also shown how the renewal of life, which of course must be effected if the species is to con- tinue, is brought about. He has shown that it is brought about by conjugation, during which process the organism may be said to be put into the melting-pot and reconstituted. For instance, many of the parts of the conjugating individuals are renewed, including the whole nuclear apparatus, which there is every reason to believe is of the greatest importance to living matter. On reconsidering the life of the Metazoa in light of the facts established by Maupas for the Infusoria, we see that all Metazoa are in a continual state of fission, as are the ciliated Infusoria. They are continually dividing into two unequal parts, one of which we call the parent and the other the gamete. The parent Metazoon must eventually die; it cannot be put into the melting-pot ; its parts cannot be completely renovated. The gamete can be put into the melting-pot of conjugation, and give rise to an entirely reconstituted organism, with all the parts and organs brand new and able to last for a certain time, which is the length of life of the individual of the species. NO. 1560, VOL. 60] Is there any other way than that of conjugation by which an organism can acquire a complete renewal of its organs? Is the renewal furnished by the development of all the parts afresh which takes place ina parthenogenetic ovum such a complete renewal? This question cannot now be certainly answered, but the balance of evidence is in favour of a negative answer. And this view of the matter is borne out by a consideration of the facts of the case. In all cases of conjugation which have been thoroughly investigated, the nuclear apparatus is completely re- newed. It would appear, indeed, as though the real explanation of the uninuclear character of the Metazoon gamete is to be sought in the necessity of getting the nuclear apparatus into the simplest possible form for renewal. Now in the development of a parthenogenetic ovum the ordinary process of renewal of the nucleus is often in partial abeyance. As a rule, it only divides once instead of twice, and there is, of course, no reinforcement by nuclear fusion. It is, of course, possible that the reinforce- ment by nuclear fusion which occurs in conjugation may have a different explanation from the nuclear reconstitution which takes place in the formation of polar bodies and similar struc- tures. On the other hand, it may all be part of the same pro- cess. We cannot tell. So that we are unable to answer the question whether for complete rejuvenescence a new formation of all parts of the organism is sufficient, or whether a reconstitu- tion of the nuclear apparatus of the kind which takes place in the maturation of the Metazoon ovum and the division of the micro-nucleus of Paramcecium is also required; or, finally, whether in addition to the latter phenomenon a reinforcement and reconstitution by fusing with another nucleus is also neces- sary for that complete rejuvenescence which enables an organism to begin the life cycle again and to pass through it completely. With regard to buds in plants, there is reason to believe that they share in the growing old of the parent. That is to say, if we suppose the average life of the individual to be 100 years, a bud removed at 50 will be 50 years of age, and only be able to live on the graft for 50 more years. Heredity. Having now spoken at some length o. the phenomenon of variation, I must proceed to consider from the same general point of view the phenomenon of heredity. As we have seen, in asexual reproduction heredity appears, as a general rule, if not always, to be complete. The offspring do not merely present resemblances to the parent—they are identical with it. And this fact does not appear to be astonish- ing when we consider the real nature of the process. Asexual reproduction consists in the separation off of a portion of the parent, which, like the parent, is endowed with the power of growth. In virtue of this property it will assume, if it does not already possess it, and if the conditions are approximately similar, the exact form of the parent. It is a portion of the parent ; it is endowed with the same property of growth ; the wonder would be if it assumed any other form than that of the parent. Indeed, it is doubtful if the word heredity would ever have been invented if the only form of increase of organisms was the asexual one, because there being no variation to con- trast with it, it would not have struck us as a quality needing a name, any more than we have a name for that property of the number two which causes it to make four when duplicated. The need for the word heredity only becomes apparent when we consider that other form of reproduction in which the real act of reproduction is associated with the act of conjugation. Looking at reproduction from a broad point of view, we may sum up the difference between the two kinds, the sexual and the asexual, by saying that, whereas the essence of sexual repro- duction is the formation of a new individuality, asexual re- production merely consists in increasing the number of one kind of individual. From this point of view sexual reproduction is better termed the creation of a new individuality, for that, and not the increase in the number of individuals, is its real result. Inasmuch as conjugation of two organisms is the essential feature of sexual reproduction, it would appear that the number of individuals would be actually diminished asa result of it ; and this does really happen, though ina masked manner, for we are not in the habit of looking upon the spermatozoon and ovum as individuals, though it is absurd not to do so, as they contain latent all the properties of the species, and are sometimes able to manifest these properties (parthenogenetic ova) without con- jugating. In some of the lower organisms the fact that con- iugation does not result in an increase of the number of SEPTEMBER 21, 1899] NATURE 509 individuals, but only in the production of a new individuality, is quite apparent, for in them two of the ordinary individuals of the species fuse to form one (many Protozoa). So that sexual reproduction gives us a new individuality which can spread to almost any extent by asexual reproduction. This asexual reproduction gives us a group of organisms which is quite different from a group cf organisms produced by sexual re- production. Whereas the latter groups constitute what we call species, the former group has, so far as I know, no special name, unless it be variety ; but variety is not a satisfactory name, for it has been used in another sense by systematisers. Heredity, then, is really applicable only to the appearance in a zygote of some of the properties of the gametes. A zygote has this property of one of the precedent gametes, and that property of the other, in virtue of the operation of what we call heredity ; it has a third property possessed by neither of the precedent gametes in virtue of the action of variation, the nature of which we have already examined. It is impossible to say which property of a gamete will be inherited, and it is impossible to predict what odd property will result from the combination of the properties of the two gametes. Of one thing only are we certain, that they are never the same in zygotes formed by gametes produced in immediate succession from the same parent. We may thus regard the activities of the zygote as the re- sultant of the dashing together of the activities of the gametes. Conjugation, then, is a process of the utmost -importance in biology ; it provides the mechanism by which organisms are able to vary, independently of the conditions in which they live. It lies, therefore, at the very root of the evolution problem; the power of combining to form a zygote is one of the funda- mental properties of living matter. Species. Now let us consider one of the effects of this property upon organisms. The effect to which I refer is the division of animals into groups called species. Species are groups of organisms the gametes of which are able to conjugate and pro- duce normal zygotes. Now in nature there appear to be many causes which prevent gametes from conjugating. First and most important of all is some physical incompatibility of the living matter which prevents that harmonious blending of the two gametes which is essential for the formation of a normal zygote. Very little is known as to the real nature of this in- compatibility ; in fact, it is hardly an exaggeration to say that nothing is known. It may be that there is actual repulsion between the gametes, or it may be, in some cases, at least, that the gametes are able to fuse, but not to undergo that intimate blending which is necesary for the production of a perfect zygote. In some cases we know that something like this happens ; for instance, a blend can be obtained between the horse and the ass, but it is not a perfect blend, the product or zygote being imperfect in one most important particular— namely, reproductive power. A second cause which prevents conjugation is a purely me- chanical one—viz. some obstacle which prevents the two gametes from coming together. As an instance of this I may refer to those cases amongst plants in which conjugation is im- possible, because the pollen tube is not long enough to reach the ovule. In yet other cases conjugation is impossible because the organisms are isolated from one another either geographic- ally or in consequence of their habits. There are probably many causes which prevent conjugation, but, whatever they may be, the effect of them is to break up organisms into specific groups, the gametes of which do normally conjugate with one another. In many cases, no doubt, the gametes of organisms which are kept apart in nature by mechanical barriers will conjugate fully if brought together. But in the great majority of cases it is probable no amount of proximity will bring about complete con- jugation. There is physical incompatibility. Here is a fruitful opening for investigation. Observations are urgently needed as to the real nature of this incompatibility. Importance of the Study of Variation, Another and most important effect o: conjugation is, as we have seen, the much-spoken-of constitutional or genetic varia- tions. They are, as we have already insisted, of the utmost importance to the evolutionist. Evolution would have been NO. 1560, VOL. 60] impossible without them, for it is made up of their summation. It becomes, therefore, desirable to find out to what extent a species is capable of varying. This can only be done, as Mr. Bateson has pointed out, by recording all variations found. Mr. Bateson, in his work already referred to, has carried this out, and has shown the way to a collection of these most important data. In order to carry it further, I would suggest that the collection be made, not only for structure, but also for function. This has been done largely for the nervous functions by psychologists and naturalists who pay special attention to the instincts of animals ; but we want a similar collection for other functions. For in- stance, the variations in the phenomena of heat and menstruation, and of rut amongst mammals, and so on. To do this is really only to apply the methods of comparative anatomy and com- parative physiology to the members of a species, as they have already been applied to the different species and larger groups of the animal kingdom. Such investigations cannot fail to be of the greatest interest. Indeed, when we have learnt the normal habits and_ structure of a species, what more interesting study can there be than the study of the possibilities of variation contained within it ? Then, when we know the limits of variability of any given specific group, we proceed to try if we can by selective breeding or alteration of the conditions of life alter the variability, and per- haps call into existence a kind of variation quite different in character from that previously obtained as characteristic of the species. The Evolution o Heredity and the Origin of Variation. These remarks bring me to the consideration of a point to which I am anxious to call your attention, and which is an important aspect of our subject. Has the variability of organisms ever been different from what it is now? Has or has not evolution had its influence upon the property of organisms as it is supposed to have had upon their other properties? There is only one possible answer to this question. Undoubtedly the variability of organisms must have altered with the progress of evolution. It would be absurd to suppose that organisms have remained constant in this respect while they have undergone alteration in all their other properties. If the variability of organisms has altered, it becomes necessary to inquire in what direction has it altered? Has the alteration been one of dimin- ution, or has it been one of increase? Of course, it is possible that there has been no general alteration in extent with the course of evolution, and that the alteration, on the whole, has been one of quality only. But passing over this third possi- bility, let us consider for the moment which of the two first- named alternatives is likely to have occurred. According to the Darwinian theory of evolution, one of the most important factors in determining the modification of or- ganisms has been natural selection. Selection acts by pre- serving certain favourable variations, and allowing others less favourable to be killed off in the struggle for existence. It thus will come about that certain variations will be gradually eliminated. Meanwhile the variations of the selected organisms will themselves be submitted to selection, and certain of these will be in their turn eliminated. In this way a group of organisms becomes more and more closely adapted to its sur- roundings ; and unless new variations make their appearance as the old unfavourable ones are eliminated, the variability of the species will diminish as the result of selection. Is it likely that new variations will appear in the manner suggested ? To answer this question we must turn to the results obtained by human agency in the selective breeding of animals. The experience of breeders is that continued selection tends to produce a greater, and greater purity of stock, characterised by small variability, so that if the selective breeding is carried too far, variation almost entirely ceases, and there is little opportunity left for the exercise of the breeder’s art. When this condition has been arrived at, he is obliged, if he wants to produce any further modifications of his animals, to introduce new blood—z.e. to bring in an individual which has either been bred to a different standard, or one in which the variability has not been so com- pletely extinguished. ; . It would thus appear, and I think we are justified in hold- ing this view, at any rate provisionally, that the result of con- tinued selection will be to diminish the variability, of a species ; and if carried far enough, to produce a race with ‘so little variability, and so closely adapted to its surroundings, that the 510 slightest alteration in the conditions of life will cause extinction. ’ If selection tends to diminish the variability of a species, then it clearly follows that as selection has been by hypothesis the most important means of modifying organisms, variation must have been much greater in past times than it is now. In fact, it must have been progressively greater the farther we go back from the present time. The argument which I have just laid before you points, if carried to its logical conclusion—and I see no reason why it should not be so carried—to the view that at the first origin of life upon the earth the variability of living matter consequent upon the act of conjugation must have been of enormous range : in other words, it points to the view that heredity was a much less im- portant phenomenon than it is at present. Following out the same train of thought, we are inevitably driven to the conclusion that one of the most important results of the evolutionary change has been the gradual increase and perfection of heredity as a function of organisms anda gradual elimination of vari- ability. This view, if it can be established, is of the utmost import- ance to our theoretical conception of evolution. because it enables us to bring our requirements as to time within the limits granted by the physicists. If variation was markedly greater in the early periods of the existence of living matter, it is clear that it would have been possible for evolutionary change to have been effected much more rapidly than at present—especially when we remember that the world was then comparatively un- occupied by organisms, and that with the change of conditions consequent on the cooling and differentiation of the earth’s sur- face, new places suitable for organic life were continually being formed. It will be observed that the conclusion we have now reached, viz. that variation was much greater near the dawn of life than it is now, and heredity a correspondingly less im- portant phenomenon, is a deduction from the selection theory. It becomes, therefore, of some interest to inquire whether a suggestion obtained by a perfectly legitimate mode of reasoning receives any independent confirmation from other sources. The first source of facts to which we turn for such confirmation must obviously be paleontology. But paleontology unfortunately affords us no help. The facts of this science are too meagre to be of any use. Indeed, they are wanting altogether for the period which most immediately concerns us—namely, the period when the existing forms of life were established. This took place in the prefossiliferous period, for in the earliest fossil- iferous rocks examples of almost all existing groups of animals are met with. But although paleontology affords us no assistance, there is one class of facts which, when closely scrutinised, do lend some countenance to the view that when evolutionary change was at its greatest activity, ze. when the existing forms of life were being established, variation was considerably greater than it is at the present day. But as this address has already exceeded all reasonable limits, and as the question which we are now ‘approaching is one of very great complexity and difficulty, I am reluctantly compelled to defer the full consideration and treatment of it to another occasion. Ican only hope that the far-reaching importance of my subject and the interest of it may to some extent atone for the great length which this address has attained. APPENDIX. The following observations on the condition of the male re- productive organs in highly variable plants are quoted from Darwin’s ‘Variation of Animals and Plants under Domes- tication,” vol. ii. p. 256 e¢ seg. In certain plant hybrids which are highly variable, it is known that the anthers contain many irregular pollen-grains. Exactly the same fact has been noticed by Max Wichura in many of our highly cultivated plants which are extremely variable, and which there is no reason to believe have been hybridised, such as the hyacinth, tulip, snapdragon, potato, cauliflower, &c. 1 The expression extinction of species seems to be used in two senses which are generally confused. Firstly, a species may become modified so that the form with which we are familiar gradually gives place to one or more forms which have been gradually produced by its modification. That is to say, a character orseries of characters becomes gradually modified or lost in successive generations. This is not really extinction, but develop- ment. Secondly, a speeies may gradually lose its variability, and become fixed in character. If the conditions then change, it is unable to adapt itself to them, and becomes truly extinct. In this case it leaves no descendants. We have to do with death, and not with development. NO. 1560, VOL. 60] NATURE [SEPTEMBER 21, 1899 The same observer also ‘‘finds in certain wild forms the same coincidence between the state of the pollen and a high degree of variability, as in many species of Rebus ; but in 2. caestus and ¢daeus, which are not highly variable species, the pollen is sound.” A little further on Darwin says ‘‘ these facts indicate that there is some relation between the state of the reproductive organs and a tendency to variability ; but we must not conclude that the relation is strict.’” Finally he sums up the matter in these words: ‘‘ On the whole it is probable that any cause affecting the organs of reproduction would likewise affect their product—that is, the offspring thus generated.” NOTES. In his address to the French Association, Boulogne meeting, Dr. P. Brouardel took as his theme ‘“ Hygiene and its Progress during the last 100 Years.” He paid special homage to the memory of the great Englishman and Frenchman, Jenner and Pasteur, who had done so much for the promotion of medical science. The first operation in vaccination made in France was performed at Boulogne, June 18, 1800. A public monument—a statue of Jenner—records the event. Referring to some preventive diseases, Dr. Brouardel remarked that in the French army the mortality from typhoid fever is now about 12 in 10,000, and in the present state of the water supply of many towns it is believed that this mortality will not be much reduced. In the German army, however, the mortality from typhoid fever is as lowas 1 and 2 per 10,000, owing doubtless to the fact that an order of a Government authority addressed to any municipal body is immediately carried out, so that an impure water supply has soon to be replaced by a better one. But though some French municipalities are indifferent to their responsibilities, others do their duty well, and the mortality from typhoid fever for the whole of France is only 3 per 10,000. Dr. Brouardel referred to several other subjects which came within the range of pre- ventive medicine. at the recent THE application of the Jenner Institute of Preventive Medi- cine for permission to alter the memorandum of association so as to enable the institute to avail itself of Lord Iveagh’s gift of 250,000/7, was granted by Mr. Justice Cozens Hardy on September 13. AFTER four months’ work on his yacht, Dr. H. C. Sorby, F.R.S., has returned to Sheffield with many hundred specimens of marine animals, preserved by his new methods, so as to show lifelike character and natural colour. THE Director of the Marine Observatory of San Fernando announces that the Spanish Minister of Finance has given in- structions that all instruments intended for observations of the eclipse of the sun on May 27, 1900, are to be admitted free of duty. Sirk WILLIAM PREECE, K.C.B., has recently been making experiments with an electromagnetic system of wireless tele- graphy in the Menai Straits. Using a telephone asa receiver, he has succeeded in establishing communication between stations half a mile apart, the messages heard being signals on the Morse code. WE learn from the Scéentzfic American that Prof. J. B. Hatcher, of Princeton University, has just returned from his geological expedition to Patagonia. The primary object of Prof. Hatcher's expedition was to make the most extensive collections possible of fossils of Patagonia. He also devoted considerable attention to gathering ethnological, botanical and zoological specimens. The first Mesozoic mammals ever dis- covered were found in Patagonia on this expedition, and upward of thirty cases of Mesozoic vertebrates were shipped SEPTEMBER 21, 1899 | north. Naturally Prof. Hatcher gathered much valuable material illustrating the life and customs of the Patagonian Indian tribes, and he has obtained an important series of photographic negatives which depict the geological and physiographic features of that region. THE British Central Africa Gazette (July 24), published at Zomba, announces the arrival at Nyasa of Mr. J. E. S. Moore, who visited Lakes Shirwa, Nyasa, and Tanganyika in 1896 under the auspices of the Royal Society, and has again returned to Central Africa to survey the basin of Lake Tanganyika, to collect specimens of the aquatic fauna and flora, and to study the geological history of this portion of the great Central African rift. Mr. Moore has with him a complete set of apparatus for deep-water dredging, and the results of the present expedition should be even more satisfactory and interesting than those of the previous investigation. On the way to Tanganyika, deep sounding and dredging operations will be made in Lake Nyasa, the Administration gunboat Gzendolen having been placed at the disposal of the expedition for this purpose. It is intended to spend several months on Lake Tanganyika, and, after leaving the north end of that lake, to proceed to Lakes | Kivu, Albert Edward, and Albert, whence it is proposed to make for the East African coast. WE regret to see the announcement of the death of M, Gaston Tissandier, the founder of our Parisian namesake, Za Nature, and the author of a number of scientific works. For many years M. Tissandier devoted much atténtion to ballooning, and made many balloon ascents, during which he obtained in- formation of value to aéronautics and meteorology. The results of his investigations will be found in the Comptes rendus of the Paris Academy of Sciences. He was nominated president of the French Association of aérial navigation, and in £876 received from the Association the Janssen gold medal. His first memoir on the application of electricity to aérial navigation was crowned by the Paris Academy of Sciences. In 1886, M. Tissandier was made a member of the committee on aéronautics by the Minister of War, and also of the civil committee on the same subject by the Minister of the Interior. He was a member of many scientific societies in France, and a vice-president of the French Meteorological Society. He was made a Chevalier of the Legion of Honour in 1872, and in 1893 the Society for the Encouragement of National Industry awarded him the grand gold medal. In addition to his scientific papers, M. Tissandier was the author of several volumes on physics, chemistry, photography, and ballooning. Mr. C. E. STROMEYER has sent us a stereoscopic photograph of what appears to him to have been an induced lightning flash, taken by Mr. S. Jewsbury at Didsbury. The camera by which the photograph was obtained was placed upon the sill of an open window during a thunderstorm, in order to depict any flashes of lightning which might come within its field of view. No flashes were seen in this part of the sky, but when the plate was developed a broken streak of light appeared upon the two pictures. The trail is horizontal and directed towards a lamp- post in a neighbouring road. As similar markings are often found on plates when lighted lamps are in the field, their electrical origin in the present case is difficult to establish ; for they may have been produced while the camera was being placed in position, or taken away, with the lens off. Nevertheless the photograph furnishes interesting material for speculation. Mr. T. KINGSMILL sends us two cuttings from the Shanghai Mercury referring to two electric displays of an unusual character observed at Shanghai on July 19 and August 10. On the former occasion it is stated :—‘‘ The northern sky was NO. 1560, VOL. 60] NATURE 511 in an almost constant blaze of light. Flashes came sometimes from two centres, as though there were an elliptical area of disturbance from whose foci were sent forth the shafts of lightning. At times these flashes would take the opposite course, and starting from the circumference make their way to the foci. Though the lightning flashes reached within twenty- five degrees of the zenith, and were vigorous enough in all conscience, yet nothing but the faintest distant rumbling could be heard.” On August 10 ‘‘ the reflection of lightning was seen from the S.W. and gradually increased in brightness until at about 7.50 it had reached the zenith.” The report states that ‘‘the lightning played over nearly the whole of the exposed sky, sometimes six and seven streamers at a time lighting up the sky. They were different in appearance from ordinary forked lightning, having rather the appearance of a network of ribbons crossing the exposed sky in all directions, like the dis- charges in a vacuum tube. The most unusual circumstance was that these discharges, though most vivid, were almost noiseless, and could scarcely be heard above the ordinary jinrickshaw traffic of the street, the only accompanying sound| to the brightest display even in the zenith being a low rumbling, as of ordinary very distant thunder.” Mr. Kingsmill remarks- that both displays were synchronous with distant typhoons. Av a meeting of the Lincolnshire Naturalists’ Union and the Lincolnshire Science Society, on September 11, Dr. G. M. Lowe, the president of both Societies, expressed the hope that something would soon be done to give science—both natural and’ physical—in Lincolnshire, first, a permanent home, secondly, the means of making useful observations, and thirdly, of recording them. The first requires the establishment of a museum, which: would at once be a memorial of the great men who had been: born and lived in Lincolnshire, amongst whom may be mentioned! Isaac Newton, Sir John Franklin, and Mr. John Cordeaux, As: a repository of specimens of the fast disappearing fauna and flora of our former fen country, of specimens of local antiquarian interest, of specimens bearing on the technique of our local arts and manufactures, a museum worthy of Lincolnshire would soon become invaluable. Next month the county authorities will consider an application for space within the Old Keep of the Castle, to erect buildings for an observatory for the reception of astronomical instruments offered to the county, and for a meteor-~ ological station. A third requirement is a means of recording and preserving the observations and papers of members of the scientific societies in the county. A magazine devoted to. natural and physical science could, Dr. Lowe felt sure, be supported by Lincolnshire alone; and if the writers of ob- servations and of papers on scientific subjects could be per- suaded to drop the pedantic, and use as far as possible a simple phraseology, a highly interesting and useful publi- cation could be provided, which would have a stimulating effect in directing the scientific education of the younger generation. WE have received from Prof. A. Klossovsky a copy of a paper read before the congress of naturalists, &c., at Kieff, entitled, ‘*The Physical Life of our Planet.” The author treats the. subject on the supposition that the earth is similar to a living organism, in which the various functions and elements are closely connected according to certain laws. He considers that even the variations of terrestrial magnetism depend upon a system of currents which traverse the atmosphere and are in evident corre- lation with the cyclonic activity of the air, and, further, that the magnetic and electric fields have an influence on the pro- gress of phenomena at the surface of the earth. He gives some interesting accounts of the most recent acquisitions of science in the determination of the different forces which constitute the physics of the globe. 512 Tue U.S. Hydrographic Office has received a_ sufficient number of reports to enable it to lay down, with substantial accuracy, the track of the destructive West India hurricane referred to in our issue of August 17 (p. 374). It appears to have been first encountered on August 3, in lat. 11° 51’ N., long. 35° 42’ W., further east than any tropical storm hitherto reported to that Office. At noon (Greenwich time) on the 7th, observations of barometers and winds between St. Kitts and Barbados showed unmistakably the presence of a hurricune to the eastward. The centre of the storm reached Porto Rico on the 8th, Haiti on the 9th, Bahamas on the 12th, and Jupiter, on the Florida coast, on the 13th, and then continued its path parallel to the general trend of the U.S. coast, where vessels continued to report gales of hurricane force until the 19th. The lowest barometer reading, 28°35 inches, appears to have occurred off the Florida coast on August 14. When the hurricane was last reported, in the afternoon of the 21st, it was near lat. 40° N. and long. 60° W., much weakened in energy. The life of the storm is longer than any hitherto reperted to the Hydrographic Office. Tue thirty-sixth annual report of the Government Cinchona Plantation in Sikkim, by Surgeon-Major D. Prain, shows that the issues of quinine during the year 1897-98 amounted to 10,939 Ibs., as against $482 lbs. in 1896-97. The medical depéts required 1710 Ibs. more than during the preceding year, and the sales to Government officers fcr distribution in their districts exceeded those of 1896-97 by 1986 lbs. As Sir George King feared, there has been a very marked decline in the demand for quinine for division into pice-packets for sale at Post-offices. The falling off in the demand, so far as Bengal is concerned, may be due to some special cause not active else- where ; at all events, 800 Ibs. have been asked for and supplied during the year for conversion into pice-packets in the North- western Provinces. DURING the year 1898-99 covered by the report of the Royal Botanic Garden, Calcutta, especial attention was given to the cultivation and distribution of plants of economic value. In connection with the question of rubber and gutta-percha, it has been ascertained, after examination of the milky juice of species of Sideroxylon belonging to the natural family Sapotaceze, that, though these species do not yield a true rubber, the material obtained from them might prove capable of being utilised for the various purposes for which gutta-percha or india-rubber is now employed. An interesting introduction to India during the year was Polygala butyracea, an African species, which yields an excellent vegetable oil. The cultivation and the identification of living plants yielding Indian products of hitherto doubtful origin were continued during the year with good results. We have received two papers on earthquakes registered at the observatory of Catania during the present year (So//. ae/l’ Accad. Gioenia di Sct. Nat. in Catania, 1899). Prof. Ricco describes the records of an earthquake in the Peloponnesus on January 22 made by the great seismometrograph, which is 25°3 m. long and has a mass of 300 kg., and by the Brassart seismometrograph. Mr. Arcidiacono gives an account of three diagrams obtained by the former instrument between 7 and 10 p-m. (G.M.T.) on May 3, the first being evidently made by a distant earthquake, which proved to be a strong shock in the Peloponnesus ; and the other two by local shocks originating below the south-west flank of Etna at the same spot as the destructive earthquake of May 14, 1898. The author suggests that the Sicilian focus was in a critical condition, and that the two movements there were precipitated by the earlier disturb-- ance in Greece. NO. 1560, VOL. 60] NATURE [SEPTEMBER 21, 1899 THE Free Museum of Science and Art of the University of Pennsylvania issues an illustrated Bu//etéz, in the last number of which (vol. ii. No, 2) an account is given of the new museum buildings in which will be lodged the fine collections of Drs. W. H. Furness and H. M. Hiller and Mr. A. C. Harrison, jun., from Borneo and adjacent islands; the collection from Sarawak is second only to that in the Sarawak Museum at Kuching, and in some respects probably surpasses it. The Bulletin contains a report on the recent excavations of the University at Nippur, an account of the Rittenhouse Orrery, and a catalogue of the recent additions to the Museum, some of the more interesting specimens being figured. THE Dorset County Council has set a good example in arranging for a series of reports with analyses of the soils of the county. The work has been carried out in Reading College under the superintendence of Mr. Douglas A. Gilchrist, and the soils have been analysed by Mr. C. M. Luxmoore and Mr. A. M. Ryley. The first annual report has just reached us; it forms Supplement No. viii. to the Jornal of Reading College, August 1899. Soils have been taken from areas where different geological formations are developed from the Lower Lias of the Vale of Marshwood to the Reading Beds near Wimborne ; a few analyses are also given of soils from Berkshire, Hampshire, and Oxfordshire. The results so far obtained are full of interest, and are likely to prove of great practical importance. Sugges- tions are made for the manuring of the principal farm crops on the different classes of soils, as well as on the suitability of the soils for particular crops. AN excellent ‘‘Sketch of the Geology of the Lower Carboniferous Rocks of Derbyshire” has been contributed by Mr. H. HH. Arnold Bemrose to the August number of the Proceedings of the Geologists’ Association. The Mountain Limestone with its caverns and lead mines, the Yoredale Rocks and the Millstone Grit are duly described, and the leading fossils are noted. Mention is made of Dr. Wheelton Hind’s opinion that the Yoredale Rocks of Derbyshire are newer than those of the typical district in Wensleydale. Further research on this subject is needed. References are made to the Glacial Drift, the Pleistocene Mammalia, the Warm Springs, and other subjects. A more particular account is given of the igneous rocks generally known as Toadstones, and of the occurrence of volcanic vents, as well as tuffs, lavas and sills. There are notes also on marmorised, dolomitised and silicified limestones. The article is well illustrated with maps, sections, and pictorial views. MANy persons are under the impression that shore-nesting birds make no nest, but lay their eggs indiscriminately among the shingle. This Mr. Patten, in the September number of the Trish Naturalist, shows to be a complete misconception so far as the Little Tern is concerned. As a matter of fact, the bird excavates a conical pit in the sand about two inches deep. Immediately round the ‘‘crater” a narrow zone of sand is cleared from shingle; and when completed and containing its full clutch of two or three eggs, the deepest part of the nest is filled with broken shells, into which the eggs are wedged with their points downwards. As the eggs are disproportionately large in relation to the bird, it is manifest that the position in which they are placed renders them most easily covered by the brooding hen. It has been assumed that the “crater” is excavated by the hen-bird ‘ breasting”’ the sand in the manner that sparrows dust themselves by the road-side, but the author is of opinion that the work is done with the beak. THE discussion in regard to the Ground-sloth whose skin and other remains have been found in a cave in Patagonia has assumed a new phase. It will be remembered that in a recent SEPTEMBER 21, 1899 | contribution to our columns Dr. Moreno stated his belief that the animal belonged to the genus Glossotherium (= Gryfo- therium), the creation of a new genus (Meomylodon) for its reception being accordingly superfluous. Accepting this de- termination, but using the synonym Gryfothertum, Dr. R. Hauthal, in a paper recently communicated to the “‘ Revista del Museo de la Plata” (vol. ix, p. 409), comes to the conclusion that the animal in question was kept by the prehistoric Indians of Patagonia in a domesticated state, and that the cave at Ultima Esperanza was the stable where the herd was nightly collected ! Several specimens of the hide, as well as abundant droppings in a dried state, have been obtained ; but in spite of this, the author is of opinion that all the remains date from prehistoric times. And he gives reasons for the belief that the creature cannot be living at the present day. Considering the animal in question to be distinct from the typical species, the author and his colleague Mr. Roth bestow the new title G. domesticum, apparently oblivious of Dr. Ameghino’s earlier name /s‘az, The promised continuation of this remarkable paper will be awaited with interest. SOME very interesting features in development are brought to light in Mr. J. S. Budgett’s ‘‘ Notes on Batrachians of the Para- guayan Chaco,” published in the last issue of the Quarterly Journal of Microscopical Sctence. It is well known that in some of the arboreal frogs the tadpole stage, to meet the necessities of existence, is more or less abbreviated ; and the author describes an instance of this in a species of Phy//omedusa, illustrating his notes with a beautiful coloured plate. After mentioning how the male and female hold together the edges of a leaf (which afterwards become united by the jelly of the egg-mass) during oviposition so as to form a funnel for the reception of the eggs, the developmental stages are described in detail. In the short period of six days the embryo leaves the egg as a pellucid tadpole of a bright green colour, whose only conspicuous parts are its eyes. The tadpole, which may have to travel several inches in order to reach the water, is hatched without a trace of yolk, and with the loss of external gills; breathing taking place by means of a median spiracle, and the lungs being distinctly visible through the body-wall. Pigment is locally developed next day ; and at the end of about five weeks the hind limbs appear. When both pairs of limbs are developed, the young frog lands, and sits quietly among the grass till its tail is com- pletely absorbed, when it is practically adult. THE second volume of Prof. G. O. Sars’ work on the Crustacea of Norway, dealing with the Isopoda, has just been completed. The volume is the first in which the Scandinavian Isopoda are treated as a whole, and it should be of much practical use to zoologists. The third volume of the work, now in preparation, will treat of the anomalous group Cumacea, and will consist of about 150 pages with sixty plates. Ar the Royal Victoria Hall, Waterloo Bridge Road, the following popular science lectures will be delivered on Tuesday evenings during October :—October 3, ‘‘ The Value of Nitrogen,” Prof. Holland Crompton, F.R.S. October 10, ‘‘ Liquid Air,” Prof. W. Ramsay, F.R.S. October 17, ‘*Source and Course of the River Thames,” Dr. C. G. Cullis. October 24, **Photographs taken in the Dark,” Dr. Russell, F.R.S. October 31, ‘* Kamchatka,” Captain Barrett Hamilton. THE additions to the Zoological Society’s Gardens during the past week include a Maholi Galago (Galago maholz) from South Africa, presented by Mr. James W. Park; two Black-eared Marmosets (Hafale penici/lata) from South-east Brazil, pre. sented by Mr. F. M. Still; a Guinea Baboon (Cynocephalus | sphinx, ?) from West Africa, presented by Mr. J. Huxley; a Black-backed Jackal (Canzs mesomelas), four Bristly Ground NO. 1560, VOL. 60] NATURE SIL) Squirrels (Xerzs sefosus), a Vulturine Eagle (Ayucla verreauxz, juv.), two Hispid Lizards (dvama hispida), four Delalande’s Lizards (Wucras delalandiz), seven Rufescent Snakes (Leptodzra hotambazia), four Crossed Snakes (Psammophis crucifer), five Rhomb-marked Snakes (Zrimerorhinus rhombeatus), eight Rough-keeled Snakes (Dasyfeltis scabra), an Infernal Snake (Boodon infernalis), two Puff Adders (ABztis arzetans) from South Africa, presented by Mr. J. E. Matcham ; a Fulmar (/z/arus glactalis) from Iceland, presented by Mr. G. S. Hett; a Lap- wing ( Vanellus cristatus), British, presented by the Rev. A. Barham Hutton; a Herring Gull (Lavus argentatus), British, presented by Mr. J. L. Bell; two Common Chameleons Chamaeleon vulgaris) from North Africa, presented by Mr. Ronald H. Archer; a Common Viper (Vifera berus), British, presented by Mr. P. Debell Tuckett ; a Kinkajou (Cercoleptes caudivolvulus) from South America, an Arctic Fox (Cazzs lagopus) from Finland, a Palm Squirrel (Sczurus palmarum, albino) from India, a Black-headed Conure (Conurus nanday) from Paraguay, deposited. OUR ASTRONOMICAL COLUMN. Homes’ CoMET 1899 @ (1892 III.).— Ephemerts for 12h. Greenwich Mean Time. Br. 1899. R.A Decl. el . ies. ss Chi) oT re (vA) Sept. 21 3 9 3598 +4445 197 01758 0'05727 22 9 31°29 44 57 203 23 Q 24°28 45 9 102 24 9 14°91 45 20 49°1 25 9 318 45 32 1674 0'1740 0'05809 26 8 49°09 45 43 31°8 27 8 32°62 45 54 34°8 28 8 13°75 46 5 25°0 29 7 52°50 46 16 2°0 O'1721. 0'05881 30 7 28°36 46 26 25°1 Ocha Tae2nS5 46 36 3471 2 6 34°46 46 46 28 2 3 3 6 3°71 +4656 7°2 071702 0705939 New Spectroscopic MULTIPLE STAR.—The San Francisco correspondent of the Standard (September 11) reports that Prof, W. W. Campbell, of the Lick Observatory, announces that he has obtained spectroscopic evidence that the North Pole star, Polaris, is in reality a system consisting of three bodies. Two of these revolve round each other in a period of fou days, and simul- taneously they together revolve around a third body, in the same manner as the earth and planets revolve round the sun. It is improbable that any of these distant bodies will ever be visible separately, their distance from each other being so small that it can only be detected by the change in wave-length of the lines in the spectrum of the system, owing to the continual approach and recession of each component during their mutual revolutions. SOUTHERN VARIABLE STARS.—In the Astronomical Journal (No. 468), Mr. R. T. A. Innes gives the results of observations on variable stars made at the Cape Observatory since 1896. The working catalogue was mainly derived from lists supplied by Prof. J. C. Kapteyn, who noted all suspected cases of variability in the course of his work on the Cape Photographic Durchmusterung. The present communication considers twenty- seven stars, of which one is probably of the Algol type. The period of this is found to be 12°906 days, and consequently this star is conspicuous as being the longest period Algol variable. Its position is R.A. 7h. 42m. 41°Is. | 875)' Decl. — 41° 40 ‘is 75), The visual variation of magnitude is from 9*5 to 10°7, and photographically from 9°3 to 10°2.. THE Bulletin de la Société Astr. de France for September contains several interesting papers.—‘‘* Photography of stellar spectra,” by Prof. A. Cornu, consists of a short description of the methods and results of researches into stellar constitution. MM. Flammarion and Antoniadi describe their most recent | observations of Mars, including illustrations showing the land- 514 markings and the variations of the polar cap with the seasons. M. Fm. Touchet contributes an illustrated account of his suc- cessful attempt to photograph the ‘‘ shadow cast by the planet Venus.”’ This he did on January 11, with an exposure of fifteen minutes, the object casting the shadow being an incandescent bulb-holder placed about 21 cm. from the plate.—Lastly, rather more than nine pages are devoted to a dissertation, by M. Rideau, on ‘‘the satellites of Jupiter,” dealing with their dimensions, surface, probable variability of brightness, eclipse and other phenomena. SOLID HYDROGEN. [X the autumn of 1898, after the production of liquid hydrogen was possible on a scale of one or two hundred c.c., its solidification was attempted under reduced pressure. At this time, to make the isolation of the hydrogen as effective as possible, the hydrogen was placed in a small vacuum test-tube, placed in a larger vessel of the same kind. Excess of the hydrogen partly filled the circular space between the two vacuum vessels. The apparatus is shown in Fig 1. In this way the evaporation was mainly thrown on the liquid hydrogen in the annular space between the tubes. In this arrangement the outside surface of the smaller tube was kept at the same temperature as the inside, so that the liquid hydrogen for the time was effectually guarded from influx of heat. With such a combination the liquid hydrogen was evaporated under some IO mm. pressure, yet no solidification took place. Seeing experiments of this kind required a large supply of the liquid, other problems were attacked, and any attempts in the direction Fiel, Fic 2. of producing the solid for the time abandoned. During the course of the present year many varieties of electric resistance thermo- meters have been under observation, and with some of these the reduction of temperature brought about by exhaustion was investigated. Thermometers constructed of platinum and platinum-rhodium (alloy) were only lowered 14° C. by exhaus- tion of the liquid hydrogen, and they all gave a boiling point of —245°C., whereas the reduction in temperature by evaporation in vacuo ought to be 5° C., and the true boiling point from —252° to —253° C. In the course of these experiments it was noted that almost invariably there was a slight leak of air, which became apparent by its being frozen into an air snow in the interior of the vessel, where it met the cold vapour of hydrogen coming off. When conducting wires covered with silk have to pass through india-rubber corks it is very difficult at these excessively low temperatures to prevent leaks, when corks get as hard as a stone, and cementscrack in all directions. The effect of this slight air leak on the liquid hydrogen when the pressure got reduced below 60 mm. was very remarkable, as it suddenly solidified into a white froth-like mass like frozen foam. My first impressions were that this body was a sponge of solid air containing the liquid hydrogen, just like ordinary air, which is a magma of solid nitrogen containing liquid oxygen. The 1 Read before the British Association (Section B), Dover Meeting, by Prof. James Dewar, F.R.S. NO. 1560, VOL. 60] NALORE [SEPTEMBER 21, 1899 fact, however, that this white solid froth evaporated completely at the low pressure without leaving any substantial amount of solid air led to the conclusion that the body after all must be solid hydrogen. This surmise was confirmed by observing that if the pressure, and therefore the temperature, of the hydrogen was allowed to rise, the solid melted when the pressure reached about 55 mm. The failure of the early experiment must then have been due to supercooling of the liquid, which is prevented in this case by contact with metallic wires and traces of solid air. To settle the matter definitely, the following experiment was arranged. A flask, Cc, of about a litre capacity, to which a long glass tube bent twice at right angles was sealed, as shown in Fig. 2, and to which a small mercury manometer can be sealed, was filled with pure dry hydrogen and sealed off. The lower portion, A B, of this tube was calibrated. It was surrounded with liquid hydrogen placed in a vacuum vessel arranged for exhaustion. As soon as the pressure got well reduced below that of the atmosphere, perfectly clear liquid hydrogen began to collect in the tube 4 B, and could be observed accumu- lating until, about 30 to 40 mm. pressure, the liquid hydrogen surrounding the outside of the tube suddenly passed into a solid while foam-like mass, almost filling the whole space. As it was not possible to see the condition of the hydrogen in the interior of the tube 4B when it was covered with a large quantity of this solid, the whole apparatus was turned upside down in order to see whether any liquid would run down AB into the flask c. Liquid did not flow down the tube, so the liquid hydrogen with which the tube was partly filled must have solidified. By placing a strong light on the side of the vacuum test-tube opposite the eye, and maintaining the exhaustion to about 25 mm., gradually the solid became less opaque, and the material in A B was seen to be a transparent ice in the lower part, but the surface looked frothy. This fact prevented the solid density from being determined, but the maximum fluid density has been approximately ascertained. This was found to be 0086, the liquid at its boiling point having the density 0°07. The solid hydrogen melts when the pressure of the saturated vapour reaches about 55mm. In order to determine the tem- perature, two constant volume hydrogen thermometers were used. One at o° C. contained hydrogen under a pressure of 269°8 mm., and the other under a pressure of 127 mm. The mean temperature of the solid was found to be 16° absolute under a pressure of 35 mm. All the attempts made to get an accurate electric resistance thermometer for such low tempera- ture observations have been so far unsatisfactory. Now that pure helium is definitely proved to be more volatile than hydrogen, this body, afier passing through a spiral glass tube immersed in liquid hydrogen to separate all other gases, must be compared with the hydrogen thermometer. For the present the boiling point which is 21° absolute at 760 mm., compared with the boiling point at 35 mm., or 16° absolute, enables the following approximate formula for the vapour tension of liquid hydrogen below one atmosphere pressure to be derived :— log £— 67341 — 83'28/T mm., where T = absolute temperature, and the pressure is in mm. This formula gives us for 55 mm. a temperature of 16°7° absolute. The melting point of hydrogen must therefore be about 16° or 17° absolute. It has to be noted that the pressure in the con- stant volume hydrogen thermometer, used to determine the tem- perature of solid hydrogen boiling under 35 mm., had been so far reduced that the measurements were made under from one- half to one-fourth the saturation pressure for the temperature. When the same thermometers were used to determine the boil- ing point of hydrogen at atmospheric pressure, the internal gas pressure was only reduced to one-thirteenth the saturation pres- sure for the temperatures. The absolute accuracy of the boiling points under diminished pressure must be examined in some future paper. The practical limit of temperature we can com- mand by the evaporation of solid hydrogen is from 14° to 15” absolute. In passing it may be noted that the critical temper- ature of hydrogen being 30° to 32° absolute, the melting point is about half the critical temperature. The melting point of nitrogen is also about half its critical temperature. The foam- like appearance of the solid when produced in an ordinary vacuum is due to the small density of the liquid, and the fact that rapid ebullition is substantially taking place in the whole mass of liquid. The last doubt as to the possibility of solid hydrogen having a metallic character has been removed, and for the future hydrogen must be classed among the non-metallic elements. Ee SEPTEMBER 21, 1899] AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. AS already notified, the forty-eighth meeting of the American Association for the Advancement of Science was held at Columbus, Ohio, on August 19-26 Dr. W. O. Thompson, President of the Ohio State University, welcomed the Associ- ation on behalf of the University, and Dr. Edward Orton, the President, in expressing the thanks of the Association, briefly referred to some of the scientific advances of the present century. The address of Prof. F. W. Putnam, the retiring President of the Association, was printed in NAruRE of September 7, and the following are extracts from some of the addresses delivered by the Presidents of the Sections. THE FUNDAMENTAL PRINCIPLES OF ALGEBRA, In his address to the Section of Mathematics and Astronomy, Prof. Alexander Macfarlane reviewed historically and critically the several advances which have been made in the present cen- tury respecting the fundamental principles of algebra. The conclusion reached, after a statement and criticism of algebraic symbols, operations and laws, is as follows :— If the elements of a sum or a product are independent of order, then the written order of the terms is indifferent, and the product of two such sums is the sum of the partial products ; but when the elements of a sum or of a product have a real order, then the written order of the elements must be preserved, though the manner of their association may be indifferent, and a power of a binomial is then different from a product. This applies whether the sum or product occurs simply, or as the index of a base. Descartes wedded algebra to geometry ; formalism tends to divorce them. The progress of mathematics within the century has been from formalism towards realism ; and in the coming century, it may be predicted, symbolism will more and more give place to notation, conventions to principles, and loose ex- tensions to rigorous generalisations. THE FIELD OF EXPERIMENTAL RESEARCH. Prof. Elihu Thomson described to the Section of Physics a few of the recent developments of physical science, and pointed out that physical research by experimental methods is both a broad- ening and a narrowing field. There are many gaps yet to be filled, data to be accumulated, measurements to be made with great precision, but the limits within which experimental work can be done are becoming, at the same time, more and more defined. In most fields of research progress in the future will depend in an increasing degree upon the possession, by the in- vestigator, of an appreciation of small details and magnitudes, together with a refined skill in manipulation or construction of apparatus. He must be ready to guide the trained mechanic, and be able himself to administer those finishing touches which often mark the difference between success and failure. In conclusion, Prof. Thomson remarked that his endeavours had been to indicate in his address directions in which the field of experiment may be extended, and to emphasise the fact that research must be carried on by extension of limits, necessitating more liberal endowment of research laboratories. The physicist must avail himself of the powers and energies set in play in the larger industrial enterprises, and finally the field of possible ex- ploration in physics by experimental methods has its natural boundaries, outside of which our advances in knowledge must be derived from a study of celestial bodies. The riddle of gravitation is yet to be solved. This all-per- meating force must be connected with other forces and other properties of matter. It will be a delicate task, indeed, for the total attraction between very large masses closely adjacent, aside from the earth’s attraction, is very small. Scientific facts are of little value in themselves. Their signi- ficance is their bearing upon other facts, enabling us to generalise and so to discover principles, just as the accurate measurement of the position of a star may be without value in itself, but in relation to other similar measurements of other stars may become the means of discovering their proper motions. We refine our instruments ; we render more trustworthy our means of observ- ation; we extend our range of experimental inquiry, and thus lay the foundation for the future work, with the full knowledge that, although our researches cannot extend beyond certain limits, the field itself is, even within those limits, inexhaustible. NO. 1560, VOL. 60] NATURE | THE DEFINITION OF THE ELEMENT. Prof. F. P. Venable briefly discussed the nature of the elements in his address to the Section of Chemistry. He passed in review some of the evidence which leads to the belief that the so-called elementary atoms are but compounds of an intimate peculiar nature, the dissociation of which has not yet been ac- complished. Referring to the conclusions to which investigations lead, it was remarked that the hypothesis that the elements are built up of two or more common constituents has a larger number of supporters, and would seem more plausible than Graham’s hypothesis. Some have supposed one such primal element by the condensation or polymerisation of which the others were formed. Others have adopted the supposition of two elements. There are many practical difficulties in the way of these sup- positions ; the lack of uniformity in the differences between the atomic weights, the sudden change of electro-chemical character, and the impossibility, so far, of discovering any law underlying the gradation in the properties of the elements with the increase of atomic weights, are some of the difficulties. In comparing these two hypotheses, that of Graham seems very improbable. It is possible to think of valency as dependent upon the character of the motion of the atom, but one cannot well conceive of a similar dependence of atomic weight and all the other properties. There remains, then, the hypothesis of primal elements by the combination of which our elements have been formed. These molecules are probably distinguished from the ordinary mole- cules by the actual contact and absolute union of the component atoms without the intervention of ether. Since these elemental molecules cannot as yet be divided, the name atom may be retained for them, but the idea of simplicity and homogeneity no longer belongs to them. The definition of an element as a body made up of similar atoms is equally lack- ing in fidelity to latest thought and belief, but chemists would scarcely consent to change it, and, indeed, it may well be re- tained, provided the modified meaning is given to the word atom. But, after all, an element is best defined by means of its properties. It is by close study of these that ‘its elemental nature is decided, and through them it is tested. Complete reliance can no longer be placed upon the balance and the supposed atomic weight. THE DEVONIAN SYSTEM OF CANADA, Mr. J. F. Whiteaves’s address to the Section of Geology and Geography was upon the present state of knowledge of the Devonian rocks of Canada, from a palontologist’s point of view. In accordance with long usage in Canada, the line of demarcation between the Silurian and Devonian systems was drawn at the base of the Oriskany sandstone. The information that has so far been gained about the Devonian rocks of Canada was considered in geographical order, from east to west, under the three following heads, viz. (1) The Maritime Provinces and Quebec; (2) Ontario and Keewatin; and (3) Manitoba and the North-west Territories. The present state of our knowledge of the Devonian rocks of the whole Dominion, from a purely palzeontological standpoint, was thus briefly summarised :—We now possess a fairly satis- factory knowledge of the fossils of the Devonian rocks of Ontario, and of the relations which these rocks bear to the typical section in the State of New York. The fossil plants of the Gaspé sandstones have been described and figured by Sir William Dawson, and the remarkable assemblages of fossil fishes from the Upper Devonian of Scaumenac Bay and Lower Devonian near Campbellton have been worked out somewhat exhaustively, the earlier collections in Canada, and the later ones by the best ichthyological authorities in London and Edin- burgh. We have now some idea of the fossil fauna of the Manitoba Devonian, and have added materially to our know- ledge of the fossils of the Devonian rocks of the Athabasca and Mackenzie River districts. But, on the other hand, our know- ledge of the organic remains of the Devonian of Nova Scotia is still in its infancy, and it would seem that the plant-bearing beds near St. John, N.B., which have so long been regarded as Devonian, may possibly be Carboniferous. In the Rocky Mountain region of Alberta we have not always succeeded in distinguishing Devonian rocks from Carboniferous, and we have yet to obtain a much fuller knowledge than we now possess of the Devonian fossils of Keewatin and the area to the south-west of James Bay. 516 NATURE [SEPTEMBER 21, 1899 ENGINEERING EDUCATION. The address of Prof. Storm Bull, before the Section of Mechanical Science and Engineering, was on engineering education as a preliminary training for scientific research work, The proposition put forward was that engineering education as furnished in the best technical schools of the world, together with the training obtained later in life as a practising engineer, provides the best preliminary preparation for the successful prosecution of scientific research work. UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Mr. A. G. ASHCROFT has been appointed Assistant Professor of Engineering at the Central College of the City and Guilds of London Institute. DuRING the winter session 1899-1900 at the University of Edinburgh, courses on practical experimental physiology, prac- tical chemical physiology, and practical histology, will be given every week day, in addition to the usual five months’ course on physiology. AmoncG the addresses to be delivered at the opening of the Medical Schools in the beginning of October are the following : —At the Middlesex Hospital the introductory address will be delivered by Mr. John Murray. At St. George’s Hospital the introductory address will be given by Dr. Howship Dickinson. At University College the session will be opened by Dr. G. F. Blacker. At St. Mary’s Hospital the address will be given by Mr. H. G. Plimmer. At Charing Cross Hospital the address will be delivered by Dr. Mitchell Bruce. At Guy’s the term begins on October 2, when the first meeting of the session of the Physical Society will be held at 8, in the new physiological theatre. Sir Samuel Wilks will preside. At the London School of Medicine for Women the introductory address will be given by the dean, Mrs. Garrett Anderson, after which the prizes for the past year will be distributed. The winter session of the London School of Tropical Medicine will open on October 2, when the new school will be formally opened to students. At St. Thomas’s Hospital the session will open on October 3, when the prizes will be distributed by Prof. Clifford Allbutt. The winter session at Mason College, Birmingham, will begin on October 2, when Sir William Gairdner will deliver the introductory address. At University College of South Wales and Monmouthshire, Cardiff, the address will be given on October 6 by Prof. A. W. Hughes. At Yorkshire College, Leeds, the address will be given on October 2, and the prizes distributed by Dr. Byrom Bramwell. The session at University College, Liverpool, will begin on October 3 with an address by the Rev. S. A. Thompson-Yates, who will afterwards distribute the prizes. The introductory lecture at Queen’s College, Man- chester, will be given on October 2 by Sir J. Crichton Browne. SCIENTIFIC SERIAL. American Journal of Science, September.—On the gas thermometer at high temperatures, by L. Holborn and A. L, Day. The authors seek fora type of gas pyrometer yielding the most trustworthy results, and eventually decide in favour of the iridio-platinum bulb as against porcelain. They fill the bulb with nitrogen, and use a saltpetre bath up to 750°, a zinc bath up to 900", and electric heating for still higher temperatures, since flame gases pass bodily through the metal.—On the flicker photometer, by O. N. Rood. The general idea of the photo- meter, which is independent of colour, is that the differently coloured beams of light traversing ils axis should illuminate the two surfaces of a rectangular prism, facing the eye, and that by the oscillations of a cylindrical concave lens its illuminated surfaces should alternately and in rapid succession be presented to the eye. The resulting flicker vanishes when the two surfaces have the same luminosity.—A quantitative investigation of the coherer, by A. Trowbridge. The greater the charging potential of the coherer, the more rapid is the rise of the conductivity per unit increase in quantity of electricity discharged. Probably every coherer has a critical value of the difference of potential below which it will not act. In the ball coherer used this was 8 volts. —Double ammonium phosphates of beryllium, zinc, and cadmium in analysis, by Martha Austin. The preparation of NO. 1560, VOL. 60] these double ammonium phosphates is described in detail, and their utility in analytical processes is indicated.—An Albertite- like asphalt in the Choctaw Nation, Indian Territory, by J. A. Taff. The mineral, in both its physical and chemical properties, is shown to be an asphalt, and only differs.from albertite in its solubility in turpentine. It occurs in veins from 4 to 25 feet thick.—A new meteorite from Murphy, Cherokee County, N.C., by H. L. Ward. The siderite described has a square fracture unusual in iron meteorites.—On the separation of alumina from molten magmas, and the formation of corundum, by J. H. Pratt. The separation of alumina is well illustrated in nature in the occurrence of corundum, spinel, and chromite in the rocks of the peridotite group. Experiments in the laboratory show that the separation of alumina as corundum from molten magmas is dependent upon the composition of the chemical compounds that are the basis of the magma, upon the oxides that are dissolved with the alumina, and upon the amount of the alumina itself. When the magma is composed of a magnesium silicate without excess of magnesia, all the alumina held by such a magma will separate out as corundum. SOCIETIES AND ACADEMIES. Paris. Academy of Sciences, September 11.—M. Maurice Lévy in the chair.—On a new form of the equations of dynamics, by M. P. Appell. Some remarks on the new form of equation indicated in the Comptes rendus of August 7 and 28. The results obtained can be expressed in one theorem, with which is connected the principle of least constraint of Gauss. —The Perseids of 1899, by M. G. Flammarion. The paper gives the results of the observations of MM. Antoniadi and Mathieu at the observatory of Juvisy on August 11, 12 and 13. The results are given in tabular form, and the directions of the meteors observed are shown upon a map.—Remarks by M. Bouquet de la Grye on the above paper. It would be possible to utilise shooting stars as a means of determining differences of longitude between places unprovided with the telegraph.—On some geometrical relations between two systems of points defined by algebraic equations, by M. S. Mangeot. CONTENTS. PAGE Eclipses’ . & lap ee © «0 -c) JO A French Writer on Classification. By F. A. D. . 489 Our Book Shelf :— Reinke : ‘‘ Die Welt als That."-—E. A.M... . . 490 Cauro: ‘La Liquéfaction des Gaz: Methodes nouvelles—Applications ” ae - . 490 Letters to the Editor :— Movement of Sea-Gulls with a Coming Change of Weather. — Lieut.-Colonel H. H. Godwin- Austen, F.R.S.. . .- cyt kel COM nitccaeed e4 ON Thermometric Scales for Meteorological Use.—H. Helm Clayton fg Py fo : kite : 491 The New Lunar Photographic Atlas . : 491 The Dover Meeting of the British Association. By W.H. Pendlebury .... . 2 i . 494 Section C.—Geology.—Opening Address by Sir Archibald Geikie, F.R.S., President of the Section “2 <) Gh gamers 5 Bie ee 496 Section D.—Zoology.—Opening Address by Adam Sedgwick, F.R.S., President of the Section 502 Notes he Ua re ok me 510 Our Astronomical Column :— Holmes’ Comet 1899 d (1892 III.) 513 New Spectroscopic Multiple Star . . .-. . . . «= 513 Southern Variable Stars . . ety —=nB lefines a Schnitt, and this is identical with the series for which #zC>2D. NO. 1561, VOL, 60] NATURE [SEPTEMBER 28, 1899 cannot, after due warning, distinguish @é, the area of a rectangle, from a@é, the product of two numbers, it is entirely his own fault. The figures are very good ; those on solid geometry have been very carefully drawn, and are nearly as effective as models would be. This isa great help to the beginner : he should bear in mind, however, that he must eventually be able to use a less pictorial figure, or even construct a diagram mentally im cases where an actual figure is too complicated to be useful. We should be rather inclined to suggest beginning with the more pictorial figures, and gradually reducing them to pure diagrams. Between a picture and a diagram there is the same sort of difference as there is between a photograph of an electrometer and a working drawing of the same instrument. GaBa MMe OUR BOOK SHELF. An Elementary Course of Mathematics. By H.S. Hall and F. H. Stevens. Pp. ix + 342. (London: Mac- millan and Co., Ltd., 1899.) IN preparing this book the object kept in mind was, as we are told in the preface, to provide in a simple and in- expensive volume a short course of arithmetic, algebra and Euclid specially adapted to the requirements of students who, after leaving school, desire to continue their study of elementary mathematics by partly attending evening classes and partly working privately at home. To attain the end in view, the compilers, in the first portion on arithmetic, have restricted themselves to simply providing the student with a series of progressive exercises arranged to extend over a winter session of thirty weeks ; a few additions, exercises with notes and hints, conclude this portion. Algebra is next dealt with, and no previous knowledge is here assumed, so that a progressive but elementary course with numerous examples is given, covering the usual ground up to quadratic equations. In the last section on Euclid only the first book is considered. In the case of each proposition a few notes and exercises will help the reader to master this book, while ad- ditional theorems and a large set of appropriate examples are added for further practice. For the purpose for which it is intended, this elementary course is well adapted. Carvell’s Nursery Handbook, with Hints. By J. M. Carvell. (London : THE contents of this “ Nursery Handbook” are arranged under a number of headings; for instance, “ The Nursery,” “Sleeping,” ‘“ Clothing,” “Feeding,” &c. But in each section the hints given seem to be selected at hap- hazard ; small details in some places are noted, while many points of importance are omitted. In fact, the book seems too disjointed to be of real value, and the information too scanty to serve as a practical guide. In many instances the directions are so short that without amplification they might easily be misinterpreted. Pp. 70. Barber, 1899.) Chats about the Microscope. By Wenry C. Shelley. Pp. 101. (London: The Scientific Press, Ltd., 1899.) YOUNG naturalists will find in this volume many useful hints on the collection and preparation of common objects for microscopical study, and will be guided to make observations of a number of minute organisms easily obtained. SEPTEMBER 28, 1899] NATURE 519 LETTERS TO THE EDITOR. The Editor does not hold himself responsible for opinions ex- pressed by his correspondents. Netther can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for thts or any other part of NATURE. No notice ts taken of anonymous communications. | The Life of a Star. THE letter of Prof. Perry on ‘‘ The Life of a Star,” published in your issue of July 13, is of interest to astronomers; and as the author of it evidently aims to be fair, I think it worth while to set right a misconception into which he has fallen. His reference to my paper in the Astronomical Journal (No. 455) shows that he has misconstrued the meaning of the symbol K in the formula a: =e . That paper was unfortunately very much abbreviated, and as I was not concerned with the analytical investigation of K, this constant was not sufficiently explained. Yet in my first note on this law in the 4. 7. (453), which he probably overlooked, it was anncunced that ‘‘ K isa constant different for each body.” Thus the constant K is not, as Prof. Perry supposes, the same for the whole universe, but varies from star to star, being a function of the mass, specific heat, emissive power, &c., into which we need not go at present. At the time of writing the paper in the 4. 7. (455) I had not seen the early paper by Ritter in Wredemann’s Annalen, 1878, S. 543, where he has reached by a different process a similar formula : Tyo za Tr, and anticipated a number of the conclusions to which I came independently. Ritter even applied this law to the temperature of the solar nebula when its periphery extended to the orbit of Neptune, and sagaciously observes that his conclusions do not agree with current views, but are yet uncontradicted by known facts. As I have prepared for the St. Louis Academy of Sciences a paper in which this whole matter is discussed with some detail, I will here merely summarise a few of the chief results. Suffice it to say that the formula T = = is shown to express a law of the utmost generality, for masses composed of one kind of gas ; and that even when the body is of heterogeneous constitution, made up of interpenetrating globes of different gases, the law suffers no essential modification except at very long intervals, when it would take the form T = — Bt) where 8 is a certain small secular coefficient, and ¢ the time. For a great epoch the term depending on 8 might be wholly neglected. The only hypothesis underlying the investigation is that of convective equilibrium, the validity of which is generally recognised by physical investigators. In order that the reader may see how far from metaphysical my argument really is, I add an elementary derivation of the law of temperature. Suppose a gaseous globe of radius Ry to be held in convective equilibrium by the attraction, pressure and temperature of its particles (the density and temperature decreasing from the centre co the surface), and let the temperature beneath the surface layer be T,. Let P, be the gravitational attraction exerted upon the thin layer of matter covering a unit surface of the globe, which may be regarded as the base of an elemental cone extending to the centre. Then suppose the globe to shrink by loss of heat toa radius R. If the original element of mass still covered a unit area, the pressure exerted upon its lower surface would thereby become P = Py ) But since the area of the initial \ix sphere surface has shrunk to S =8,(—) the area of the ele- a) mental conical base has diminished in the same ratio. As the force of gravity is increased, while the area upon which the element presses is decreased correspondingly, it follows that in the condensed condition of the globe, the gravitational pressure / 4 exerted upon a unit area is P = Py (R): The forces counter- 1p Prof. Nipher, in preparing the excellent papers which he has contri- buted to the St. Louis Acadeiny of Sciences, first drew attention to this reference. NO. 1561, VOL. 60] acting this increased pressure are obviously the resistance due to the increase in the mean density, and a possible change in temperature which might affect the elasticity of the gas. But the density of the original mass was a), and hence ¢ = on (=). By hypothesis the equilibrium of the globe is maintained by the elastic force of the gas under the heat developed by the gravit- ational shrinkage of the mass. If therefore the globe was in equilibrium when the gas just beneath the surface layer had a mean temperature Tp, to remain in equilibrium in the condensed condition, T, must be multiplied by a As T, Ry = constant, we may write the law of temperature. SI This law of course applies to each layer of the globe, and thus to its mean temperature, and is’ obviously general for all gaseous celestial bodies condensing under ‘the law of gravitation. Some persons who do not fully understahd*the problem under consideration have ‘asserted thatthe functions. which express the distribution-of density and temperature with respect to the radius, are altered by shrinkage, ’so ‘that the! law then breaks down, or «rather is not proved to hold true. It is perhaps worth while to show the error-of this'view, ‘ Lord Kelvin: has shown (Ph2/. Mag., 1887, p. 287) that the temperature distribution throughout the globe must satisfy the differential equation a Tails ae : a0, 6° where @ is the temperature, x a function of the radius, and « a constant. | If @=(v) be a particular solution of this equation, the second differential coefficients ox) = — oe)er 4, and P'(mx)= — {p(mx)\ea tad and the general solution is shown to be of the form 6=Co{xC- i(k), where C and « are constants. Under convective equilibrium the mass will contract in such a way that the particles in any concentric sphere surface do not penetrate those surfaces adjacent, that is, the new ordinate & of any particle is defined by the equation f=ax, where a is a numerical coefficient smaller than unity ; and hence 8=CpleC-(«)} . will be a solution of exactly the same form as the first... A curve defined by the equation V=¥(7) will give the absolute temperature from the centre to the surface. In like manner another curve n=(7")\* will give the distribution of density with respect to the radius. Shrinkage by which the variables become p=ar will not change the character of these two functions; and hence the distribution of density and temperature is rigorofisly the same after contraction as before. This result continues to hold so long as the body is wholly gaseous and obeys the laws of con- vective equilibrium, Prof. Perry has examined at some length the question of radi- ation, and he deserves our thanks for the interesting suggestions he has advanced. Yet I have considered our knowledge based on terrestrial experiment too limited to furnish any conclusion which can be confidently applied to the conditions existing in the heavens, except that the masses are always in convective equilibrium, and that all shrinkage is determined by this condition. Accordingly the foregoing conclusions would seem to be valid generally. It seems fair to conclude that there are few branches of physical science which offer such an unexplored field as the one which relates to the life-history of stars. And though it may be assumed that forces are at work in space, of which we have little or no experimental analogy up to this time, yet it is always Safe to apply known laws to the phenomena of the heavens with a view of explaining observations, and of suggesting unknown causes which may become the subject of future research. PROS Jomskoies Washington, D.C., August 5. 520 ‘NATURE [SEPTEMBER 28, 1899 Remarkable Lightning Flashes. Last September you kindly published a photograph of a multiple lightning flash taken with a moving camera. I now enclose a photograph taken at Johannesburg by Mr. G. H. Preston. Ithink that he must have moved his camera (Frena) unintentionally, being startled at the commencement of a very vivid flash, which seems to have lasted some considerable time, say nearly one second. At any rate there are nine distinct lightning flashes, all of identical shape. The first three, or perhaps a few more, are very strong and close together, and possibly while they were taken the camera may as yet have been fairly stationary ; its axis then moved in spiral curves while the remaining six flashes imprinted themselves. The photograph is of interest on account of the large number of individual but otherwise identical flashes, and especially because it shows that these individual discharges follow each other at irregular intervals ; and I hope that the suggestion which I made last year to study this subject may be carried out. As on my last year’s photograph, there is on this one an addi- tional flash, which appears to be single but is much more branched than the other one. C. E. STROMEYER. Lancefield, West Didsbury, August 21. In NATURE for September 14 (p. 460), the writer on dark lightning refers to the absence of dark flashes in pictures of artificial discharge. I may perhaps draw the attention of any who are unfamiliar with Lord Armstrong’s ‘‘ Electric Move- ment in Air and Water”’ to Plate 34 in that book, in which is shown a very fine example of a dark flah. Lord Armstrong describes how he obtained the discharge on p. 41. Plate 18 is also of interest in this connection. HENRY STROUD. The Durham College of Science, Newcastle-upon-Tyne, September 18. I po not see on what grounds it is concluded (p. 423) that ribbon lightning has a real existence. The appearance might easily be caused by defective vision. If the fork is not distinctly focussed on the retina, it may appear either broadened or double or multiple, especially if there is any degree of cataract in the eye. The ribbon appearance in the photograph shown in your article is surely to be explained by the camera having been moved downwards and slightly to the right, or else in the op- posite direction, and three or more discharges having taken place during thetime. The horizon not being sharp is further evidence. One may imagine, however, that an appearance of this kind might also arise from a discharge being repeated through the same air, but the air moving bodily between one discharge and the next: it seems to me it yet remains to be proved whether such a thing ever does occur. One would sup- that if it did, the motion of the air would not be uniform throughout the flash, and therefore the ribbon would be unequal in width in different parts. NO. 1561, VOL. 60] pose With regard to apparently black lightning, some months ago I saw a black fork having exactly the appearance of an ordinary flash of forked lightning, only dark on the light ground ofa flash of sheet lightning. I concluded the explanation to be that given by Lord Kelvin, only the curious circumstance was that I did not remember I had previously seen a bright fork of the pattern of the dark one. I haveno doubt, however, that there must have been one, and that my being dazzled by it caused me to see it again, dark, as soon as there was a light background to show it. T. W. BACKHOUSE. West Hendon House, Sunderland, September 18. Ir is surprising that such a brilliant experimentalist as Prof. R. W. Wood does not allude to that peculiar reversal of the photographic image known as the Clayden effect. I drew particular attention to this explanation of the dark flash in a lecture before the Royal Photographic Society this year, which is fully reported and illustrated in the Photographic Journal for March last. The Clayden effect is easily verified in the following way. Arrange the sparking terminals of a coil, horizontally, about four inches apart, with a dark background of velvet ; focus a camera for the sparks, then darken the room. Place a strip of white card one inch. wide near one terminal in the spark gap, uncap the lens, and expose on the card by burning one inch of magnesium wire ; then remove the card and pass a spark, now place the same card near the other terminal of the spark gap, and burn another inch of magnesium wire. On developing the plate it will be found that the spark image is reversed over the latter card only. ‘This shows that the same amount of iog has a very different effect, whether it is deposited before or after the image. It must sometimes happen that in photographing lightning some | sky fog or other fog will be deposited after the image ; it therefore seems highly probable that any bright flash could be converted into a dark flash by slightly fogging the plate before development. The Clayden effect also explains why, with a number of flashes on the same plate, some may be dark and some light, and yet dark lightning probably has no real existence. 156 Clapham Road, S.W. F. H. GLew. Sedge-Warblers seizing Butterflies. OBSERVED instances of birds capturing butterflies are so few that I venture to think the following worth putting on record. On the evening of August 12, at about 6.30 p.m., I was walking beside a dyke on Ludham Marsh, Norfolk, when my attention was attracted by the alarm notes of a pair of sedge-warblers in the reeds. I stood still, and soon caught sight of both birds within about six yards of ne. Each had a butterfly in its mouth, and with my field-glass I was able to identify the species as a meadow brown (Z. _/aniva) and a small white (P. rafae). From the behaviour of the birds, and my observation of them on subsequent days, I have no doubt that they were feeding their nestlings, though I was unable to find the nest. I may add that at the time most of the butterflies had taken up their quarters for the night on stems of reeds, &c., and that very many of the butterflies which I observed during the daytime on the marshes had very ragged and chipped wings. These injuries may have been caused by wind and contact with twigs, thorns, &c., but they were quite compatible with repeated ineffectual pecks and snips from the beaks of small birds. OswaLp H. LATTER. Charterhouse, Godalming, September 17. Explosion of Aluminium Iodide. T HAD two samples of aluminium iodide in two hermetically sealed glass tubes sent by a German firm. One of them was passing round the class, and the other was lying on the demon- stration table. Suddenly a report was heard, and I found that the tube on the table had exploded, and its contents had been thrown out. Both the tubes were perfectly sound, and therefore there seems to be no reason to suspect that the volatile com- pound found an explosive mixture with the air. The temper- ature of the lecture room was at the time nearly 95° F. I com- municate this matter to you to find out if others have had similar experience with aluminium iodide P. L, NARASU. Christian College, Madras, July 30. SEPTEMBER 28, 1899] NATURE 521 THE DOVER MEETING OF THE BRITISH ASSOCIATION. ape final meeting of the general committee of the British Association was held on Wednesday in last week, for the purpose of receiving the report of the committee of recommendations. The list of grants made for various scientific purposes has already been given (p. 496). The committee also recommended that, in view of the opportunities of ethnographic inquiry which will be presented by the Indian census now beginning, the council of the Association be requested to urge the Government of India to make use of the census officers to obtain information with reference to particular races and tribes, and to attach photographers to the census officers to furnish a complete photographic series of typical specimens of the various races, of views of archaic industries, and of other facts interesting to ethnologists. This recommendation was accepted and ordered to be forwarded to the council. It was also resolved that the council be requested to recommend to Her Majesty’s Govérnment the importance of giving more prominence to botany in the training of Indian forest officers. At the concluding general meeting of the Association, held on Wednesday, September 20, it was announced that the number of tickets issued was 1403. The usual votes of thanks were then put to the meeting and passed. | Sir G. G. Stokes proposed :—“ That the best thanks of the Association be given to the Mayor and Corporation, to the local committee, and to the officers of the local sub-committees for their reception of the Association.” Prof. Forsyth, in seconding the resolution, said that they should all carry away grateful recollections of the | way in which they had been treated at Dover, and if the meeting had not been the largest it had certainly been very pleasant and highly successful. The two local secretaries, Colonel Knocker and Mr. W. H. Pendlebury, responded for the local committee. Sir John Evans proposed a vote of thanks to the President, Council, and Headmaster of Dover College | for putting the college buildings at the service of the Association. In seconding the resolution Sir W. Thisel- ton-Dyer expressed, on behalf of the members of the Association, gratitude to the municipality and inhabitants of Dover for the reception which they had given to the Association. Some of the work this year had been of quite exceptional importance. The Headmaster of Dover College (the Rev. W. C. Compton) acknowledged the vote of thanks. Sir Norman Lockyer proposed a vote of thanks to Captain Winslow and the other officers of Her Majesty’s | ships, to Major-General Sir Leslie Rundle and Staff, and to all the inhabitants who had entertained members or conducted excursions, and to the heads of firms who had thrown open their works. He remarked that the fact that this vote of thanks included officers of Her Majesty’s Navy and Army gave distinction to a meeting which otherwise had a distinctive character. members of the Association had met in the Sections to- gether with French coz/fréres, and the visit of the French Association had been marked by many little incidents showing a kindly feeling, which was national rather than local. Sir W. H. White seconded the resolution, and Dr. Sebastian Evans briefly responded. Sir John Murray moved that a cordial vote of thanks be given to Sir Michael Foster for his services as president of the Dover meeting. Sir A. Binnie, in seconding the resolution, said that the success of this meeting was largely due to the tact and urbanity of the president. Sir Michael Foster in a few words acknowledged the compliment, and then declared the meeting adjourned till next September at Bradford. NO. 1561, VOL. 60] For the first time | On Wednesday afternoon the Mayor and Corporation of Canterbury received and entertained at luncheon the president and some of the chief officers of the Association, together with the president, Dr. Brouardel, and about a hundred members of l’Association frangaise pour l’avance- ment des sciences A brief toast list followed the luncheon. The Queen and the President of the French Republic having been successively proposed from the chair, Dean Farrar gave “Our Guests and Success to the British and French Associations for the Advancement of Science,” coupling with it the names of the presidents of the two Associa « uons. In the course of his remarks he said there was no means of human knowledge which the human mind could devote itself to study with more profit or advantage than the knowledge of science. ‘It was right to do honour to those whose efforts had illuminated darkness, removed ignorance and extended man’s horizon. Dr. Brouardel and Sir Michael Foster responded. On Thursday, September 21, the president, officials and about three hundred members of the British Associ- ation proceeded from Dover to Boulogne to return the visit of the French Association. From the 77zwes report we learn that at Boulogne they were received by leading members of the French Association, who entertained them to breakfast, and afterwards they were officially welcomed at the Town Hall by the Mayor of Boulogne. Later in the day they were entertained at’ a banquet in | the ball-room of the casino by the municipality of the town, and speeches of compliment and welcome were delivered by the Prefect of the Pas de Calais, the Director of Primary Education as delegate of the French Government, Sir. Michael. Foster and Dr, Brouardel. Special commemorative medals were presented by the French Association to their president and Sir M. Foster. Subsequently the visitors were present at the unveiling of amonument of Dr. Duchesne—who died about twenty- five years ago and was distinguished by his application of electricity to nervous disorders—and of a black marble plaque upon the house in which Thomas Campbell, the poet (who devoted much time and attention to many public matters, including the University of London), died at Boulogne in 1844. No account of the meeting which has just been con- cluded would be complete without a reference to two sermons on “Some of the Mutual Influences of Theology and the Natural Sciences,” preached in St. Mary’s Church for members of the Association by the Ven. J. M. Wilson, Archdeacon of Manchester. The en- larged conception of the study of theology, as_pre- sented by Archdeacon Wilson, will be made the subject of deep consideration by many thoughtful minds ; and men of science cannot but be gratified at the liberal spirit which permeated it. No longer is it asserted that the methods and results of theology and science are antagonistic, but rather that the two exert beneficial influences upon each other, and that the scientific method should be applied to theological research. The expression of such rational views should do much to overcome the prejudice which still exists against scientific habits of thought, and to create sympathy between men engaged in advancing natural and theological knowledge. The common meeting ground is the search for truth, so far as the human mind can follow it. SECTION E. GEOGRAPHY, OPENING ADDRESS BY SIR JOHN Murray, K.C.B., F.R.3., LL.D., PRESIDENT OF THE SECTION, In his opening Address to the members of the British | Association at the Ipswich meeting, the President cast a retro- spective glance at the progress that had taken place in the several branches of scientific inquiry from the time of the form- ation of the Association in 1831 down to 1895, the year in which 522 were published the last two of the fifty volumes of Reports con- taining the scientific results of the voyage of H.M.S. Chal/enger. In that very able and detailed review there is no reference whatever to the work of the numerous expeditions which had been fitted out by this and other countries for the exploration of the depths of the sea, nor is there any mention of the great advance in our knowledge of the ocean during the period of sixty-five years then under consideration. This omission may be accounted for by the fact that, at the time of the formation of the British Association, knowledge concerning the ocean was, literally speaking, superficial. The study of marine phenomena had hitherto been almost entirely limited to the ‘surface and shallow waters of the ocean, to the survey of coasts and of oceanic routes directly useful for commercial purposes. Down to that time there had been no systematic attempts to ascertain the physical and biological conditions of those regions of the earth’s surface covered by the deeper waters of the ocean ; indeed, most of the apparatus necessary for such investigations had not yet been invented. The difficulties connected with the exploration of the greater depths of the sea arise principally from the fact that, in the majority of cases, the observations are necessarily indirect. At the surface of the ocean direct observation is possible, but our knowledge of the conditions prevailing in deep water, and of all that is there taking place, is almost wholly dependent on the correct working of instruments, the action of which at the critical moment is hidden from sight. It was the desire to establish telegraphic communication between Europe and America that gave the first direct impulse to the scientific exploration of the great ocean-basins, and at the present day the survey of new cable routes still yields each year a large amount of accurate knowledge regarding the floor of the ocean. Immediately before the Challenger Expedition there was a marked improvement in all the apparatus used in marine investigations, and thus during the Challenger Expedition the great ocean-basins were for the first time systematically and successfully explored, This expedition, which lasted for nearly four years, was successful beyond the expectations of its pro- moters, and opened out a new era in the study of oceanography. A great many sciences were enriched by a grand accumulation of new facts. Large collections were sent and brought home, and were subsequently described by specialists belonging to almost every civilised nation. Since the Challenger Expedition there has been almost a revolution in the methods employed in deep-sea observations. The most profound abysses of the ocean are now being everywhere examined by sailors and scientific men with increasing precision, rapidity and success. The recognition of oceanography as a distinct branch of science may be said to date from the commencement of the Challenger investigations. The fuller knowledge we now possess about all oceanic phenomena has had a great modifying influence on many general conceptions as to the nature and ex- tent of those changes which the crust of the earth is now under- going and has undergone in past geological times. Our knowledge of the ocean is still very incomplete. So much has, however, already been acquired that the historian will, in all probability, point to the oceanographical discoveries during the past forty years as the most important addition to the natural knowledge of our planet since the great geographical voyages associated with the names of Columbus, Da Gama, and Magellan, at the end of the fifteenth and the beginning of the sixteenth centuries. It is not my intention on this occasion to attempt anyth ng like a general review of the present state of oceanographic science. But, as nearly all the samples of marine deposits col- lected during the past thirty years have passed. through my hands, I shall endeavour briefly to point out what, in general, their detailed examination teaches with respect to the present condition of the floor of the ocean, and I will thereafter indicate what appears to me to be the bearing of some of these results on speculations as to the evolution of the existing surface features of our planet. Depth of the Ocean, All measurements of depth, by which we ascertain the relief of that part of the earth’s crust covered by water, are referred to the sea-surface ; the measurements of height on the land are likewise referred to sea-level. It is admitted that the ocean has a very complicated undulating surface, in consequence of the attraction which the heterogeneous and elevated portions NO. 1561, VOL. 60] NATURE [SEPTEMBER 28, 1899 of the lithosphere exercise on the liquid hydrosphere. In the opinion of geodesists the geoid may in some places depart from the figure of the spheroid by 1000 feet. Still it is not likely that this surface of the geoid departs so widely from the mean ellipsoidal form as to introduce a great error into our estimates of the elevations and depressions on the surface of the lithosphere. The soundings over the water-surface of the globe have ac- cumulated at a rapid rate during the past fifty years. In the shallow water, where it is necessary to know the depth for purposes of navigation, the soundings may now be spoken of as innumerable ; the 100-fathom line surrounding the land can therefore often be drawn in with much exactness. Compared with this shallow-water region, the soundings in deep water beyond the 100-fathom line are much less numerous ; each year, however, there are large additions to our knowledge. Within the last decade over ten thousand deep soundings have been taken by British ships alone. The deep soundings are scattered over the different ocean-basins in varying proportions, being now most numerous in the North Atlantic and South-west Pacific, and in these two regions the contour-lines of depth may be drawn in with greater confidence than in the other divisions of the great ocean-basins. It may be pointed out that 659 soundings taken quite recently during cable surveys in the North Atlantic, although much closer together than is usually the case, and yielding much detailed information to cable engineers, have, from a general point of view, necessitated but little alteration in the contour- lines drawn on the Challenger bathymetrical maps published in 1895. Again, the recent soundings of the German s.s. Valdivia in the Atlantic, Indian, and Southern Oceans have not caused very great alteration in the positions of the contour-lines on the Challenger maps, if we except one occasion in the South Atlantic when a depth of 2000 fathoms was expected and the sounding machine recorded a depth of only 536 fathoms, and again in the great Southern Ocean when depths exceeding 3000 fathoms were obtained in a region where the contour-lines indicated between 1000 and 2000 fathoms. This latter discovery suggests that the great depth recorded by Ross to the south-east of South Georgia may not be very far from the truth. I have redrawn the several contour-lines of depth in the great ocean-basins, after careful consideration of the most recent data, and these may now be regarded as a somewhat close ap- proximation to the actual state of matters, with the possible exception of the great Southern and Antarctic Oceans, where there are relatively few soundings, but where the projected Antarctic Expeditions should soon be at work. On the whole, it may be said that the general tendency of recent soundings is to extend the area with depths greater than 1000 fathoms, and to show that numerous volcanic cones rise from the general level of the floor of the ocean-basins up to various levels beneath the sea-surface. The areas marked out by the contour-lines of depth are now estimated as follows :— Fms. Sq. geo. m. Per cent. Between the shore and 100 7,000,000 ... (or 7 of the sea-bed) 5 100 ,, 1000 10,000,000 (or 10 ,, oA ) SS 1000 .,, 2000 22,000,000 (or 2t ,, nr ) a 2000 ,, 3000 57,000,000 (or 55 55 cf ) Over 3000 fathoms 7,000,000 ... (Or 7 55 > ) 103,000,000 100 From these results it appears that considerably more than half of the sea-floor lies at a depth exceeding 2000 fathoms, or over two geographical miles. It is interesting to note that the area within the 1o0o-fathom line occupies 7,000,000 square geo- graphical miles, whereas the area occupied by the next succeed- ing 900 fathoms (viz. between 100 and 1000 fathoms) occupies only 10,000,000 square geographical miles. This points to a relatively rapid descent of the sea-floor along the continental slopes between 100 and 1000 fathoms, and therefore confirms the results gained by actual soundings in this region, many of which indicate steep inclines or even perpendicular cliffs. Not only are the continental slopes the seat of many deposit-slips and seismic disturbances, but Mr. Benest has given good reasons for believing that underground rivers sometimes enter the sea at depths beyond 100 fathoms, and there bring about sudden changes in deep water. Again, the relatively large area covered by the continental shelf between the shore-line ‘and too fathoms points to the wearing away of the land by current and wave action. On the Chad/enger charts all areas where the depth exceeds SEPTEMBER 28, 1899] NATURE 3000 fathoms have been called ‘‘ Deeps,” and distinctive names have been conferred upon them. Forty-three such depressions are now known, and the positions of these are shown on the map here exhibited ; twenty-four are situated in the Pacific Ocean, three in the Indian Ocean, fifteen in the Atlantic Ocean, and one in the Southern and Antarctic Oceans. The area occupied by these thirty-nine deeps is estimated at 7,152,000 square geographical miles, or about 7 per cent. of the total water-surface of the globe. Within these deeps over 250 soundings have been recorded, of which twenty-four exceed 4000 fathoms, including three exceeding 5000 fathoms. Depths exceeding 4000 fathoms (or four geographical miles) have been recorded within eight of the deeps, viz. in the North Atlantic within the Nares Deep; in the Antarctic within the Ross Deep ; in the Banda Sea within the Weber Deep; in the North Pacific within the Challenger, Tuscarora, and Supau Deeps ; and in the South Pacific within the Aldrich and Richards Deeps. Depths exceeding 5000 fathoms have been hitherto re- corded only within the Aldrich Deep of the South Pacific, to the east of the Kermadecs and Friendly Islands, where the greatest depth is 5155 fathoms, or 530 feet more than five geographical miles, being about 2000 feet more below the level of the sea than the summit of Mount Everest in the Himalayas is above it. The levels on the surface of the lithosphere thus oscillate between the limits of about ten geographical miles (more than eighteen kilometres). Temperature of the Ocean-floor. Our knowledge of the temperature on the floor of the ocean is derived from observations in the layers of water immediately above the bottom by means of deep-sea thermometers, from the electric resistance of telegraph cables resting on the bed of the great ocean-basins, and from the temperature of large masses of mud and ooze brought up by the dredge from great depths. These observations are now sufficiently numerous to permit of some general statements as to the distribution of temperature over the bottom of the great oceans. All the temperatures recorded up to the present time in the sub-surface waters of the open ocean indicate that at a depth of about 100 fathoms seasonal variation of temperature disappears. Beyond that depth there is a constant, or nearly constant, tem- perature at any one place throughout the year. In some special positions, and under some peculiar conditions, a lateral shift- ing of large bodies of water takes place on the floor of the ocean at depths greater than 100 fathoms. This phenomenon has been well illustrated by Prof. Libbey off the east coast of North America, where the Gulf Stream and Labrador Current run side by side in opposite directions. This lateral shifting can- not, however, be called seasonal, for it appears to be effected by violent storms, or strong off-shore winds bringing up colder water from considerable depths to supply the place of the sur- face drift, so that the colder water covers stretches of the ocean’s bed which under normal conditions are overlaid by warmer strata of water. Sudden changes of temperature like these cause the destruction of innumerable marine animals, and pro- duce very marked peculiarities in the deposits over the areas thus affected. It is estimated that 92 per cent. of the entire sea-floor has a temperature lower than 40° F. This is in striking contrast to the temperature prevailing at the surface of the ocean, only 16 per cent. of which has a mean temperature under 40° F. The temperature over nearly the whole of the floor of the Indian Ocean in deep water is under 35° F. A similar temperature occurs over a large part of the South Atlantic and certain parts of the Pacific, but at-the bottom of the North Atlantic basin and over a very large portion of the Pacific the temperature is higher than 35° F. In depths beyond. 2000 fathoms, the average temperature over the floor of the North Atlantic is about 2° F, above the average temperature at the bottom of the Indian Ocean and South Atlantic, while the average tem- perature of the bed of the Pacific is intermediate between these. It is admitted that the low temperature of the deep sea has been acquired at the surface in Polar and sub-Polar regions, chiefly within the higher latitudes of the southern hemisphere, where the cooled surface water sinks to the bottom and spreads slowly over the floor of the ocean into equatorial regions. These cold waters carry with them into the deep sea the gases of the atmosphere, which are everywhere taken up. at ithe surface according to the known laws of gas absorption. In this way myriads of living animals are enabled to carry on their existence NO. 1561, VOL. 60] 523 at all depths in the open ocean. The nitrogen remains more or less constant at all times and places, but the proportion of oxygen is frequently much reduced in deep water, owing to the processes of oxidation and respiration which are there going on. The deep sea is a region of darkness as well as of low tem- perature, for the direct rays of the sun are wholly absorbed in passing through the superficial layers of water. Plant-life is in consequence quite absent over 93 per cent. of the bottom of the ocean, or 66 per cent. of the whole surface of the lithosphere. The abundant deep-sea fauna, which covers the floor of the ocean, is therefore ultimately dependent for food upon organic matter assimilated by plants near its surface, in the shallower waters near the coast-lines, and on the surface of the dry land itself. As has been already stated, about 7,000,000 square geo- graphical miles of the sea-floor lies within the 1o0-fathom line, and this area is in consequence subject to seasonal variations of temperature, to strong currents, to the effects of sunlight, and presents a great variety of physical conditions. The planktonic plant-life is here reinforced by the littoral sea-weeds, and animal- life is very abundant. About 40 per cent. of the water over the bottom of this shallow-water area has a mean temperature under 40° F., while 20 per cent. has a mean temperature between 40° and 60° F., and 40 per cent. a temperature of over 60° F. It follows from this that only 3 per cent. of the floor of the ocean presents conditions of temperature favourable for the vigorous growth of corals and those other benthonic organisms which make up coral reefs and require a temperature of over 60° F. all the year round. On the other hand, more than half of the surface of the ocean has a temperature which never falls below 60° F. at any time of the year. In these surface-waters with a high temperature, the shells of Pelagic Molluscs, Foram- inifera, Algee, and other planktonic organisms are secreted in great abundance, and fall to the bottom after death. It thus happens that, at the present time, over nearly the whole floor of the ocean we have mingled in the deposits the remains of organisms which had lived under widely different physical conditions, since the remains of organisms which lived in tropical sunlight, and in water ata temperature above 80° F., all their lives, now lie buried in the same deposit on the sea- floor together with the remains of other organisms which lived all their lives in darkness and at a temperature near to the freezing point of fresh water. Marine Deposits on the Ocean-floor. The marine deposits now forming over the floor of the ocean present many interesting peculiarities according to their geo- graphical and bathymetrical position. On the continental shelf, within the 1oo-fathom line, sands and gravels pre- dominate, while on the continental slopes beyond the I0o- fathom line, Blue Muds, Green Muds, and Red Muds, together with Volcanic Muds and Coral Muds, prevail, the two latter kinds of deposits being, however, more characteristic of the shallow water around oceanic islands. The composition of all these Terrigenous Deposits depends on the structure of the adjoining land. Around continental shores, except where coral reefs, limestones, and volcanic rocks are present, the materials consist principally of fragments and minerals derived from the disintegration of the ancient rocks of the continents, the most characteristic and abundant mineral species being quartz. River detritus extends in many instances far from the land, while off high and bold coasts, where no large rivers enter the sea, pelagic conditions may be found in somewhat close prox- imity to the shore-line, Itis in these latter positions that Green Muds containing much glauconite, and other deposits containing many phosphatic nodules, have for the most part been found ; as, for instance, off the eastern coast of the United States, off the Cape of Good Hope, and off the eastern coasts of Australia and Japan. The presence of glauconitic grains and phosphatic nodules in the deposit at these places appears tc be very intimately associated with a great annual range of temperature in the surface and shallow waters, and the consequent destruction of myriads of marine animals. As an example of this phenomenon may be mentioned the destruction of the tile-fish in the spring of 1882 off the eastern coast of North America, when a layer six feet in thickness of dead fish and other marine animals was believed to cover the océan floor for many square miles. Inall the Terrigenous Deposits the evidences of the mechanical action of tides, of currents, and of a great variety of physical conditions, may almost everywhere be detected, and it is possible 524 NATURE [SEPTEMBER 28, 1899 to recognise in these deposits an accumulation of materials analogous to many of the marine stratified rocks of the con- tinents, such as sandstones, quartzites, shales, marls, greensands, chalks, limestones, conglomerates, and volcanic grits. With increasing depth and distance from the continents the deposits gradually lose their terrigenous character, the particles derived directly from the emerged land decrease in size and in number, the evidences of mechanical action disappear, and the deposits pass slowly into what have been called Pelagic De- posits at anaverage distance of about 200 miles from continental coast-lines. The materials composing Pelagic Deposits are not directly derived from the disintegration of the continents and other land-surfaces. They are largely made up of the shells and skeletons of marine organisms secreted in the surface waters of the ocean, consisting either of carbonate of lime, such as Pelagic Molluses, Pelagic Foraminifera, and Pelagic Algze, or of silica, such as Diatoms and Radiolarians. The inorganic constituents of the Pelagic Deposits are for the most part derived from the attrition of floating pumice, from the disintegration of water- logged pumice, from showers of volcanic ashes, and from the débris ejected from submarine volcanoes, together with the pro- ducts of their decomposition. Quartz particles, which play so important a 7é/e in the Terrigenous Deposits, are almost wholly absent, except where the surface waters of the ocean are affected by floating ice, or where the prevailing winds have driven the desert sands far into the oceanic areas. Glauconite is likewise absent from these abysmal regions. The various kinds of Pelagic Deposits are named according to their characteristic constituents, Pteropod Oozes, Globigerina Oozes, Diatom Oozes, Radiolarian Oozes, and Red Clay. The distribution of the deep-sea deposits over the floor of the ocean is shown on the map here exhibited, but it must be re- membered that there is no sharp line of demarcation between them ; the Terrigenous pass gradually into the Pelagic Deposits, and the varieties of each of these great divisions also pass in- sensibly the one into the other, so that it is often difficult to fix the name of a given sample. On another map here exhibited the percentage distribution of carbonate of lime in the deposits over the floor of the ocean has been represented, the results being founded on an extremely large number of analyses. The results are also shown in the following table :— Sq. Geo. Miles. Percentage. Over 75% CaCO, 6,000,000 58 5o\to 75% 5; 24,000,000 23°2 Pic) “Coys 14,000,000 13°5 Wnder 25/405, 59,000,000 575 103,000,000 100 The carbonate of lime shells derived from the surface play a great and puzzling vé/e in all deep-sea deposits, varying in abundance according to the depth of the ocean and the temper- ature of the surface waters. In tropical regions removed from land, where the depths are less than 600 fathoms, the carbonate of lime due to the remains of these organisms from the surface may rise to 80 or 90 per cent. ; with increase of depth, and under the same surface conditions, the percentage of carbonate of lime slowly diminishes, till, at depths of about 2000 fathoms, the average percentage falls to about 60, at 2400 fathoms to about 30, and at about 2600 fathoms to about 10, beyond which depth there may be only traces of carbonate of lime due to the presence of surface shells. The thin and more delicate surface shells first disappear from the deposits, the thicker and denser ones alone persist to greater depths. A careful examination of a large number of observations shows that the percentage of carbonate of lime in the deposits falls off much more rapidly at depths between 2200 and 2500 fathoms than at other depths. The Red Clay, which occurs in all the deeper stretches of the ocean far from land, and covers nearly half of the whole sea- floor, contains—in addition to volcanic débris, clayey matter, the oxides of iron and manganese—numerous remains of whales, sharks and other fishes, together with zeolitic crystals, man- ganese nodules, and minute magnetic spherules, which are be- lieved to have a cosmic origin. One hawl of a small trawl in the Central Pacific brought to the surface on one occasion, from a depth of about two and a half miles, many bushels of man- ganese nodules, along with fifteen hundred sharks’ teeth, over fifty fragments of earbones and other bones of whales. Some of these organic remains, such as the Carcharodon and Lamna NO. 1561, VOL. 60] teeth and the bones of the Ziphioid whales, belong apparently to extinct species. One or two of these sharks’ teeth, ear- bones, or cosmic spherules, may be occasionally found in a Globigerina Ooze, but their occurrence in this or any deposits other than Red Clay is extremely rare. Our knowledge of the marine deposits is limited to the super- ficial layers; as a rule, the sounding-tube does not penetrate more than six or eight inches, but in some positions the sound- ing-tube and dredge have been known to sink fully two feet into the deposit. Sometimes a Red Clay is overlaid by a Globigerina Ooze, more frequently a Red Clay overlies a Glob- igerina Ooze, the transition between the two layers being either abrupt or gradual. In some positions it is possible to account for these layers by referring them to changes in the condition of the surface waters, but in other situations it seems necessary to call in elevations and subsidences of the sea-floor. If the whole of the carbonate of lime shells be removed by dilute acid from a typical sample of Globigerina Ooze, the inorganic residue left behind is quite similar in composition to a typical Red Clay. This suggests that possibly, owing to some hypogene action, such as the escape of carbonic acid through the sea-floor, a deposit that once was a Globigerina Ooze might be slowly converted into a Red Clay. However, this is not the interpretation which commends itself after an ex- amination of all the data at present available ; a consideration of the rate of accumulation probably affords a more correct interpretation. It appears certain that the Terrigenous Deposits accumulate much more rapidly than the Pelagic Deposits. Among the Pelagic Deposits, the Pteropod and Globigerina Oozes of the tropical regions, being made up of the calcareous shells of a much larger number of tropical species, apparently accumulate at a greater rate than the Globigerina Oozes in extra-tropical areas. Diatom Ooze being composed of both calcareous and siliceous organisms, has again a more rapid rate of deposition than Radiolarian Ooze. In Red Clay the mini- mum rate of accumulation takes place. The number of sharks’ teeth, of earbones and other bones of Cetaceans and of cosmic spherules in a deposit may indeed be taken as a measure of the rate of deposition. These spherules, teeth and bones are probably more abundant in the Red Clays, because few other substances there fall to the bottom to cover them up, and they thus form an appreciable part of the whole deposit. The volcanic materials in a Red Clay having, because of the slow accumulation, been for a long time exposed to the action of sea~ water, have been profoundly altered. The massive manganese- iron nodules and zeolitic crystals present in the deposit are secondary products arising from the decomposition of these volcanic materials, just as the formation of glauconite, phosphatic, and calcareous and barytic nodules accompanies the decomposition of terrigenous rocks and minerals in deposits nearer continental shores. There is thus a striking difference between the average chemical and mineralogical composition of Terrigenous and Pelagic Deposits. It would be extremely interesting to have a detailed examin- ation of one of those deep holes where a typical Red Clay is present, and even to bore some depth into such a deposit if possible, for in these positions it is probable that not more than a few feet of deposit have accumulated since the close of the Tertiary period. One such area lies to the south-west of Australia, and its examination might possibly form part of the programme of the approaching Antarctic explorations. Life on the Ocean-floor. It has already been stated that plant-life is limited to the shallow waters, but fishes and members of all the invertebrate groups are distributed over the floor of the ocean at all depths. The majority of these deep-sea animals live by eating the mud, clay or ooze, or by catching the minute particles of organic matter which fall from the surface. It is probably not far from the truth to say that three-fourths of the deposits now covering the floor of the ocean have passed through the alimentary canals of marine animals. These mud-eating species, many of which are of gigantic size when compared with their allies living in the shallow coastal waters, become in turn the prey of numerous rapacious animals armed with peculiar prehensile and tactile organs. Some fishes are blind, while others have very large eyes. Phosphorescent light plays a most important 7é/e in the deep sea, and is correlated with the prevailing red and brown colours of deep-sea organisms. Phosphorescent organs appear sometimes to act asa bull’s-eye lantern to enable particles of SEPTEMBER 28, 1899] food to be picked up, and at other times as a lure or a warning. All these peculiar adaptations indicate that the struggle for life may be not much less severe in the deep sea than in the shallower waters of the ocean. Many deep-sea animals present archaic characters ; still the deep sea cannot be said to contain more remnants of faunas which flourished in remote geological periods than the shallow and fresh waters of the continents. Indeed, king-crabs, Lingulas, Trigonias, Port Jackson sharks, Cevatodus, Lepido- siren, and Protofterus, probably represent older faunas than anything to be found in the deep sea Sir Wyville Thomson was of opinion that, from the Silurian period to the present day, there had been as now a continuous deep ocean with a bottom temperature oscillating about the freezing point of fresh water, and that there had always been an abyssal fauna. I incline to the view that in Paleozoic times the ocean-basins were not so deep as they are now; that the ocean then had throughout a nearly uniform high temperature, and that life was either absent or represented only by bacteria and other low forms in great depths, as is now the case in the Black Sea, where life is practically absent beyond roo fathoms, and where the deeper waters are saturated with sulphuretted ‘hydrogen. This is not, however, the place to enter on specu- lations concerning the origin of the deep-sea fauna, nor to dwell on what has been called ‘‘ bipolarity”’ in the distribution of marine organisms. Evolution of the Continental and Oceantc Areas. I have now pointed out what appears to me to be some of the more general results arrived at in recent years regarding the present condition of the floor of the ocean. I may now be permitted to indicate the possible bearing of these results on opinions as to the origin of some fundamental geographical phenomena ; for instance, on the evolution of the protruding continents and sunken ocean-basins. In dealing with such a problem much that is hypothetical must necessarily be intro- duced, but these speculations are based on ascertained scientific facts. The well-known American geologist, Dutton, says: ‘‘It has been much the habit of geologists to attempt to explain the pro- gressive elevation of plateaus and mountain platforms, and also the folding of strata, by one and the same process. I hold the two processes to be distinct, and having no necessary relation to each other. There are plicated regions which are little or not at all elevated, and there are elevated regions which are not plicated.” Speaking of great regional uplifts, he says further : ** What the real nature of the uplifting force may be is, to my mind, an entire mystery, but I think we may discern at least one of its attributes, and that it is a gradual expansion or a diminution of density of the subterranean magmas. . .. We know of no cause which could either add to the mass or diminish the density, yet one of the two must surely have happened. . . . Hence I infer that the cause which elevates the land involves an expansion of the underlying magmas, and the cause which depresses it is a shrinkage of the magmas ; the nature of the process is at present a complete mystery.” I shall endeavour to show how the detailed study of marine deposits may help to solve the mystery here referred to by Dutton. The surface of the globe has not always been as we now see it. When, in the past, the surface had a temperature of about 400° F., what is now the water of the ocean must have existed as water vapour in the atmosphere, which would thereby—as well as because of the presence of other substances—be increased in density and volume. Life, as we know it, could not then exist. Again, science foresees a time when low temperatures, like those produced by Prof. Dewar at the Royal Institution, will prevail over the face of the earth. The hydrosphere and atmosphere will then have disappeared within the rocky crust, or the waters of the ocean will have become solid rock, and over their surface will roll an ocean of liquid air about forty feet in depth. Life, as we know it, unless it undergoes suitable secular modifications, will be extinct. Somewhere between these two indefinite points of time in the evolution of our planet it is our privilege to live, to investigate, and to speculate concerning the antecedent and future conditions of things. When we regard our globe with the mind’s eye, it appears at the present time to be formed of concentric spheres, very like, and still very unlike, the successive coats of an onion. Within is situated the vast nucleus or cextrosphere ; surrounding this is what may be called the ¢e/osphere (tnxTds, molten), a NO. 1561, VOL. 60] NATURE 525) shell of materials in a state bordering on fusion, upon which rests and creeps the /zthosphere. Then follow hydrosphere and atmosphere, with the included dzosphere (Bios, life). To the interaction of these six geospheres, through energy derived from internal and external sources, may be referred all the existing superficial phenomena of the planet. The vast interior of the planetary mass, although not under direct observation, is known, from the results of the astronomer and physicist, to have a mean density of 5°6, or twice that of ordinary surface rock. The substances brought within the reach of observation in veinstones, in lavas, and hypogene rocks—by the action of water as a solvent and sublimant— warrant the belief that the centrosphere is largely made up of metals and metalloids with imprisoned gases. It is admitted that the vast nucleus has a very high temperature, but so enor- mous is the pressure of the superincumbent crust that the melting point of the substances in the interior is believed to be raised to a higher value than the temperature there existing— the centrosphere in consequence remains solid, for it may be assumed that the melting point of rock-forming materials is raised by increase of pressure. Astronomers, from a study of precession and nutation, have long been convinced that the centrosphere must be practically solid. Recent seismological observations indicate the transmission of two types of waves through the earth—the condensational- rarefactional and the purely distortional—and the study of these tremors supports the view that the centrosphere is not only solid, but possesses great uniformity of structure. The seis- mological investigations of Profs. Milne anid Knott point also to a fairly abrupt boundary or transition surface, where the solid nucleus passes into the somewhat plastic magma on which the firm upper crust rests. In this plastic layer or shell—named the ¢ehtosphere—the materials are most probably in a state of unstable equilibrium and bordering on fusion. Here the loose-textured solids of the external crust are converted into the denser solids of the nucleus or into molten masses, at a critical point of temperature and pressure; deep-seated rocks may in consequence escape through fissures in the lithosphere. Within the lithosphere itself, the temperature falls off so rapidly towards the surface as to be everywhere below the melting point of any substance there under its particular pressure. Now, as the solid centrosphere slowly contracted from loss of heat, the primitive lithosphere, in accommodating itself— through changes in the tektosphere—to the shrinking nucleus, would be buckled, warped, and thrown into ridges. That these movements are still going on is shown by the fact that the lithosphere is everywhere and at all times in a slight but measurable state of pulsation. The rigidity of the primitive rocky crust would spermit of considerable deformations of the kind here indicated. Indeed, the compression of mountain chains has most probably been brought about in this manner, but the same cannot be said of the elevation of plateaus, of mountain platforms, and of continents. From many lines of investigation it is concluded, as we have seen, that the centrosphere is homogeneous in structure. Direct observation, on the other hand, shows that the lithosphere is heterogeneous in composition. How has this heterogeneity been brought about? The original crust was almost certainly composed of complex and stable silicates, all the silicon dioxide being in combination with bases. Lord Kelvin has pointed out that, when the solid crust began to form, it would rapidly cool over its whole surface; the precipitation of water would accelerate this process, and there would soon be an approxim- ation to present conditions. As time went on the plastic or critical layer—the tektosphere—immediately beneath the crust would gradually sink deeper and deeper, while ruptures and re- adjustments would become less and less frequent than in earlier stages. With the first fall of rain the silicates of the crust would be attacked by water and carbon dioxide, which can at low temperatures displace silicon dioxide from its combinations. The silicates, in consequence, have been continuously robbed of a part, or the whole of their bases. The silica thus set free goes ultimately to form quartz veins and quartz sand on or about the emerged land, while the bases leached out of the disintegrating rocks are carried out into the ocean and ocean- basins. A continuous disintegration and differentiation of materials of the lithosphere, accompanied by a sort of migration and selection among mineral substances, is thus always in pro- gress. Through the agency of life, carbonate of lime accumulates 526 in one place; through the agency of winds, quartz sand is heaped up in another; through the agency of water, beds of clay, of oxides of iron and of manganese are spread out in other directions. The contraction of the centrosphere supplies the force which folds and crumples the lithosphere. The combined effect of hydrosphere, atmosphere and biosphere on the lithosphere gives direction and a determinate mode of action to that force. From the earliest geological times the most resistant dust of the continents has been strewn along the marginal belt of the sea- floor skirting the land. At the present time, the deposits over this area contain on the average about 70 per cent. of free and combined silica, mostly in the form of quartz sand. In the abysmal deposits far from land there is an average of only about 30 per cent. of silica, and hardly any of this in the form of quartz sand, Lime, iron and the other bases largely pre- dominate in these abysmal regions. The continuous loading on the margins of the emerged land by deposits tends by increased pressure to keep the materials of the tektosphere in a solid con- dition immediately beneath the loaded area. The unloading of emerged land tends by relief of pressure to produce a viscous condition of the tektosphere immediately beneath the denuded surfaces. Under the influence of the continuous shakings, tremors and tremblings always taking place in the lithosphere, the materials of the tektosphere yield to the stresses acting on them, and the deep-seated portions of the terrigenous deposits are slowly carried towards, over or underneath the emerged land. The rocks subsequently re-formed beneath continental areas out of these terrigenous materials, under great pressure and in hydrothermal conditions, would be more acid than the rocks from which they were originally derived, and it is well ‘known that the acid silicates have a lower specific gravity than the intermediate or basic ones. By a continual repetition of this process the continental protuberances have been gradually built up of lighter materials than the other parts of the litho- sphere. The relatively light quartz, which is also the most refractory, the most stable and the least fusible among rock- forming minerals, plays in all this the principal vé/e. The average height of the surface of the continents is about three miles above the average level of the abysmal regions. If now we assume the average density of the crust beneath the continents to be 2°5, and of the part beneath the abysmal regions to be 3, then the spheroidal surface of equal pressure—the tektosphere—would have a minimum depth of eighteen miles beneath the continents and fifteen miles beneath the oceans, or if we assume the density of the crust beneath the continents to ‘be 2°5, and beneath the abysmal regions to be 2°8, then the tektosphere would be twenty-eight miles beneath the continents and twenty-five miles beneath the oceans. The present condition of the earth’s crust might be brought about by the disintegration of a quantity of quartz-free volcanic rock, covering the continental areas to a depth of eighteen miles, and the re-formation of rocks out of the disintegrated materials. Where the lighter and more bulky substances have accumulated there has been a relative increase of volume, and in consequence bulging has taken place at the surface over the continental areas. Where the denser materials have been laid down there has been flattening, and in consequence a depres- sion of the abysmal regions of the ocean-basins. It is known that, as a general rule, where large masses .of sediment have been deposited, their deposition has been accompanied by a depression of the area. On the other hand, where broad mountain platforms have been subjected to extensive erosion, the loss of altitude by denudation has been made good by a rise of the platform. This points to a movement of matter. on to the continental areas. If this be anything like a true’ conception of the interactions that are taking place between the various geospheres of which our globe is made up, then we can understand why, in the gradual evolution of the surface features, the average level of the continental plains now stands permanently about three miles above the average level of those plains which form the floor of the deep ocean-basins. We may also understand how the defect of mass under continents and an excess. of mass under the oceans have been brought about, as well as deficiency of mass under mountains and excess of mass under plains. Even the local anomalies indicated by the plumb-line, gravity and magnetic observations may in this way receive a rational explanation. It has been urged that an enormous time—greater even than what is demanded by Darwin—would be necessary for NO. 1561, VOL. 60] NATURE [SEPTEMBER 28, 1899 an evolution of the existing surface features on these lines. I do not think so. Indeed, in all that relates to geological time I agree, generally speaking, with the physicists rather than with the biologists and geologists. Progress of Oceanic Research. Ihave now touched on some of the problems and speculations suggested by recent deep-sea explorations ; and there are many others, equally attractive, to which no reference has been made. It is abundantly evident that, for the satisfactory explanation of many marine phenomena, further observations and explorations are necessary. Happily there is no sign that the interest in oceanographical work has in any way slackened. On the con- trary, the number of scientific men and ships engaged in the study of the ocean is rapidly increasing. Among all civilised peoples and in all quarters of the globe the economic importance of many of the problems that await solution is clearly recognised. We have every reason to be proud of the work continually carried on by the officers and ships attached to the Hydro- graphic Department of the British Navy. They have surveyed coasts in all parts of the world for the purposes of navigation, and within the past few years have greatly enlarged our know- ledge of the sea-bed and deeper waters over wide stretches of the Pacific and other oceans. The samples of the bottom which are procured, being always carefully preserved by the officers, have enabled very definite notions to be formed as to the geographical and bathymetrical distribution of marine deposits. The sh ps belonging to the various British telegraph cable companies have done most excellent work in this as well as in other directions. Even during the present year Mr. R. E. Peake has in the s.s. Srz¢annza procured 477 deep soundings in the North Atlantic, besides a large collection of deep-sea deposits, and many deep-sea temperature and current observations. The French have been extending the valuable work of the Talisman and Travailleur, while the Prince of Monaco is at the present moment carrying on his oceanic investigations in the Arctic Seas with a large newJyacht elaborately and specially fitted out for such work. The Russians have recently been engaged in the scientific exploration of the Black Sea and the Caspian Sea, and a special ship is now employed in the investigation of the Arctic fisheries of the Murman coast under the direction of Prof. Knipowitsch. Admiral Makaroff has this summer been hammering his way through Arctic ice, and at the same time carrying on a great variety of systematic observations and experiments on board the Yerrak—the most powerful and most effective instrument of marine research ever constructed. Mr, Alexander Agassiz has this year recommenced his deep-sea explorations in the Pacific on board the U.S. steamer A/batross. He proposes to cross the Pacific in several directions, and to conduct investigations among the Paumotu and other coral island groups. Prof. Weber is similarly employed on board a Dutch man-of-war in the East Indian Seas. The Deutsche Seewarte at Hamburg, under the direction of Dr. Neumayer, continues its praiseworthy assistance and encouragement to all investigators of the ocean, and this year the important German Deep-Sea Expedition, in the s.s. Va/divéa, arrived home after most successful oceanographical explorations in the Atlantic, Indian and Great Southern Oceans. The Be/gica has returned to Europe safely with a wealth of geological and biological collections and physical observations, after spending, for the first time on record, a whole winter among the icefields and icebergs of the Antarctic. Mr. Borchgrevink in December last again penetrated to Cape Adare, successfully landed his party at that point and is now winter- ing on the Antarctic continent. The expeditions of Lieut. Peary, of Prof. Nathorst, of Captain Sverdrup, and of the Duke of Abruzzi, which are now in progress, may be expected to yield much new information about the condition of the Arctic Ocean. Mr. Wellman has just returned from the north of Franz Josef Land with observations of considerable interest. — Some of the scientific results obtained by the expeditions in the Danish steamer golf have lately been published, and these, along with the results of the joint work pursued for many years by the Swedes, Danes and Norwegians, may ultimately have great economic value from their direct bearing on. fishery problems and on weather forecasting over long periods of time. SEPTEMBER 28, 1899] NATURE 527 Largely through the influence of Prof.’ Otto Pettersson, an International Conference assembled at Stockholm a few months ago, for the purpose of deliberating as to a programme of con- joint scientific work in the North Sea and northern parts of the Atlantic, with special reference to the economic aspect of sea- fisheries. A programme was successfully drawn up, and an organisation suggested for carrying it into effect; these proposals are now under the consideration of the several States. The Norwegian Government has voted a large sum of money for building a special vessel to conduct marine investigations of the nature recommended by this conference. It is to be hoped the other North Sea Powers may soon follow this excellent example. The various marine stations and laboratories for scientific research in all parts of the world furnish each year much new knowledge concerning the ocean. Among our own people the excellent work carried on by the Marine Biological Association, the Irish Fisheries Department, the Scottish Fishery Board, the Lancashire Fisheries Committee, the Cape and Canadian Fisheries Departments, is well worthy of recognition and con- tinued support. Mr. George Murray, Mr. H. N. Dickson, Prof. Cleve, Prof. Otto Pettersson, Mr, Robert Irvine and others have, with the assistance of the officers of the Mercantile Marine, accumulated in recent years a vast amount of inform- ation regarding the distribution of temperature and salinity, as well as of ‘the planktonic organisms at the surface of the ocean. The papers by Mr. H. C. Russell on the icebergs and currents of the Great Southern Ocean, and of Mr. F. W. Walker on the density of the water in the Southern Hemisphere, show that the Australian Colonies are taking a practical interest in oceanographical problems. Proposed Antarctec Explorations. The great event of the year, from a geographical point of view, is the progress that has been made towards the realisation of a scheme for the thorough scientific exploration in the near future of the whole South Polar region. The British and German Governments have voted or guaranteed large sums of money to assist in promoting this object, and princely donations have likewise been received from private individuals, in this connection the action of Mr. L. W. Longstaff in making a gift of 25,000/., and of Mr. A. C. Harmsworth in promising 5000/., being beyond all praise. There is an earnest desire among the scientific men of Britain and Germany that there should be some sort of co-operation with regard to the scientific work of the two expeditions, and that these should both sail in 19c1, so that the invaluable gain attaching to simultaneous observations may be secured, Beyond this nothing has, as yet, been definitely settled. The members of the Association will presently have an opportunity of express- ing their opinions as to what should be attempted by the British expedition, how the work in connection with it should be arranged, and how the various researches in view can best be carried to a successful issue. I have long taken a deep interest in Antarctic exploration, because such exploration must necessarily deal largely with oceanographical. problems, and also because I have had the privilege of studying the conditions of the ocean within both the Arctic and Antarctic circles. In the year 1886 I published an article on the subject of Antarctic Exploration in the Sco/tish Geographical Magazine. . This article led to an interesting interview, especially when viewed in the light of after events, for, a few weeks after it appeared in type, a young Norwegian walked into the Chal/enger office in Edinburgh to ask when the proposed expedition would probably start, and if there were any chance of his services being accepted. His name was Nansen. When at the request of the President I addressed the Royal Geographical Society on the same subject in the year 1893, I made the following statement as to what it seemed to me should be the general character of the proposed exploration: ‘‘A dash at the South Pole is not, however, what I advocate, nor do I believe ¢hat is what British science at the present time desires. It demands rather a steady, continuous, laborious and systematic exploration of the whole southern region with all the appliances of the modern investigator.”’ At the same time I urged further, that these explorations should be undertaken by the Royal Navy in two ships, and that the work should extend over two winters and three summers. This scheme must now be abandoned, so far at least as the NO. 1561, VOL. 60] Royal, Navy is concerned, for the Government has intimated that it can spare neither ships nor officers, men nor money, for an undertaking of such magnitude. The example of Foreign Powers—rather than the representations from our own scientific men—appears to have been chiefly instrumental in at last inducing the Government to promise a sum of 45,000/., pro- vided that an equal amount be forthcoming from other sources. This resolve throws the responsibility for the financial adminis- tration, for the equipment and for the management of this. exploration on the representative scientific societies, which have no organisation ready for carrying out important executive work on such an extensive scale. iam doubtful whether this state of matters should be regarded as a sign of increasing lukewarm- ness on the part of the Government towards marine research, or should rather be looked on as a most unexpected and welcome recognition of the growing importance of science and scientific men to the affairs of the nation. Let us adopt the latter view, and accept the heavy responsibility attached thereto. f Any one who will take the trouble to read, in the Proceedings of the Royal Society of London, the account of the discussion which recently took place on ‘‘ The Scientific Advantages of an Antarctic Expedition,” will gather some idea of the number and wide range of the subjects which it is urged should be investi- gated within the Antarctic area; the proposed researches have to do with almost every branch of science. Unless an earnest attempt be made to approach yery near to the ideal there sketched out, widespread and ‘lasting disappointment will certainly be felt among the scientific men of this country. ~The proposed. expedition should not be one of adventure. Not a rapid invasion and a sudden retreat, with tales of hardships and risks, but a scientific occupation of the unknown area by observation and experiment should be aimed at in these days. I haye all along estimated the cost of a well-equipped Antarctic expedition at about 150,000/. I see no reason for changing my views on this point at the present time, nor on the general scope of the work to be undertaken by the proposed expedition, as set forth in the papers I have published on the subject. There is now a sum of at most 90,000/. in hand, or in view. If one ship should be specially built for penetrating the icy region, and be sent south with one naturalist on board, then such an expedition may, it will be granted, bring back interest- ing and important results. But it must be distinctly understood that this is not the kind of exploration scientific men have been urging on the British public for the past fifteen or twenty years. We must, if possible, have two ships, with landing parties for stations on shore, and with a recognised scientific leader and staff on board of each ship. Although we cannot have the Royal Navy, these ships can be most efficiently officered and manned from the Mercantile Marine. With only one ship: many of the proposed observations would have to be cut out of the programme. In anticipation of this being the case, there are at the present moment irreconcilable differences of opinion among those most interested in these explorations, as to which sciences must be sacrificed, The difficulties which at present surround this undertaking are fundamentally those of money. These difficulties would at once disappear, and others would certainly be overcome, should the members of the British Association at this meeting agree to place in the hands of their President a sum of 50,000/., so that the total amount available for Antarctic exploration would become. something like 150,000/, Although there is but one central Government, surely there are within the bounds of this great Empire two more men like Mr. Longstaff. The Govern- ment has suddenly placed the burden of upholding the high traditions of Great Britain in marine research and exploration on the shoulders of her scientific men. In their name I appeat to all our well-to-do fellow-countrymen in every walk of life for assistance, so that these new duties may be discharged in a manner worthy of the Empire and of the well-earned reputation, of British Science. SECTION G. MECHANICAL SCIENCE. OPENING ADDRESS BY SIR WILLIAM WuiTtE, K.C.B., LL.D., F.R.S., PRESIDENT OF THE SECTION. IN this Address it is proposed to review briefly the character- istic features of the progress made in steam navigation; to. glance at the principal causes of advance in the speeds of steam- ships and in the lengths of the voyages on which such vessels 528 NATURE [SEPTEMBER 28, 1899 can’ be successfully employed ; and to indicate how the experience and-achievement of the last sixty years bear upon the prospects of further advance. There is reason to hope that this choice of subject is not inappropriate. From the beginning of steam navigation the British Association in its corporate capacity, by the appointment of special committees, and by the action of individual members; has greatly assisted the scientific treatment of steamship design. Valuable contributions bearing on the resistance offered by water to the motion of ships, the conduct and analysis of the results of steamship trials, the efficiency of propellers and cognate subjects have been published in the Reports of the Association. Many of these have largely influenced practice, and most of them may be claimed as the work of this Section. On this occasion no attempt will be made either to summarise or appraise the work that has been done. It must suffice to mention the names of three men to whom naval architects are deeply indebted, and whose labours are ended—Scott Russell, Rankine, and William Froude. Each of them did good work, but to Froude we owe the device and application of the method of model experiment with ships and propellers, by means of which the design of vessels of novel types and unprecedented speeds can now be undertaken with greater confidence than heretofore. As speeds increase, each succeeding step in the ascending scale becomes more difficult, and the rate of increase in the power to be developed rapidly augments. Looking back on what has been achieved, it is impossible to overrate the courage and skill displayed by the pioneers of steam navigation, who had at first to face the unknown, and always to depend almost entirely on experience gained with actual ships, when they undertook the production of swifter vessels. Their successors of the present day have equal need to make a thorough study of the performances of steamships both in smooth water and at sea. In many ways they have to face greater difficulties than their predecessors, as ships increase in size and speed. On the other hand, they have the accumulated experience of sixty years to draw upon, the benefit of improved methods of trials of. steam- ships, the advantage of scientific procedure in the record and analysis of such trials and the assistance of model experiments. Steamship design to be successful must always be based on experiment and experience as well as on scientific principles and processes. It involves problems of endless variety and great complexity. The services to be performed by steamships differ in character, and demand the production of many distinct types of ships and propelling apparatus. In all these types, however, there is one common requirement—the attainment of a specified speed. And in all types there has been a continuous demand for higher speed. Stated broadly, the task set before the naval architect in the design of any steamship is to fulfil certain conditions of speed in a ship which shall not merely carry fuel sufficient to traverse a specified distance at that speed, but which shall carry a specified load on a limited draught of water. Speed, load, power and fuel supply are all related ; the two last have to be determined in each case. In some instances other limiting conditions are imposed affecting length, breadth or depth. In all cases there are three separate efficiencies to be considered: those of the ship as influenced by her form; of the propelling apparatus, including the generation of. steam in the boilers and its utilisa- tion in the engines ; and of the propellers. Besides these con- siderations, the designer has to take account of the materials and structural arrangements which will best secure the association of lightness with strength in the hull of the vessel. He must select «hose types of engines and boilers best adapted for the service proposed. Here the choice must be influenced by the length of the voyage, as well as the exposure it may involve to storm and stress. Obviously the conditions to be fulfilled in an ocean- going passenger steamer of the highest speed, and in a cross- Channel steamer designed to make short runs at high speed in comparatively sheltered waters, must be radically different. And so must be the conditions ina swilt sea-going cruiser of large size and great coal endurance, from those best adapted for a torpedo boat or destroyer. There is, in fact, no general rule applicable to all classes of steamships : each must be considered and dealt with independently, in the light of the latest experience and improvements. For merchant ships there is always the com- mercial consideration—Will it pay ? For warships there is the corresponding inquiry—Will the cost be justified by the fighting power and efficiency ? NO. 1561, VOL. 60] Charactiristics of Progress in Steam Navigation. Looking at the results so far attained, it may be said that progress in steam navigation has been marked by the following characteristics :— (1) Growth in dimensions and weights of ships, and large increase in engine-power, as speeds have been raised. (2) Improvements in marine engineering accompanying increase of steam pressure, Economy of fuel and reduction in the weight of propelling apparatus in proportion to the power developed. (3) Improvements in the materials used in shipbuilding ; better structural arrangements; relatively lighter hulls and larger carrying power. (4) Improvements in form, leading to diminished resistance and economy of power expended in propulsion. These general statements represent well-known facts—so familiar, indeed, that their full significance is often overlooked. It would be easy to multiply illustrations, but only a few repre- sentative cases will be taken. Transatlantic Passenger Steamers. The Transatlantic service naturally comes first. It is a simple case, in that the distance to be covered has remained practically the same, and that for most of the swift passenger steamers cargo-carrying capacity is not a very important factor in the design. In 1840 the Cunard steamship Arz/annza, built of wood, propelled by paddle-wheels, maintained a sea-speed of about 84 knots. Her steam pressure was 12 lbs. per square inch. She was 207 feet long, about 2000 tons in displacement, her engines developed about 750 horse-power, and her coal con- sumption was about 40 tons’ per day, nearly 5 Ibs. of coal per indicated horse-power per hour. She had a full spread of sail. In 1871 the White Star steamship Oceanzc (first of that name) occupied a leading position. She was iron-built, propelled by a screw, and maintained a sea-speed of about 144 knots. The steam pressure was 65 lbs. per square inch, and the engines were on the compound principle. She was 420 feet long, about 7200 tons in displacement, her engines developed 3000 horse-power, and she burnt about 65 tons of coal per day, or about 2 lbs. per indicated horse-power per hour. She carried a considerable spread of sail. In 1889 the White Star steamer Zex/onzc appeared, propelled by twin screws and practically with no sail-power. She is steel- built, and maintains a sea-speed of about 20 knots. The steam pressure is 180 lbs. per square inch, and the engines are on the triple expansion principle. She is about 565 feet long, 16,000 tons displacement, 17,000 horse-power indicated, with a coal consumption of about 300 tonsa day, or from 1°6 to 1°7 Ibs. per indicated horse-power per hour. In 1894 the Cunard steamship Campania began her service, with triple expansion engines, twin screws and no sail-power. She is about 600 feet long, 20,000 tons displacement, develops about 28,000 horse-power at full speed of 22 knots, and burns about 500 tons of coal per day. The new Oceanzc, of the White Star Line, is just beginning her work. She is of still larger dimensions, being 685 feet in length and over 25,000 tons displacement. From the authori- tative statements made, it appears that she is not intended to exceed 22 knots in speed, and that the increase in size is to be largely utilised in additional carrying power. The latest German steamers for the Transatlantic service are also notable. A speed of 224 knots has been maintained by the Kazsex Wilhelm der Grosse, which is 25 feet longer than the Campania. Two still larger steamers are now building. The Deutschland is 660 feet long and 23,000 tons displacement ; her engines are to be of 33,000 horse-power, and it is estimated she will average 23 knots. The other vessel is said to be 700 feet long, and her engines are to develop 36,000 horse-power, giving an estimated speed of 234 knots. All these vessels have steel hulls and twin screws. It will be noted that to gain about three knots an hour nearly 50 per cent. will have been added to the displacement of the Zez/onzc, the engine-power and coal consumption, will be doubled, and the cost increased proportionately. Sixty years of continuous effort and strenuous competition on this great ‘‘ ocean ferry” may be summarised in the following statement. Speed has been increased from 84 to 224 knots ; the time on the voyage has heen reduced to about 38 per cent. SEPTEMBER 28, 1899] NATURE 529 of what it was in 1840. Ships have been more than trebled in length, about doubled in breadth, and increased tenfold in dis- placement, The number of pissengers carried by a steamship has been increased from about 100 to nearly 2000. The engine-power has been made forty times as great. , The ratio of horse-power to the weight driven has been increased fourfold. The rate of coal consumption (measured per horse-power per hour) is now only about one-third what it was in 1840. To drive 2000 tons weight across the Atlantic at a speed of 84 knots, about 550 tons of coal were then burnt : now, to drive 20,000 tons. across at 22 knots, about 3000 tons of coal are burnt. With the low pressure of steam and heavy slow-moving paddle-engines of 1840, each ton weight of machinery, boilers, &c., produced only about 2 horse-power for continuous working at sea. With modern twin-screw engines and high steam pressure, each ton weight of propelling apparatus produces from 6 to 7 horse- power. Had the old rate of coal consumption continued, instead of 3000 tons of coal, go0o tons would have been required fora voyage at 22 knots. Had the engines been proportionately as heavy as those in use sixty years ago, they would have weighed about 14,000 tons. In other words, machinery, boilers, and coals would have exceeded in weight the total weight of the Campania as she floats to-day. There could not be a more striking illustration than this of the close relation between im- provements in marine engineering and the development of steam navigation at high speeds. Equally true is it that this development could not have been accomplished but for the use of improved materials and Structural arrangements. Wood, as the principal material for the hulls of high-powered swift steamers, imposed limits upon dimensions, proportions and powers which would have been a bar to progress. The use of iron, and later of steel, removed those limits. The percentage of the total displacement devoted to hull in a modern Atlantic liner of the largest size is not much greater than was the corresponding percentage in the wood- built 4rz/annia of 1840, of one-third the length and one-tenth the total weight. Nor must it be overlooked that with increase in dimensions have come considerable improvements in form, favouring economy in propulsion. This is distinct from the economy tesulting from increase in séze, which Brunel appreciated thoroughly half a century ago when he designed the Great Sritotx and. the Great Eastern. The importance of a due celation’ between the lengths of the ‘‘entrance and run” of steamships and their intended maximum speeds, and the advantages of greater length and fineness of form as speeds are increased, were strongly insisted upon by Scott Russell and Froude. Naval architects, as a matter of course, now act upon the principle, so far as other conditions permit. For it must never be forgotten that economy of propulsion is only one of many desiderata which must be kept in view in steamship design. Structural weight and strength, seaworthiness and stability, all claim attention, and may necessitate modifications tn dimensions and form which do not favour the maximum economy of propulsion. Swift Passenger Steamers for Long Voyages. Changes similar to those described for the Transatlantic service have been in progress on all the great lines of ocean traffic. In many instances increase in size has been due, not only to increase in speed, but to enlarged carrying power and the extension of the lengths of voyages. No distance is now found too great for the successful working of steamships, and the sailing Heet is rapidly diminishing in importance. So far as long-distance steaming is concerned, the most potent factor has undoubtedly been the marvellous economy of fuel that has resulted from higher steam pressures and greater expansion. In all cases, however, advances have been made possible, not merely by economy of fuel, but by improvements in form, structure and propelling apparatus, and by increased dimen sions. Did time permit, this might be illustrated by many interesting facts drawn from the records of the great steamship companies which perform the services to the Far East, Australia, South America, and the Pacific. As this is not possible, I must: be content with a brief statement regarding the development of the fleet of the Peninsular and Oriental Company. _ The paddle steamer William Fawcett of 1829 was about 75 feet long, 200 tons displacement, of 60 nominal horse-power {probably about 120 indicated. horse-power), and in favourable NO. 1561, VOL. 60] weather steamed at a speed of 8 knots. Her hul was of wood, and, like all the steamers of that date, she had considerable sail-power. In 1853 the Azmalaya iron-built screw steamer of this line was described as ‘‘ of larger dimensions than any then afloat, and of extraordinary speed.” She was about 340 feet long, over 4000 tons load displacement, 2000 indicated horse-power on trial, with an average sea-speed of about 12 knots. The steam pressure was 14 lbs. per square inch, and the daily coal con- sumption about 70 tons. This vessel was transferred to the Royal Navy and did good service as a troopship for forty years. In 1893 another Hza/aya was added to the company’s fleet: She was steel-built, nearly 470 feet long and 12,000 tons load displacement, with over 8000 indicated horse-power and a capability to sustain 17 to 18 knots at sea, ona daily consump- tion of about 140 tons of coal. The steam pressure is 160 lhs. per square inch, and the engines are of the triple expansion type. Comparing the two Azmaya/as, it will be seen that in forty years the length has been increased about qo per cent., dis- placement trebled, horse-power quadrupled and speed increased about 50 per cent. The proportion of horse-power to displace- ment has only been increased as three to four, enlarged dimensions having secured relative economy in propulsion. The rate of coal consumption has been probably reduced to about one-third of that in the earlier ship The latest steamers of the line are of still larger dimensions, being 500 feet long and of proportionately greater displace- ment. [It is stated that the Azma/aya of 1853 cost 132,000/. complete for sea; the corresponding outlay on her successors is not published, but it is probably twice as great. On the service to the Cape similar developments have taken place. Forty years ago vessels less than 200 feet long and about 7 knots performed the service, whereas the latest additions to the fleets exceed 500 feet in length, and can, if required, be driven at 17 to 18 knots, ranking in size and power next’ to the great Transantlantic liners. ) Commercial considerations necessarily regulate what is under- taken in the construction of merchant steamers, including the swilt vessels employed in the conveyance of passengers and mails. The investment of 600,000/. to 700,000/. in a single vessel like a great Transatlantic liner is obviously a serious matter for private owners; and even the investment of half that amount in a steamer of less dimensions and speed is not to be lightly undertaken. It is a significant fact that, whereas fifteen years ago nearly all the largest and swiftest ocean steamers were British built and owned, at the present time there is serious competition in this class by German, American and French companies. It is alleged that this change has resulted from the relatively large subsidies paid by foreign Governments to the owners of swift steamers ; and that British owners, being handicapped in this way, cannot continue the competition in size and speed on equal terms unless similarly assisted. This is not the place to enter into any discussion of such matters, but they obviously involve greater considerations than the profit of shipowners, and have a bearing onthe naval defence of the Empire. In 1887 the Government recognised this fact, and made arrangements for the subventiun and armament of a number of the best mercantile steamships’ for use as auxiliary cruisers. Since then other nations have adopted the policy, and given such encouragement to their shipowners that the numbers of swift steamers suitable for employnient as’ cruisers have been largely increased. Not long since’the First Lord of the Admiralty announced to Parliament that the whéle’ subject was again under consideration. : Cargo and Passenger Steamers. ~ ' Cargo steamers, no less than passenger steamers, have been affected by, the improvements mentioned. Remarkable developments have occurred recently, not merely inthe purely cargo-carrier, but in the construction of vessels of large size’ and good speed carrying very great weights of cargo and considerable numbers of passengers. The much-decried “‘ocean-tramp” of the present day exceeds in speed the passenger and mail steamer of fifty years ago. Within ten years vessels in which cargo-carrying is the chief element of commercial success have been increased in length from 300 or 400 feet to 500 or 600 feet ; in gross register tonnage from 5000 to over 13,000 tons ; and in speed from 10 or 12 knots'to 15 or 16 knots. Vessels are now building for the Atlantic service which can carry 12,000 to 13,000 tons deadweight, in addition 530 NARGRE [SEPTEMBER 28, 1899 to passengers, while possessing a sea-speed as high as that of the swiftest mail steamers afloat in 1880. Other vessels of large carrying power and good speed are running on much longer voyages, such as to the Cape and Australia. In order to work these ships successfully very complete organisation is necessary for the collection, embarkation and discharge of cargo. The enterprise and skill of shipowners have proved equal to this new departure, as they have in all other developments of steamships. F How much further progress will be made in the sizes and speeds of these mixed cargo and passenger steamers cannot be foreseen. The limits will be fixed by commercial considerations, and not by the capability of the shipbuilder. In passing, it may be noted that while the lengths and breadths of steamships have been greatly increased, there has been but a moderate increase in draught. Draught of water is, of course, practically determined by the depths available in the ports and docks frequented, or in the Suez Canal for vessels trading to the East. From the naval architect’s point of view, increase in draught is most desirable as favouring increase of carrying power and economy of propulsion. This fact has been strongly represented by shipowners and ship-designers, and not without result. The responsible authorities of many of the principal ports and of the Suez Canal have taken action towards giving greater depth. é Other changes have become necessary on the part of dock and port authorities in consequence of the progress made in shipbuilding. Docks and dock-entrances have had to be increased in size, more powerful lifting appliances provided and large expenditure incurred. There is no escape from these changes if the trade of a port is to be maintained. The chief lesson to be learnt from past experience is that when works of this character are planned it is wise to provide a large margin beyond the requirements of existing ships. Cross-Channel Steamers. The conditions to be fulfilled in vessels designed to steam at high speed for limited periods differ essentially from those holding good in ocean-going steamers. None the less interest attaches, however, to cross-Channel steamers, and in no class has more notable progress been made. It is much to be desired that at this meeting some competent authority should have presented to the Association an epitome of the history of the steam packet service between Dover and the continent. I can- not attempt it. So far as I am informed, the first steamer was placed on this route in 1821, was of 90 tons burden, 30 horse- power nominal, and maintained a speed of 7 to 8 knots. She was built by Denny of Dumbarton, engined by David Napier and named the od Roy. It is interesting to note that the lineal successors of the builder of this pioneer vessel have produced some of the most recent and swiftest additions to the cross-Channel service. In 1861-2 a notable advance was made by the building of vessels which were then remarkable for structure and speed, although small and slow when compared with vessels now running. Their designers realised that lightness of hull was of supreme importance, and with great trouble and expense obtained steel of suitable quality. The machinery was of special design and relatively light for the power developed. A small weight of coal and cargo had to be carried, and the draught of water was kept to about 7 feet. Under then existing conditions it was a veritable triumph to attain speeds of 15 to 16 knots in vessels only 190 feet long, less than 25 feet broad, and under 350 tons in displacement. To raise the trial speed to 20 or 21 knots in later vessels performing the same service, whose design includes the improvements of a quarter of a century, it has been found necessary to adopt lengths exceeding 320 feet and breadths of about 35 feet, with engines developing 4500 to 6000 indicated horse-power, and with very great increase in coal consumption and cost. On other cross- Channel services between Dover and the continent still larger and more powerful paddle-steamers are employed. Another interesting contrast is to be found in the comparison of the steamers running between Holyhead and Kingstown in 1860 and at the present time. The Lezzster of 1860 was 328 feet long, 35 feet broad and rather less than 13 feet draught. Her trial displacement was under 2000 tons and with 4750 horse-power she made 17$ knots. She had a steam pressure of 25 lbs. per square inch and was propelled by paddle-wheels driven by slow-moving engines of long stroke. . Her successor NO. 1561, VOL. 60] of 1896 is about 30 feet greater length, 64 feet greater breadth and about 10 per cent. greater displacement. The steam pressure is 170 lbs. per square inch. Forced draught is used in the stokeholds. Twin screws are adopted, driven by quick- running vertical engines of the triple expansion type. Very great economy of coal consumption is thus secured as compared with the earlier vessel, and much lighter propelling apparatus in proportion to the power, which is from 8000 to 9000 horse- power at the full speed of 23 knots. The hull is built of steel, and is proportionately lighter. This is a typical case, and illustrates the effect of improve- ‘aents in shipbuilding and engineering in thirty-five years. The 'uter ship probably requires to carry no greater load of coal than, if so great as, her predecessor, although her engine-power is nearly double. The weight devoted to propelling machinery and boilers is probably hot so great. Thanks to the use of steel instead of iron, and to improved structural arrangements, the weight of hull is reduced in comparison with dimensions, and a longer ship is produced better adapted to the higher speed. Messrs. Laird of Birkenhead, who built three of the Lezzster class forty years ago, and have built all the new vessels, are to be congratulated on their complete success. Between such vessels designed for shert runs at high speed and requiring therefore to carry little coal, while the load carried exclusive of coal is trifling, and an ocean-going steamer of the same average speed designed to make passages of 3000 miles, there can obviously be little in common. But equal technical skill is required to secure the efficient performance of both services. In the cross-Channel vessel, running from port to port, and under constant observation, conditions of working in engine and boiler rooms, as well as relative lightness in scant- lings of hull, can be accepted which would be impossible of application in a sea-going ship. These circumstances in association with the small load carried explain the apparent gain in speed of the smaller vessel in relation to her dimensions. Increase in Size and Speea of Warships. Turning from sea-going ships of the mercantile marine to war- ships, one finds equally notable facts in regard to increase in speed, associated with enlargement in dimensions and advance in propelling apparatus, materials of construction, structura} arrangements and form. Up to 1860 a measured-mile speed of 12 to 13 knots was considered sufficient for battleships and the largest classes of cruisers. All these vessels possessed good sail-power and used it freely as an auxiliary to steam, or as an alternative when cruising or making passages. When armoured battleships were built (1859) the speeds on measured-mile trials were raised to 14 or 144 knots, and so re- mained for about twenty years. Since 1880 the speeds of battle- ships have been gradually increased, and in the latest types the measured-mile speed required is 19 knots. Up to 1870 the corresponding speeds in cruisers ranged from 15 to 16 knots. Ten years later the maximum speeds were 18 to 183 knots in a few vessels. Since then trial speeds of 20 to 23 knots have been attained or are contemplated. There is, of course, a radical distinction between these measured-mile performances of warships and the average sea- speeds of merchant steamers above described. But for purposes of comparison between warships of different dates, measured mile trials may fairly be taken as the standard. For long-distance steaming the power developed would necessarily be much below that obtained for short periods and with everything at its best. This is frankly recognised by all who are conversant with the warship design, and fully allowed for in estimates of sea-speeds. On the other hand, it is possible to point to sea trials made with recent types where relatively high speeds have been maintained for long periods. For example, the battleship Xoyal Soverezgr has maintained an average speed of 15 knots from Plymouth to Gibraltar, and the ezown has maintained an equal speed from Bermuda to Spithead. As instances of good steaming by cruisers, reference may be made to 60-hour trials with the Terrible when she averaged over 20 knots, and to the run home from Gibraltar to the Nore by the Dzaden: when she exceeded 19 knots. Vessels of the Pelorws class of only 2100 tons dis- placement have made long runs at sea averaging over 17 knots. Results such as these represent a substantial advance in speed of Her Majesty’s ships in recent years. Similar progress has been made in foreign warships built abroad as well as in this country. It is not proposed to give SEPTEMBER 28, 1899 | WA TU Ris 53! any facts for these vessels, or to compare them with results obtained by similar classes of ships in the Royal Navy. Apart from full knowledge of the conditions under which speed trials are made, a mere statement of speeds attained is of no service. One requires to be informed accurately respecting the duration of the trial, the manner in which engines and boilers are worked, the extent to which boilers are “*forced,” or the proportion of heating surface to power in- dicated, the care taken to eliminate the influence of tide or current, the mode in which the observations of speed are made, and other details, before any fair or exact comparison is possible between ships. For present purposes, therefore, it is preferable to confine the illustrations of increase in speed in warships to results obtained under Admiralty conditions, and which are fairly comparable. A great increase in size has accompanied this increase in speed, but it has resulted from other changes in modern types, as well as from the rise in speed. Modern battleships are of 13,000 to 15,000 tons, and modern cruisers of 10,000 to 14,000 tons, not merely because they are faster than their predecessors, but because they have greater powers of offence and defence and possess greater coal endurance. Only a detailed analysis, which cannot now be attempted, could show what is the actual influence of these several changes upon size and cost, and how greatly the improvements made in marine engineering and ship- building have tended to keep down the growth in dimensions consequent on increase in load carried, speed attained, and distance traversed. It will be noted also that, large as are the dimensions of many classes of modern warships, they are all smaller in length and displacement than the largest mercantile steamers above de- scribed. There is no doubt a popular belief that the contrary is true, and that warships exceed merchant ships in tonnage. This arises from the fact that merchant ships are ordinarily described, not by their displacement tonnage, but by their ‘‘ registered tonnage,” which is far less than their displacement. As a matter of fact, the largest battleships are only of about two-thirds the displacement of the largest passenger steamers, and from 200 to 300 feet shorter. The largest cruisers are from 100 to 200 feet shorter than the largest passenger steamers, and abeut 60 per cent. of their displacement. In breadth. the warships exceed the largest merchant steamers by 5 to 10 feet. This difference in form and proportions is the result of radical differences in the vertical distribution of weights carried, and is essential to the proper stability of the warships. Here we find an illustration of the general principle underlying all ship-designing. In selecting the forms and proportions of a new ship, consider- ations of economical propulsion cannot stand alone. They must be associated with other considerations, such as stability, protection and manceuvring power, and in the final result economy of propulsion may have to be sacrificed, to some extent, in order to secure other essential qualities. Advantages of Increased Dimensions. Before passing on, it may be interesting to illustrate the gain in economy of propulsion resulting from increase in dimensions by means of the following table, which gives particulars of a number of typical cruisers, all of comparatively recent design :— No.2 | No.3 | No.4 | No.5 | ie = Length (feet) a PA 280) 300 | 360 | 435 | 500 Breadth (feet) cer pale #35| Mas | 60 69 71 Mean draught (feet) w=] 33|) TOR Meget = 2a 26} Displacement (tons) |II,000 14,200 Indicated horse-power for } 20 knots... : ... 6000) 9000 |II,000 |14,000 15,500 Indicated horse-power per | ton of displacement ...| 3°33] 2°65 | 1°48 | 1°27 1°09 The figures given are the results of actual trials, and embody therefore the efficiencies of propelling machinery, propellers and forms of the individual ships. Even so they are instructive. Comparing the first and last, for example, it will be seen that, while the displacement is increased nearly ezgh¢fold, the power for 20 knots is only increased about 2°6 times. If the same types of engines and boilers had been adopted in these two vessels—which was: not the case, of course—the NO. 1561, VOL. 60] weights of propelling apparatus and coal fora given distance would have been proportional to the respective powers ; that is to say, the larger vessel would have been equipped with only 2°6 times the weight carried by the smaller. On the other hand, roughly speaking, the désposable werghts, after providing for hulls and fittings in these two vessels, might be considered to be proportional to their displacements. As a matter of fact, this assumption is distinctly in favour of the smaller ship. Adopting it, the larger vessel would have about ezgh¢ times the disposable weight of the smaller ; while the demand for pro- pelling apparatus and fuel would be only 2°6 ¢zes that of the smaller vessel. There would therefore be an enormous margin of carrying power in comparison with displacement in the larger vessel. This might be devoted, and in fact was devoted, partly to the attainment of a speed considerably exceeding 20 knots (which was a maximum for the smaller vessel), partly to increased coal endurance and partly to protection and armament. Another interesting comparison may be made between vessels Nos. 4 and 5 in the preceding table, by tracing the growth in power necessary to drive the vessels at speeds ranging from 10 knots up to 22 knots. No. 4 | No. 5 i= to knots I,500-horse-power | 1,800-horse-power [250 BusOO Mas 143) | "(I MBRTOOR ES MMs es ASOO0) %5) 1755) |) | 45,0000 1 ss 16 ”? 6,000 +B] 2? | 73500 ”? a> 18 2? 9,000 ” ” 11,000 99 tA 20 ” 14,000 2” ” 15,500 > ” 22 23,000 ;, ” | 23,000 ;, » | It will be noted that up to the speed of 18 knots there is a fairly constant ratio between the powers required to drive the two ships. As the speeds are increased the larger ship gains, and at 22 knots the same power is required in both ships. The smaller vessel, as a matter of fact, was designed for a maximum speed of 204 knots, and the larger for 22 knots. Unless other qualities had been sacrificed, neither space nor weight could have been found in the smaller vessel for machinery and coals corresponding to 22 knots. The figures are interesting, how- ever, as illustrations of the principle that economy of propulsion is favoured by increase in dimensions as speeds are raised. Going a step further, it may be assumed that in unsheathed cruisers of this class about 4o per cent. of the displacement will be required for the hull and fittings, so that the balance or ‘« disposable weight”? would be about 60 per cent. ; say 6600 tons for the smaller vessel, and $500 tons for the larger, a gain of nearly 2000 tons for the latter. If the speed of 22 knots were secured in both ships, with machinery and boilers of the same type, the larger ship would therefore have about 2000 tons greater weight available for coals, armament, armour and equipment. its ; These illustrations of well-known principles have been given simply for the assistance of those not familiar with the subject, and they need not be carried further. More general treatment of the subject, based on experimental and theoretical investiga- tion, will be found in text-books of naval architecture, but would be out of place in this Address. Sweft Torpedo Vessels. Torpedo flotillas are comparatively recent additions to war fleets. The first torpedo boat was built by Mr. Thornycroft for the Norwegian Navy in 1873, and the same gentleman built the first torpedo boat for the Royal Navy in 1877. The construc: tion of the larger class, known as ‘‘torpedo-boat destroyers, dates from 1893. These various classes furnish some of the | most notable examples extant of the attainment of extraordi- | narily high speeds, for short periods and in smooth water, by vessels of small dimensions. Their qualities and performances, therefore, merit examination. 3 : 3 Mr. Thornycroft may justly be considered the pioneer in this class of work. Greatly impressed by the combination of light- ness and power embodied in railway locomotives, Mr. Thorny- croft applied similar principles to the propulsion of small boats, and obtained remarkably high speeds. His work became more widely known when the results were published of a series of trials conducted in 1872 by Sir Frederick Bramwell on a small 532 NATURE [SEPTEMBER 28, 1899 vessel named the J/zvanda. She was only 45 feet long and weighed 4 tons, yet she exceeded 16 knots on trial. The Nor- wegian torpedo boat built in 1873 was 57 feet long, 74 tons, and of 15 knots ; the first English torpedo boat of 1877 was 81 feet long, 29 tons and attained 184 knots. Mr. Yarrow also undertook the construction of small swift vessels at a very early date, and has greatly distinguished him- self throughout the development of the torpedo flotilla. Messrs. White, of Cowes, previously well known as builders of steam- boats for use on board ships, extended their operations to the construction of torpedo boats. These three firms for a consider- able time practically monopolised this special class of work in this country. Abroad they had able competitors in Normand in France, Schichau in Germany, and Herreshoff in the United States. Keen competition led to successive improvements and rapid rise in speed. During the last six years the demand for a fleet of about 100 destroyers, to be built in the shortest possible time, involved the necessity for increasing the sources of supply. At the invitation of the Admiralty, a considerable number of the leading shipbuilding and engineering firms have undertaken and successfully carried through the construction of destroyers varying from 26 to 33 knots in speed, although the work was necessarily of a novel character, involving many difficulties. As the speeds of torpedo vessels have risen, so have their dimensions increased. Within the class the law shown to hold good in larger vessels applies equally. In 1877 a first-class torpedo boat was 81 feet long, under 30 tons weight, developed 400-horse-power, and steamed 184 knots. Ten years later the corresponding class of boat was 135 feet long, 125 tons weight, developed 1500 horse-power and steamed 23 knots. In 1897 it had grown to 150 feet in length, 140 to 150 tons, 2000 horse- power and 26 knots. Destroyers are not yet of seven years’ standing, but they come under the rule. The first examples (1893) were 180 feet long, 240 tons, 4000 horse-power and 26 to 27 knots. They were followed by 30-knot vessels, 200 to 210 feet long, 280 to 300 tons, 5500 to 6000 horse-power. Vessels now in construction are to attain 32 to 33 knots, their lengths being about 230 feet, displacements 360 to 380 tons and engine-power S000 to 10,000 horse: power. Cost has gone up with size and power, and the limit of pro- gress in this direction will probably be fixed by financial con- siderations, rather than by constructive difficulties, great as these become as speeds rise. It may be interesting to summarise the distinctive features of torpedo-vessel design. (1) The propelling apparatus is excessively light in proportion to the maximum power developed. Water-tube boilers are now universally adopted, and on speed trials they are ‘‘ forced” toa considerable extent. High steam pressures are used. The engines are run at a high rate of revolution—often at 400 revolutions per minute. Great care is taken in every detail to economise weight. Speed trials at maximum power only extend over three hours. On such trials in a destroyer each ton weight of propelling apparatus produces about 45 indicated horse-power. Some idea of the relative lightness of the destroyer’s machinery and boilers will be obtained when it is stated that in a large modern cruiser with water-tube boilers, high steam pressure, and quick-running engines, the maximum power obtained on an eight hours’ trial corresponds to about 12 indicated horse-power per ton of engines, boilers, &c. That is to say, the proportion of power to weight of propelling apparatus is from three and a half to four times as great in the destroyer as it is in the cruiser. (2) A very large percentage of the total weight (or displace- ment) of a torpedo vessel is assigned to propelling apparatus. In a destroyer of 30 knots trial-speed, nearly one-half the total weight is devoted to machinery, boilers, &c. In the swiltest cruisers of large size the corresponding allocation of weight is less than 20 per cent. of the displacement, and in the largest and fastest mail steamers it is about 20 to 25 per cent. (3) The torpedo vessel carries a relatively small load of fuel, equipment, &c. Taking a 30-knot destroyer, for example, the speed trials are made with a load not exceeding 12 to 14 per cent. of the displacement. In a swift cruiser the corresponding load would be from 40 to 45 per cent., or proportionately more than three times as great. What this difference means may be illustrated by two statements. If the load in a destroyer were trebled and the vessel correspondingly increased in draught and weight, the speed attained with the same maximum power would be about three knots less. If, on the other hand, the NO. 1561, VOL. 60] vessel were designed to attain 30 knots on trial with the heavier load, her displacement would probably be increased about 70 to 80 per cent. (4) The hull and fittings of the torpedo vessel are exceedingly light in relation to the dimensions and engine-power. For many parts of the structure steel of high: tensile strength is used. Throughout, the utmost care is taken to economise weight. In small vessels, for special service, many conditions can be accepted which would be inadmissible in larger sea- going vessels. The result of all this care is the production of hull-structures having ample geveva/ strength for their special service. Lightness of scantling, of course, involves small /ocal strength against collision, grounding and other accident. Ex- perience proves, however, that this involves no serious risk or difficulty. These conditions are essential to the attainment of very high speeds for short periods. They resemble the conditions ruling the design of cross-Channel steamers, so far as relative lightness of propelling apparatus, small load and light scantlings are con- cerned. The essential differences lie in the requirements for passenger accommodation as compared with the requirements for armament of the torpedo vessel. No one has yet proposed to extend the torpedo-vessel system to sea-going ships of large dimensions. Very similar conditions for the propelling appar- atus have been accepted ina few cruisers of considerable dimen- sions, wherein high speeds for short periods were required. It is, however, unquestionable that in many ways, and particularly in regard to machinery design, the construction of torpedo vessels has greatly influenced that of larger ships. One important consideration must not be overlooked. For short-distance steaming at high speeds economy in coal con- sumption is of little practical importance, and it is all-important to secure lightness of propelling apparatus in relation to power. For long-distance steaming, on the contrary, economy in coat consumption is of primary importance ; and savings in weight of propelling apparatus, even of considerable amount, may be un- desirable if they involve increased coal consumption. Differ- ences of opinion prevail as to the real economy of fuel obtainable with boilers and engines such as are fitted in torpedo vessels. Claims aresmade for some vessels which represent remarkable economy. Only enlarged experience can settle these questions. Endurance is also an important quality in sea-going ships of large size, not merely in structures, but in propelling apparatus. The extreme lightness essential in torpedo vessels obviously does not favour endurance if high powers are frequently or con- tinuously required. Still, it cannot be denied that the results obtained in torpedo vessels show such a wide departure from those usual in sea-going ships as to suggest the possibility of some intermediate type of propelling apparatus applicable to large sea-going ships and securing sufficient durability and economy of fuel in association with further savings of weight. The Parsons Turbo-Motor. The steam turbo-motor introduced by Mr. Charles Parsons is to be described by the inventor during these meetings ; but it is impossible for me to pass it over in this review without a brief notice. This rotary engine, with its very high rate of revolution, reduces the weights of machinery, shafting and propellers greatly below the weight required in the quickest- running engines of the reciprocating type. This reduction in the proportion of weight to power carries with it, of course, the possibility of higher speed in a vessel of given dimensions ; and when large powers are employed the absolute gain is very great. An illustration of this has been given by Mr. Parsons in the 7z7dzzza. That remarkable vessel is 100 feet long and of 444 tons displacement, but she has attained 33 to 34 knots in short runs. Thereare three shafts, each carrying three screw propellers, each shaft driven by a steam turbine making over 2000 revolutions at full speed, when more than 2000-horse- power is developed. A water-tube boiler of special design supplies steam of 175 lbs. pressure, and is exceptionally light for the steam produced, being highly forced. The whole weight of machinery and boilers is 22 tons; in other words, about 100 horse-power (indicated) is produced for each ton weight of propelling apparatus. This is rather more than twice the pro- portion of power to weight as compared with the lightest machinery and boilers fitted in torpedo boats and destroyers. It will be noted that in the Zw7denza, asin the destroyers, about half the total weight is devoted to propelling apparatus ; and im both instances the load carried is relatively small. The secret SEPTEMBER 28, 1899 | WA TURE 533 of the extraordinary speed is to be found in the extreme light- ness of propelling apparatus and small load. No doubt in the 7zréénia lightness has been pushed further than it would be in vessels of larger size and greater power. In such vessels a lower rate of revolution would probably be ac- cepted, additional motors would be fitted for manceuvring and going astern, boilers of relatively greater weight would be adopted and other changes made. But, after making ample allowance for all such increases in weight, it is unquestionable that considerable economies must be possible with rotary engines. Two other vessels of the destroyer type with turbo- motors (one for the Royal Navy) are now approaching com- pletion. Their trials will be of great interest, as they will furnish a direct comparison with vessels of similar size and form, fitted with similar boilers and driven by reciprocating engines. On the side of coal consumption, Mr. Parsons claims at least equality with the best triple expansion engines. Into the other advantages attending the use of rotary engines it is not necessary now to enter, Reference must be made, however, to one matter in which Mr. Parsons has done valuable and original work. In torpedo vessels of high speed the choice of the most efficient propellers has always been a matter of difficulty, and the solution of the problem has in many instances involved extensive experimental trials. By means of alterations in propellers alone, very large increases in speed have been effected ; and even now there are difficulties to be faced. When Mr. Parsons adopted the extra- ordinary speed of revolution just named for the Zwdznza, he went far beyond all experience and precedent and had to face unknown conditions. He has found the solution, after much patient and original investigation, in the use of multiple screws of small diameter. His results in this direction are of general interest to all who have to deal with screw propulsion. Such radical changes in propelling machinery as are involved in the adoption of turbo-motors must necessarily be subjected to thorough test before they will be widely adopted. The experi- ment which the Admiralty are making is not on a small scale as regards power. Although it is made in a destroyer, about 10,000 horse-power will probably be developed and a corre- spondingly high speed attained. It may well happen that from this experiment very far-reaching effects may follow. Mr. Parsons himself has prepared many designs illustrating various applications of the system to sea-going, cross-Channel and special service vessels. Where shallowmess of draught is un- avoidable, the small diameter of the screws possible with the quick-running turbines is clearly an important matter. Comparisons between Large and Small Vessels. It has been shown that the attainment of very high speeds by vessels of small size involves many conditions not applicable to large sea-going steamships. But it is equally true that in many ways the trials of small swift vessels constitute model experiments from which interesting information may be ob- tained as to what would be involved in driving ships of large size at speeds much exceeding any of which we have experience. When the progressive steam-trials of such small vessels can be studied side by side with experiments made on models to deter- mine their resistance at various speeds, then the fullest inform- ation is obtained and the best guide to progress secured. This advantage, as has been said, we owe to William Froude. His contributions to the Reports of the British Association are classics in the literature of the resistance and propulsion of ships. In 1874 he practically exhausted the subject of frictional resistance so far as it is known ; and his Presidential Address to this Section in 1875 dealt fully and lucidly with the modern or stream-line theory of resistance. No doubt there would be advantage in extending Froude’s experiments on frictional résistance to greater lengths and to ship-shaped forms. It is probable also that dynamometric determinations of the resist- ance experienced by ships of modern forms and considerable size when towed at various speeds would be of value if they could be conducted. These extensions of what Froude accom- plished are not easily carried out; and in this country the pressure of work on shipbuilding for the Royal Navy has, for many years past, taxed to the utmost limits the capacity of the Admiralty experimental establishment so ably superintended by Mr. R. E. Froude, allowing little scope for purely scientific in- vestigations, and making it difficult to deal with the numerous experiments incidental to the designs of actual ships. Now that NO. 1561, VOL. 60] Holland, Russia, Italy and the United States have equipped experimental establishments, while Germany and France are taking steps in that direction, we may hope for extensions of purely scientific work and additions to our knowledge. In this direction, however, I am bound to say that much might be done if experimental establishments capable of dealing with questions of a general nature relating to resistance and pro- pulsion were added to the equipment of some of our universities and colleges. Engineering laboratories have been multiplied, but there is as yet no example of a model experimental tank devoted to instruction and research. It is impossible, and possibly is unnecessary, to attempt in this Address any account of Froude’s ‘‘ scale of comparison ” between ships and models at ‘‘corresponding speeds.’ But it may be of interest to give a few illustrations of the work- ing of this method, in the form of a contrast between a destroyer of 300 tons, 212 feet long, capable of steaming 30 knots an hour, and a vessel of similar form enlarged to 765 feet in length and 14,100 tons. The ratio of dimensions is here about 3°61 : 1; the ratio of displacements is 47 : 1 ; and the ratio of corresponding speeds is 1°9 : I. To 12 knots in the small vessel would correspond 22°8 knots in the large vessel ; and the resistance experienced by the large vessel at 22°8 knots (neglecting a correction for friction) should be forty-seven times that of the small vessel at 12 knots. By ex- periment, this resistance for the small vessel was found to be 18 tons. Hence, for the large vessel at 22°8 knots the resist- ance should be 84°6 tons. This would correspond to an “effective horse-power’’ of over 13,000, or to about 26,000 indicated horse-power. The frictional correction would reduce this to about 25,000 horse-power, or about 1°8 horse-power per ton. Now turning to the destroyer, it is found experimentally that at 22°8 knots she experiences a resistance of about I1 tons, corresponding to an effective horse-power of over 1700, and an indicated horse-power of about 3000: say I0 horse-power per ton, or nearly five and a half times the power per ton required in the larger vessel. This illustrates the economy of propulsion arising from increased dimensions. Applying the same process to a speed of 30 knots in the large ship, the corresponding speed in the small ship is 15 8 knots. Her resistance at that speed is experimentally determined to be 3'5 tons, and the resistance of the large ship at 30 knots (ne- glecting frictional correction) is about 165 tons. The effective horse-power of the large ship at 30 knots is, therefore, about 34,000, corresponding to 68,000 horse-power indicated. Allow- ing for the frictional correction, this would drop to about 62,000 horse-power, or 4°4 horse-power per ton. For the destroyer at 30 knots the resistance is about 174 tons; the effective horse-power is 3600, and the indicated horse-power about 6000, or 20 horse-power per ton, nearly five times as great as the corresponding power for the large ship. But while the destroyer under her trial conditions actually reaches 30 knots, it is certain that in the large ship neither weight nor space could be found for machinery and boilers of the power required for 30 knots, and of the types usually adopted in large cruisers, in association with an adequate supply of fuel. The explanation of the methods by which the high speed is reached in the destroyer has already been given. Her propelling apparatus is about one-fourth as heavy in relation to its maxi- mum power, and her load is only about one-third as great in relation to the displacement, when compared with the corre- sponding features in a swift modern cruiser. It will, of course, be understood that in practice, under existing conditions, a cruiser of 14,000 tons would not be'made 765 feet long, but probably about 500 feet. The hypothetical cruiser has been introduced simply for purposes of comparison with the destroyer. The earlier theories of resistance assumed that the resistance experienced by ships varied as the square of the speed. We now know that the frictional resistances of clean-painted sur- faces of considerable length vary as the 1°83 power of the speed. This seems a small difference, but it is sensible in its effects, causing a reduction of 32 per cent. at 10 knots, nearly 40 per cent. at 20 knots, and 42 per cent. at 25 knots. On the other hand, it isnow known that the laws of variation of the residual or wave- making resistance may depart very widely from the law of the square of the speed, and it may be interesting to trace for the typical destroyer how the resistance actually varies. Take first the otal resestance. Up to 11 knots it varies nearly as the square of the speed; at 16 knots it has reached 234 the cube; from 18 to 20 knots it varies as the 3°3 power. Then the index begins to diminish; at 22 knots it is 2°7 ; at 25 knots it has fallen to the square, and from thence to 30 knots it varies, practically, as does the frictional resistance. The residual resistance varies as the square of the speed up to 11 knots, as the cube at 12} to 13 knots, as the fourth power about 144 knots, and at a higher rate than the fifth power at 18 knots. Then the index begins to fall, reaching the square at 24 knots, and falling still lower at higher speeds. It will be seen, therefore, that when this small vessel has been driven up to 24 or 25 knots by a large relative expenditure of power, further increments of speed are obtained with less pro- portionate additions to the power. Passing from the destroyer to the cruiser of similar form but of 14,100 tons, and once more applying the ‘‘scale of comparison,” it will be seen that to 25 knots in the destroyer corresponds a speed of 474 knots in the large vessel. In other words, the cruiser would not reach the condition where further increments of speed are obtained with comparatively moderate additions of power until she exceeded 47 knots, which is an impossible speed for such a vessel under existing conditions. The highest speeds that could be reached by the cruiser with propelling apparatus of the lightest type yet fitted in large sea-going ships would correspond to speeds in the destroyer, for which the resistance is varying as the highest power of the speed. These are suggestive facts. Frictional resistance, as is well known, is a most important matter in all classes of ships and at all speeds. Even in the typical destroyer this is so. At 12 knots the friction with clean- painted bottom represents 80 per cent. of the total resistance ; at 16 knots 70 per cent ; at 20 knots a little less than 50 per cent. ; and at 30 knots 45 per cent. If the coefficient of friction were doubled and the maximum power developed with equal efficiency, a. loss of speed of fully 4 knots would result. In the cruiser of similar form the friction represents 90 per cent. at 12 knots, 85 per cent. at 16 knots, nearly 80 per cent. at 20 knots, and over 70 per cent. at 23 knots. If the coefficient of friction were doubled at 23 knots and the corre- sponding power developed with equal efficiency, the loss of speed would approximate to 4 knots. These illustrations only confirm general experience that clean bottoms are essential to economical propulsion and the main- tenance of speed, and that frequent docking is necessary in vessels with bare iron or steel skins, which foul in a compar- atively short time. Possibilities of further Increase tn Speed. From the facts above mentioned it is obvious that the increase in speed which has been effected is the result of many improve- ments, and has been accompanied by large additions to size, engine-power and cost. These facts do not discourage the “inventor,” who finds a favourite field of operation in schemes for attaining speeds of 50 to 60 knots at sea in vessels of moderate size. Sometimes the key to thisremarkable advance is found in devices for reducing surface-friction by the use of wonderful lubricants to be applied to the wetted surfaces of ships, or by interposing a layer of air between the skins of ships and the surrounding water, or other departures from ordinary practice. Ifthese gentlemen would ‘‘condescend to figures,” their estimates, or guesses, would be less sanguine. In many cases the proposals made would fail to produce any sensible re- duction in resistance ; in others they would increase resistance. Other proposals rest upon the idea that resistance may be largely reduced by adopting novel forms, departing widely from ordinary ship shapes. Very. often small-scale experiments, made in an unscientific and inaccurate manner, are adduced as proofs of the advantages claimed. In other instances mere assertion is thought sufficient. . Ordinarily no regard is had to other con- siderations, suchas internal capacity, structural weight and strength, stability and seaworthiness. Most of these proposals do not merit serious consideration. Any which seem worth investigation can be dealt with simply and effectively by the method of model experiments. A striking example of this method will be found in the unusual form of a Parliamentary Paper (No. 313, of 1873), containing a report made by Mr. William Froude to the Admiralty. Those interested in the subject will find therein much matter of special interest in con- | section with the conditions attending abnormally high speeds. It must suffice now to say that ship-shaped forms are not likely to be superseded at present. NO. 1561, VOL. 60] NATCORE [SEPTEMBER 28, 1899 The most prolific ‘‘inventions” are those connected with supposed improvements in propellers. One constantly meets with schemes guaranteed by the proposers to give largely in- creased efficiency and corresponding additions to speed. Varia- tions in the numbers and forms of screws or paddles, the use of jets of water or air expelled by special apparatus through suit- able openings, the employment of explosives, imitations of the fins of fishes and numberless other departures from established practice are constantly being proposed. As a rule the ‘‘in- ventors”’ have no intimate knowledge of the subject they treat, which is confessedly one of great difficulty. When experiments are adduced in support of proposals they are almost always found to be inconclusive and inaccurate. More or less mathe- matical demonstrations find favour with other inventors, but they are not more satisfactory than the experiments. An air of great precision commonly pervades the statements made as to possible increase in efficiency or speed. I have known cases where probable speeds with novel propellers have been esti- mated (or guessed) to the third place of decimals. In one such instance a trial was made with the new propeller, with the result that instead of a gain in efficiency there was a serious loss of speed. Very few of the proposals made have merit enough to be subjected to trial. None of them can possibly give the benefits claimed. It need hardly be added that in speaking thus of so-called “inventors” there is no suggestion that improvement has reached its limit, or that further discovery is not to be made. On the contrary, in regard to the forms of ships and propellers, continuous investigation is proceeding and successive advances are being made. From the nature of the case, however, the difficulties to be surmounted increase as speeds rise; and a thorough mastery of the past history and present condition of the problems of steamship design and propulsion is required as a preparation for fruitful work in the nature of further advance. It would be idle to attempt any prediction as to the charac- teristic features of ocean navigation sixty years hence. Radical changes may well be made within that period. Confining at- tention to the immediate future, it seems probable that the lines of advance which I have endeavoured to indicate will remain in use. Further ‘reductions may be anticipated in the weight of propelling apparatus and fuel in proportion to the power de- veloped ; further savings in the weight of the hulls, arising from the use of stronger materials and improved structural arrange- ments ; improvementsin form; and enlargement in dimensions. If greater draughts of water can be made possible, so much the better for carrying power and speed. For merchant vessels commercial considerations must govern the final decision ; for warships the needs of naval warfare will prevail. It is certain that scientific methods of procedure and the use of model ex- periments on ships and propellers will become of increased importance. Already avenues for further progress are being opened. For example, the use of water-tube boilers in recent cruisers and battleships of the Royal Navy has resulted in saving one-third of the weight necessary with cylindrical boilers of the ordinary type to obtain the same power, with natural draught in the stokeholds. Differences of opinion prevail, no doubt, as to the policy of adopting particular types of water-tube boilers ; but the weight of opinion is distinctly in favour of some type of water-tube boiler in association with the high steam pressures now inuse, Greater safety, quicker steam-raising and other advantages, as well as economy of weight, can thus be secured. Some types of water-tube boilers would give greater saving in weight than the particular type used in the foregoing comparison with cylindrical boilers. Differences of opinion prevail also as to the upper limit of steam pressuré which can with advantage be used, taking into account all the conditions in both engines and boilers. From the nature of the case, increases in pressure beyond the 160 fo 180 lbs. per square inch commonly reached with cylindrical boilers cannot have anything like the same effect upon economy of fuel as the corresponding increases have had, starting froma lower pressure. Some authorities do not favour any excess above 250 lbs. per square inch on the boilers ; others would go as high as 300 Ibs., and some still higher. 4 Passing to the engine-rooms, the use of higher steam-pressures and greater rates of revolution may, and probably will, produce reductions in’ weight compared with power ©The use of stronger materials, improved designs, better balance of the moving parts, and close attention to details have tended in the SEPTEMBER 28, 1899 | same direction without sacrifice of strength. Necessarily there must be a sufficient margin to secure both strength and endur- ance in the motive power of steamships. Existing arrange- ments are the outgrowth of large experience, and new de- partures must be carefully scrutinised. The use of rotary engines, of which Mr. Parsons’ turbo-motor is the leading example at present, gives the prospect of further economies of weight. Mr. Parsons is disposed to think that he could about halve the weights now required for the engines, shafting, and propellers of an Atlantic liner while securing proper strength and durability. If this could be done in association with the use of water-tube boilers it would effect a revolution in the design of this class of vessel, permitting higher speeds to be reached without exceeding the dimensions of existing ships. It does not appear probable that, with coal as the fuel, water- tube boilers will surpass in economy the cylindrical boilers now in use ; and skilled stoking seems essential if water-tube boilers are to be equal to the other type in rate of coal consumption. The general principle holds good that as more perfect me- chanical appliances are introduced, so more skilled and dis- ciplined management is required in order that the full- benefits may be obtained. In all steamship performance the ‘* human factor” is of great importance, but its importance increases as the appliances become more complex. In engine-rooms the fact has been recognised and the want met.’ There is no reason why it should not be similarly dealt with in the boiler- rooms. : Liquid fuel is already substituted for coal in many steamships. When sufficient quantities can be obtained it has many obvious advantages over coal, reducing greatly manual labour in em- barking supplies, conveying it to the boilers and using it as fuel. Possibly its advocates have claimed for it greater economical advantages over ceal than can be supported by the results of extended experiment. Even if the saving in weight for equal evaporation is put as low as 30 per cent. of the corresponding weight of coal, it would amount to 1000 tons on a first-class Atlantic liner. This saving might be utilised in greater power and higher speed, or in increased load. There would be a sub- stantial saving on the stokehold staff. At present it does not appear that adequate supplies of liquid fuel are available. Com- petent authorities here and abroad are giving attention to this question, and to the development of supplies. If the want can be met at prices justifying the use of liquid fuel, there will undoubtedly be a movement in that direction. Stronger materials for the construction of hulls are already available. They are, however, as yet but little used, except for ~special classes of vessels. Mild steel has taken the place of iron, and effected considerable savings of weight. Alloys of steel with nickel and other metals are now made which give strength and rigidity much superior to mild steel, in association with ample ductility. For destroyers and torpedo boats this stronger material is now largely used. It has also been adopted for certain im- portant parts of the structures of recent ships in the Royal Navy. Of course the stronger material is more costly, but its use enables sensible economies of weight to be made. It has been estimated, for example, that in an Atlantic liner of 20 knots average speed about 1000 tons could be saved by using nickel steel instead of mild steel. This saving would suffice to raise the average speed more than a knot, without varying the dimensions of the ship. Alloys of aluminium have also been used for the hulls or portions of the hulls of yachts, torpedo-boats, and small vessels. Considerable savings in weight have thus been effected. On the other hand, these alloys have been seriously corroded when ex- posed to the action of sea-water, and on that account are not likely to be extensively used. Other alloys will probably be found which will be free from this defect, and yet unite lightness with strength to a remarkable degree. Other examples. might be given of the fact that the metal- lurgist has by no means exhausted his resources, and that the shipbuilder may look to him for continued help in the struggle to reduce the weights of floating structures. It is unnecessary to amplify what has already been said as to possible increase in the efficiency and types of propellers. With limited draught, as speeds increase and greater powers have to be utilised, multiple propellers will probably come into use. Mr. Parsons has shown how such problems may be dealt with ; and other investigators have done valuable work in the same direction. In view of what has happened and is still happening, it is NO. 1561, VOL. 60] NATURE 535 practically certain that the dimensions of steamships have not yet attained a maximum. Thanks to mechanical appliances, the largest ships built or to be built can be readily steered and worked. In this particular difficulties have diminished in recent years, notwithstanding the great growth in dimensions. Increase in length and weight favour the better maintenance of speed at sea. The tendency, therefore, will be to even greater regularity of service than at present. Quicker passages will to some extent diminish risks, and the chance of breakdown will be lessened if multiple propeilers are used. Even now, with twin screws, the risk of total breakdown is extremely small. Whatever may be the size and power of steamships, there must come times at sea when they must slow down and wait*for better weather. But the larger and longer the vessel, the fewer will be the occasions when this precaution need be exercised. It must never be forgotten that as ships grow in size, speed, and cost, so the responsibilities of those in charge increase! The captain of a modern steamship needs remarkable qualities to perform his multifarious duties efficiently. The chief engineer must have great powers of organisation, as well as good technical knowledge, to control and utilise most advantageously the men and machinery in his charge. Apart from the ceaseless care, watchfulness and skill of officers and men, the finest ships and most perfect machinery are of little avail. The ‘‘ human factor ? is often forgotten, but is all-important. _ Let us hope that in the future, as in the past, as responsibilities increase so will the men be found to bear them. NOTES. A STATUE, erected in memory of the late M. F. Tisserand, will be unveiled at Nuits-Saint-Georges on October 15. Major RONALD Ross has sent Mr. A. L. Jones a letter from Sierra Leone on his investigations into the cause of malaria. In the course of the communication he says:—We have now practically finished our work here. We have found—(a) that local species of Anopheles (mosquitoes) carry malaria ; (6) that these species breed in a few stagnant puddles. For many scientific reasons we have come to the conclusion that the truly malarial fever is caused here solely by the mosquito—probably entirely by the Anopheles species. We estimate then that most of the malarial fever here can be got rid of at almost no cost except of a little energy on the part of the local authorities. A SUCCESSION of earthquake shocks occurred on Monday night, September 25, in the district of Darjeeling, involving great loss of life and damage to property. No details as to the exact times of the shocks have been received. The earthquake was accompanied by a remarkable rainfall, and was followed by extensive landslips. It is reported that in twenty-four hours over 20 inches of rain fell, and in all 28 inches fell in thirty- eight hours. THE associate editorship of the American Journal of Science, vacant by the death of Prof. Marsh, has been taken up by Prof. L. V. Pirsson, of Yale College. IN a report just issued on metalliferous mines in the North Wales district, Dr. C. Le Neve Foster refers to the fact that several foreign companies have lately purchased mines in that district with the object of reworking them. He remarks :— “ Though I welcome the advent into Wales of the famous Vieille Montagne Company, for I have hopes that its methods of mining and dressing will form useful object-lessons to us, Tam not blind to the slur which is cast upon us as a mining nation. If such a capable body of commercial men as the directors of the Vieille Montagne Company propose to resuscitate some of our abandoned mines, it may be taken for granted that they consider the enterprise as likely to be profitable. Is our mining talent so far behind the times that foreigners can make a profit out of mines which we have abandoned as worthless? If so, the 536 NATURE [SEPTEMBER 28, 1899 technical skill of continental mining engineers is of a higher nature than that of our own people, and we are not keeping pace with the times. It therefore behoves us as a nation to get out of the groove of the slovenly old-fashioned methods of working ore mines, which linger so long in this country, and to give our mining superintendents and mining foremen such technical train- ing as will render them at least the equals of their continental competitors.” It is to be hoped that this note of warning will lead British mining companies to make use of the resources which modern science has placed at their disposal. THE Journal of the Society of Arts announces that among the prizes offered by the French Société d’Encouragement pour Industrie Nationale, open to all the world except members of the administrative council, and to be awarded next year, are the following :—Two thousand francs (8o/.) for a publication useful to the chemical or metallurgical industry, a treatise on metal- lurgical chemistry summarising the works that have appeared on the subject during the last twenty years being invited; two prizes of 500 francs (20/.) each for scientific chemical researches the results of which are useful to industry, the authors not being required to have realised the practical applications which they may foresee as resulting from their observations ; 2009 francs (80/.) for the scientific study of an industrial process the theory of which is still imperfectly known, the methods that permit of obtaining a given result being often known long before the nature of the phenomena is suspected, and yet the knowledge of which has great interest as regards reducing the number of empirical trials necessary for realising fresh improvements ; and 3000 francs (120/.) for the production of permanent magnets, the qualities expected from which are power and stability. The models, papers, descriptions, &c., must be sent in before December 31 to the Secretary of the Société d’Encouragement, 44 Rue de Rennes, Paris. THE death is announced of Mr. Edward Case, the author of a paper on ** The Dymchurch Wall and Reclamation of Romney Marsh,” read at the recent meeting of the British Association. For many years Mr. Case was a superintending engineer in the Public Works Department in Ceylon. Of late he gained dis- tinction in the engineering world by his investigations of the problem of sea defence, and by the results which he had obtained on a variety of shores. THE Funafuti Boring Expedition has very recently led to the rectification of a common ethnographical error, and the discovery of an interesting fact in zoo-geography. In the Monograph on the Atoll of Funafuti published by the Australian Museum, Sydney (part iii. 1897, p. 199) Mr. E. R. Waite referred to a large undetermined fish known to the natives as ‘ Palu,” and to traders as ‘* Oil-fish.” According to Mr. Louis Becke, a full-grown Palu would weigh up to 150 lbs. and be 6 feet long ; the average size is about 3 or 4 feet, and weight 4o to 60 lbs. The natives have many superstitions in regard to Palu; every portion of it is edible, even the head and bones when cooked turning into a rich mass of jelly. The flesh of the Patu, if left uncooked, never putrefies ; it simply dissolves into a colourless and odourless oil. Perhaps the great regard the natives have for it is due to the fact of its being a rapid and powerful purga- tive. It is a deep-water fish, and is usually caught at a depth of from 120 fathoms down to 200 fathoms ; the fishing is only done at night. The Palu fishing-hook has been described by Mr. C. Hedley (¢.c. part iv., 1897, p. 272), who points out that this large hook, which is widely distributed in the Central Pacific, and may be seen in most ethnographical collections, has been described by all authors as a ‘* shark-hook.” The last expedition to Funafuti has been fortunate enough to obtain a specimen of this fish, and in an appendix (part ix., 1899, p- 539) Mr. Waite has solved NO. 1561, VOL. 60] the riddle, and found that this mysterious fish is the well-known Ruvetlus pretiosus, which hitherto was known only from the North Atlantic, and whose recorded range is now enormously increased. The Escolar (Atlantic name) has been taken at depths as great as 300 and 400 fathoms, but can be taken only at night in September and the early part of October. WE learn from the September number of Aznalen der Hydro- graphie that the Deutsche Seewarte, in conjunction with the Berlin Meteorological Office, proposes to issue a ten-day report, containing values of barometric pressure, air-temperature and rainfall for, say, one hundred stations between the west coast of North America and the east coast of Asia, accompanied by a map showing observations taken on board German ships traversing the NorthAtlantic. The report would be issued as a supplement to the Daily Weather Bulletin, about twenty days after date. The success of the proposal will toa great extent depend upon the willingness of other countries to furnish ten-day means for some selected stations in their respective systems. WE have received from Dr. W. Doberck, Government Astronomer, Hong Kong Observatory, his annual report for 1898. The ‘‘ Observations and Researches ” contain synopses of fifteen years’ meteorological and magnetic observations and a number of very useful tables relating to the climatology of the Colony. THE papers read at the ninth annual general meeting of the Museums Association, held in Sheffield in July of last year, are contained in the ‘‘ Report of Proceedings,” just published by Messrs. Dulau and Co. All the subjects dealt with are of interest to every one concerned in museum work, among them being: the relation of museums to elementary education ; the arrangement of museum herbaria, the electric light installation at the Manchester Museum, the exhibition of museum speci- mens, the mounting of marine animals as transparencies for museum purposes, the ethnological arrangement of archzeo- logical material, and some Russian museums. Mr. Herbert Bolton, the editor of the volume, calls attention to the need for a complete report or directory of museums in the United King- dom, and rightly remarks that ‘‘ the publication of such a re- port, and its annual revision, would tend to bring museums into clese union and to a common knowledge of each other.” It is pointed out that the preparation of an annual report of this character might be undertaken by a committee of the British Association ; and this suggests that it would be worth considering whether the Museums Association itself might not with advan- tage become part of the British Association, in much the same way as the Corresponding Societies are at present. The multi- plication of annual meetings would thus be avoided, and ex- cellent opportunity would be afforded for the discussion of the various aspects of museum work. In No. 4 of vol. i. of the ‘*‘ Geological Series”’ of the Field Columbian Museum Mr. Elmer S. Riggs treats of the Mylagau- lidee, an extinct family of rodents of which two new genera are described. It is remarked that the one prominent feature in these animals is the unusual development of the premolar to the exclusion of the posterior-lying teeth, evincing unusual capacity for crushing or grinding. A fossil egg from South Dakota is described in No. 5, by Dr. Oliver C. Farrington. The specimen is about 2 inches long by 14 inches. Covering most o: the exterior is a thin black layer ‘017 of an inch in thickness, and resembling an eggshell. The mass of the specimen is chal- cedony, and this contains a white opalescent ovoid mass which appears to correspond with the yolk, and to yield evidence of organic matter. In shape this petrified egg resembles that of the Florida duck. SEPTEMBER 238, 1899] NWA LURE 537 THE jumping-mice of the genus Zapus form the subject of part 15 of the ‘‘North American Fauna,” edited by Dr. Merriam. It is noteworthy that whereas Dr. Coues in 1877 re- cognised but a single representative of this genus, ranging over a large area in North America, Mr. Preble, the author of the present memoir, considers himself justified in distinguishing no less than twenty North American species and sub-species, in ad- dition to one Old World form recently described from Szechuan. The discovery of the Szechuan species adds one more link in the chain connecting the fauna of North-eastern Asia and North America; and when Manchuria and Mongolia are fully ex- plored, representatives of the genus may be looked for in those countries. ANOTHER important contribution to our knowledge of the North American mammal fauna is afforded by Dr. Allen’s revision of the squirrels inhabiting the area north of Mexico, published in the August number of the American Naturalist. The last revision was in 1877, when six species and seven sub-species were recognised ; Dr. Allen now admits ten species, witha large number of sub-species. With Mr. Nelson’s revision of the species inhabiting Mexico and Central America, the group is now placed on a satisfactory footing, except as regards South America. Interesting results have been obtained by both writers as regards the effects of temperature and humidity on the coloration of members of the group. ‘‘In the drier interior mountains,” for example, ‘‘certain sub-species of a group will be characterised by dull greyish upper-parts and white under- parts, while other sub-species of the same group inhabiting humid mountains near the coast will have nape and rump- patches sharply contrasting with the rest of the dorsal surface and bright ferruginous under-parts ; increased humidity within the tropics being usually accompanied by increased intensity of coloration.” This is zoology in its best sense. A NOTEWORTHY addition to the fauna of the Australasian region is afforded by the discovery of a representative of the genus Balanoglossus in the New Zealand seas, since it has hitherto been unknown in the southern hemisphere, as, indeed, was the entire group of the Hemichordata till Mr. T. P. Hill found a species of Ptychodera in 1893. The new Balanoglossus is de- scribed by Mr. Benham in the September number of the Quar‘. Journ. Microscopical Sctence, and presents all the characteristic features of the genus. We may remind our non-zoological readers that Baianoglossus includes worm-like animals which approximate to vertebrates in the possession of a notochordal tract.—The same journal contains an interesting paper by Mr. E. S. Goodrich, of Oxford, on the existence of a communication between the blood-vascular system and the ‘‘ccelom” in the common leech, YEr another communication in the journal above quoted can- not be passed over without notice, although, from the extremely technical nature of the subject, such mention must necessarily be brief. The paper in question, which has been awarded the Rolleston Memorial Prize for 1898, is one by Mr. R. Evans, on the structure and metamorphosis of the larva of the common freshwater sponge. The work, which occupied a large portion of the author’s time for a period of about eighteen months, was undertaken on the suggestion of Prof. Ray Lankester, and ap- pears to have been admirably carried out. Several types of free-swimming larve have been detected, and their mutual re- lationship determined. From the occurrence of so-called ‘‘collar- cells’ in sponges, and their early appearance in the free-swimming laryze, coupled with their absence in all the Metazoa, the author is inclined to believe that the Porifera (sponges) have no re- lationship with the former group, but are more probably derived independently from primitive flagellate organisms. NO. 1561, VOL. 60] IN their report for the year 1898 the Trustees of the Australian Museum, Sydney, deplore the insufficiency of the Government grant for purchase of specimens. It appears that in 1892, when the purchase grant was 1250/7, the Colony was passing through a period of financial depression, in consequence of which the vote was reduced in the following year to 200/ , this small amount having to suffice for the purchase of books as well as specimens. Although this amount has been slightly increased in the vote for 1898-99, the Trustees point out that it is altogether insufficient for the needs of the institution, so that many specimens are lost to the museum, while collecting has had to be suspended altogether. As the opportunity to acquire many of the ethnological specimens offered will never recur, it is to be hoped that Government, now that the finances of the Colony have taken such a decided turn for the better, may see their way to place the Trustees in a stronger position for carrying out the purposes for which the museum was founded. Mucu more satisfactory reading than the foregoing is Dr. E. Thurston’s report on the Madras Museum for 1898-99 As was fully stated in NATURE for May 26, 1898, the Director has been chiefly occupied in the investigation of the ethnology of the numerous native tribes of the Nilgiri and Anamalai Hills; the results of which are in course of publication in a series of valuable memoirs. Attention is directed in the report to the prospect of acquiring Mr. R. B. Foote’s well-known col- - lection of prehistoric Indian implements. _ It is also satisfactory to learn that the importance of fishery investigations is fully recognised by the Director. Messrs. HoLporn AND Day send usa reprint from /Vcede mann's Annalen dealing with their investigations on the air-ther- mometer at high temperatures, a subject to which attention has been drawn by the recent discussions on platinum-thermometry at the British Association. The authors give comparisons of the results obtained by using containing vessels of platinum, iridium and porcelain respectively in these observations. From Messrs. O. Lummer and E. Pringsheim we have received a copy of their paper on the partition of energy in the spectrum of a black body, published in the Verhandlungen on the German Physical Society (1). Experiments are described in which the radiations from an electrically heated cylinder were allowed to fall on a bolometer, and the energy tabulated for different temperatures and wave-lengths, the results being compared with those given by Paschen’s formula. In the course of a paper on Euclidian geometry, contributed to the Bulletin de la Classe des Sciences (Brussels), M. Charles Lagrange remarks that the condition necessary for introducing doubts in geometry, a condition without which no argument exists against the certainty of Euclidian space, would consist in. presenting two different admissible definitions of space. Up till now only one definition has been given; and this assumes. the existence of Euclidian space. The author considers tha the new geometry has in fact established the contrary of what it claimed ; it has attempted to throw doubts on the physical! reality of the Euclidian postulate, and it has only succeeded in confirming it. ENGLER AND PRANTL’S great work, Die natiirlichen Pflan~ senfamilien is now completed, as far as flowering plants are. concerned, by the publication of Nos. 184-5, completing Parts il.—v. Pror. D. G. FAIRCHILD, or the U.S. Department of Agri- culture, gives, in the Bolanzcal Gazette for August, an interesting: sketch or the general features of the flora of Venezuela, derived from his experience as botanist to the expedition fitted out by 538 NATURE [SEPTEMBER 28, 1899 Mr. Barbour Lathrop, of Chicago, for the exploration of that country, In honour of the 150th anniversary of the birth of Goethe (August 28, 1899), Dr. H. Potonié reprints, from his Matur- wessenschaftliche Wochenschreft, a treatise on the morphological origin of the leaves of plants. The importance is shown of the part played by Goethe’s theory of metamorphosis in the elucid- ation of problems connected with vegetable morphology, and it is pointed out that the introduction of the term ‘‘ morphology ” itself is due to Goethe. VOLUME XV., part 7 of the Mouveaux mémotres de la Soc. Imp. des Naturalistes de Moscou is chiefly occupied by a mono- graph of the genus Spheronema (Ascomycetes) by M. A. Jaczewski. He enumerates and describes seventy-two good specimens of the genus, seventy-seven being rejected as not properly belonging to it, besides eight others, for which a?new genus, Pseudographium, is formed. D. Strémonkhoff has also a short paper on the ammonites Phyloceras zignodianum and Lytoceras adelae, from the schists of Balaclava. Pror. VERNON L. KELLOGG gives an interesting account, in the American Naturalist for August, of the Hopkins Sea-side Laboratory on the Bay of Monterey, connected with the Leland Stanford Junior University. Monterey Bay and the Bay of Naples are stated to be much alike in the abundance and representation of species. The Bay is a middle point between the north and south zones of the Pacific coast. The regular sessions of the laboratory are held in June and July of each year ; but investigators and students working without instruc- tion may continue their work though the summer. Courses of lectures are given in general zoology, embryology and crypto- gamic botany. PRACTICAL directions for stuffing and setting up birds are given in ‘‘ Bird Stuffing and Mounting,” the fifth edition of which has been published by Messrs. J. and W. Davis, Dart- ford. To students of natural history and collectors this practical manual of taxidermy should be of service, _ IN connection with the Parents’ National Education Union, a course of lectures to young people will be delivered by Mr. Cecil Carus- Wilson at the Horbury Rooms, Notting Hill Gate, during this month and next, The titles of the lectures are “The Wonders of Rain,” ‘Ice and Glaciers,” ‘*The Mighty Ocean,” ‘‘ Volcanoes and Geysers.” The aim will be to interest and entertain children by directing their attention to the natural phenomena which surround them, and upon which the studies of geography, geology and physiography are based. THE additions to the Zoological Society’s Gardens during the past week include a Macaque Monkey (Aacacus cynomolgus, 6 ) from India, presented by Dr. Montgomery Smith; an African Civet Cat (Wiverra czvetta) from West Africa, presented by Mr. W. H. Hardwick, R.N.; a Two-spotted Paradoxure (Nandinia binotata) from West Africa, presented by Mr. F. Gordon ; a Black-backed Kaleege (Zuplocamus melanonotus, ? ), two Sonnerat’s Jungle Fowls (Ga//us sonnerat?, 2 9), a Wood Francolin (Francolinus gularts) from India, presented by Mr. W. F. Pedler ; four Green Lizards (Lacerta viridis), European, presented by Mr. F. K. Preston; two Black-eared Marmosets (Hapale penicillata) from South-east Brazil, a Hocheur Monkey (Cercopithecus micticans), a Ruppell’s Parrot (Paeocephalus rueppellt) from West Africa, a Maroon Oriole (Oriolus tratliz) from India, two Radiated Tortoises (Zestado radiata) from Madagascar, deposited. NO. 1561, VOL. 60] | sible. OUR ASTRONOMICAL COLUMN, ~ ' New ALGOL VARIABLE IN CyGNus.—The following szznima occur at convenient times for obseryation during October :— R.A. 20h. 2°4m. D.M. + 45° "3062. Decl. + 45° 53' (1855) d. h, m W alli ny moh 1899: ‘Oct. 5 ‘8 43 1899. Oct. 23 15 43 22 ” 14 12 13 2” »” 28 5 28 STELLAR PARALLAX.—M. Osten Bergstrand, of the Upsala Observatory, has recently been engaged in measuring photo- graphic chart plates to determine any possible evidence of stellar parallax (Astr. Mach., Bd. 150, No. 3593). The photographs were taken with the photographic refractor of 33 cm. aperture and 4°33 metres focal length during 1897 and 1898, all the measures being made with a Repsold micrometer in conjunction with a “‘reseau”’ by Gautier. After describing the method of measurement adopted, the following values for parallax are given :— Star. Parallax. : = 1516 A, + o”-080 + oorr, ... From measures of four comparison stars on } fourteen plates. A Oe. 11677.::. + O”*192 + O''013. ... From measures of 3 ie eight comparison } stars on zzze plates, The latter star is remarkable as having a very large proper motion—about' 3” annually. PRECESSION TABLES.—We have received a volume compiled by Dr. Downing, superintendent of the English Nautical Almanac, containing a series of tables which have been con- structed so as to give the values of the precessions corresponding to Newcomb’s value of the Precessional Constant, as deduced by him in accordance with the request made to him at the International Conference on Fundamental Stars, held in Paris in May 1896. “Prof. Newcomb’s original ‘results are published in the Astronomical Papers of the American Ephemeris, vol. viii. parti. The present tables are constructed for Epoch 1910'0, but the method of setting out is such that they can be used with facility, for at least ten years before and after that date. LONGITUDE FROM MOON CuLMINATIONS. —In a communica- tion to the Royal Astronomical Society ( 1/o2¢hly Notices, R.A.S., vol. lix. p.'§13,' May 1899), Mr. D. A. Pio, of Syra, Greece, brings forward.a new method of determining local longitude. The determination of culmination is only undertaken to give the precise instant of the moon’s transit across the local meridian, thereby obviating the necessity of an accurately adjusted transit instrument with the many precautions connected with it. The instruments required are a sextant, artificial horizon, and a well- rated chronometer, together with the usual tables. Instead of finding the right ascension of the moon directly as usual, the author obtains it indirectly by finding the mean local time of meridian passage, converting to sidereal time, and then adding the right ascension of the mean sun at local transit. The difficulty of finding the mean local time of transit is got over by observations of equal altitudes, the resulting ¢zmze of culmination requiring to be corrected to reduce it to ¢zze of transit, Local mean time is'determined by similar measures of equal altitudes of the sun. The difference between the times of transit of sun and moon thus obtained is, of course, the mean local time of the moon’s transit. The remaining calculations are precisely similar to the usual method of lunar distances, so that the novelty of the new method consists in the substitution of the use of ** equal altitudes’ with a sextant for meridian passage with a transit circle; in fact the observation is really a chronometric one. The difference in time between the transits of sun and moon should be correct to the ¢ez¢h of a second, and to facilitate this the two observations should be chosen as near together as pos- The method is stated to be unsuitable for high latitudes. The necessary formul for ‘‘ reduction to meridian ” are included in the article, and an example fully worked out to illustrate the exact method of procedure. SEPTEMBER 28, 1899] THE ROVAL PHOTOGRAPHIC SOCIETY’S EX AIBITION. HE forty-fourth annual exhibition of the Royal Photographic Society was opened to the public last Monday at the Gallery of the Royal Society of Painters in Water Colours, 5 Pall Mall East. As is usual, by far the greater number of the exhibits claim‘attention on account of their pictorial interest ; but the technical and scientific section is considerably larger than it has been at the recent exhibitions. No doubt next year there will be a still further increase in the importance of this section, as the Society will then have at their disposal the larger accommodation available at the New Gallery in Regent Street. The judges in this Section, Captain Abney, Mr. T. Bolas and Mr. Chapman Jones, have selected three of the exhibits as showing progress of sufficient importance to merit the special distinction of receiving the Society’s medal Taking these as they stand in the catalogue, the first is awarded for copies of an etching, a mezzotint, a silver print, an engraving, a lithograph, a pen and ink drawing and a pencil drawing, by Mr. J. Hort Player, by what he calls the ‘‘absorption” process. The method is to place the picture or document that is to be copied face uppermost, to lay upon it a piece of ‘‘ bromide paper ” with its sensitive surface in close contact with the picture, and then to expose with the bromide paper towards the light, so that the light passes through the sensitive surface before it comes in con- tact with the picture being copied. On development this fur- nishes a negative from which prints are obtained as usual. The great advantage of the process is that the picture or docu- ment need not be transparent, or if it is on ordinary paper there may be other writing or drawing on the reverse side. Those who examine these specimens of Mr. Player's will be surprised at the wonderful perfection to which he has brought the process, and its universal applicability is proved by the great variety in the character of the originals that he has | worked from, Another medal is awarded for a cross-lined screen for use in the making of half-tone photo-typographic blocks, by Messrs. J. E. Johnson and Co. It has two hundred lines to the inch over its whole area of thirteen by sixteen inches, the especial feature of the screen being the great regularity of the ruling and the free- dom from blemishes in so large a plate. Two still larger ruled screens are also shown by the same firm, of 133 and 150 lines to the inch respectively. Mr. E. Sanger Shepherd receives a medal for his ‘‘ tri- chromatic light filters.” The three-colour printing methods that have been brought to such perfection depend upon the fact that the phenomena of colour vision can be explained on the assumption of three colour sensations. By photographing separ- ately the light that affects each of these, and superposing the prints from the negatives, each being printed in its corresponding colour, the same sensation of colour will be produced by the resulting composite print as by the original. In order to photo- graph separately the colours that correspond to each sensation it is necessary to stop the light that is not wanted by means of a suitably coloured screen, which is generally placed against the lens. But these colour screens have also to compensate for the differences between the sensitiveness of the plate used for the different colours and their visual intensity. Heretofore we believe the colour screens have been prepared by the method of trial and error, and though astonishingly good results have sometimes been produced, we may well expect greater certainty and more definite success by the use of screens that have been adjusted by definite methods of measurement as these of Mr. Sanger Shepherd’s have been. Cadett ‘‘rapid spectrum plate” and tested by the colour sensitometer recently devised by Captain Abney. The exact tints are obtained by the superposition in each case of films variously dyed. Among the cameras shown, the ‘‘ Gambier-Bolton” hand camera by Messrs. Watson and Sons is worthy of especial attention, as embodying the requirements found by Mr. Bolton in his large experience in photographing animals, The camera is for 5 x 4 inch plates, and is by no means a compact apparatus suitable for carrying about for obtaining snap-shots. It is designed for lenses of much greater focal length than usual that the image may be large, and as the lenses must be rapid, they must be large and consequently heavy. The camera has many conveniences adapting it to the special work it is constructed for. The same exhibitors show the ‘*Kromaz” colour ap- paratus. This is somewhat analogous to Ives’ well-known NO. 1561, VOL. 60] The screens are adjusted to the | WATURE 539 ‘*Kromscop,” its only merit presumably being that it is cheaper. Instead of taking a complete stereoscopic negative for each of the three colours, only two pairs of negatives are taken—one through a green screen, and one of the other pair through a red and the other through a blue screen. The view shown iscrude, and hardly comparable with the exquisite results obtained with Ives’ ‘* Kromscop.” The Lippmann interference colour process is exemplified by three photographs by Mr. Edgar Senior—two views and a spectrum of the arc light. These would show to better advan- tage if the correct position of the eye were indicated in each case. The views are very good specimens of the results ob- tainable by this method, but the spectrum is especially worthy of commendation. In addition to these there will be found upon the tables many little conveniences, some of a distinctly novel kind, that will prove of service to those who photograph either for scientific purposes or for mere pleasure. A small printing frame, with six slides so that the sensitive surface may be exposed in six separate strips, is exhibited by Messrs. Marion and Co., and is applicable to a great variety of experimental purposes; and a frame, by Mr. T. Webster, that opens like a book, the negative being entirely removed from the print, so that the whole of the print may be examined at any time, thoes perhaps not very novel in principle, is likely to prove useful. But the most remarkable of all the exhibits is not mentioned in the catalogue, although examples will be found on the tables. These are some plates prepared by General Waterhouse, the honorary secretary of the Society, to illustrate the fact that a polished surface of metallic silver is sensitive to light, and that the resulting latent image may be developed by mercury vapour, after the manner of daguerreotype plates, or by the methods of so-called physical development, after the manner of wet collodion plates. The exposures necessary are long, generally two to three hours, to direct sunshine in August. To exclude any effect of the stencil plate used as the negative to print from, a sheet of mica was placed between it and the silver surface, and the silver surfaces experimented with have been electroplated copper plates prepared for daguerreotype work, silver foil and commercial silvered glass, the surface in each case being polished with plate powder. The surfaces of other metals have given similar results. Many years ago Moser made similar ex- periments, developing the images with the vapour of water and of mercury, but (speaking without reference) we think that he did not go so far as to develop the images by the deposition upon them of silver from a solution. General Waterhouse seems to have brought these experiments and practical photography a little nearer together, and we shall receive with great interest any further results of his investigations. (At UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Dr. A. WILLEY, formerly Balfour Student of the University ot Cambridge, has been appointed Lecturer on Biology in Guy's Hospital. THE inaugural address of the coming session of the City and Guilds Central Technical College will be given at the College, in Exhibition Road, on Tuesday afternoon next, at three o'clock, by Sir Andrew Noble. Science makes the following announcement :—The plans for building the University of California, submitted by M. Bernard, of Paris, have received the first prize in the competition arranged by Mrs. Phoebe Hearst. The cost of the buildings is estimated at over 15,000,000 dollars. IN addition to 300,000 dollars subscribed from various sources for an endowment of Brown University, made on condition that 2,000,000 dollars be collected, Mr. John D. Rockefeller has offered to give 250,000 dollars on condition that 1,000,000 dollars be obtained before the commencement of next year. A PROSPECTUS just received shows that the work of the South African School of Mines, Kimberley, is now carried on in suit- able premises, which were completed in the beginning of this year at a cost of about 9o000/. Of this sum, 2000/. was given by the Government of Cape Colony, 2000/. by the De Beers Company, and 5000/. was borrowed. The school has been established to carry out part of a scheme for the training of 540 NATURE [SEPTEMBER 28, 1899 mining engineers in South Africa. The courses of instruction are intended to prepare students for a diploma of mining engineer, or for the degrees of B.Sc. or M.Sc. in mining engineer- ing. Theoretical and practical instruction is given, under the direction of the principal, Mr. James G. Lawn, in mining, mechanical and electrical engineering, metallurgy, assaying, sur- veying and other subjects. Practical work is carried on in the mines and workshops of the De Beers Company, and also in various mines at Johannesburg. The time spent at Johannesburg is devoted to a special study of the cyanide process in all its developments, of the electrical machines and appliances at the mine where the student is working, of the methods of assaying and surveying and of the economics of mining on the Rand, A thorough training for mining engineers is thus provided in connection with the school, the course of work described in the prospectus being of a very satisfactory character. Tue London Technical Education Board have arranged several advanced evening science courses in connection with King’s and University Colleges, to commence next month. The courses of instruction will afford an opportunity to students who can study only in the evenings to obtain instruction in well-equipped University laboratories, and will make available to evening students the same advantages as are enjoyed by University day students, but they are only intended for those who are practically engaged during the day in some trade, business or occupation.—A course of twenty lectures on civil engineering will be given by Prof. Robinson, at King’s College, on Mondays, from 7 to 9, commencing on Monday, October 9. Part of the time will be spent in working out engineering calculations by graphical methods.—A course of about twenty demonstrations will be given by Prof. Capper and Mr. H. M. Waynford, at King’s College, on Thursday evenings, 7 to 9, upen ‘‘ Steam and Gas Engines and Generai Laboratory Work,” commencing October 12. The latter portion of each evening will be devoted to experimental and practical work in the engineering laboratory in illustration of .the lectures. —A course of about twenty lectures*on mechanical -engineering will be given by Prof. Hudson Beare, at University «College, on Friday evenings from 7.30-9.30, commencing ‘Friday, October 13.—A special course of lectures on alternating currents will be given by Prof. Wilson, at King’s College, on Monday evenings, at 6.30 p.m., beginning October 9.—The following courses have been arranged to be held under the direction of Prof. Ramsay, at University College. In both of these courses the work will be oégéna/. (a) A course of twelve lectures on sewage and its purification, by Dr. Samuel Rideal, on Mondays, at 5.30 p.m., commencing November 6. - (4) A course of lectures on spectroscopy and spectrography will be delivered by Mr. E. C. C. Baly. SCIENTIFIC SERIAL. Wiedemann’s Annalen der Physik und Chemze, No. 8.— Limits of the solid state, by G. Tammann. Experiments on a mumber of organic bodies show that even when the heat of fusion is very nearly or accurately zero, the difference between the specific volumes of the liquid and the crystals is consider- able. —Magnetic properties of hematite, by A. Abt. The maxi- mum magnetic moments of three equal prisms, of pyrrhotite, hematite and magnetite respectively, were found to be in the ratio of I to 2°356 to 3'237. Pyrrhotite shows the smallest magnetisation in comparison with its percentage of metallic iron. —The blue steam-jet, by A. Bock. ; =. < . cales Sue om Notes . 5 3) I 8 cote SSS Our Astronomical Column :— New Algol Variable in ee es «+e SoS Stellar Parallax eae CREE Oo >. 6 0) SRS Precession Tables. . . . . > Let aS OS: Longitude from Moon Culminations PL: =» «| 538 The Royal Photographic Society’s Exhibition. By Cj; Re hoe. SS) University and Educational ‘Intelligence Ra Once fo, | SSK) Scientific Serial ... o 0 8 (POOR enw! So 549 Societies and Academies > Gy 0 Drees c 549 NATURE 541 THURSDAY, OCTOBER 5, 1899. BERTHELOT’S AGRICULTURAL CHEMISTRY. Chimie végétale et agricole. Par M. Berthelot. Four volumes. Pp. xvi + 511, vit 441, vi +517, vi + 528. (Paris: Masson, 1899.) HE ancient Chateau de Meudon, Seine-et-Oise, which was left in ruins at the end of the war of 1870, was thirteen years later converted into an agricultural experi- ment station by the French Government, and permanently attached to the Professorship of Organic Chemistry in the Collége de France. In the four bulky volumes now before us, the professor, M. Berthelot, has brought together an account of the various investigations carried out at the station between 1883 and 1899, under his direction, with the assistance in many cases of M. G. André. Besides these reports, the volumes contain an accomnt of several earlier investigations by M. Berthelot. We have in fact brought before us the whole of his investigations on plants, soils and various cognate matters, carried out during the last forty years. Agricultural chemists will heartily welcome the public- ation in sucha convenient form of this great mass of original investigation. M. Berthelot is well known as a first-class man of science, and as one of the most prolific and versatile workers of the present age. The new ideas he has brought forward concerning many obscure points in agricultural chemistry will be highly valued. Never- theless, those acquainted with the peculiarities of M. Berthelot’s work will not be surprised that a cautious critic is unable always to accept the conclusions to which he has apparently too easily arrived. The more startling and novel are the conclusions brought before us, the more thorough and unmistakable ought surely to be the basis of fact on which these conclusions are built. A few experiments, relating to only a part of the facts in ques- tion, must fail to carry conviction when new laws are propounded, or we are asked to surrender as a mistake views previously arrived at after much patient research. It will be gathered from what has just been said that the papers in the volumes before us are of unequal value. All the investigations are indeed highly suggestive, and no experimental investigator would desire one of them to be omitted ; but students of agricultural chemistry will not unfrequently find it advisable to examine with much care the evidence brought forward before accepting all the conclusions of the author. That we may do no injustice to the book we will, in the first place, call attention to the very valuable investigation upon the nature and properties of humus, which occupies more than one hundred pages in the fourth volume. The elucidation of the chemical nature of humus has been re- garded as an almost hopeless problem by the ordinary agricultural chemist. Berthelot has brought to bear upon the subject the methods and conceptions of modern organic chemistry, and his work has resulted in a considerable increase to our knowledge. Berthelot has carefully studied the composition and properties of the simple nitrogen-free humus obtained by boiling sugar with hydrochloric acid. It appears to be a mixture of a condensed anhydride and hydrate, the NO. 1562, VOL. 60] | simplest expression for the former being C,gH,,O,. It swells up in water, forming a colloid body. It absorbs | a considerable quantity of alkali from an aqueous solu- tion. One-third of the potash or soda thus absorbed is permanently retained in a practically insoluble condition after long washing with water. Placed in contact with ammonia an insoluble amido-compound is produced, from which ammonia is not recovered by boiling with magnesia. The oxidation of humus under the influence of light, and its more rapid oxidation in the presence of alkali are also studied. The heat relations of the prin- cipal reactions have also been ascertained. All this is fundamental work of very great importance, and throws much light upon the behaviour and functions of humus in a soil. The natural humus in soil is also studied, and the action of acids and alkalis upon it investigated. The gradual formation of ammonia when the nitro- genous humus of soils is boiled with weak acids, soluble nitrogenous compounds being simultaneously produced, is pointed out as in full agreement with the assumed amido nature of the humic matter. The humus of soils is, however, a very complex substance ; it may contain a very distinct amount of sulphur, and even phosphorus, in a state of organic combination. It will certainly be a novel fact for most agricultural chemists to hear that a soil may yield 0'183 per cent. of phosphoric acid when boiled with strong hydrochloric acid, 0°222 per cent. when the silica has been entirely removed by hydrofluoric acid and 0292 per cent. when the soil is burnt in oxygen gas and the products retained by sodium carbonate. The excess obtained by com- bustion in oxygen is regarded by Berthelot as represent- ing the phosphorus in organic combination. This part of the subject clearly requires much further investigation. Phosphorus, if present, is possibly a survival of the nuclein occurring both in the animal and vegetable kingdom. We take our next example from one of the less satis- factory of M. Berthelot’s investigations, in which the evidence brought forward seems quite insufficient to warrant the conclusions which he seeks to establish. He has determined the quantity of nitrates present in certain plants, and has conceived the idea that plants have the power of producing nitrates abundantly in their own tissues. This assumption, if proved, would clearly furnish an entirely new departure in vegetable physiology One would have thought that to establish such an hypothesis the plant would have been grown in a medium supplying no nitrates ; any appearing in the plant would then clearly be due to the work of the plant itself. M. Berthelot makes no such experiment. To establish his position, he grows the plant (borage or Amaranthus) in the open field, without any knowledge of the quantity of nitrates produced in the soil during the season of growth, and without taking into account the upward movement of subsoil water containing nitrates during the dry summer of his experiment. He is satisfied by ascertaining that on September 25 a square foot of soil contained only about 1/20 of the quantity of nitrate contained in the plant pulled up from it, and that a similar bulk of soil taken at the beginning of the season, from another part of the AA 542 NATORLE [OcTOBER 5, 1899 field, contained a similar quantity of nitrate to that found in the exhausted soil around the plant at the end of the season. ‘The next year he finds that the soil of the field, when deprived of vegetation, doubled its contents in nitrates between June 4 and “the end of the season” ; but this rate of increase was insufficient to account for the nitrates found in the crop the previous year / Finally, to prove that the plant contains a nitrifying agent, a single experiment is made by introducing a fragment of the stem of Amaranthus into a flask containing 300 grams of sterilised and exhausted soil. At the end of eleven weeks six milligrams of saltpetre were found in the soil. A blank experiment, made with soil only, was for some reason only continued for six weeks. Data such as these are quite insufficient to convince a critical reader. Our confidence in the investigation is not increased by reading that the growth of a single crop in the field diminished the nitrogen in the soil from 275 to 173 per cent., and the potash of the soil in the neighbourhood of the roots from *64 to °47 per cent. Nor by remarking that the same figures for nitrates in the soil are first quoted as kilograms, and are afterwards always spoken of as grams. The whole of the first volume is occupied with an account of investigations on the fixation of atmospheric nitrogen by soil and plants. M. Berthelot has been a pioneer in this branch of inquiry. The peculiar function of the organism forming the nodules on the roots of leguminous plants is now universally recognised. A similar case of symbiosis between a nitrogen-assimilating organism and certain algz is also well known. Not so well known is the isolation of a bacillus from the soil by Winogradsky, which when supplied with sugar, and protected from the action of oxygen, is capable of assimilating atmospheric nitrogen. This organism suc- ceeds in assimilating nitrogen from ordinary air when it is associated with azrobic organisms which appropriate the oxygen, and thus produce conditions suitable for the growth of the bacillus assimilating nitrogen. Both in the case of the reaction in the leguminous rootlets and algze, and in the case of the reaction 77 vitro, studied by Winogradsky, we have a clear in- dication of the source of the chemical energy which ac- complishes the difficult task of bringing nitrogen into a state of organic combination ; in every case we have carbohydrates abundantly present, and in Winogradsky’s experiments we have a demonstration that the quantity of sugar fermented is a measure of the quantity of gaseous nitrogen assimilated. With this principle before us we should suppose that a soil entirely destitute of vegetation could fix nitrogen only at the expense of its own organic matter; carbon would, in fact, be lost in the operation of fixing nitrogen. If, on the other hand, certain green algze or leguminous plants were present, fixation of nitrogen might be accom- panied by an actual gain of organic matter. According to Berthelot’s experiments, soils destitute of visible vegetation may gain large quantities of nitrogen when exposed to air. Even subsoils of argillaceous sand or clay, containing mere traces of carbon or nitrogen, are capable of gaining considerably in nitrogen when ex- posed to air. From an agricultural point of view, the quantities of nitrogen fixed are very considerable. Layers, NO. 1562, VOL. 60] 7 inches deep, of three surface soils from Meudon, fixed in 11 weeks from 70 lbs. to 130 lbs. of nitrogen per acre, quantities equivalent to 6-11 tons of farmyard manure. If this enrichment of soil by mere exposure to air is a fact, we shall be very anxious to know what are the pre- cise conditions and limitations of such a beneficial action. Scientific agriculturists will be loath to admit that the exposure of a soil uncovered by vegetation tends to its permanent enrichment ; the process of weathering tends, on the contrary, to the exhaustion of soil capital, and not to an increase of nitrogenous organic matter. Berthelot’s trials of various organisms yielded results of a similar favourable character. Out of seven organisms tried five produced an active fixation of nitrogen. The composition of the medium was apparently indifferent, for a mixture of certain bacilli from soil with kaolin de- termined an increase of 32 per cent. of the original nitrogen in one case, and an increase of 150 per cent. in another. Among the organisms fixing nitrogen, Berthelot includes the common mould Aspergillus niger. In the last section of this volume Berthelot describes experiments which lead him to the conclusion that the natural electrical conditions, both of soil and plant, aid in bringing about the fixation of nitrogen from the air. It is to be regretted that the large amount of work contained in these volumes is not of a more thorough and definite character, but we are very thankful that the investigations have been published. R. W. OUR BOOK SHELF. Bird Life in an Arctic Spring; the Diaries of Dan Meinertzhagen and R. P. Hornby. Edited by Mrs. G. Meinertzhagen. Pp. ili +150. Illustrated. (London: Porter, 1899.) A PATHETIC interest attaches to this volume, as being practically a memorial to a most promising and talented young ornithologist, whose life was unhappily cut short almost at the outset of his career. The late Mr. D. Meinertzhagen was essentially a lover of bird-life, and thus a naturalist in the very best sense of that somewhat abused word. But he was much more than this, being an artist of great talent, whose sketches and etchings of birds form some of the most beautiful delineations of feathered life it has been our fortune to see. In addition to those illustrating the text itself, nearly thirty of these talented sketches have been photographically reproduced as an appendix to the present volume, and serve not only to enhance the general interest of the latter, but likewise to convey an excellent idea of the artistic capacity of the autho of the journal which constitutes its main claim to attention. As we gather from the preface, the book is mainly intended for private circulation, and only a limited number of copies are offered to the general public. On the whole, the editor has exercised a wise discretion in endeavouring to preserve the journal of her son as much as possible in its original form, although it must be con- fessed that a little fuller supervision on the part of a trained ornithologist than has been permitted would have been advantageous in a few instances. The journal is divided into two portions, the first and longer by Mr. Meinertzhagen, and the second by his companion Mr. Hornby. The trip to Lapland, of which these form the chronicle, was undertaken in 1897 ; and the journal of the originator breathes out the enthusiasm of an ardent bird-lover. The two companions appear toihave visited spots to which few if any Englishmen OcToBER 5, 1899] NATURE 543 have penetrated since Wolley’s time; and in collecting eggs they suffered almost from evéarass des richesses on account of the numbers that were brought in by the natives. One of the objects of their desire was to obtain a clutch of Smew’s eggs, but it was not an easy matter to identify these without some of the down from the nest. they thought were the right eggs ; and their acumen was confirmed on arrival in England by the identification of the specimens from the down. A section of the volume is also devoted to an account of the magnificent collection of raptorial birds main- tained by the late author of the first journal at his father’s seat, Mottisfont Abbey, Romsey. This collection, which is stated to be one of the finest in England, is still main- tained ; and the account shows how it is possible to keep such splendid birds in perfect condition. Alto- gether, the bird-lover will find much to interest him in this charming little volume. Rem. Progressive Lessons in Science. By A. Abbott, M.A., and Arthur Key, M.A. Pp. xix + 320. (London: Blackie and Son, Ltd., 1899.) THIS book consists of two parts—the first, by Mr. Abbott, dealing with the non-metallic elements found in animal and vegetable substances ; the second, by Mr. Key, on the detection and distribution of the elements in animal, vegetable and mineral substances. The former part contains a course of experimental work in chemistry of a kind with which many text-books have made us familiar. All that need be said of it is that most of the experiments are suitable for performance in the laboratory by beginners in chemistry, and that the book will assist the progress of rational methods of science teaching. With regard to the second part, though the plan has something to commend it, the execution is open to criticism. Mr. T. G. Rooper, who generously endeavours to assist the volume by his introduction, remarks upon the idea to which we refer. “The most original feature in the book is the set of experiments which illustrate the composition of food-stuffs. Starting with a table of the chief consti- tuents of the blood, the author proves the presence of each by the use of an ingeniously-devised test. He then traces each constituent through animal life to the vege- table life on which animal life is supported, and thence to the soil from which the plant derives it, and finally to the rock, by the disintegration of which the soil is formed.” There are several grave objections to this method of procedure as it is here presented. Students are told the tests which have to be applied to detect different substances, hence the experiments are not in advance of the test-tube practice which is fast giving place to more intelligent practical instruction. Moreover, the object of the experiments is too complicated to be of real edu- cational value to beginners; and, finally, very few students have the time to do so much experimental work. Originality in text-books is a very commendable characteristic, but the authors should know that practic- ability is an even more important factor to consider. In its present form the book may be of service to a few teachers of domestic science and hygiene, but we do not think any other useful purpose will be served by its publication. De la Méthode dans la Psychologie des Sentiments. By F. Rauh. Pp. 305. (Paris: Félix Alcan, 1899.) THIs is a valuable monograph the merit of which is un- fortunately partly concealed by a singularly obscure and unattractive literary style. M. Rauh’s principal object is to enter a warning against the growing tendency of psychologists to neglect the adequate description of com- plicated facts, and to corrupt their science in its infancy by excessive reliance upon over-simple metaphysical and psychophysical theories. Psychology, as he well points out, possesses as yet no such simple and universal generalisation as that of the conservation of energy ; in NO. 1562, VOL. 60] At length they succeeded in obtaining what, the present state of the science any single theoretica generalisation is premature ; for the full description of the facts of mental life we need many points of view, each represented by a different tentative hypothesis. Thus the emotions, which form the immediate subject of the essay, may be studied as concomitants of physiological changes in the organism, as embodying a gvasz-judgment on the part of the organism as to what is beneficial or harmful, as manifestations of the “will to live,” or finally as special phenomena calling for independent description and classification. Each of these points of view throws light upon some characteristic of human emotions, and none of them can be neglected in a complete psychology of sentiment. In the course of the argument many one- sided theories, especially that of Prof. James as to the organic concomitants of emotion, receive really trenchant criticism. Like most French writers, M. Rauh is par- ticularly happy in what may be called “ psychological diagnosis”; his too rare descriptions of the various emotional “temperaments” are subtle and illuminating. On the other hand, he makes occasional slips which partly vitiate his reasoning. In his deductions from the supposed existence of special “ pain-conducting ” nerves, for instance, he forgets to allow for the possibility that what the nerve conducts is the special presentative element, the “racking,” “stabbing,” or “burning” sensation rather than the painfulness of it. Again, he scarcely lays enough stress on the fact that our emotional state at any moment depends, not on isolated sensations, but upon the total complex of our sensations at the moment. And, finally, to the present writer at least, the conception of ‘psychical forces,” of which M. Rauh makes great use, is exceedingly obscure. It is a pity that terminology, which has led to so many confusions, even in dynamics, should be needlessly transported into psychology. AS Eyl. Histoire Abrégée de l'Astronomte. Par Ernest Lebon. Pp. vii + 288. (Paris: Gauthier-Villars, 1899.) THIS book, as its title implies, is not intended as a com- plete history of the progress of astronomical science from the earliest day, but is devoted to rendering a brief account of the main steps in this progress, and at the same time giving us short biographical sketches of the chief workers in this branch of science. The subject is divided into three parts. The first deals with the ancient period which ends in the middle of the sixteenth cen- tury: only eighteen pages are devoted to this portion, so that the reader can rightly conclude that only a very general sketch has been attempted. The second or modern period, extending to the middle of the nine- teenth century, commences with the system of Copernicus, and ends with an account of the state of the science at the time of the death of the illustrious astronomer of the Kénigsberg Observatory, Friedrich-Wilhelm Bessel. The last, or contemporary, period is contained in 125 pages. M. Lebon divides this portion of the book into ten chapters, dealing in each with the progress made in separate branches of the subject. Thus we find first an account of the advance made in celestial mechanics, then the progress in observational astronomy, spectro- . scopy, geodesy, photography, &c. Each of these reviews is brought well up to date, and contains a good general survey of the progress made. A useful addition to the book will be found in the biographical and bibliographical dictionary which follows this last portion. Besides a small chart of the northern hemisphere, which apparently has little utility in such a book as this, the illustrations include a set of sixteen processed reproductions of por- traits of celebrated astronomers. Not only should astronomical readers find this book a welcome addition to their libraries, but those interested in the welfare of this, the oldest, of sciences, will peruse these pages with advantage. 544 LETTERS TO THE EDITOR. The Editor does not hold himself responsible for opinions ex- pressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for thts or any other part of NATURE. No notice ts taken of anonymous communications. | The Intake of Carbon Dioxide—a Correction. WILL you give me the opportunity of making the following correction in my Presidential Address to the Chemical Section of the British Association. I stated incidentally that Mr. F. F. Blackman, in his well- known experiments on the intake of carbon dioxide into the two sides of an assimilating leaf, employed air enriched with that gas to the extent of 4 per cent. and upwards. Mr. Blackman has pointed out to me that in the experiments in question he used air containing only from 1°8 to *33 per cent., and that since the publication of his earlier results he has still further reduced this amount. In fact he is of the opinion that his method is applicable to the measurement of the intake of carbon dioxide of even a much greater degree of dilation. The error was an inexcusable one on my part, but does net affect the main argument that the natural rate of intake cannot be directly deduced from experiments in which the carbon dioxide content of the air materially departs from the normal amount 0’03 per cent. Horace T. BRowN. 52 Nevern Square, Kensington, S.W., September. Geological Time. In his Presidential Address to Section C at Dover, Sir A. Geikie has offered a bold challenge to Lord Kelvin and those who agree with him by calling upon them to give due weight to geological phenomena in forming an estimate of geological time. Permit me to say what I think about it. It seems to me probable that, when the grand idea of the universal dissipation of energy had occurred to Lord Kelvin, he saw that the principle must be applicable to the earth, and that, if the law of conduction of heat could be used, he might from it obtain an estimate of the world’s age. He then instituted his important experiments to determine the conductivity of rocks zm s?tw, and found the value 400 (more or less), the units being a foot a year, and a degree Fahr. But it was necessary, for his calculation to succeed, that he should assume the earth to be solid. If I do not misjudge him, I think he then sought for arguments to prove this point. Now, I cannot but think that the proofs of solidity on which physicists rely are by no means convincing ; and if the earth is not solid, Lord Kelvin’s esti- mates are without foundation. Moreover, it is not sufficient that the earth should be solid at the present, to which these proofs refer, but it needs to have been so from the beginning of the time to which his estimates go back. Prof. G. Darwin, in his book on the tides (p. 237), has done me the honour of referring to my ‘‘ Physics of the Earth’s Crust ” as if I am an arch-heretic on this question of solidity. Whether my arguments are beneath notice, or whether there 1s a difficulty in answering them, I do not know; but they have never been refuted, while they are held to be of decided force by some geologists, and among these by the Indian Geological Survey. Harlton, Cambridge, September 25. O. FISHER. The Terrestrial Gegenschein. I po not know whether the phenomenon I am about to describe has ever been noticed. The circumstances under which it is noticeable must occur rarely. They are these :— I spent some time of the summer of 1898 on an isolated mountain peak, surrounded by lower mountains whose sides were densely wooded. The result was that near the time of sunset the shadow of my own mountain peak was visible on a mountain side which might have been three or four miles distant. One evening I amused myself by watching the shadow of the peak as the sun was descending. My attention was attracted by an illumination in the direction opposite the sun so strikingly resembling the astronomical gegenschein, that at the first glance I saw in it an explanation of the latter. It consisted of a somewhat bright glow, which might be a degree or two in diameter, but which shaded off by such imperceptible gradations that a definite extent could not be assigned. A NO. 1562, VOL. 60] NALORL [OcToBER 5, 1899 little study, however, showed an explanation. As I have said, the mountain on which the glow was seen was densely wooded. In such a case the shadows of those leaves and branches which the sun’s rays first reached fell upon the interior foliage and obscured it. But an observer looking from the exact direction of the sun will see through the foliage as far as the sun’s rays extend. In other words, the visible surface on «which he is looking will be entirely illuminated by the sun’s rays, whether this surface is formed of the outer strata of foliage or of a strata ever so far inside, which can be seen only through the crevices in the outer stratum. The shaded interior will be entirely invisible to him. But if his point of view is in a direction ever so little oblique, he will see only the outer foliage illuminated, while more or less of the interior foliage which he sees will be in the shadow. Thus the region exactly opposite the sun will be seen in its full brilliancy, while the neighbouring region will be a mixture of light and darkness. At a distance of several miles this compound of light and darkness will be fused into a single half-shade, strongly contrasting with the full brilliant light of the opposite point. It is clear enough that we cannot have such a state of things as this in the case of the astronomical phenomena. Yet the phenomenon seems to be of sufficient interest to warrant its being placed on record. S. NEWcoMB. The Cause of Undercurrents. In NaTureE of August 3, p. 316, is given a letter from Rear- Admiral Sir William Wharton, in which he states that he is diametrically opposed to my opinion about the double currents in the Straits. He says that ‘* Admiral Makaroff considers that difference of density of the water is the primary, and, indeed I gather he thinks, the only cause of these opposing currents ; but he brings no evidence beyond theoretical considerations in support of his belief” ; further, in his letter, Admiral Wharton refers particularly to the double current of the Bosporus, of which I spoke in my lecture at the Royal Society of Edinburgh. I cannot leave unnoticed remarks from so distinguished a hydrographer, who, during his long work, has contributed so much to the advance of science. My researches about the Bosporus are published only in Russian, in a book named “On exchange of water between Black Sea and Mediter- ranean” (St. Petersburg, 1885). Should Admiral Wharton know my language, he would easily come to the conclusion that my opinion about double currents in the Bosporus are based upon the observations made in 1881 and 1882. I then invented an instrument for measuring the current at different depths, and gave the name of ‘‘fluctometer”’ to it. The instrument consists of a propeller revolving on a horizontal spindle. A bell is attached to the propeller, and at every revolution of the propeller it strikes twice. As water is a very good conductor of sound, the number of revolutions could be counted through the bottom of the ship (provided the ship is not sheeted with wood) at all depths to which the instrument was lowered (40 fathoms), I used to anchor in the middle of the Bosporus for a couple of days at a time, and make a series of observations every two hours. In order to obtain more detailed data, I used to take the samples of water from the same depth to which the fluctometer was lowered. Twice I used to go along the Bosporus from the Black Sea to the Marmora Sea in order to learn in what depth is the limit of two currents. In volume xxii. of the Proceedings of the Royal Society of Edinburgh, Plate I. shows a position of the limit of two currents, mean velocity of both currents, and specific gravity of water. In Plate II. is given a sketch of my ‘‘ fluctometer.” I am sorry that the limits of this paper do not allow me to give particulars of my observations, but I believe some of my deductions, worked out from direct observations, would be interesting to English readers. Mean velocity of the upper current, 3} feet per second. It varies from © to 10 feet per second in certain places. Velocity of the upper current diminishes with every fathom of depth. : Limit between two currents close to the Marmora Sea is at 11 fathoms. It gradually goes down to 27 fathoms close to the Black Sea. Limit between two currents is influenced by winds and by barometrical pressure, but not very much. Lower current has close resemblance with the river. Its velocity does not vary very much. We never found anywhere OcToBER 5, 1899 | lower current less than 1°84 and more than 3°22 feet per second. Mean velocity of the under current was 2°32. The upper current does not everywhere occupy the full breadth of the strait. It flows in some places under the north coast of the strait, and in other places under the south coast. Lower current also does not flow over the whole breadth, and occupies a certain part of the bed of the strait. In my book I give a chart of the Bosporus, where I show direction of the upper and lowercurrents. A glance at that chart will show that there are places where both currents can be found, and there are places where the instrument will show the existence of only one of ‘them, and in some places the explorer will not find either upper direct current or under current. Difference of level of Black and Marmora Seas, calculated from difference of specific gravity of water, is 1 foot 5 inches. 1775 Mean specific gravity of water (sizs) entering from the Black Sea into the Bosporus is 1‘orgo. Mean specific gravity of water entering from the Marmora into the Bosporus is 1'0283. By upper current pass 370,000 cubic feet per second. By lower current pass 200,000 feet persecond. Difference between these two figures being 170,000 feet per second is due to the excess of fresh water in the Black Sea. I hope that after reading these figures and deductions Admiral Wharton will change his opinion, and come to the conclusion that my idea about double current in the Bosporus is based, not only on theoretical considerations, but also upon direct measurement. Admira Wharton expresses also his opinion about double current of the strait of Bab-el-mandeb, and says that “‘ there are none of the differences of specific gravity.” Imay be permitted to refer to my other book, ‘‘ Le Vitiaz et l’Ocean Pacifique,” where I give (p. 136, plate xxvii.) specific gravity of the strait of Bab-el-Mandeb measured by myself. Examination of figures given there by me shows that there is a difference of specific gravity which produces double current in that strait. Nobody can deny that the wind has a great influence upon the movement of surface water; but I hope that Admiral Wharton will agree with me that differences of specific gravity has also some influence upon the circulation of water in the seas generally and in the straits particularly. S. MAKAROFF. Lrmack, Newcastle-upon-Tyne, September 23. Movement of Sea-Gulls with a Coming Change of Weather. THE suggestion that sea-gulls may have some meteorological sense would be best tested by inquiry as to whether there was, at the time of their westward flights, observed by your recent correspondents, any other possible motive for their journeys ; and particularly what food was available in the Channel at the time. Neither of your correspondents needs to be told that every sea-gull is a semaphore to every other sea-gull in sight of him, nor that one gull ** working on”’ fish will presently be surrounded by others from all sides. In clear, fine weather the news of abundant sprats would be passed. along the Channel in this way, faster than by military signallers, and answered by a concentration of gulls much speedier than any possible to troops. Moreover these birds, and vultures, as I know from repeated observation, do not merely fo//ow each other round the head- lands. If a gullina bay sees another gull hurrying from the offing into the next bay, he does not fly round the headland between, but rises over it, well knowing that from the upper air he will see whatever hurried the outer gull. As he does so his motions will be observed, and probably acted on by others further within the first bay ; and if food be failing in the Thames, and abundant off the Wight, there will be plenty of gulls flying across Kent, and some across even Surrey. Here in Chelsea I seldom see large gulls on the river. But it is a common enough thing to see them flying high overhead to the south- westward. Westerly and south-westerly gales are so common in the Channel that neither beast nor bird can make any movement without a good off-chance of finding one on his way. It has to be remembered that most of our migratory sea fish are apt to run up Channel in the warm half of the year, so that the message, “* Plenty of fish on the surface,” is probably most often passed from west to east. NO. 1562, VOL. 60] ING AMI OD I'S 945 We shall, I think, need a good many simultaneous observ- ations at various points and of various matters before we make it even probable that sea-gulls can foretell a south-west wind, and will then go to meet it. They cannot eat it ; and, if strong, it will give them little leave to eat anything else ; so the motive is not apparent. W. F. SINCLAIR. 102 Cheyne Walk, Chelsea, S. W., September 22. On the Use of the Fahrenheit Scale for Observations on Sea Temperatures. In addition to the Fahrenheit scale being so much more practical for observation in meteorology than the Celsius, allow me to point out that in observations for ocean temperature it is even more so, and especially when we come to deal with ob- servations taken in the polar regions. Here with the Fahrenheit scale we have never to deal with a minus reading at all; whereas with the Celsius scale it is a constant change from plus to minus and minus to plus. This introduces a source of very serious error both in observation and calculation, besides adding to the work, and therefore the cost of working up results. The boon of never having to think of a minus in such work is not to be lost sight of for the sake of fashion. As one who has taken part in extensive observation and calculation work at Ben Nevis Observatory, on board ship, and in connection with the Scottish Fishery Board, I would also urge the use of the Fahrenheit scale for meteorological observations on the same grounds as Mr. J. Y. Buchanan and Mr. H. Helm Clayton. Joppa, Edinburgh, September 25. | WILLIAM S. BRUCE. Cave Shelters and the Aborigines of Tasmania. I HAVE just received news from Mr. J. B. Walker, ot Hobart, of the discovery of some interesting relics of the aborigines of Tasmania. Mr. Walker accompanied Mr, R. M. Johnston, the Government Geologist, on an expedition in search of some remains of Tasmanians, and the party were rewarded by finding a hitherto unknown so-called quarry where the natives manufactured some stone implements, also a cave which showed considerable evidence of having been used by the aborigines, as well as a tree notched by them for climbing purposes. The sandstone cave or rock shelter i situated in Hutton Park, near Lovely Banks. The quarry is situated at Coal Hill, two miles north of Melton Mowbray, about 40 miles N.N.W. of Hobart, and 1100 feet above the sea-level. The discovery of this quarry makes the tenth known quarry used by the aborigines, and the first mention of their use of cave or rock shelters. H. Line Roru. Halifax (Yorks.), September 27. The Darjeeling Disaster. UNUSUALLY large seismograms were obtained in the Isle of Wight on September 3, 10, 17, 20 and 23. The first three: refer to disturbances originating in Alaska. The fourth refers to disasters in Asia Minor, and the last to an earthquake having an origin as distant as Japan. Since the 23rd in the Isle of Wight, and I believe also at Kew, not the slightest movement has been recorded. The inference is that the great earthquakes reported as having taken place at Darjeeling on the night of September 25-26 are at the most small and local, and are not likely to have been recorded outside the Indian Peninsula. It is extremely likely that the tremors noticed in Darjeeling were due to iandslides, and seismic phenomena were entirely absent. J. MILNE. Shide Hill House, Shide, Newport, Isle of Wight, September 27. Lectures at the Royal Victoria Hall. I SEE in your issue of September 21 (p. 513) the statement that I am to lecture at the Royal Victoria Hall on ‘ Photo- graphs taken in the dark.” I beg to say that the title I gave for my lecture was ‘‘ Pictures taken on a photographic plate in the dark.” I suppose the authorities at the Hall consider the titles identical. I do not. W. J. RUSSELL. St. Ives, Ringwood, Hants, September 26. 546 NATURE [OcToBER 5, 1899 Vole. J THINK NaTuRE should take note of a short article by Prof. Skeat in the number of Motes and Queries for September 16, wherein he points out that vo/e is corrupt Norwegian for field, and that therefore a water-vole is a water-field, a field- vole a field-field, and a bank-vole a bank-field. Exeter. JAMES DALLAS. THE INVESTIGATION OF THE MALARIAL PARASITE. ENDING the arrival here of Major Ross and part of the Malaria Expedition connected with the Liverpool School of Tropical Diseases, which is expected about October 7, we may, from information already to hand, forecast some points in his report without in any way detracting from the interest with which it will be received. In the issue of this journal for September 7 we recorded the fact that a species of Anopheles was found to be con- cerned in the transference of allthe forms of malaria. In the barracks of Wilberforce, a suburb of Freetown, Sierra Leone, out of four hundred men there was a daily average of forty ill in hospital with all three forms of malaria. The place seems to have been infested with mosquitoes, but only the genus Anopheles was found, and of those examined one-third were found to contain zygotoblasts. In searching for the haunts of the Anopheles larvee the members of the expedition found them chiefly in small stagnant pools in which green algae were growing. The larve appear to live upon this, for larva hatched from eggs did not grow unless they were given some of the alge to feed upon. They infer that the conditions under which alge will grow, namely, in stagnant puddles, are the same as those under which Anopheles larve will hatch out and thrive ; the larvee of Culex were found in every re- ceptacle for stagnant water, even in old sardine tins. Stagnant puddles are only found during the rains on low- lying ground, and near a stream or spring, from which they can be replenished in the dry season. So far, only one experiment on the action of kerosene oil on larve has been reported ; one drachm of the oil was poured on the surface of a pool of water of about a square yard in area, and all the Anopheles larve it contained were found dead after six hours. Ross considers the Anopheles to be the genus con- cerned in propagating malaria, and seems to rely on being able to exterminate them from a locality to free it from the disease. Koch (Erster Berichtiiber die Thitigkett der Malaria Expedition, April 25 bis August 1, 1899) found Culex pipiens to be concerned in propagating malaria in Tuscany, but to a lesser extent than the Anopheles. The German Commission find that the parasite requires a temperature of 80° F. to develop in the mosquito, and it is only found in these insects during the summer months. At the commencement of the hot weather the mosquito draws the parasite with the blood from a patient who has a relapse. Human beings with the parasite in their blood they consider to be the connecting link during the nine months of the year when the temperature does not allow of the parasite developing in the mosquito ; they think relapses can be stopped by the use of quinine ; so by this means it would become possible to stamp out the disease. It is evident we want a large series of observations made in different parts of the world, for, if the genus Culex can propagate the disease, it would be almost im- possible to exterminate these if they breed wherever water lies. On the other hand, should relapses of fever be prevented by a proper use of quinine, malaria would not be stamped out in countries where the temperature is sufficiently high all the year round to allow the parasite to develop in the mosquito. NO. 1562, VOL. 60] MR. PERGYVOS PIL CHER. ANY of our readers who were acquainted with Mr. Percy S. Pilcher, and others who have only heard of him through his great enterprise and keenness in con- structing and using aérial machines, will be very sorry to: hear that his accident on Saturday last has proved fatal, and that he died at 2.40 on Monday morning. Mr. Pilcher, during the last few years, had been making a considerable number of experiments with the object of constructing a soaring machine which would propel itself. The writer of this note was present at one of his trials in August 1897, at the time when he was at work in design- ing a small light engine for propelling his machine, and communicated to this journal an account (with illus- trations from photographs) of his experiments on that occasion (NATURE, vol. lvi. p. 344). Like his forerunner Otto Lilienthal, Mr: Pilcher has. come to the same sad end, and now his name must be added to that already long list of pioneers in aérial Navigation. The experiments causing the fatality took place on Saturday last at Stanford Hall, the seat of Lord Braye, near Market Harborough. We gather from the 7Zzmes that after several in- effectual attempts to start, a signal was given about twenty minutes past four, and Mr. Pilcher rose slowly in the machine until he had travelled about 150 yards, and had risen to a height of about 50 feet or 60 feet. Then a sharp gust of wind came and the tail of the apparatus snapped. Instantly the machine turned completely over and fell to the earth with a terrible thud, Mr. Pilcher being underneath the wreckage. His devoted sister was one of the first to reach the scene of the accident. Mr. Adrian Verney-Cave, Mr. Everard Fielding, and Dr. Stuart, all friends and companions of Mr. Pilcher, re- moved him from the machine and found that he was unconscious. Raising his left leg it was discovered that it was fractured above the knee. Mr. Pilcher was carried to his room in the house, and Dr. Stuart and Dr. Nash carefully examined him, another surgeon being summoned by telegraph from Rugby. Way: Sis NOTES. ' PROF, SIMON NEwWcomB has been elected president of the recently established Astronomical and Astrophysical Society of America, The secretary is Prof. G. C. Comstock. THE seventh International Geographical Congress began a series of successful meetings on Wednesday, September 27, at Berlin. Papers have been read by, among others, the Prince of Monaco, on his Greenland Deep-sea Expedition, and Dr. Nansen, on ‘‘ The Hydrography of the Polar Sea.” At one of the sittings of the Congress a telegram was read from Mr. H. J. Mackinder, the Reader of Geography at Oxford, announcing that he had succeeded in reaching the summit of the hitherto unscaled Mount Kenia in British East Africa, and that some fifteen glaciers were found upon the mountain. It will be remembered that Mr. Mackinder left England in June last in charge of an exploring expedition. A Buoy bearing the inscription ‘‘ Andrée’s Polar Expedition,” found on the north side of King Charles Island, north-east of Spitsbergen, So° latitude and 25° east of Greenwich, on September 11, has been brought to Stockholm and there opened in the presence of several experts and Ministers. It was found to be the so-called ‘‘ North Pole buoy ” which the explorer was to have dropped when passing the North Pole. So far as the examination extended no message from the explorer was OctosER 5, 1899] NATURE 547 revealed, Prof. Nathorst declared that the buoy could not have been carried from the Pole to King Charles Island, and Captain Svedenborg was of opinion that it had been thrown out empty. A search is, it is stated, to be made next year at King Charles Island. A MARBLE bust of Prof. Emil Du Bois Reymond has been presented to the Physiological Institute of the University of Berlin by the professor’s widow. THE new Paris Institute of Biological Chemistry, facing the Pasteur Institute, towards the erection and endowment of which Baroness Hirsch gave 80,000/., is now, so far as the exterior is concerned, completed. Pror. R. BuRCKHARDT, of Basle, and Prof. V. Uhlig, of Prague, have been elected members of the Academy of Sciences of Halle. Tue death is announced, at the age of forty-five, of Dr. Kowalowsky, professor of hygiene in the University of Warsaw, and of Canon Carnoy, professor of the natural sciences at the University of Louvain. In connection with the Glasgow Lecture Association a special science lecture will be given to school children during the Christmas holidays by Prof. McKendrick, F.R.S. PRor. GEORG STEINDOREF, the director of the Aegyptolo- gische Sammlung at Leipzig, has, it is stated, obtained leave of absence for six months to enable him to undertake a scientific journey to Africa. Dr. L. A. Bauegr, of the U.S. Coast and Geodetic Survey, is at present in Europe for the purpose of inspecting various magnetic observatories and the comparison of the Coast and Geodetic Survey instruments with observatory standards. THE announcement is made that Mr. W. H. Twelvetrees has been appointed geologist to the Government of Tasmania. During recent years Mr. Twelvetrees has devoted conside rable attention to the geological formation of Tasmania, with special reference to mining operations, and has been a frequent con- tributor of papers to the Australian Institute of Mining Engineers and to the Royal Society of Tasmania. THE Corporation of Glasgow has just appointed Dr. R. M. Buchanan bacteriologist to the city. He will devote the whole of his time to the duties of the office, and a laboratory has been assigned to him in the Sanitary Chambers. Ir is announced in the Péoreer Maz! that Mr. Douglas Fresh- field has arrived at Darjeeling, accompanied by two Swiss guides, intent on exploring the great snowfields of Kinchiniunga. THE tenth International Congress of Hygiene and Demo- graphy will be held in Paris from August 9 to 17, 1900. THE second International Congress on Hypnotism will be held in Paris from August 12 to 16, 1900, under the presidency of Dr. Jules Voisin. The questions proposed for discussion are : (1) The formation of a vocabulary concerning the terminology of hypnotism and the phenomena connected therewith ; (2) the re- lations of hypnotism with hysteria; (3) the application of hypnotism to general therapeutics; (4) the indications for hypnotism and suggestions in the treatment of mental disease and alcoholism; (5) the application of hypnotism to general | pedagogy and mental orthopedics ; (6) the value of hypnotism as a means of psychological investigation ; (7) hypnotism in relation to the (French) law of November 30, 1892, as to the practice of medicine ; (8} suggestion and hypnotism in relation to jurisprudence; (9) special responsibilities arising from the practice of experimental hypnotism. NO. 1562, VOL. 60] IN compliance with the request made by Russian men o1 science to the Russian imperial authorities, the scientific ex- ploration of the coast-line of the Pacific in the Far East is to be undertaken. It has been arranged that a distinguished zoologist and member of the Imperial Russian Geographical Society shall undertake the exploration at the cost of the Society, in conjunction with the Ministry of Agriculture. The expedition intends to make investigations with a view to classifying the marine fauna and flora on the coast of the Russian territory, and the conditions of zoological life will also be investigated upon the Liao-Tong peninsula, and in the adjacent regions of Manchuria and Korea. The period for these investigations has been fixed at two years, and the cost of the expedition is esti- mated at 12,000 roubles. The Geographical Society has pro- mised to make a grant of 7500 roubles towards this sum, and the Ministry of Agriculture and Imperial Domains will con- tribute the remaining 4500 roubles. The Ministry of Agriculture has been led to take a part in this expedition in the expectation that its results will be of great service in developing the coast industries of the Amur and the Island of Saghalien, and also in the districts which have been acquired lately by the Russian Government. The Geographical Society also entertains great hopes of the successful results of this expedition, in view of the fact that the previous expeditions sent by it to investigate the Black, Azov, and Marmora seas were particularly successful. The expedition to the Far East will work in conjunction with the Society for Exploring the Amur Territory, and intends to establish at Vladivostock a zoological station for studying the marine fauna of the district. Science states that the late Richard B. Westbrook, of Phila- delphia, has made a bequest of 10,000 dollars, taking effect on the death of his widow, to the Wagner Institute of Science. The sum is to be used as an endowment of a special lectureship to ‘‘ secure the full and fearless discussion by the most learned and distinguished men and women in our own and other countries of mooted or disputed questions in science, and especially the theories of evolution.” A YEAK ago Cornell University secured 30,000 acres of woodland in the Adirondack Mountains for the exclusive use of the University’s forestry department. The land has been divided into a number of sections, and several seed beds have been laid out in which there has been planted over a million small trees of different varieties. The students of forestry will study the theory of the subject from October to April, and from then until Commencement they will study the practical side of forestry. Cornell University is, according to the Sczentific American, the only college in the United States which has a forestry department. THE Sczentific American states that the men of science who have been investigating the Wyoming fossil beds are having remarkable success, and a large number of boxes containing fossil remains have been sent to the State University, and the work of restoration will soon be begun under the direction of Prof. Wilbur C. Knight. DuRING this summer a number of field parties in connection with the United States Fish Commission have been engaged, in various States, in ichthyological and other investigations. A camping party under the direction of Dr. Charles H. Gilbert has, says Scéence, systematically examined the coastal streams of Oregon, with reference to their fish fauna; the eastern tribu- taries of the Sacramento have been visited by Mr. C. Rutter ; a comprehensive study of the biological and physical features of the Wabash basin has been begun under the direction of Prof. B. W. Evermann; a party in charge of Mr. W. P. Hay has explored: the Monongahela basin in West Virginia; Dr, P. H. 548 NATORE [OcTOBER 5. 1899 Kirsch has been collecting and studying the fishes o: the San Pedro River, Arizona; in connection with the biological survey of Lake Erie, Prof. J. Reighard and assistants have cruised along the northern and southern shores of the lake in a special steamer; Dr. H. M. Smith has visited Seneca Lake, N.Y., for the purpose of determining the character of its fish fauna ; a study of the variations of the mackerel of the east coast has been conducted by Mr. M. C. Marsh, and in the interesting Sebago and Cobbosseecontee lake regions of Maine, Dr. W. C. Kendall has made some special investigations regarding salmon and other fishes. THE return of the schooner /u/za EZ. Whalen, after an absence of nearly a year, is announced in Scéence. The vessel was sent out by Stanford University on a scientific cruise among the Galapagos Islands, &c., and carried members of a scientific expedition under the direction of R. E. Snodgrass, entomo- logist, and E. Heller, zoologist. A large collection of speci- mens, including birds, mammals, invertebrates, and fish, was obtained. On board the vessel were eighteen live land tortoises taken from Duncan and Albemarle Islands, some of them weighing four hundred pounds ; also 220 fur sealskins and 2300 skins of hair seals. A REMARKABLE demonstration of the success of inoculation against the plague is to be found in the statement recently made to the Indian Imperial Research Labor- atory by Dr. Chinoy, the medical officer of the Southern Mahratta Railway at Hubli. In Hubli itself 4961 persons were inocu- lated once, 7840 persons twice, and 1346 persons thrice (these having been twice inoculated last year), or a grand total of 14,147. Inthe district 1849 persons were inoculated once, and 1967 twice, or alto- gether in Hubli and the district a total of 17,963 persons. In the words of Dr. Chinoy: ‘‘ There are about 1000 people living in the railway chawl, Hubli, which was seriously infected last year. A// them are tnoculated, and I am glad to be able to state that ot a single case of Plague has occurred amongst them since plague broke out in the town, although they freely move about and mix with people in the town, where plague is in- creasing daily.” THE report of the Imperial Bacteri- ologist at Calcutta for 1898-99 states that a considerable quantity of mallein and tuber- culin are being manufactured in the laboratory for veterinary use. The hope is expressed that arrangements may be made for dairy and other cattle to be tested with tuberculin, so as to ascertain the extent of tuberculosis amongst cattle in India. Attention has been given to the further investigation of ‘‘ surra,”” and the report says it is more than ever probable that this disease is identical with the South African tsetse-fly. THE Vienna correspondent of the 7zes reports some experi- ments in a new system of telegraphy made in Budapest and Berlin on Friday last. These are alleged to have given the extraordinary result of a transmission of no fewer than 220 words in ten seconds without prejudicing the clearness of the message. According to the reports from Budapest, the impression made upon the technical experts who had an opportunity of following the trial was favourable. A perforated roll of paper, similar to that at present in use, is employed for the despatch of the message, which is made visible and fixed photographically at NO. 1562, VOL. 60] the receiving station. Instead of the dashes and dots of the Morse alphabet there are rising and falling strokes starting from ahorizontalline. The receiver consists of a telephone fitted with a small concave mirror, upon which are reflected, in the form of streaks of light, the impulses marked on the membrane. By an ingenious arrangement, recalling in some respects that of the cinematograph, the streaks of light reflected upon the mirror are reproduced upon a roll of sensitised paper, thus giving a narrow oblong picture, which in the present stage of the invention is developed and fixed like any ordinary photograph. THE fumigation of trees sor the destruction or insect pests has for some time been extensively used in California and other parts of the United States. The process will probably soon come into use in New South Wales, for Mr. W. J. Allen describes in the Agrzcultural Gazette of the Colony some very successful experiments in spraying and fumigating for red and other scales on orange trees. The tree to be treated is com- pletely covered with a tent, such as is shown in the accompany- ing illustration, and is subjected for nearly an hour to the fumes of hydrocyanic acid, produced by the combination of sulphuric acid and potassium cyanide. The number of men generally employed in a fumigating gang is four or five, accord- ing to the size of the trees. One man introduces the chemicals, another looks out for the generator and measures the acid, and Placing tent over tree to be fumigated. two or three handle the tents. Such a gang can handle from thirty to forty medium-sized tents, and cover four to six acres of orchard in a night. Fumigation is to be preferred above spraying, because the trees are not in any way damaged by the fumes, except in the case of a few of the tender leaves, while the solution used in the sprays must to a certain extent close the pores of the tree and slightly weaken it. ACCORDING to the Avgéneer, the signalling on the whole oz the Pennsylvania Railroad system is now operated electrically. When a train passes a signal bridge it closes an electric circuit, which moves a signal semaphore to the ‘‘danger” position, When the train passes beyond the next bridge a circuit is opened, and the signal indicates that the block from which the train has just passed is clear. Finally, when the train passes beyond the third bridge, another signal arm on the same post drops, showing the driver of an approaching train that there is nothing on the next two blocks ahead. OcToBER 5, 1899] NATURE a) THE connection between fleas and the permanency, or other- wise, of continents might not at first sight be very apparent, but, nevertheless, some important evidence on the latter point is afforded in a paper by the Hon. N. C. Rothschild published in Novitates Zoologicae for December last. In this contribution the author, who is making fleas his special study, describes a new species of those insects on the evidence of a single specimen from Argentina, which is believed to take up its abode ona rat. Now this Argentine flea, which is remarkable on account of the helmet-like shield covering the head, is provisionally assigned to a genus (Stephanocircus) hitherto represented by a single Australian species infesting the spotted dasyure (Dasyurus maculatus). And we presume it may be taken for granted that, whether or no they are rightly regarded as congeneric, the two species are evidently very closely allied. Now this being so, it is difficult to see how they reached their respective habitats except by means of a direct land connection between Australia and South America ; and they accordingly serve to confirm the evidence afforded by the occurrence of the chelonian genus Miolania in both areas, to which attention has been recently drawn in these columns. THE discovery of a new generic type o: marine gastropod, represented by a species whose shell is over six inches in length, is such a rare event, that Mr. G. B. Sowerby’s description of Neptuneopsis gilchristé, from the Cape seas, demands a brief notice. In general form the shell (which sis described in the publications of the Cape Department of Agriculture for 1898) is so like some of the Buccinidae, such as Neptaunea (Chrysodomis) that, were it not for its curiously swollen apex, it might be re- ferred tothe genus mentioned. On the other hand, the tricuspid tooth-ribbon, or radula, is of the characteristic volute type ; and Mr. Sowerby consequently infers that the new genus should be placed in or near the Vole¢cdae. If included therein, it will represent an interesting annectant, and therefore gener- alised type. The generic name selected scarcely seems to us a happy one. THE close study of the smaller mammals of Europe on the lines followed by the American naturalists for those of their own country is gradually bringing to light the existence of numerous local races of species hitherto quite unsuspected. A remark- able instance of this is Mr. Barrett Hamilton’s recognition of two new forms of mice from St. Kilda, which are described in the June number of the Proc. Zool. Soc. The first of these (Mus hirtensis) is nearly allied to the wood mouse (JZ. sy/vat- tcus); while the second (JZ. muralzs) is as closely related to the common house mouse. The former the author regards as indigenous to St. Kilda since the period when that island was connected with the mainland; while the latter he considers to have been derived from individuals of JZ. musculus, introduced by human agency not more than a few hundred years ago. Yet both differ from their mainland prototypes to the same degree ; and thus indicate the different inherent variability of different species. The variation displayed by AZ. muralis is probably in the direction of the wild ancestor of AZ, muscudus. In the Jndian Meteorological Memoirs, vol. vi. part v., Mr. Eliot contributes a very important discussion of the air move- ment at Simla and in the Western Himalayas, deduced from anemometric observations recorded at Simla during four years ending August 1896. Some fifty years ago Sir Richard Strachey made a lengthened series of observations, chiefly in Kumaon, and in his description of the diurnal variation of the wind he considered the most important feature of the air movement in the Western Himalayas to be the up and down valley winds. Mr. Eliot’s discussion entirely confirms this view. He states that the examination of the wind data from every point of view shows that the most important and unique feature NO. 1562, VOL. 60] of the air movement is the alternating currents between the hills and plains. He states that it is a permanent feature, independent of the change of seasons, and also of the air movement in the plains of Northern India, and is due to the changes of pressure vertically produced by the unequal expansion and contraction of the lower and middle strata of the atmosphere over the plains of Upper India and the Western Himalayan mountain zone. THE U.S. Monthly Weather Review for June contains par- ticulars of the increased usefulness of the Canadian Weather Service. For the year 1896 (the last published) the Report consists of two large quarto volumes, instead of one octavo volume published a year or two previously. During that year there were more than three hundred stations of observation of various classes. At the chief stations (eight in number), the telegraphic reporting stations, and a few of the special stations, the observers are paid, but the great bulk of observers are volunteers. There are thirty telegraphic stations, whose reports are received in Toronto before 9.30 a.m., and which, combined with fifty-four reports received by exchange from the United States, enable the director at Toronto, Prof. Stupart, to issue daily weather maps and forecasts similar to those published by other meteorological offices. The second volume is wholly taken up with details and results of the observations made at the eight chief stations. For each of these the Report gives for every hour and day the complete record of all the principal meteorological elements, in a form closely corresponding to that recommended for international meteorological publication of detailed observations. Prof. Cleveland Abbe’s comment upon the work is that it is a noble contribution of data needed for the study of climatology inits relation to every matter that interests. civilised humanity. AN investigation of the emission and absorption of platinum- black and soot, and their dependency on the thickness of the layer employed, forms the subject of a paper by F. Kurlbaum in Wiedemann’s Annalen (67). It would appear that both sub- stances closely approach a black body in their behaviour towards. waves of the length emitted by a black body at a temperature of 100°. For shorter waves the power of absorption increases. Both platinum-black and soot satisfy the Stefan-Boltzmann law when a sufficiently thick layer exists at high temperatures 5 and any deviations from this law are due to the radiating surface, or the bolometer being too thinly coated. Several further results of interest are found, and the author considers that for several reasons platinum-black is better than soot in all experi- ments. In the Zyransactions of the Institution o. Mining Engineers, M. A. Rateau, Professor at the School of Mines, St. Etienne, describes experimental investigations on the theory of the Pitot tube and Woltmann mill, which are employed by engineers in gauging the rate of flow of air and water. Although the Pitot tube and mill and fan anemometers measure accurately the velocity of currents when these currents are uniform, they give, under opposite conditions which usually prevail, indications of the mean velocity which are always exaggerated, and are the more exaggerated the more marked the irregularity of the current itself. M. Rateau finds that the equation v=a+éx + c/v which holds for low velocities in connection with such meters should, for velocities unrestricted in magnitude, be written in the form 62 =v —- c/v — f(v)/v, where /(v) is a function of the resistance of the fluid with regard to which our knowledge is still somewhat deficient. In a note added later attention is drawn by the author to subsequent experiments by Mr. Epper, bearing on the same subject. As there are insufficient data on the normal relations of voluntary movement to consciousness, Dr. R. S. Woodworth 550 NATURE [OcToBER 5, 1899 ‘has set himself to this study, and his results are published as a monograph—‘‘ The Accuracy of Voluntary Movement ”—in The Psychological Review (vol. iii. 1899). The following are ‘some of his conclusions ; When the eyes are used, the accuracy of a movement diminishes as the speed increases; but it does not vary so much when the eyes are not used; the right hand is slightly more accurate than the left. When the interval between successive movements is kept constant and the speed of the motion alone varied, the accuracy diminishes rapidly as the speed increases, the accuracy also diminishes on keeping the speed constant and varying the interval alone; the accuracy -of initial adjustment is favoured by a short interval, accuracy of current control by a low speed ; fatigue increases the vari- ability of a performance, but practice decreases it, variability means improvability. Finally, the author advocates a new mode of writing, as he finds that the side to,side movement of the wrist and forearm possesses advantages in point of ease and of speed over the usual thumb-and-finger movement, or a movement of the whole arm from the shoulder. Dr. MArrIo BARatTTa has contributed a preliminary sketch of his work on the Latian earthquakes to the Rivista Marittima for August. He shows that the more important shocks are ‘connected with certain definite seismic centres, the positions of which he determines. An interesting comparison is made ‘between the earthquakes of an extinct volcanic region, such as the Alban Hills, and those which precede, accompany and follow an eruption of an active volcano such as Etna. In both, the disturbed areas are as a rule extremely small, and yet near their centres the shocks may be strong enough to damage ‘buildings. Also, in successive shocks, there are many changes in the positions of the epicentral areas. M. A. DE GRAMONT sends a reprint of an article de- scribing a method he has devised tor varying the scale and dispersion of a laboratory spectroscope (Comptes rendus, vol. exxviii., p. 1564, June 1899). The scale is adapted in the usual way by placing it at the end of a collimator tube and arranging that the light from the scale shall be reflected from one face of the prism into the observing telescope; but instead of having only one lens in the scale tube, fixed at its principal focus from the scale, there are two lenses there, whose distances from each other and from the scale can be varied by known amounts. It will be at once apparent that the effect of this will be to alter the magnification of the scale as seen in the observing telescope, and in practice the scale is so altered that a certain number of divisions always correspond to the distances between the same two spectrum lines, whatever kind of prism or dispersive arrangement is being used. The variation in the dispersion is obtained in a well-known but little used manner, by rotating the prism about its refracting edge, and using positions more or less removed from that of minimum deviation, the dispersion being increased or decreased accordingly as the prism is turned towards the collimator or telescope from the mean position. A useful diagram is given bringing together the various effects on the dispersion by gradual displacements of the prism. The author is investigating more closely the variation of dispersion with the angle of incidence, and will communicate results later. AN observation of some interest in connection with recent discussions on heredity is recorded by M. Casimir de Candolle in a paper read before the Socé#é de physique et a histoire naturelle de Geneve. He points out a constant difference between the normal and the adventitious buds of trees. The latter he regards as new individuals of the same species as the tree from which they spring, or as apogamic embryos, while the former are simply organs for prolonging the life of the indi- vidual. It is quite common for the first leaves of a woody plant to differ in form or structure from the later leaves. Examples NO. 1562, VOL. 60] are given in Lucalyptus globulus, the walnut, the horse-chestnut, and the hornbeam. In all these cases the first leaves from adventitious buds resemble, not those from normal buds, but the first leaves of the young plant. A SECOND edition of Dr. M. M. Richter’s tables of carbon compounds is in course of publication by the firm of Leopold Voss, Hamburg and Leipzig (London: Williams and Norgate), under the revised title of ‘* Lexikon der Kohlenstoff-Verbin- dungen.’’ How tremendous has been the advance in the know- ledge of carbon compounds since the original work appeared may be judged by the fact that the total number of compounds. registered in the new edition is 67,000, as compared with 16,000 known in 1883. The work will be an index to Beil- stein’s handbook of organic chemistry, for all the compounds— about 57,000—contained in Beilstein are dealt with. Papers published up to the end of last year have been used in the preparation of the volume, and it is intended to publish annual supplements in order to keep the work up to date. The “* Lexikon” will be completed in about thirty-five parts, twelve of which have been issued. Messrs. WHITTAKER AND Co. have published a second edition, thoroughly revised, of ‘‘ An Introductory Course of Practical Magnetism and Electricity’ by Mr. J. Reginald Ashworth. The book contains an admirable course of ex- perimental work suitable for students in ‘‘ Schools of Science” and other institutions where physics is taught by laboratory practice. A number of new illustrations have been added to assist students to understand descriptions of experiments. CALENDARS, for the session 1899-1900, have reached us from the Merchant Venturers’ Technical College, Bristol, and the Birkbeck Institution, London, in each of which all necessary information is to be found as to the various activities in con- nection with the two institutions. We notice that at the Merchant Venturers’ College certain extensions and improve- ments have recently taken place ; ¢.g. a new optical laboratory has been opened in connection with the Department of Applied Physics and Electrical Engineering, the amount of space avail- able for the dynamo and testing-room has been doubled, and a battery, &c., have been added to the equipment. In addition to these, other changes have either taken place or are in progress. Two articles of scientific interest are to be found in the current issue of the Mzmanztarian—one, by Mr. E. W. Brabrook, entitled ‘‘ Anthropology, 1863-1899”; the other, by Dr. D. Somerville, on ‘‘The Rise of Bacteriology.” Each gives in brief outline some idea as to what has been accom- plished in the two branches of science. A reproduction of a striking photograph of Mr, Brabrook forms a frontispiece to the number, WE are asked to say that the lectures to young people, referred to in the last issue of NATURE, p. 538, are to be delivered by Mr. Cecil Carus-Wilson during the months of October and November, and not as was stated. THE additions to the Zoological Society’s Gardens during the past week include five Barbary Turtle Doves (Zzrtur rzsorius) from Africa, presented by Mrs. J. A. Moore; one Ruffed Lemur (Levzwx~ varius) from Madagascar, two Westermann’s Eclectus (Zclectus westermannz) from Moluccas, a Two-spotted Paradoxure (Paradoxurus binotata) from West Africa, a Rufous Tinamon (Rhynchotus rufescens) from Brazil, a Grey Ichneumon (Herpestes gréseus) from India, four Blanding’s Terrapins (Zyzys blanding?) from North America, deposited; a Black-necked Swan (Cygnus négrécollis) from Antarctic America, a Hoopce (Upupa epops), two Sandpipers (Zrzngo¢des hypoleucus), European, two Lanceolated Jays (Garru/us lanceolatus) from the Himalayas, purchased. OcTOBER 5, 1899] NATURE 55! OUR ASTRONOMICAL COLUMN. ASTRONOMICAL OCCURRENCES IN OCTOBER :— October 7. 10h. 18m. Minimum of Algol (8 Persei). g. 14h. Saturn in conjunction with the moon (kh 27’ N.). 10. 7h. 7m. Minimum of Algol (8 Persei). 10. 7h. 3m. to 8h. 1om. Occultation of 4 Sagit- tarii (mag. 4°6) by the moon. 11. 5h. Mars in conjunction with Jupiter, g1° 11'S. 14. Vesta (mag. 6°5) in opposition to the sun. 15. Venus. Illumination portion of disc Mars, 0981. 16. 6h. 3m. to 7h. 2m. Occultation of 16 Piscium (mag. 5°6) by the moon. 16. Ith. 53m. to 13h. Occultation of (mag. 5°2) by the moon. 18-20. Epoch of the October gI°+15°). 21. 8h. 37m. to gh. 35m. Occultation of K! Tauri (mag. 4°6) by the moon. 21. 8h. 38m. to 9h. 34m. Occultation of K? Tauri (mag. 5°5) by the moon. O°99I ; 19 Piscium Meteors (Radiant, 26. 6h. Venus in conjunction with a _ Libre. 9 0 6'’N. 29. 13h. Venus in conjunction with Jupiter. 9 o 33'S. 30. 8h. 50m. Minimum of Algol (6 Persei). Comet E. GIAcoBINI.—A telegram has been received from the Centralstelle at Kiel announcing the detection of this comet at the Nice Observatory for the first time during the present apparition. The observation was as follows :— R.A. 16h. 26m. 32s. Decl.—5° 10’ The daily motion in right ascension is + 2m. and in north polar distance — 10’, so that the comet is moving slowly in a north-easterly direction. The position at the time of discovery on September 29 was about 3° north of the 5th magnitude star, wv Ophiuchi. The comet is merely described as ‘‘ faint.” Previous appearances of this visitor took place in September 1896 and June 1898. A later telegram from Kiel announces that the comet has been observed at the Konigsberg Observatory, the measured position being :— 1899. Oct. 1899. Sept. 29d. 8h. Nice Mean Time. R.A. 16h. 31m, 0°7s, Id, 8h. 075m. } Fc]. — 4° 30" 50" Two New VARIABLE Stars.—Dr. T. D. Anderson, of Edinburgh, announces in As/7. Mach. (Bd. 150, No. 3594) his discovery of two new variables. (1) Zz Herciules.—A star, not mentioned in the B.D., whose position is R.A. =17h. 53m. 27s. Decl. = + 19° 30’ (1855) was found in August to have a variation amounting to about 0’9 ofa magnitude. The star is about 2’ or 3’ north- preceding the 9°2 magnitude star B.D. + 19°°34809. (2) Zn Cygnus.—A star, not mentioned in the B.D., whose position is - R.A: =2oh. 9m. 44s. | Decl. = + 30° 37’ J (1855) is at present (September 21) rapidly diminishing in brightness. Comparisons with the neighbouring stars B.D. + 30°:3958, 3963, 3964 showed the variation in magnitude to be from 8°5 to 9°2. THE MELBOURNE OBpseRVATORY.—The thirty-third report of Mr. P. Barrachi, the Government Astronomer at the Melbourne Observatory, Victoria, has recently been distributed, showing the work undertaken and the progress made during the period July 1, 1898, to February 28, 1899. The observatory is reported in good order, the instruments well cared for and in good working condition. With the 8-inch transit circle 1571 observations have been made in right ascension, for determinations of azimuth, clock corrections and catalogue stars ; also 1017 observations in north polar distance have been made in connection with latitude determination, catalogue stars and special zodiac stars, The catalogue stars were intended chiefly to be used in the reduction of the plates for the astrophotographic catalogue. The zodiacal NO. 1562, VOL. 60] stars have been observed at the request of Dr. Gill, of the Cape Observatory, in connection with his heliometer observations of Neptune and the other major planets at opposition. All the reductions are well in hand. Astrophotographic Catalogue.—The series of plates for the catalogue is now completed, and 387 plates for the Chart have been passed as satisfactory. Special series have been taken for the region round the South Pole, and seven plates have been exposed for the Oxford chart type. The measurement of the plates is being undertaken by six young ladies, using three micrometers. The probable error of a measured coordinate is now no more than 0”'I, which is within the prescribed limit. The progress of this part of the work is rather slow, but trials with Prof. Turner’s scale, as adopted at Greenwich and Oxford, although permitting of much greater speed, showed the error to be as great as 0”°5, and therefore all the measurements are to be made with the filar micrometer. A new instrument, similar to that designed by Dr. Gill for the Cape, has been ordered from Messrs. Repsold and Sohne. The various operations connected with the time service, meteorological observations, and inspection of outlying depéts: have been carried out as in previous years. Terrestrial Magnetism.—The photographic registration of the horizontal and vertical components and of the magnetic declin- ation have been continued, absolute measurements and rede- terminations of scale zeros being made five times. The measure- ment and reduction of the curves obtained since 1867, numbering some 30,000, have been commenced. The photo-heliograph has been employed on sixteen days for solar pictures ; 264 pairs of cloud photographs have been ob- tained with cameras placed at different points round the observatory buildings. The great telescope and south equatorial have been used for comet and planetary observation, and for the use of visitors, 189 persons being admitted on Wednesday afternoons and 195, at night during the year. STR ANDREW NOBLE ON THE BEST EDUCATION FOR ENGINEERS.* WHEN your Dean first did me the honour to ask me to address you on the opening of your session, I had grave doubts as to whether I was a proper person to accept the in- vitation. On the one hand, I have had little or nothing to do with the education of others, and in some points my views, at all events so far as regards primary education, are at variance with much that is being done at the present day, but as, on the other hand, I have had exceptional opportunities of observing, both in this and other countries, certain points which seem to. me to be of importance to those who propose to uphold the in- dustrial supremacy of this country in the struggle which year by year other countries are rendering more and more severe, you therefore see me here to-day, and I shall consider myself amply rewarded if I can tempt but one of you to enter, for the sake of knowledge itself, the boundless fields which science day by day is opening up to you. I can promise that the pursuit will give you happiness. I hope it may give you wealth and distinction ;. but I remember the words of the Preacher, that riches are not always given to men of understanding, nor favour to men of skill, but that time and chance happen to us all. Technical education is a phrase that has been so often mis- used, perhaps so often misunderstood, that many of those who, like myself, are engaged chiefly in trying to solve the practical problems of engineering are in the habit of hearing it either with impatience or of regarding it as a fad of lay theorists, or sometimes, I fear, as a cloak for educational shortcomings in. other directions. And I am bound to confess, if their experi- ence has been the same as mine, that there is some excuse for them. You can form but little idea of the number of persons. of both sexes who have assured me that their sons had no taste for books, but had shown a marvellous talent for engineering. I need hardly tell you that the marvellous talent generally turns out to be an incapacity, possibly from. defective education, for seriously applying the mind to any subject whatever. ; But technical education, properly considered, is of the highest 1 Inaugural Address of the Session 1899-1900 of the City and Guilds Central Technical College, given at the College, Exhibition Road, by Sir Andrew Noble, K.C.B., F.R.S., on Tuesday, October 3. NATURE [OcTOBER 5, 1899 importance both to you and to England. that we have to guard against. Now one of the great abuses I take to be that technical education is often begun too early in life, that is, that it is substituted for a general education, and a boy attempts to put his knowledge to practical use before he has learnt how to fearn. Another abuse is the divorcing of practice from theory, and the danger of elevating practical application above scientific knowledge. I shall try, therefore, to-day to say a few words, firstly, about the necessity of acquiring a sound general education before any special, work is attacked, and, secondly, about the necessity of basing all practical work on theoretic knowledge. _ Lattribute the compliment which has been paid me in the invitation to speak at the opening of the present session to the fact of my having been connected, for many years past, with the management of probably the largest engineering firm in England. That. position has afforded me exceptional oppor- tunities for observing what educational antecedents are likely to produce the best results in the engineering field. I say “* exceptional opportunities ” advisedly, for we at present em- ploy in our various works not far removed from 30,00c hands. Of these a large number are youths ; often sons of workmen, but not unfrequently drawn from the class which I see repre- sented before me. I am continually asked what education I should recommend for a lad entering Elswick. I always say, ‘‘Send your son to as good a school as you can, keep him there as long as you can, do not curtail his time of schooling, do not stunt his early intellectual growth by narrowing it down to any special study as taught at elementary schools.’ Science, mechanical drawing, and such like are no doubt very useful (as all knowledge is useful) in their way. These studies may prove an irresistible attraction to minds with a strong bent towards scientific subjects, but I would fancy most employers would rather that a lad came to us blankly ignorant of both, so long as he had had a good education, had been taught, and had ability to think, and to concentrate his atten- tion on any subject brought to his notice. Some of you may have heard, no doubt, the answer of the Duke of Wellington to a father who asked him what was the best education for his son, preparatory to his joining the army : “The best education you can give him.” It was a very pregnant utterance, terse and to the point, as mearly all the great Duke’s were ; and it remains as true for any other profession as for the army. In nine cases out of ten, I should say, any knowledge acquired by a boy before he is sixteen can have but a slight intrinsic value. Up to that age, it is not z/a¢ he learns that we have to look at, but ow he learns ; it is the habit of dis- cipline, of mental application, of power in attacking a subject, that are so valuable ; not, generally, any definite piece of knowledge he may have gained. According to my experience, the most valuable knowledge It is only its abuse that a man has at his disposal is that which he has taught him-. self. That a special technical education is not an absolute necessity is not difficult of proof My own chief, Lord Arm- strong, commenced life as a solicitor; James Watt was an instrument maker, and was prevented from opening a shop in Glasgow because he had not served a {full apprenticeship. George Stephenson was an assistant fireman to his father at Killingworth Colliery. Faraday was brought up as a book- binder. I cite the cases of these great men simply to show how men without trained assistance have taught themselves, and what can be done by the dauntless energy, untiring industry and patient search after truth which were the great character- istics of all of them, and which enabled them to do such great things. My own impression with regard to early education is that, as a sharpener of the young intellect, and as a mental discipline, it would be difficult to improve upon the curriculum which is now in force at our public schools, and which, in the main, has been in force for so many centuries. Iam not in accord with those who think that modern lan- guages should supersede the classics as a means of education, and T should regret more than I do the attempts which have been made in this direction, did I think that these attempts were likely to be successful. Men of science will remember that practically the whole of our scientific nomenclature is NO. 1562, VOL. 60] borrowed from the Greek and Latin languages ; and, personally, I have found my own knowledge of the classics—which repre- sents, no doubt, that of a very ordinary schoolboy—stand by me, and enable me to enjoy, as I would not otherwise have done, that noble literature, which, as Lord Macaulay says, is the most splendid and perhaps the most durable of the many glories of England. - But, whatever may be the fate of the classics as a means, I must take up my parable against a course of education I have seen in several primary schools where an attempt is made to teach boys, often little better than children, rudimentary chemistry, rudimentary geology, also physiology and electricity. Occasional popular lectures on these sciences may be of very great value to some boys in interesting them in these great subjects, and in leading them, at some later date, seriously to study them, but these sciences as taught in the schools I refer to can have but little value in encouraging habits of thought, of application, and of mental discipline ; and to knowledge so acquired the words of Pope are peculiarly applicable :— ‘* A little knowledge is a dangerous thing, Drink deep or taste not the Pierian spring, There shallow draughts intoxicate the brain, And drinking deeply sobers it again.” I am aware that many people say that the years a boy wastes on Greek and Latin might be better employed in learning German and French. It may be so, but it is not difficult to teach these most important languages colloquially at a very early age; and with regard to technical subjects, speaking from my own observation, I may say that I do not think I have known any man at twenty-eight or thirty who was the better for having abandoned his general education for technical subjects at too early an age. Those men who, with fair abilities, have received a really good education, have been taught to use their minds, and who, by contact with other students, have acquired habits of appli- cation, amply make up for their late start by the power of mind and grip that they bring to their work. They are fresh and keen when others, who have been hammering away at semi- technical work from early boyhood, have become stale and are less vigorous, and that reflection moves me to deprecate strongly any attempt to teach seriously practical or electrical engineering in preparatory or elementary schools. As an excellent recreation, such studies are no doubt to be ‘encouraged, but to make them a systematic part of education, to the exclusion of studies which have a more direct effect in developing the understanding, seems to me to be entirely wrong. I would go further and say that even in public schools, and their equivalents, for older boys, what are termed engineering shops are generally a failure, so far as any efhcient knowledge to be gained in them is con- cerned. Except asa reasonable diversion for recreation hours, such ‘‘ shops” have, I fear, but little value, and in nine cases out of ten the hours spent in them are subtracted from the time due to more valuable studies. In my judgment, the age at which a boy should seriously begin any special studies, with a view to fit him technically for the profession he may have decided to follow, should not be earlier than seventeen or eighteen. And in any discussion as to the age at which a boy should leave school, the great incidental advantages that he gains from a reasonable prolongation of his schooldays must never be lost sight of. A stricter discipline, a wiser supervision, a more authoritative yet sympathetic advice as to conduct, are more possible at school than can ever be the case in after life, and a more constant and generous association with his equals rubs oft angularities and leads to amenity of disposition. It is seldom, indeed, that one cannot trace the difference between a lad who has had a full public school training and another who has been less fortunate. Speaking as an employer of labour, I should say that we find a pleasant speech and manner, tact in dealing with others, and some power of organisation of the utmost value ; and it is precisely those qualities which a boy acquires, or ought to acquire, in his /a¢er years at a public school. Without such qualities even the highest scientific attainments will never make a captain of industry, and in selecting candidates for appointments the man-of-business distinctly prefers a youth who has had the benefit of some years at a good school. So much for the necessity of grounding technical studies on the basis of a sound general education. The next point I should like to urge is that any practical tech- nical instruction and any practical knowledge acquired in the OcrosER 5, 1899] NATURE 553 workshop should be based upon sound theoretic knowledge. I am driven to enforce this question because (speaking again from my own observation) I find that in this country far too much weight is given to practical skill and what is called the “‘ rule of thumb” ; far too little to sound theoretic knowledge. In the middle of this century English machinery was im- measurably superior to any other. To our remaining content with this state of things, and to our seriously neglecting technical instruction, I attribute the very much greater comparative progress that Germany, the United States and Switzerland have made in the last fifty years, and, if I am not very greatly mistaken, we shall have before many years, in the East, an important commercial rival in Japan, since that country is de- veloping its manufacturing powers with an energy that is as remarkable as it is unexampled. Turning to other departments of indus no Englishman can ebserve without regret how certain branches have almost al- together abandoned this country, and been in a great measure feft to those who have paid more attention to technical instruc- tion. Nearly every requirement of a drawing office can be better and more economically obtained from Germany. From what source do all our pure chemicals come, our filter papers and most of our glass apparatus ? I admit that the workmanship of many articles made in England cannot be surpassed, but if we require any original or special piece of apparatus we are frequently compelled, as I have been, to go to Germany or france for their manufacture. I do not desire to press my point too far, and admit that a portion of this transference of work, which [ so much regret, may be due to cheaper labour. But the English mechanic is second to none, and if that false trade unionism, which en- deavours to prevent the most intelligent and skilled from reaping the full benefit of their abilities, be abandoned, I do not despair of seeing this country regain much that it has now lost. But it is to theoretic and technical knowledge that we must chiefly look. Consider, as an illustration, electricity in the service of man. Think of its innumerable applications, and of the number of hands dependent upon its industries. But for one man capable of designing or improving these powerful machines or delicate instruments, there are a thousand ready and able to carry out their designs. But it is the former who are the salt of the earth, and those who have the management of large concerns know well how to value them. It was to»meet the want that I am referring to that your Technical College was founded. Its objects are admirably stated in its programme, and your attention is drawn to the undoubted fact that no theoretic or technical instruction can supersede the necessity of obtaining practical experience in the workshop and factory. But, on the other hand, I believe that mo genuine success in the higher walks of industry is probable without thorough theoretic or technical knowledge. In my experience I do not think I have ever known a man rise to the top of the tree without it. I may, perhaps, be for- given if I refer to one great engineering genius, Lord Arm- strong, with whom it has been my privilege to be so long and so intimately connected. In whatever investigation he was en- gaged, he added to sound theoretic knowledge an intensity of application and an apparently intuitive perception of the results to be expected that I have rarely seen equalled. Of him it may be truly said that ‘‘ whatever his hand found to do, he did it with his might.” Sir William Harcourt, speaking a fortnight ago, attributed the immense commercial advance which has recently been made by Germany to the better teaching of languages, and to the 4serman merchant being able to speak to the English buyer in a tongue which he can understand. I very much doubt if that has much to do with the matter, and I am sure that houses where business is done on a large scale very much prefer that all letters should be in the languages of the respective writers, and not in the doubtful English that is not unfrequently thrust upon us. There is no doubt that Germany is competing with us, as she has a right to do, successfully ; and, so far as I am aware, with respect to her manufactures, perfectly honestly. I say “‘ honestly,” because I do not believe in any attempt to enhance the value of one’s own wares by depreciating those of other people ; and I entirely differ from those who would attri- bute the success of our German competitors to their putting on the market inferior goods specially got up to imitate those of a superior class. It was some idea of this kind, no doubt, that led NO. 1562, VOL. 60] to the most ill-advised regulation that foreign-made yoods should be stamped so as to show their origin. It doubtless does this, but its effect is, I believe, in the direction of an adver- tisement for foreign goods, and there is some danger that if our own manufacturers relax their efforts the ‘‘ madein Germany,” which was, I think, meant to be a reproach, should become, on the contrary, a hall-mark of excellence, as when the W2lhelm der Grosse, one of the finest steamships afloat, steamed into Southampton water with a facetious placard, ‘‘ Made in Ger- many,” hanging on her side. In many articles, and especially with the apparatus of scientific research to which I have referred, this is already the case. Manufacturing progress has in Germany gone hand in hand with material progress, and any one who has travelled much must be astounded with the extraordinary improvement which has been going on in recent years, not only in German railways, shipbuilding and steel-working, but also in the buildings, order and general amenities of life of the great German cities, such as Berlin, Frankfurt and Cologne. In the competition of manu- facture we are pressed very hard from steel to watches, from marine engines to scientific instruments. In nothing, indeed, have German manufacturers made more progress than in the making of all exactinstruments. In these departments Germany certainly excels us, so far as original and inventive improvement is concerned. Now, all this improvement, I feel inclined to attribute, not, with Sir William Harcourt, to any linguistic superiority, but to the far greater opportunities of technical study which are afforded in Germany. If we are to hold our own, we older men must try to multiply these opportunities of study in our own country, and you younger men must do your part by seeking to avail yourselves to the uttermost of any such opportunities provided. To you, gentlemen, who are about to commence the studies which will be useful to you in your future career, I venture to say a few words. Consider the marvellous progress that has been made in the physical and practical sciences during the century now rapidly drawing to a close. At the commencement of the century steam navigation and railways were unknown and unachieved. Our knowledge of the science of electricity was confined to a few isolated phenomena, and chemistry was in its infancy. Now the latter science has spread its branches until it seems likely it may bring into a common brotherhood the whole of the physical sciences. Consider, further, that knowledge and progress appear to be increasing in a geometric ratio ; who then can predict what will be the progress made at the conclusion of the twentieth century, or even during the first half of it? In forwarding’ that progress I sincerely trust that many of those whom I now address may be prominent workers. We have never wanted in this country the men whom I would call the captains of the scientific army, but I think we are much inferior to Germany in the rank and file, in the number of men who are willing to follow particular lines of investigation, and who thus do invaluable service to science. We older men, whose careers are approaching their termin- ation, cannot but look with envy on the career which may be open to some of you. It was said of the telescope, which opened to our vision infinite space, that it was balanced by the microscope, which showed us the infinitely small ; but small as are these objects, the kinetic theory of gases opens up to our appreciation, I had almost said to our view, molecules whose dimensions are inconceivably smaller. It would be vain to name to you the limiting dimensions of these molecules which have been revealed to us by the labours of Maxwell, Lord Kelvin, Clausius and others, but I have seen somewhere, possibly in the columns of NATURE, a statement which may be more in- telligible. It was something like this:—That though the molecules of hydrogen gas are so small that it would take about 50 millions touching one another to make an inch, they are so numerous in a cubic inch of gas at 0° Centigrade and atmospheric pressure, that if the whole of them were formed into a row, they would go round the circumference of the earth more than a thousand times. The molecules also, as you probably know, are in violent motion. The highest velocity I have obtained with a projectile nearly reached 5000 f.s., but the average velocity‘,of the hydrogen molecules at the temperature and pressure I have named is somewhat more. I once calculated that a few molecules, I forget in how many millions, might exceed 50,000 f.s. We smile, and justly smile, at the seekers after what was 554 NATORE [OcToseEr 5, 1899 called perpetual motion. Modern science seems to show that it is equally vain to seek for anything that is perpetually and absolutely at rest. I have alluded to the kinetic theory of gases because we know more of the constitution of that form of matter than we do of any other, but having regard to the progress of science to which I have referred, is it too much to hope that some of you will live to see a second Newton, who will give you a second Principia, which shall clear away the difficulties which surround the con- stitution of matter whether ponderable or imponderable ? One word more, bring enthusiasm to your studies ; without it the best instruction (this you will have) and the best apparatus will do nothing for you. Make your work the first aim, and do not let athletics, or anything else, take precedence of it. Here, again, I cannot help thinking that the Germans get a little the better of us. With them work is absolutely in the forefront ; I am not at all sure that it is so with the average young English- man of to-day. No one appreciates the value of athletics, when kept in their proper place, more keenly than Ido. But against the substitution of athletics for the more serious objects of life, I should like to enter my strongest protest, and it will be a sorry day for England if such a change ever takes place. Lastly, I would say to you, while giving the acquiring of knowledge that may assist your own business or profession the first place, not be too utilitarian, do not narrow the search for knowledge down to a search for utilitarian knowledge, for knowledge that you think will pay. I remember a strong pro- test of De Morgan’s against the number of men who take their station in the business of life without ever having known real mental exertion ; he put it that knowledge which ought to open the mind was decided on solely by its fitness to manure the money tree. Therefore, above all things, pursue knowledge. It is that pursuit which will stand by you to the end as at once the greatest and the most enduring of pleasures. Friends may die ; the most tender attachments must be severed ; advancing years will very soon debar you from any serious pursuit of athletics ; the acquisition of wealth will take away from you the pleasure of ‘making a position,” which is probably the keenest, and surely the most legitimate, incentive of middle life; but the pleasure of acquiring knowledge will console you to the last, so long as you have strength to open a book, or to hold a test- tube. Cry after knowledge ; seek for her as silver ; and search for her as for hidden treasure. THE BRITISH ASSOCIATION. SECTION H. ANTHROPOLOGY. OPENING ADDRESS BY C. H. READ, SECTION. THE difficulties that beset the President of this Section in pre- paring an address are chiefly such as arise from the great breadth of our subject. It is thought by some, on the one hand, to comprehend every phase of human activity, so that if a communication does not fall within the scope of any other of the Sections into which the British Association is divided, it must of necessity belong to that of anthropology. On the other hand, there are many men, wanting neither in intelligence nor education, who seem incapable of grasping its general extent, but, mistaking a part for the whole, are fully content with the conclusions that naturally result from such a parochial method of reasoning. The Oxford don who stated, a year or two ago, his belief that anthropology rested on a foundation of romance can only have arrived at this opinion by some such in- adequate process, and the conclusion necessarily fails to carry conviction. The statement was, however, singularly ill-advised, for anthropology gives way to no other branch of science in its reliance upon facts for its existence and its conclusions. Had the reproach been that the facts were often of a dry and repel- lent character we might have pleaded extenuating circumstances, but I fear it must have been admitted that there was some justice in the complaint, though we could fairly point to instances where master minds have made even the dry bones of anthro- pology live, and that without trenching upon the domain of romance. It is not, however, my purpose to-day to enter upon a general defence of anthropology as a branch of science. It has taken NO. 1562, VOL. 60] PRESIDENT OF THE far too firm a hold upon the popular mind to need any such help. Tintend rather to treat of one or two special subjects with which I am in daily relation, in order to see whether some practical means cannot be found to bring about a state of things more satisfactory than that at present existing. The first of these branches is that of the prehistoric antiquities of our own country. It will not be denied that there can be no more legitimate subject of study than the remains of the in- habitants of our islands from the earliest appearance of man up to the time when written history comes to the aid of the archzeo- logist. There is no civilised nation which has not devoted some part of its energies to such studies, and many of them under far less favourable circumstances than ours. The chiefest of our advantages is to be found in the small extent of the area to be explored—an area ridiculously small when compared with that of most of the continental nations, or with the resources at our com- mand for its exploration. The natural attractions of our islands, moreover, have also had a great influence on our continental neighbours, so that their incursions have not been few, and no small number of them decided to remain in a country where the necessaries of life were obtainable under such agreeable condi- tions. The effect of these incursions, so far as our present subject is concerned, is that there is to be found in the British Islands a greater variety of prehistoric and later remains than is seen in most European countries, a fact which should add con- siderably to the interest of their exploration. At the same time also it must be borne in mind that it is by such researches alone that we can arrive at any true understanding of the conditions of life, the habits and religious beliefs, or the physical characters of the varied races who inhabited Britain in early times. It may seem unnecessary to urge, in face of these facts, that all such memorials of the past should be, in the first place, pre- served ; and, in the second, that any examination of them should be undertaken only by properly qualified persons. Un- fortunately, however, it has never been more necessary than it is at the present time to insist upon both points, and the fact that these prehistoric remains are scattered impartially over the whole country, with the exception, perhaps, of the sites of ancient forests, makes it almost impossible to devise any special measures for their preservation. An additional difficulty is to be found in the fact that many ancient remains, such as the barrows of the early Bronze Age, are altogether unrecognised as such, and in the process of cultivation have been ploughed down almost to the level of the surrounding surface, until at last the plough scatters the bones and other relics unnoted over the field, and one more document is gone that might have served in the task of reconstructing the history of early man in Britain. Such accidental and casual destruction is, however, probably unavoidable, and, being so, it is scarcely profitable to dwell upon it. We can, perhaps, with more advantage protest against wilful destruction, whether it be wanton mischief or misplaced archeological zeal. An enlightened public opinion is our only protection against the first of these, and will avail against the second also, but we are surely entitled to look for more active measures in preventing the destruction of archzological monu- ments in the name of archeology itself. It is a far more common occurrence than is generally realised for a tumulus to be opened by persons totally unqualified for the task either by experience or reading. An account may then be printed in the local journal or newspaper. When such accounts do appear it is often painfully obvious that an accidental and later burial has been mistaken for the principal interment, while the latter has been altogether overlooked, and no useful record has been kept of the relative positions of the various objects found. The loss that science has suffered by this indiscriminate and ill-judged exploration is difficult to estimate, for it should be borne in mind that an ancient burial, once ex- plored, is destroyed for future searchers—no second examination can produce results of any value, though individual objects over- looked by chance may repay the energy of the later comers. So much varied knowledge is, in fact, required for the proper elucidation of the ordinary contents of a British barrow that it is almost impossible for any single person to perform the task unaided. A wide experience in physical anthropology must be combined with ar acquaintance fully as wide with the ordinary conditions of such interments and the nature, material, and relative positions of the accompanying relics, all of. which must be brought to bear, with discriminating judgment, on the facts laid bare by the digger’s spade. Added to this, the greatest precaution is needed that nothing of value be overlooked. In OcrToBER 5, 1899] some soils, such as a stiff clay, it is almost impossible to guard against such a casualty, especially when the barrow is of large size and vast masses of earth have to be moved. The amount of profitable care that may be bestowed on scientific work of this character can nowhere be’ better seen, Iam glad to say, than in our own country, in the handsome volumes produced by General Pitt-Rivers as a record of his investigations in the history of the early inhabitants of Dorsetshire. The memoirs contained in them are unsurpassed for scientific thoroughness, and they will probably long stand as the model of what archzeological investigation should be, It is very seldom, however, that circumstances conspire so favourably towards a desired end as in the case of General Pitt-Rivers, where a scientific training is joined to the love of research, and finally ample means give full scope for its practice under entirely favour- able conditions. While it is, perhaps, too much to expect that all explorations of this character should be carried through with the same minute attention to detail that characterises General Pitt-Riyers’s diggings, yet his memoirs should be thoroughly studied before any work of the same kind is entered upon, and should be kept before the mind as the ideal to be attained. It is not too much to say that a diligent study of the works of the two foremost explorers of prehistoric remains in this country— Canon Greenwell and General Pitt-Rivers—will of itself suffice to qualify any intelligent antiquary to conduct the exploration of any like remains. At the same time, it must not be forgotten that exploration is one thing and a useful record of it is another, and here the explorer would do well to invite the co- operation of specialists if he would get the full value out of his work, and there is generally little difficulty in getting such help. Thane ventured to point out, in moderate terms, the dangers to which a large number of our prehistoric sites are liable, and to state under what conditions they should be investigated. It is not unreasonable to expect, if the danger is so obvious, that a remedy should be forthcoming to meet.it. In most of the continental States it would be easy to institute a scheme of State control by which such sites would vest in the Government to just such an extent as would be necessary to prevent their being destroyed, and such a scheme might be cheerfully accepted and applied with success in any country but our own. Here, however, we are so accustomed to rely upon individual influence and exertion in matters of this kind, that an appeal to the Government is scarcely thought of; while, on the other hand, the rights of property are fortunately so safeguarded by our tradition and law that nothing but a futile Act of Par- liament would have the least chance of passing. Moreover, experience teaches us that it is not to State control that we must look. The Ancient Monuments Bill, which was intended to protect a special class of monuments, and was framed with a full regard to the rights of owners, still stands in the Statute Book, but for years past it has had no effective value whatever. That being so, we must look to private organisations, and preferably to those already in existence, for some effectual moral influence and control, and, in my judgment, the appeal could best be made to the local scientific societies. Many of these are very active in their operations, and could well bear an addition to their labours ; others, less active, might become more energetic if they had a definite programme. The plan I would propose is this :—Each society should record on the large scale Ordnance map every tumulus or earthwork within the county, and at the same time keep a register of the sites with numbers referring to the map, and in this register should be noted the names of the owner and tenant of the property, as well as any details which would be of use in exploring the tumuli. I am well aware that a survey of this kind has been begun by the Society of Antiquaries of London, and is still in progress ; but this is of a far more com- prehensive character, and is, moreover, primarily intended for publication. The more limited survey I now advocate would in no way interfere with it, but, on the contrary, would provide material for the other larger scheme. Once the local society is in possession of the necessary information just referred to, it would be the duty of its executive to exercise a beneficent con- trol over any operations affecting the tumuli, and it may safely be said that such control could in no way be brought to bear so easily and effectively as through a local society. Some of the arguments in favour of some such protection for our unconsidered ancient monuments have been already briefly stated, and, in conclusion, I would only urge this in their favour, NO. 1562, VOL. 60] NATURE 555 that while the more beautiful monuments of later and historic times are but little likely to want defenders, the less attractive early remains are apt to disappear not so much from want of appreciation as from want of knowledge, and I would repeat that it is from them alone that we can reconstitute the life- story of those who lived in what we may, with truth, call our dark ages. I will now ask you to turn your attention to another matter in which it seems to me that this country has opportunities of an unusually favourable kind. I refer to the collection of anthro- pological material from races which still remain in a fairly primi- tive state. It is somewhat trite to allude to the extent of our Empire and the vast number of races either subject to our rule or who look to us for guidance and protection. The number may be variously computed according to the bias, philological or physical, of the observer, but it will not be con- tested that our opportunities are without precedent in history, nor that they greatly exceed those of any existing nation. That being so, it may not be useless to see how far these oppor- tunities are utilised. While it will not be denied that the Indian Government and the Governments of some of our Colonies have done excellent work in the direction of anthro- pological research and publication, and that exhaustive reports from our Colonial officials are frequently received and after- wards entombed in parliamentary papers, yet it is equally clear that work of this kind is not a part of our administrative system, but rather the protest of the intelligent official mind against the monotony of routine. The material, the opportunity, as well as the intelligence and will to use both, are already in existence, and all that is now wanted is that the last should be encouraged, and the work be done on a systematic plan, and, as far as may be, focussed on some centre where it may be available for present and future use. It was for this end that I ventured to bring before the British Association at the Liverpool meeting a scheme for the establishment of a central Bureau of Ethnology for Greater Britain. Frequent appeals had been made to me by officials of all kinds in distant parts of the Empire to tell them what kind of research work they could most usefully undertake, and it seemed a pity not to reduce so much energy and good will into a system. Hence the Bureau of Ethnology. The Council of the Association, on the recommendation of the Committee, in- vited the Trustees of the British Museum to undertake the working of the Bureau ; this they have accepted, with the result that if the Treasury will grant the small yearly outlay it will be under my own supervision. If I had foreseen this ending I might have hesitated before starting a hare the chasing of which will be no sinecure. It was considered necessary, before attempting to begin the work of the Bureau by communicating with commissioners and other officials in the various Colonies and Protectorates, to lay the matter before Lord Salisbury and to invite his approval of the scheme. The whole correspondence will appear in the Report of the present meeting, but I may be pardoned for quoting one paragraph of the circular letter from the Foreign Office to the several African Protectorates. It is as follows: ‘* Lord Salisbury is of opinion that Her Majesty’s officers should be encouraged to furnish any information desired by the Bureau, so far as their duties will allow of their doing so, and I am to request you to inform the officers under your administration accordingly.” Whenit is remembered that this is strictly official phraseology, its tenor may be considered entirely satisfactory, and there can be little doubt that other departments of the Government will recognise the utility of the Bureau in the same liberal spirit. Thus we shall have within a short time an organisation which will systematically gather the records of the many races which are either disappearing before the advancing white man, or, what is equally fatal from the anthropological point of view, are rapidly adopting the white man’s habits and forgetting their own. The Bureau of Ethnology, however, will only perform a part of the task that has to be done. While there is no doubt of the value of knowledge as to the religious beliefs and customs of existing savages, it is surely of equal importance that anthro- pological and ethnological collections should be gathered together with the same energy. The spear of the savage is, in fact, far more likely to be replaced by the rifle than is his religion to give way to ours, Thus the spear will disappear long before the religion is forgotten. It may be said that we have collections of this kind in plenty, and it is true that in the British Museum, at Oxford, Cambridge, Liverpool, and Salisbury, there are indeed 556 NAPRORE [OcroBER 5, 1899 excellent collections of ethnology, while at the College of Surgeons and the Natural History Museum there are illustrations of physical anthropology in great quantity. Whatever might be the result if all these were brought together, there can be no question that no one of them meets the requirements of the time. Here also there isa want of a system that shall at once be worthy of our Empire and so devised as to serve the ends of the student. Where, if not in England, should be found the completest collections of all the races of the Empire? It must be admitted, however, not only that we have no national collection of the kind, but that other nations are ahead of us in this matter. This could be readily understood if their sources of supply were at all comparable to ours. But this is, of course, very far from being the case. The sources are ours in great part, and if we stand inactive it is not unlikely that some will be exhausted when we do come to draw upon them. It is, perhaps, better to give here a case in point rather than to rely on general statements. In the summer of last year I arranged, with the approval of the Trustees, that Mr. Dalton, one of the officers of my department, should make a tour of inspection of the ethnographical museums of Germany, with a definite object in view, but at the same time that he should make a general survey of their system and resources as compared with our own. The report which he drew up on his return was printed and has recently been communicated to the newspapers ; it is therefore not necessary to allude to it now, except to quote one instance confirming my statement that it is to a great extent from our Colonies that material is being drawn. Mr. Dalton says: “On a moderate estimate the Berlin collections are six or seven times as extensive as ours. To mention a single point, the British province of Assam is represented in Berlin by a whole room and in London by a single case.” But even this, forcible though it is, does not adequately represent the vast difference between the material at the disposal of the two countries. For it is the habit of the collectors for the German museums to procure duplicates or triplicates of every object, for the purposes of exchange or study. It is thus not unlikely that the whole room referred to represents only a part of the Berlin collection from the British province of Assam. In making these ob- servations, I should be sorry if it were thought that I wish to advocate a dog-in-the-manger policy, or that I consider it either desirable or politic to place any restriction upon scientific work in our Colonial possessions, even if such restrictions were possible. I would prefer to look at the matter from an entirely different point of view. If the German people, who are admittedly practical and business-like, think it worth while, with their limited Colonies, to spend so much time and money on the establishment of a royal museum of ethnography, how much more is it our duty to establish and maintain one, and ona scale that shall bear some relation to the magnitude of our Empire. The value of such museums is by no means confined to the scientific inquirer, but they may equally be made to serve the purpose of the trader and the public at large. How can we best obtain such a museum ? That is the question that we have to answer. It is scarcely profitable to expect that the Government will be stirred to emulation by the description of the size and resources of the Museum fiir Volkerkunde in Berlin. In the British Museum there is at the present time only the most limited accommodation even for the collections already housed there, and I am well aware that these form a very inadequate representation of the subject. It may be thought that the solution of this difficulty is easy. It is well known that the Government has purchased the rest of the block of land on which the British Museum stands, and it may seem that such a liberal extension as this will form should be enough for, at any rate, a generation or two, and that a little additional building would meet immediate wants, and enable the collections, now so painfully crowded, to be set out in an instructive and interesting way. I admit that if the whole of the contemplated buildings were at this moment complete, and at least double as much space given to the ethnographical col- lections as they occupy at present, the difficulty would be much simplified. The collections could at any rate be then displayed far more worthily and usefully. Even this, however, would hardly meet the case, even if there were a certainty of the buildings being immediately begun. Such works as these, how- ever, can only be executed in sections during the course of each financial year. Thus, even if a Chancellor of the Exchequer could be found to fall in entirely with the views of the Trustees, it would still be an appreciable number of years before the com- NO. 1562, VOL. 60] pletion of the entire range of galleries that is contemplated. For this reason alone I do not look forward to obtaining the space that is even now urgently wanted for some time. Meanwhile the natural and legitimate increase of the collections at the rate of about 1 to 2 per cent. per annum still goes on, and the original difficulty of want of room would still face us, though in a lesser degree. This estimate of the rate of increase may seem a high one; but it should not be forgotten that the science is new, and that it is only within the last few years that such collections have been made on scientific lines, instead of being governed only by the attractive character or rarity of the object. The gaps that exist in such a series as that of the British Museum, made in great part on the old lines, are relatively more numerous than would be the case in museums more recently founded. Another reason, equally cogent, for allowing far more room than is required for the mere exhibition of the objects is that, in my judgment, ethnographical col- lections, to be of real value, need elucidation by means of models, maps and explanatory descriptions, to a far greater extent than do works of art, which to the trained eye speak eloquently for themselves. Such helps to understanding necessitate a considerable amount of space, though the outlay is fully justified by |their obvious utility, and in any general scheme of rearrangement of the national collection they should be considered an essential feature. There is yet another factor to be considered. It has been the fashion in this country to consider remains illustrating the physical characters of man to belong to natural history, while the productions of primitive and uncultured races generally find a place on the antiquarian side. Thus the skull of a Maor will be found at the natural history branch of the British Museum, while all the productions of the Maori are three miles distant in Bloomsbury. Such an arrangement can perhaps be defended on logical grounds, but its practical working leaves much to desire, and the arguments for a fusion of the two are undoubtedly strong. For instance, the student of one branch would be unlikely to study it alone without acquiring a know- ledge of the other, while the explorers to whom we look for collections usually give their attention to both classes of anthropological material. Here again, in such a case, there would be a call for still more space at Bloomsbury. If I may be permitted to add one more to the requirements of what should be an attainable ideal, I should like to say that courses of lectures on anthropology delivered in the same building that contains the collections would form a fitting crown to such a scheme for a really Imperial museum of anthropology as I have endeavoured to sketch. There is but one chair of anthropology in this country, and admirably as that is filled by Prof. Tylor, he would himself be the first to admit that there is ample room and ample material to justify the creation of a second professorship. It will be admitted that if my premisses are well founded the conclusion must necessarily be that we cannot look to the British Museum to furnish us eventually with the needful area and other resources for the installation of a worthy museum of anthropology. The difficulties are far too great for the Trustees to overcome, unless by the aid of such an exhibition of popular enthusiasm as I fear our branch of science cannot at present command. Failing the British Museum, which may be called the natural home of such a collection, we must look elsewhere for the necessary conditions, and I think they are to be found, although it is possible that, however favourable these conditions may seem from our point of view, difficulties may already exist or arise later. It is not the first time that a scheme has been thought out for the establishment of a museum or kindred institution which should represent our Colonies and India. In the year 1877 the Royal Colonial Institute made a vigorous effort in this direction, and, in combination with the various chambers of commerce throughout the country, advocated the building of an ‘‘ Imperial} Museum for the Colonies and India” on the Thames Embank- ment, with the then existing India Museum as a nucleus. The arguments then brought forward were in the main commercial, but they are, if anything, more forcible now than they were twenty years ago. The competition with foreign countries has become keener on the one hand, while the bonds between the Colonies and the parent country are notoriously closer and more firm than at any previous time. No moment could thus be more opportune than the present for the foundation of a really Imperial Institution to represent our vast Colonial Empire. OcrToBER 5, 1899] WATURE yi The last sentence has, perhaps, given an indication of my solution of the question. The Imperial Institute at South Ken- sington has now been in existence for some time, and has passed through various phases. But its most enthusiastic supporters will scarcely claim for it entire success in its mission. What- ever may be the underlying causes, it must be admitted that such popular support as it possesses is scarcely founded on the performance of its functions as an Imperial Institute. It would seem, therefore, that something more is wanted—a more definite raison @’étre—than it has at present, and this I think it will find in being converted into such a museum of anthropology as I have indicated, but, of course, as a Government institution. I am by no means an advocate of the creation of new institutions, if the old ones can adequately do their work, nor do I think that anything but ill would result from a general partition of the contents of the British Museum. The separation of the natural history from the other collections was painful, though inevitable, and no such severe operation can be performed with- out loss in some direction. But the remoyal of the ethno- graphical and anthropological collections from the British Museum to the galleries of the Imperial Institute would possess so many manifest advantages that the disadvantages need scarcely be considered. The Government has already taken over a portion of the building for the benefit of the University of London. The remaining portion would provide ample ac- commodation for the anthropological museum, as well as for the commercial side, that might properly and usefully be continued ; its proximity to the natural history branch of the British Museum would render control by the Trustees easy; the Indian col- lections, which formed so important a feature in the scheme of 1877, are at this moment under the same roof; and finally the University of London has but to found a chair of anthropology, and the whole of the necessary conditions of success are fulfilled. I have but little doubt that, wherever it might be placed, the creation of a distinct department of anthropology would of itself tend to the enrichment of the collections. It must be re- membered that it is only since 1883, when the Christy collection was removed to the British Museum, that the ethnographical collections there can claim any kind of completeness. Until then one small room contained the few important objects of this kind that had survived from the voyages of Cook, Wallis and the other early voyagers. The public did not expect to find ethnography in the British Museum, and it is, in fact, only within the last few years that it has been generally realised that a gallery of ethnography exists there. If it were placed in such a building as the Imperial Institute, it would still remain part of the British Museum, and be under the guardianship of its Trustees ; but it would obviously command more attention and support from the public than can be expected while it remains an integral part of a large institution which has as many aims as it has departments. I began this address by stating that it would have a practical application. I trust that to others it may seem that what I have ventured to suggest is not only possible of achievement, but would also be beneficial to the branch of science that we repre- sent. I should like to add that, as far as possible, I have tried to state the case as it would appear to one who regarded the situation from an entirely independent standpoint, and wishing only to discover the most practical solution of what must be ad- mitted to bea difficult question. My allegiance to the British Museum, however, may well have tinged my views, unnoticed by myself. There are many other subjects that might well have formed the subject of an address at the present time. On such occasions as these, however, it is, I think, advisable to select a subject with especial reference to the needs of the time, and I know of nothing that is at the present moment more urgent in this particular direction, and in my judgment it will tend greatly towards the true advancement of science, the object we all have at heart. SECTION I. PHYSIOLOGY, OPENING ADDREss By J. N. LANGLEY, F.R.S., PRESIDENT OF THE SECTION. ONE might suppose that physiology, dealing as it does for the most part with structures—such as nerves, and muscles, and glands—which every one has and has heard of, would be eminently a science the newer aspects of which every one could NO. 1562, VOL. 60] readily understand. And in this supposition one would be encouraged by the frequency of the references in English litera- ture to some part of our inner mechanism. More than a century and a quarter ago we find: ‘“‘If ’tis wrote against anything, ‘tis wrote an’ please your worships against the spleen, in order by a more frequent and more convulsive elevation and depression of the diaphragm, and the succussations of the intercostal and abdominal muscles in laughter, to drive the gall and other bitter juices from the gall-bladder, liver and sweetbread of his Majesty’s subjects, with all the inimicitious passions which belong to them, down into their duodenums.” It must, however, be recognised that many subjects which are most interesting to the physiologist either involve so much special knowledge, or are so beset with technical terms, that it is difficult to make clear to others even their general drift. Iam not without uneasiness that my subject to-day may be found to fall within this category. I propose to consider some relations of the nerves which pass from the brain and spinal cord, and convey impulses to the other tissues of the body—the motor or efferent nerves ; and in especial the relations of those efferent nerves which run to the tissues over which we have little or no voluntary control. It is as well to say at once that none of the general conclusions which I lay before you are encrusted with universal acceptance. One or two have been subjects of con- troversy for the last fifty years; others are too young to have met even with contradiction. I do not propose to give you an account of the various theories which have been put forward on the questions I touch upon, nor do I propose to point out how far the views I advocate are due to others. I am concerned only to state what seems to me to be the most probable view with regard to certain problems which have been emerging from obscurity in recent year. Limitations in the Control of the Nervous System over the Tissues of the Body.—In view of the conspicuous manner in which nervous impulses affect every-day life, we are perhaps apt to over-estimate the character and range of the influence exercised directly by the nervous system. From the early part of this century one way of regarding the body has been to consider it as made up of tissues grouped together in varying number and amount. Each tissue has its characteristic features under the microscope. We need not enter into the question as to which of the commonly recognised: tissues of the body are to be regarded as forming a class by them- selves and which are to be regarded as subdivisions of a class. The point I wish to lay stress on is that in any broad classi- fication not more than two tissues are known to be supplied with approximate completeness with efferent nerve-fibres. The striated muscular tissue, which forms, amongst other parts of the body, the muscles of the limbs and trunk, receives in all regions nerve-fibres from the brain or spinal cord. And the unstriated muscular tissue, which forms, amongst other parts of the body, the contractile part of the alimentary canal and of the blood-vessels, is in nearly, and possibly in all, regions similarly supplied. The glandular division of epithelial tissue in some parts responds promptly and strikingly to nervous impulses, but in some parts the response is feeble, and in others no nervous impulse has been shown to reach the tissue. The connective tissue which exists all over the body, and which in its varied forms of connective tissue proper—cartilage, bone, teeth, epithelioid cells—makes so considerable part of it, is in mam- mals, so far as we know, destitute of efferent nerve-fibres. The epidermic cells, which form a covering for the body, the ciliated cells, the reproductive cells, do not visibly respond to any nerve stimulus. And the myriads of blood corpuscles, which in different ways are in incessant action for the general welfare, are naturally out of range of nervous impulses. Ac- cording to our present state of knowledge, large portions of the organism live their own lives uninfluenced, except in- directly, by the storms and stresses of the central nervous system. No nervous impulse can pass to them to make them contract or to make them secrete, or to quicken or slacken their inherent activity. The nervous system can only influence them through the medium of some other tissue by changing the quantity or quality of the surrounding fluid. Regarding, then, the body from the point of view of the control exercised by the nervous system on the other con- stituents, we have first to recognise that this control is in considerable part indirect only, that the several tissues are in varying degree under direct control, and that different parts of 558 one ‘tissue may be influenced by the nervous system to different extents. Limitation in the Control of the Nervous System over the different Actevities of the Celt.—Even when nervous impulses can strikingly affect the vital activity of a tissue, their action is limited. They cannot modify the activity in all the various ways in which it is modified by the inherent nature of the tissue and the character of the surrounding fluid. Thus the sub- maxillary gland which pours saliva into the mouth is in life ceaselessly taking in oxygen and giving out carbonic acid; it does this without pouring forth any secretion. So far as we know, no nervous impulse can hasten or retard this customary life of the gland by a direct action upon it without producing other changes. The nervous system can only do this indirectly by modifying the blood supply. The nervous impulse which reaches the gland cells causes them to secrete, to take up fluid on one side and to pour it out on the other, and it does not, and so far as we know it cannot, confine its influence to those changes ordinarily going on in the gland cells. The essential effect of a nerve impulse appears to be ‘to modify the amount of energy set free as work ; usually it causes work to be done, as in the contraction of a muscle, or in the secretion of fluid by a gland ; sometimes it diminishes the work done, as in the cessa- tion of a heart-beat, or the decrease of contraction of a blood- vessel. Other changes often go on side by side with this setting free of energy as work, but there is no unimpeachable instance ; in which these other changes take place by themselves as the result of nervous excitation. Physiologists have sought for long years in all parts of the body for nerves—calorific or frigorific nerves—which cause simply an increase or decrease of the heat set free by a tissue; and for nerves—trophic nerves—which cause simply chemical changes in the tissue associated with a setting free of heat or not. Probable as the existence of such nerves seems to be, the search for them cannot, I think, be said to have been successful. Somatic or Voluntary Tissues.—When we look at the question of nervous control subjectively, and consider in our- selves what tissues are at our beck and call, we find that we have immediate and prompt governance over one tissue only, the one which, as we have already seen, is most universally supplied with efferent nerve-fibres—namely, the (fibrous) striated muscular tissue. The parts of the body composed of this muscular tissue we move, as we say, at will. We exercise a control over it that we cannot exercise over any other tissue. The tissue is supplied with a special system of nerves. In other vertebrates there is a tissue of similar microscopical characters, and having a similar system of nerves. And we can be certain that in all vertebrates the fibrous striated muscle and the nervous system belonging to it form a definite portion of the body which can be properly placed in a class apart from the other tissues of the body. The tissues in this class are spoken of as ‘‘somatic”’ tissues, or sometimes, in view of our own sensations, as ‘‘voluntary.’’ ‘‘ Voluntary” is not a word which physiologists care much to use in this context, because it readily gives rise to misconceptions. It will serve, however, if we bear in mind that the primary distinguishing characters of the system are microscopical, anatomical and developmental ; that other tissues than ‘‘ voluntary” can be put in action by the will, though in a different fashion ; and that ‘‘ voluntary”’ tissues are also put in action involuntarily. That is to say, the word will serve if we rob it of much of its ordinary meaning. The somatic or voluntary nervous system has in its essential features long been known. We may leave it and pass on to a more obscure field. Autonomic or Involuntary Tissues.—In putting on one side the voluntary system, you will notice that we have disposed of one only of the several tissues, differing microscopically from one another, which go to make up the various organs of the body. Of the rest some, as we have said, either do not receive nerve-fibres from the brain and spinal cord, or, if they do, practically nothing is known about them in our own class of vertebrates—the mammalia. These I shall say a word or two about later. For the present we must confine our attention to the tissues which are known to be supplied not too illiberally with nerve-fibres. These are unstriated muscle, and its allied cardiac muscle, and certain glands. Since the voluntary striated muscle has a nervous system of its own, it might be imag!ned that the unstriated tissue and the glandular tissue, differing as they do, would also have separate nervous systems. This, however, is not the case. The nervous supply of these two NO. 1562, VOL. 60] NATURE [OcTOBER 5, 1899 tissues have common features and belong to the same system. There is, unfortunately, no satisfactory term by which to designate it.- On the whole the term ‘‘ autonomic” seems to me best adapted for scientific use. But it is not of the first im- portance for our present purpose to insist upon a proper nomenclature, so that I think I shall not do much harm if I use the familiar ‘‘involuntary” for the unknown, or nearly unknown, ‘‘autonomic.” I need hardly point out how widespread are both the glandular and the unstriated muscular tissues. In man practi- cally the whole surface of the skin is supplied with sweat- glands, lachrymal glands lie hid behind the eye, small glands are thick in the respiratory tract from the nose to the smaller bronchial tubes, and glands stretch along the whole of the digestive tract. Most of these can be set in action by nerve- fibres. There are a number of others in which such action has not been shown, so that they do not concern us at present. Unstriated muscle forming, as it does, part of the walls of the arteries and veins, penetrates to every part of the body. It forms a large part of the coats of the stomach and intestines ; it is present in the spleen and in parts of the lymphatic vessels ; it is present in the iris and in other parts of the eye; it occurs in greater or less amount in different animals in the deeper layers of the skin. Consider some of the ways in which these tissues in the several organs or structures affect the working of the body. The heart contracts and supplies the driving force for the circulation of the blood ; the arteries contract less or more, here or there, and regulate the amount of the blood to each region; the digestive tract secretes solvent and disintegrating fluids in the food, churns it into pulp, absorbs some and rejects the rest ; the skin- glands pour out their tiny beads of perspiration, and so aid in regulating the temperature of the body ; the iris commands the aperture of the pupil and determines the amount of light falling on the retina; the ciliary muscle, by its varying contraction, brings about the focussing necessary for distinct vision. But the involuntary tissues do not confine themselves to actions of such flagrant utility as those just mentioned. The contraction of small bundles of unstriated muscles in the skin will cause the flesh to creep; other similar small muscles are attached to the hairs; ’tis these will make “Thy knotted and combinéd locks to part, And each particular hair to stand on end, Like quills upon the fretful porpentine.” The involuntary tissues, although not under the prompt and immediate control of the will, are under the control of the higher centres of the brain, They are particularly responsive to the emotions ; and in so far as we can call up emotions, we can play upon them at will. The ease with which nervous im- pulses pass along given tracts depends, amongst other things, upon use. And so it appears that our great-grandfathers wept and our great-grandmothers fainted with an ease which we should require assiduous practice to attain. Further, you may note that the contraction of involuntary muscle caused by an emotion may in its turn set up nervous im- pulses, which pass back to the brain and give rise to vague and curious feelings, feelings often lending themselves to effective literary expression :— ““Where our heart does but relent, his melts; where our eye pities, his bowells yearn.” I must ask your forgiveness for mentioning so many well- known facts in the sketch which I have just given of the in- voluntary tissues. But I hope it will take from you all excuse for not understanding the rest of what I have to say. The arrangement of the involuntary nervous system presents some peculiar characters. The most distinctive of these is that the nerves, after they leave the brain or spinal cord, do not run interruptedly to the periphery ; they end in nerve-cells, and the nerve-cells send off the fibres which run to the periphery. The most direct proof of this lies in the fact that a certain amount of nicotine prevents the central nervous system from having any influence on the peripheral structures—7.e. the line is some- where blocked ; it can be shown, speaking generally, that there is no block on either side of the ganglia, so that it must be in them. The actual point of attack of the nicotine appears to be the connections made by the central nerve-fibres with the peripheral nerve-cells. Thus all nerve-impulses, which pass from the brain or spinal cord to unstriated muscle or glandular tissue, pass through an intermediate station on their way. In OcToBER 5, 1899 | WM TORE 559 this, as in some other respects, the arrangement of the involun- tary nervous system is more complex than that of the voluntary nervous system ; in the latter the motor nerve-fibres run direct to the tissue and have no nerve-cells on their course. The nerve-cells which form the intermediate stations for the involun- tary nerve-fibres are grouped together into ganglia; and so we may call the nerve-fibres which run from the brain or spinal cord to the nerve-cells pre-ganglionic fibres, and the nerve- fibres which run from the ganglia to the peripheral tissues post- ganglionic nerve-fibres. \ The involuntary nervous system is divided into at least two subdivisions. The most extensive of these is what is called the sympathetic nervous System. The pre-ganglionic fibres of the sympathetic arise from a limited portion of the spinal cord. They arise from that part of the spinal cord which is in the region of the chest and the small of the back—z.e. roughly from the part which lies between the origin of the voluntary nerves for the arms and the origin of the voluntary nerves for the legs. The fibres given off by the ganglia of this system—z.e. the post- ganglionic fibres—run to the involuntary tissue in all parts of the body. The Cranialand Sacral Systems.—The second division of the involuntary nervous system consists of two parts: one part— the cranial—arises from the brain—z.e. above ‘the origin of the sympathetic ; the other—the sacral—arises from the end of the spinal cord—z.e. below the origin of the sympathetic. Each supplies a limited and different part af the involuntary tissue of the body, but both together supply a portion only of it. Taking the distribution broadly, they supply the muscular coats of the alimentary canal and certain structures connected develop- mentally with the anterior and posterior portions of it. They are especially connected with these terminal portions ; they send numerous nerve-fibres to them ; whereas they send but few to the intervening portion, and none at all to its blood-vessels. Thus parts of the involuntary tissue of the body receive a double supply of nerve-fibres, whilst parts receive a single supply only. Amongst the latter are all the involuntary tissues of the skin, the blood-vessels of the limbs and trunk, and of most of the viscera. The cranial and sacral divisions of the involuntary nervous system are considered by some observers to be simply portions of the sympathetic system separated from it by the development of the nerve-centres for the arms and for the legs. I may give one reason why I do not take this view. The middle portion of the spinal cord, which is the region that sends fibres to the sympathetic, always sends fibres toa given spot by more than one nerve, and usually by four or five. The fibres passing by the several spinal nerves never differ in the kind of effect they produce, but only in the degree of effect ; the difference is in quantity and never in quality. If, then, regions above and below were mere separated parts of this sympathetic region, we should expect that when one of these regions and the sympathetic region sent nerves to the same spot, the effect produced by both sets of nerves would be the same in kind, though it might differ in extent. But this is often not the case. Thus certain blood-vessels may receive nerve-fibres from four spinal nerves in the sympathetic region and from three spinal nerves in the sacral region; all the former cause contraction of the blood-vessels, all the latter cause dilation. And thus it seems to me probable that in the evolution of mammals the sympathetic nerves have developed at one time, and the cranial and sacral involuntary nerves have developed at another time. Inhibition.—A striking feature of the involuntary nervous system is its possession of nerve-fibres which, when excited, stop some action at the time going on. The most striking example is perhaps the cessation of the heart-beats brought about by excitation of the vagus nerve. Such nerve-fibres are called inhibitory nerve-fibres, and the stopping of the action is called inhibition. So far as has been definitely proved inhibitory nerve-fibres only run to involuntary muscle and to nerve-cells, and to these, so far as has been certainly shown, only in particular cases. It is true that when fear or other emotion causes the tongue to cleave to the roof of the mouth, there is a cessation of the customary fiow from certain glands, but this flow is itself the result of nervous impulses passing in ever rising and falling intensity from the central nerve-cells, and its cessation is due to inhibition of nerve-cells, and not to inhibition of glandular cells. The inhibition of nerve-cells has only been proved to take NO. 1562, VOL. 60] place in the central nervous system. When a group of nerve- cells of the central nervous system is engaged in sending out nervous impulses, other nervous impulses reaching them by way of other nerve-cells may diminish or stop their activity. The theory which is commonly advocated now to explain this inhib- ition makes the activity of the nerve-cells depend upon their receiving stimuli from the minute endings of other nerve-cells, and the cessation of the activity to depend upon these minute endings, either withdrawing themselves out of range, or having something interposed between them and the nerve-cells, so that the impulses can no longer pass. This theory I do not wish to discuss to-day ; it is sufficient to say that if it is true, the inhib- ition of nerve-cells is an entirely different process from that of the inhibition of involuntary muscle. Turning to the inhibition of involuntary muscle, there is a” source of confusion which we must first guard against. Nearly all the unstriated muscle in the body is kept in a state of greater or less tone, or contraction, by the central nervous system. A diminution or cessation of this contraction may then be caused by a diminution or cessation of the activity of the central nervous system. This cessation of contraction is, of course, not what we mean by an inhibition of the unstriated muscle. It is usually spoken of as an inhibition of the nervous centre. The inhibition we mean is that which is caused by stimulating the peripheral end of a nerve outside the spinal cord. I have said that this inhibition can only be obtained in certain cases, and it is not easy to find anything in common with regard to these cases. But on the whole it appears that the more a tissue is able to work by itself, the more likely it is to be under the control of inhibitory fibres. The heart, stomach and the intestines work when no longer connected with the central nervous system, and these are especially liable to inhibition. There has been a marked tendency amongst physiologists, in considering the question of inhibitory nerve-fibres, to take what may be called the view of the equal endowment of the tissues. Because some arteries have inhibitory nerve-fibres, therefore it is to be held as in the highest degree probable that all have. And many would go further and say that it is therefore in the highest degree probable that all unstriated muscle, and glands, and even the voluntary muscles, have such fibres. This view seems to me a mistaken one. There is hardly room for doubt that the motor fibres are supplied in most unequal measure to the unstriated muscle and glands of the body. There are veins in the body containing unstriated muscle, which show no visible contraction from any nerve stimulation, And there are a number of glands which no nerve—so far as we know— excites to secretion. Since in the course of the evolution of the organism, a universal development of motor fibres has not occurred, it is, I think, to be expected that the development of inhibitory fibres should be still less universal. For up to a certain point the results of inhibition can be obtained in most cases without inhibitory nerve-fibres, by a simple diminution in the impulses travelling down the motor fibres. The only, and the final, test is of course experiment. But not all experiments are decisive, and theory inevitably colours interpretation. This theory of the equal endowment of the tissues has, it seems to me, caused a number of quite inconclusive experiments to be accepted as offering satisfactory evidence for the existence of inhibitory nerve-fibres. i Passing from this question, we may consider briefly how far we can get on the way to understand what occurs during inhibition. The external characteristic feature of inhibition is that a certain state of activity ceases ; a muscle contracting at short intervals ceases to contract, or a muscle in a steady state of contraction loses this state. The tissue in either case becomes flabby. The activity of a tissue may obviously be due to its receiving some stimuli from the nervous system or to its own inherent qualities. In the former case, if the tissue were only active when receiving nervous impulses, we should naturally look to some interference with these impulses as being the cause of inhibition. The blood-vessels of the sub-maxillary gland appear to me to offer sufficiently clear evidence with regard to the inhibition of blood-vessels. The superior cervical ganglion is the local centre from which the nerve-fibres bringing about con- traction run to the blood-vessels of the gland. When this ganglion has been removed and the nerve-fibres from it have degenerated, the vessels receive no nervous impulses causing them to contract. But stimulation of the inhibitory nerve will still cause dilation—z.e. inhibition of the blood-vessels. The 560 NATURE [OcToBER 5, 1899 inhibition must then be due to a direct action on the tissue, and not to an interference with other nerve-impulses. The evidence with regard to the inhibition of the beat of the heart and of the tone or peristalsis of the alimentary canal is more complex, but there is good reason to believe that the contraction is in both cases due to their inherent qualities. And if this be granted, it follows that here also inhibition must be due to a direct action upon the tissue. The contraction of a muscle is due to a chemical change in it. In this chemical change some energy is set free as work—shown by the contraction of the muscle—and some as heat. It is con- ceivable that the nervous stimulus which causes inhibition should cause all the energy set free by the chemical change to take the form of heat. calorific nerve. the amount of carbonic acid given off to the blood. ments have been made as to the amount of carbonic acid given off to the blood by an inhibited tissue, but it appears very unlikely that the amount is increased, and we may take this view of the action of an inhibitory nerve as improbable. If the nervous impulse does not act in this way it must in some way stop the particular chemical change associated with contraction from taking place. It does not stop all chemical change, for blood passing through an inhibited tissue loses some of its oxygen. The simplest way for a nervous impulse to pre- The amount of chemical change is indicated by vent a particular chemical change is to induce a different one. We have seen that the tissues which are inhibited have a great tendency to contract of themselves—that is, they forin certain very unstable substances. not inhibited this tendency exists but little or not at all. In closely related tissues which are The Dar dae Fic. 1. proximate cause of inhibition might then be that the nervous stimulus causes certain molecules of the tissue to form more stable combinations. This need not be associated with any general assimilation ; it would simply make the muscle adopt for a time a mode of life more like that of other closely related muscle. Number of Relay Stations.—I have already mentioned that the nerve-fibres which pass from the central nervous system to the involuntary tissues do not run to it direct, but end in groups of nerve-cells or ganglia from which fresh nerve-fibres are given off. Now, in most cases, there are anatomically several ganglia on a nerve in its course from the spinal cord to the periphery. For example, the nerve-fibres which cause the hairs of a cat’s tail to stand on end, giving the tail the appearance of a bottle brush, leave the spinal cord in the lower part of the back, and enter a nerve-strand which is beaded with ganglia. They leave this strand near the root of the tail. Between the point where the nerve-fibres enter and the point where they leave the strand there are seven or eight ganglia. The fact offers us a problem of some difficulty. With how many of these ganglia are the nerve-fibres connected? Or, in other words, how many relay stations are there—eight or one, or some intermediate number ? Further, do all kinds of involuntary nerve-fibres in all parts of the body have the same number of relay stations, or do some have one, some two, some three, and so on? It would take too long to discuss this question here. But the experimental evidence is, I think, fairly decisive in favour of the simple view that the nerve-impulse passes through one relay station only. There is, however, evidence that the nerve-fibres which pass from the spinal cord branch, so that we may take the element by reduplication of which the involuntary nervous system is builtiup to be diagrammatically as in Fig. 1. NO. 1562, VOL. 60] In that case the inhibitory nerve would bea | No experi- Reflexes.—Another point of view is given by a comparison of the groups of nerve-cells of the peripheral ganglia with the groups of nerve-cells of the brain and spinal cord. The proper working of the body depends upon an agile response by the central nervous system to what is going on in the periphery. Now the peripheral ganglia are made up of nerve-cells and FIG: 2. nerve-fibres which differ less in general characters from some of the cells of the central nervous system than these differ from one another. The nerve-cells of the spinal cord can receive impulses from many groups of nerve-cells both near and remote ; they do not simply receive impulses from one quarter alone—say, the cortex of the cerebral hemispheres—but from many quarters, and notably direct from the periphery. Hence it has been supposed that the peripheral ganglia have similar wide connections, that they receive impulses direct from the periphery, that each is connected with other ganglia, and that impulses received from the periphery, or elsewhere, bring separate ganglia into coordinate action. And this view, which has been taken on general grounds, has been supported by microscopical observations. The evidence against this view is of two kinds. In the first place, it can be shown that in a number of individual cases the nerve-cells of one ganglion have no connection with the nerve- cells of another ganglion, so that anything like a universal scheme of connection is out of the question. And, secondly, it can be shown that whenever an action occurs, which might be referred to such connection, it is an action which is bound to occur in consequence of some other known arrangement, and that there- fore it is unnecessary to seek for a further cause. The evidence of the first kind we need not enter into; the evidence of the second kind we may hastily touch on. If we accept the conclusion stated above, that the pre-ganglionic nerve- fibres branch, and the branches run to different nerve-cells, it follows that a stimulus applied to one branch will stimulate a Sp.Cc number of nerve-cells ; this follows since a nerve-impulse set up in any part of a nerve travels over the whole of it. Thus actions, resembling reflex actions, will inevitably be obtained whenever nerve-fibres are stimulated which send branches to different ganglia. The mechanism in this case is confined to motor nerve-fibres and nerve-cells. The action, for lack of a con- OcToBER 5, 1899] venient term, was spoken of by Dr. Anderson and myself as a reflex action. It is perhaps better to call it a pseudo-reflex action. Regarded from the customary point of view, a pseudo-reflex differs widely from a reflex action. The one is brought about by stimulating an efferent or motor fibre, and the other by stimulating an afferent or sensory fibre. But suppose we compare them from another point of view. Fig. 2 is a diagrammatic representation of a pseudo-reflex. A nervous impulse passes up one branch a of a cell A, passes to another branch a’, so excites a cell B and its nerve-fibre 8. Fig. 4 is a diagrammatic representation of a simple true reflex in the voluntary muscle. A nervous impulse passes up one branch a@ of a cell A, passes to another branch a’, so excites a cell B and its nerve-fibre B. You see the two can be described in exactly the same terms, and both are reducible to the diagram of Fig 3. It is true that the cells A and B are not similarly situated in the two cases ; in the pseudo-reflex A is in the spinal cord, and B is outside it in a peripheral ganglion ; whereas in the true reflex A is outside the spinal cord, in a spinal ganglion, and B is inside the cord. But then no one has even suggested that the position of a nerve- cell determines whether an action in which it takes part is a reflexor no. So that this point is irrelevant. And so it might be urged that the one action has as good a title to be called a reflex as the other. I do not, however, wish to insist too much on this comparison. I am inclined to say, after Touch- stone, ‘* An ill-favoured thing, sir, but mine own.” If, as some think is the case, the spinal ganglion cell re- ceives the nerve-impulse conveyed by the peripheral nerve process, and modifies it before passing it on to the central process, this establishes a distinguishing character for the true reflex. It would be probably an axon plus dendron reflex, the pseudo-reflex being simply an axon reflex. The important known functional difference between the reflex and the pseudo-reflex is that in the former case the nerve-endings of the primarily affected nerve-fibre are specially differentiated for receiving nerve-impulses, and in the latter case these end- ings are specially differentiated for imparting nerve-impulses. And, on the whole, it is probable that the pseudo-reflex is not a normal part of the working of the body, but comes into play only as it were by accident. I do not, however, regard this as quite certain. The pseudo-reflex I have spoken of is caused by the ex- citation of nerve-fibres before they reach the ganglia—z.e. of pre-ganglionic fibres. But the fibres which are given off by the ganglia also branch, so that it appears inevitable that we should have in certain circumstances an action related to a reflex caused by a stimulation set up in one of these branches spreading to the rest—z.e. a spreading out of impulses in post- ganglionic fibres similar to that which occurs in pre-ganglionic fibres. Turning to the diagram, Fig. 1, a nervous impulse set up in one branch—possibly by a contraction of muscle-cells to which it runs—would spread to other branches and cause con- traction of the muscle-cells in connection with them. You will notice that this spreading out of impulses does not necessarily involve the stimulation of any nerve-cell ; it might perhaps be distinguished as zyradzatzon. It would, probably, be very local in action, unless there were overlapping of the districts supplied by the several nerve-cells, in which case a not incon- siderable spreading out of a local contraction might take place, giving rise to a peristaltic wave. It must be pointed out that it has been assumed that in the sympathetic nervous system an impulse cannot pass from a motor fibre through the nerve-cell from which the fibre arises and affect any other nerve-fibre or nerve-cell. There is good ground for this assumption, but the experimental evidence might certainly be more complete. To return to our main line of argument, we have good evi- dence that nervous impulses set up in one spot may affect regions more or less remote by a mechanism which does not involve the presence in the sympathetic system of special sensory nerve-cells with peripheral sensory nerve-endings. And so far as investigation has gone at present, I think that all the ap- parent reflex actions can be explained without reference to such sensory apparatus. And so I take the analogy of the peripheral ganglia with the central nervous system to be misleading, and consider that all the nerve-cells of which we have been speak- ing are motor nerve-cells, and that they all conform to the simple plan shown in Fig. 1. Thus the whole consists of a NO. 1562, VOL. 60] NATURE 561 duplication of one type; a cell in the spinal cord which branches, each branch ending ina single cell ; each of these cells sends off a nerve-fibre which branches, the branches ending in a group of involuntary muscle or gland cells. That I regard as the real working mechanism, but there are two reservations to make. All the tissues of the body may be looked upon as engaged in a lifelong process of carrying out experiments, and I am prepared to believe that there are in the body what may be spoken of as the residues of these natural physiological experiments, either the beginnings of ex- periments which have not succeeded, or the melancholy ends of those which once partially successful have failed later. Such possibly may be the nerve-cells which have been described in sympathetic ganglia as sending their nerve-fibres to other nerve-cells. Secondly, in this account I have not included the nerve-cells which exist in the wall of the alimentary canal, and the cells of Auerbach’s and Meissner’s plexuses. These ‘‘ enteric” nerve-cells belong, I hold, to a system different from that of the other peripheral nerve-cells. With regard to their con- nections I do not think anything can be said with certainty. Regeneratzon. Specific Nerve Energy.—One other problem presented by this involuntary system we may say a few words about. You know that when a nerve in the hand or arm is cut the nerve will in proper conditions grow again ; and the lost feeling and the lost power over the muscles will return. The recovery is brought about by the part of the nerve which is attached to the spinal cord growing along its old track and spreading out as before in the muscle, skin and other tissue. At any rate, that is the method for which there is most evi- dence. You may know also that when the nerve-fibres in the spinal cord are similarly injured, they do not recover function. Regeneration in the latter case implies that the nerve-fibres have to form fresh endings in connection with nerve-cells. If this were more difficult than the formation of nerve-endings in muscle and other non-nervous tissues, the difference which exists as regards recovery of function between the nerve-fibres of the limb and nerve-fibres of the spinal cord would be readily explainable. But recent experiments show that the nerve-fibres which run from the spinal cord to the peripheral ganglia—?.e. pre-ganglionic fibres—re-form with ease their con- nection with nerve-cells, so that we may probably seek in mechanical conditions for the reason of the absence of re- generation of the fibres in the spinal cord. Possibly some way may be found of improving the mechanical conditions, and so- obtaining regeneration. That question, however, we need not enter into. The regeneration of the pre-ganglionic nerves presents some very remarkable features. The nerve-fibres which end in a sympathetic ganglion are rarely, if ever, all of one kind—that is to say, they do not all produce the same effects. Thus, of those which run to the ganglion in the upper part of the neck, some cause the eyelids to move apart, some cause the pupil to dilate, some cause the face to become pale, some cause the glands of the mouth or skin to secrete, and others have other effects. These different kinds of nerve-fibres run, in large part at any rate, to different nerve-cells in the ganglion. Thereare in the ganglion several thousands of nerve-cells closely packed together. And it would seem hopeless for each kind of nerve-fibre as it grows again into the ganglion during regener- ation to find its proper kind of nerve-cell. Nevertheless, nearly all of them succeed in doing this. The nerve-fibres which normally cause separation of the eyelids, or dilatation of the- pupil, or pallor of the face, or secretion from the glands, pro- duce the same effects after several inches of their peripheral. ends have formed anew. The fact offers at first sight a striking proof of a specific difference between the different classes of nerve-fibres and different classes of nerve-cells. Through the matted mass formed by the delicate interlacing arms of the nerve-cells, the ingrowing fibres pursue their tortuous course, passing between and about hundreds of near relations until they find their im- mediate stock, whom they clasp with a spray of greeting tendrils and so come to rest. Absolute laws seem unfitted for a workaday world. For closer observation shows that the fibres have not always this marked preference for their ownstock. The nerve-fibres of the cervical sympathetic, the nerve I have spoken of above, do not often go astray, at any rate so far as is known. But they do sometimes ; thus it may happen that some nerve-fibres which 562 ought to find their home with nerve-cells governing the blood- vessels, take up with nerve-cells governing the dilator structures of the pupil. And if we turn to other nerves, greater aberrations are found. We have seen that the nerves running from the central nervous system to involuntary structures may be divided into two sets: the sympathetic nerves on the one hand, and the cranial and sacral nerves on the other. An important cranial nerve is the vagus ; it causes, when in action, cessation of the heart-beat, contraction of the cesophagus, contraction or inhi- bition of the stomach, and various other effects. It does not send nerve-fibres to any of those structures of the head which we have seen the sympathetic ganglion at the top of the neck —the superior cervical ganglion—so liberally supplies. And yet the vagus nerve, if it has a proper opportunity of growing into the superior cervical ganglion, will do so, and there establish connections with the nerve-cells. Thus the nerve which properly exercises control over certain viscera in the thorax and abdomen is capable of exercising control over structures in the head, such as the iris, the blood-vessels and the glands. The details of the process, with which I will not trouble you, do not afford any clear evidence that the nerve- fibres of the vagus pick and choose amongst the nerve-cells of the superior cervical ganglion ; the fibres appear rather to form their terminal branches around any kind of nerve-cell, so that, in fact, the action which the nerve-fibre will in future bring about depends, not on any intrinsic character of its own, but upon the nature of the action carried on by the nerve-cell. The nerve-cell may cause secretion from a gland, or contraction of a blood-vessel, or dilation of the pupil, or movement of hairs ; whichever action it causes, the nerve-fibre which joins it from the vagus nerve can cause for the future, and it can cause no other, In this case, then, we arrive at results which are hopelessly at variance with the view that the nerve-fibres and nerve-cells of the involuntary nervous system are divided into classes which are fundamentally different. In other words, that theory which is spoken of as the theory of specific nerve-energy does not apply here. But if this is so, how are we to account for the selective power shown by the sympathetic nerve-fibres which I have men- tioned earlier? That the different classes of nerve-fibres and nerve-cells with which we are dealing have not those deep and inherent differences which are required by the theory of specific nerve-energy is, it seems to me, certain. Nevertheless, there may be some differences of a comparatively superficial nature which suffice to explain the selective activity observed. We may suppose that a re-growing nerve-fibre will in favourable cir- cumstances join a nerve-cell the function of which is the same as that of its original cell, but that if there are hindrances in the way of this return to normal action, and if the conditions are favourable for joining a nerve-cell acting on some other tissue, why then it will join this. It is as if it had a preference, but did not care overmuch. We might perhaps express the facts by saying that there are different varieties of pre-ganglionic fibres, but no species. We have been speaking so far of the nerve-fibres which run from the brain and spinal cord to the peripheral nerve-cells. The nerve-fibres which run from the peripheral nerve-cells have also, there is reason to believe, a large measure of indifference as to the kind of work they perform. The limits of this in- difference have yet to be investigated. I have said earlier that in mammalia nerve-fibres are not known to run to connective-tissue cells or to epidermic cells. But in some lower vertebrates certain connective-tissue cells are under the control of the central nervous system. Thus in the frog the pigmented connective-tissue cells, which play a large part in determining the colour of the skin, can be made to con- tract or to rearrange their pigment granules—and so change the colour of the skin—by excitation of certain nerves. In all probability, the motor nerve-fibres to the pigment-cells belong to the same class as the nerve-fibres which run to the arteries and to the glands—z.e. they belong to the autonomic system. We have seen that unstriated muscle-cells and gland-cells in different parts of the body are by no means equally supplied with motor nerve-fibres, and it may be that in mammals there are certain connective-tissue cells which receive motor nerve- fibres. Further, if it is true, as it well may be, that nerve-fibres which run toa gland are capable in favourable conditions of making connections with a blood-vessel, it is not beyond hope NO. 1562, VOL. 60] LAL IE OW aga [OcToBER 5, 1899 that either kind of nerve-fibre may experimentally, by offering it favourable conditions, be induced to join connective-tissue cells. The factors which determine whether a particular tissue or part of a tissue is eventually supplied with nerve-endings, and the degree of development of these, are the factors which deter- mine evolution in general. In the individual, it is exercise of function which leads to the development of particular parts ; in the race, itis the utility of this development which leads to their preservation. And so it is conceivable that in some lower vertebrate at some time, the autonomic nervous system may have developed especially in connection with those tissues which appear in ourselves to be wholly unprovided with motor nerve- fibres. I am tempted, before ending, to make a slight digression. Those who have occasion to enter into the depths of what is oddly, if generously, called the literature of a scientific subject, alone know the difficulty of emerging with an unsoured dis- position. The multitudinous facts presented by each corner of nature form in large part the scientific man’s burden to-day, and restrict him more and more, willy-nilly, to a narrower and narrower specialism. But that is not the whole of his burden. Much that he is forced to read consists of records of defective experiments, confused statement of results, wearisome descrip- tion of detail, and unnecessarily protracted discussion of un- necessary hypotheses. The publication of such matter is a serious injury to the man of science; it absorbs the scanty funds of his libraries, and steals away his poor hours of leisure. Here I bring my remarks to a close. I have endeavoured to give as clearly as possible what seem to me to be the con- clusions which logically follow from certain data, but I would not have you believe that I regard them as representing more than the immediate point of view. As the wise man said : “‘Hardly do we guess aright at things that are upon earth, and with labour do we find the things that are before us.” AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. THE presidential addresses delivered before the Sections of Zoology and Botany of the American Association, by Profs. S. H. Gageand C. R. Barnes, respectively, are printed in Scéence of September 8. The subjects were ‘‘ The Importance and the Promise in the Study of Domestic Animals” and ‘* The Progress and Problems of Plant Physiology” and the subjoined extracts show some of the points dealt with. Abstracts of several other sectional addresses have already appeared in NATURE, p. 515. Prof. Gage described a few ways in which the study of do- mestic animals has thrown light on the problems confronting mankind in his social ideals, in preventive medicine, in physi- ology and hygiene, in embryology and comparative anatomy and in the doctrine of the evolution of organic forms. He showed that, with the higher forms at least, that is the forms most closely related to man, and with whose destiny his own eco- nomic, hygienic and social relations are most closely interwoven, the domestic animals have in the past and promise in the future to serve the best purpose because of the abundance of the material in quite widely separated groups of animals which long have been and still are under greatly differing conditions and surroundings ; and, finally, because this material is plentiful and under control, and thus may be studied throughout the entire life cycle. There has been and still is too great a tendency in biology to study forms remote and inaccessible. This is, perhaps, partly due to the fascination of the unknown and the distant, and the natural depreciation of what is at hand. But study of these supposedly generalised types has proved more or less disappointing. No forms now living are truly primitive and generalised throughout. They may be in parts, but in parts only. The stress of countless ages has compelled them to adjust themselves to their changing environment, to specialise in some directions so far that the clue through them to the truly primi- tive type is very much tangled or often wholly lost. Indeed, every group is in some features primitive. As any complete study requires much material at all stages the higher forms must be of the domesticated groups, or wild OcToBER 5, 1899] NATURE . 563 forms must be practically domesticated for the time being to supply the material. It may be objected, also, that in the investigation of domes- ticated forms sordid interests will play too prominent a part. No doubt to the true scientific man the study of zoology for its own sake, that is, for an insight into the fundamental laws of life, is a sufficient incentive and reward. Judging from the past, the study of the domestic animals in any other way than in a scientific spirit and by the scientific method will prove barren ; but studied in that spirit and by that method the result has always justified the effort, and has thrown as much, if not more, light upon biological problems than an equally exact study of a wild form. Therefore, while purely practical ends can never supply the inspiration to true scientific work, still surely no scientific man could feel anything but happiness that his work had in some ways added to the sum of human well-being. Perhaps no one has expressed so well the sympathy of a scientific man with his fellow-men as Pasteur in the preface to his work on the silkworm diseases : ‘* Although I devoted nearly five consecutive years to the laborious experimental researches which have affected my health, I am glad that undertook them. . . . The results which I have obtained are perhaps less brilliant than those which I might have anticipated from researches pursued in the field of pure science, but I have the satisfaction of having served my country in endeavouring, to the best of my ability, to discover a remedy for great misery. It is to the honour ofa scientific man that he values discoveries which at their birth can only obtain the esteem of his equals, far above those which at once conquer the favour of the crowd by the immediate utility of their ap- plication ; but in the presence of misfortune it is equally an honour to sacrifice everything in the endeavour to relieve it. Perhaps, also, I may have given young investigators the salutary example of lengthy labours bestowed upon a difficult and un- grateful subject.” In conclusion Prof. Gage summarised his address by saying : However necessary and desirable it may have been in the past that the main energy of zoologists should be employed in the description of new species and in the making of fragmentary ob- servations upon the habits, structure and embryology of a multitude of forms, I firmly believe that necessity or even de- sirability has long since passed away, and that for the advance- ment of zoological science the work of surpassing importance confronting us is the thorough investigation of a few forms from the ovum to youth, maturity and old age. And I also firmly believe that, whenever available, the greatest good to science, and thus to mankind, will result from a selection of domesticated forms for these thorough investigations. In the Section of Botany, Prof. Barnes discussed the chief features of plant physiology in which notable progress has been making during the last decade. The great advances in plant chemics and physics ; the progress in the investigation of causes of plant form : the widening ideas of the property of irritability ; the investigation of the social relations of plants, and the minute study of cellaction in spite of their diversity, have one great end in view. This is nothing less than the solution of the great problem— the fundamental problem—of plant physiology as of animal physi- ology, namely the constitution of living matter. Entrenched within the apparently impregnable fortress of molecular structure this secret lies hid. The attacks upon it from the direction of physical chemistry and physiological morphology, of irritability, of ecology and of cytology are the concentrating attacks of various divisions of an army upon a citadel some of whose outer defences have already been captured. The innumerable observations are devised along parallel lines of approach, and each division of the army is creeping closer and closer to the inner defences, which yet resist all attacks and hide the long- sought truth. One outer circle of defences yet remains untaken, and until that falls it would seem that there is little hope of capturing the inner citadel. More must be known of the constitution of dead sub- stances chemically related to the living ones. When the students of chemistry can put the physiologists into possession of the facts regarding dead proteids, the attacks will be renewed more directly, with greater vigour and greater hope of success. It is not possible to prove to-day that life and death are only a difference in the chemical and physical behaviour of certain compounds. It is safe to say that the future is likely to justify such an assertion. NO. 1562, VOL. 60] UNIVERSITY AND EDUCATIONAL INTELLIGENCE. CAMBRIDGE.—Eleven county and borough councils have arranged with the Board of Agricultural Studies to make grants for the maintenance of the new department of Agriculture established under the direction of Prof. Somerville. The first list of lectures issued by the Board includes some seventeen courses. In the valedictory address delivered by Dr. Hill on vacating’ the office of Vice-Chancellor, reference was ‘made to the fact that before the close of the academic year the contributions to the Benefaction Fund amounted to upwards of 50,000/. ; also that a commencement has been made with the new Geological Museum. The Museum will cost about 44,000/7., of which sum the fund raised as a memorial to Prof. Sedgwick will supply 27,0002. A TECHNICAL and mining college is to be established at Wigan at an estimated cost of 40,000/, THE Rev. J. F. Cross has been appointed professor of mathematics at St. John’s University, Winnipeg. Pror. A. McADIE has been appointed honorary lecturer on meteorology in connection with the Berkeley Astronomical Department of the University of California. Mr. THEODORE Morison has been appointed principal of the Aligarh Mahomedan College. The new principal, who is at present in this country, has been authorised to select two new professors to take out with him. Pror. WacstaFF will lecture on geometry at Gresham College from October 10 to 13, and the Rev. E. Ledger’s course of lectures on astronomy at the same institution will take place from November 14 to 17. THE degree of Doctor of Pharmacy has just been conferred by the University of Paris for the first time. The recipient is M. Lacourt, whose graduation thesis was entitled ‘‘ Historical, Chemical and Bacteriological Study of the Versailles Water.” THE fifteen universities of France together have a total of 27,080 students, of whom 12,059 belong to Paris. The total expenditure is 13,859,500 francs, so that the average cost of the education of each student is 511 francs (a trifle over 20/.). To meet this expense the universities have revenues amounting collectively to 2,093,700 francs; legacies, donations, &c., amount to 1,511,600 francs; therefore a deficit of 10,524,200 francs (equivalent to nearly 15/. for each student) has each year to be made up by the State. ArT the half-yearly meeting of the court of governors of Owens College, Manchester, held on Tuesday last, the following resolution was carried by a majority of two :—‘‘ That, subject to such limitations and conditions as the council may from time to time determine, and subject to the council being able to make satisfactory provision for a separate instruction in such cases as the council consider necessary, the court is of opinion that it would be desirable to admit women students to the course of study which would qualify them for medical degrees and practice.” ACCORDING to the Allahabad Pioneer M/az/, during the past year no fewer than 11,000 candidates presented themselves for the various examinations of the Madras University, and of these slightly over 4000 were successful. The fees paid by candidates amounted to nearly Rs. 1,87,000 ; while sundry items, including about Rs. 10,000 interest on Government securities, swelled the income of the University to a little over two lakhs of rupees, The total expenditure for the year came up to Rs. 1,80,000, of which sum Rs. 1,38,000 were absorbed by examiners’ fees. The Arts Examinations, as usual, yielded the greatest portion of the University income—the total fees realised from candidates amounted to over one and a half lakhs of rupees, while pay- ments to examiners came up to Rs. 90,000, The Law Examin- ations yielded a quarter of a lakh of rupees, while the examiners fees only amounted to slightly over half thissum. The Medical and Engineering Examinations, however, are conducted at a loss ; but, after balancing receipts and expenditure, the University realised a net profit during the past year of Rs. 10,000, without reckoning the Rs. 10,000 accruing as interest from Government securities. [OcTOBER 5, 1899 564 NATURE WE learn from a memorandum that has just reached us that the number of students who attended the City and Guilds of London Institute Central Technical College last session was 245. Of these 220 were following the Diploma Course, eighty- eight attending the First Year Course, seventy-eight the second, and fifty-seven the third. Twenty-five other students were either engaged in research work or were following a special course. During the past year the council has conferred the diploma of Fellowship of the City and Guilds of London Institute upon two of the past students: Mr. W. J. Pope and Mr. A. E. Childs. Siemens Medals were awarded to Mr. F. E. Whittle and Mr. F. C. Hounsfield. Mr. T. M. Lowry and Mr. E. C. Jee, were successful in gaining the D.Sc. degree of the University of London for research work done in the Chemical Department of the College. Twelve students of the College were successful in passing the intermediate B.Sc. examination of the London University. In addition to the students admitted on the results of the Matriculation examination, several others have been admitted to special courses of instruction, and the number in the College at the commencement of the new session will be about 260. Those in special courses number 20. As built the College was intended to accommodate only 200 students. To make adequate provision for Electrical Engineering, a large portion of the basement floor in the adjoining new build- ing of the School of Art Needlework is to be used. The suite of rooms now occupied by the Technological Examinations Department will also become available for teaching purposes, as “more extensive quarters are to be found for the Examinations Department in the new building. In connection with this institution, our readers may be referred to the address delivered to the students by Sir Andrew Noble, K.C.B., F.R.S., on ~ Tuesday last (see p. 551 of the present issue). WHEN the history of education in rural districts comes to be written, the school of science established by the united efforts of ~the Countess of Warwick and Prof. } Meldola, at Bigods, near Dun. mow, in Essex, will be given an important place in it. The claims of science to form a part of every national system of education are becoming more and more recognised in our cities, jbut the forward movement has not been much felt in rural districts, hence the school at Bigods is of the nature of an experiment, and much depends upon the success attained. The - curriculum followed in the school meets the requirements of modern education in a most efficient way. The school is a con- tinuation or secondary one in which the ordinary ‘‘ humani- tarian”’ subjects are by no means neglected, but are carried to higher stages. Modern languages are included, and grammar, geography and history find their places. But the noteworthy characteristic of the school lies in the fact that students devote , fifteen hours a week to science, which is not taught in the old- fashioned way, by means of books and blackboard and chalk, but by real work and by observations carried on by the pupils themselves in the laboratories and in the fields. The reasoning faculty is developed by scientific methods at the very commence- ment of the pupil’s education at the school ; and students who stay at Bigods for three or four years will have acquired knowledge which will be of the highest value in after life, whether they pass into an agricultural college or enter at once into rural or other industries. For the sake of British agriculture, it is to be hoped that parents in East Anglia will appreciate the efforts ‘being made at Bigods to provide a system of education which -will assist both individual and national progress. SOCIETIES AND ACADEMIES. Paris. Academy of Sciences, September 25.—M. Maurice Lévy in the chair.—Studies on trimethylene, by M. Berthelot. Pre- liminary experiments were made on the preparation of tri- methylene in the pure state, free from propylene, and the gas obtained, believed to be pure, was characterised by its slow re- action with bromine. Propy! alcohol dropped upon hot zinc chloride gives propylene mixed with hydrogen and propane, but almost free from trimethylene ; isopropyl alcohol behaves similarly, and the substitution of strong sulphuric acid for the zinc chloride does not result in the formation of any trimethyl- ene.—On the Neomylodon, by M. Albert Gaudry. An account of the discovery of fossil remains in a cave in Terra del Fuego by Dr. Otto Nordenskjéid, the chief being the NO. 1562, VOL. 60] skin of a large animal resembling the Mylodon, and which has been named Neomylodon by M. Ameghino.— An account of the ceremony organised at Como to celebrate the discovery of the galvanic battery by Volta.—Observations of the sun made at the Observatory of Lyons with the 16 cm. Brunner equatorial during the first quarter of 1899, by M. J. Guillaume. The results are expressed in three tables giving the number of spots, their distribution in latitude, and the distribution in latitude of the facule.—A comparison of the times obtained for the contacts of partial eclipses of the sun by direct observation and by measurements of the lengths of common chord, by M. Ch. André.—On fixed transformation points, .by M. H. Le Chatelier —On the diurnal variation of atmospheric elec- tricity, by M. A. B. Chauveau. From the results of observ- ations made at the summit of the Eifel Tower, it is found that the true law of variation is given by a simple oscil- lation with a maximum in the day time, and a very con- stant minimum at 4 to § a.m. The more complicated curve obtained by observations in an ordinary building are probably due to the influence of water vapour. —On a particular mode of reproduction of appendices of insects in course of regeneration after artificial section, by M. Edmond Bordage.— On the lateral cephalic organs in Glomeris, by M. N. de Zograf.—Some phenomena of cellular disorganisation, by M. Vital Boulet. The asmotic pressure in the cells of a leaf severed from the plant and left in the same water as that in which the original plant was growing was found to regularly increase from 2°2 on the first day to over 670 on the twenty-second day.—On the formation of secreting canals in the seeds of certain species of Garcinia and Allanblackia, by M. Edouard Heckel. CONTENTS. Berthelot’s Agricultural Chemistry. By R. W. .. 541 Our Book Shelf :— ‘Bird Life in an Arctic Spring ; the Diaries of Dan Meinertzhagen and R. P. Hornby.”"—R. L. . . . 542 Abbott and Key: ‘‘ Progressive Lessons in Science” 543 Rauh: ‘De la Methode dans la Payee des Sentiments.”—A, E. T. . 543 Lebon : ‘‘ Histoire Abrégée de l’Astronomie ARS e545 Letters to the Editor :— The Intake of Carbon Dioxide—a Correction.— Dr. Horace: BrownwbeRsS. .'1.) 2s aces ay Geological Time.—Rev. O. Fisher . . 544 The Terrestrial Gegenschein.—Prof. S. Newcomb 544 The Cause of Undercurrents.—Admiral S. Makaroff 544 Movement of Sea-Gulls with a Coming Change of Weather.—W. F. Sinclair . . 545 On the Use of the Fahrenheit Scale for Observations on Sea Temperatures.—William S. Bruce . . 545 Cave Shelters and the Aborigines of Tasmania.—H. Ling Roth . . 545 The Darjeeling Disaster.—Prof, de Milne, LESRIS 545 Lectures at the Royal Victoria Hall. —Dr. W. oh Russell, F{RiS3 ie 68 545 H Vole.—James Dallas . ae S46 | The Investigation of the Malarial Parasite... . 546 MrvPercy'S: Pilcher sere... 2 eeueeeemyaO Notes. (J//lustrated.) . . Se PE Sees ak 8 Gy. (S) Our Astronomical Column :— Astronomical Occurrences in October . ..... . 55E Comet. H-Giacobini@eeeemeneniiis| « - - Smee mm Sim Mwo New Variable}Starsimpmmey ce)... te oe 5 5u The Melbourne Observatory . . wis Bieeuuth u SG The Best Education for Engineers, ‘By Sir Andrew Noble; K.C-B_ RIS tamemaion:. .. . centuEcmismSeS SIL The British Association :— Section H.—Anthropology.—Opening Address by C. H. Read, President of the Section . 554 Section I. — Physiology. (Ldlustrated. )—Opening Ad- dress by J. N. Langley, F.R.S., President of the Section ~ . 557 American Association for ‘the Advancement ‘of Science .. Se e502) University and Educational ‘Intelligence oi gaecl ef 08) | Societies and Academiecsiearmerem: «: » . slmeureimenisi 504: | INeAT U RE 565 THURSDAY, OCTOBER 12, 1899. VERWORN’S “GENERAL PHYSIOLOGY.” General Physiology. An Outline of the Science of Life. By Prof. Max Verworn. Translated from the second German edition by Dr. Frederic S. Lee. Pp. xvi + 615. (London: Macmillan and Co., Ltd., 1899.) E cordially welcome the appearance of an English translation of this well-known book. The first (German) edition appeared in 1894, and was noticed at some length in this journal (vol. li. p. 529). The in erest which it excited is testified to by the practical fact that a second edition in German was called for in 1897, while translations into English, Italian and Russian have also appeared. The second edition differs from the first only in detail. The general plan remains the same, though, as the author remarks in the preface, the more important results of the very large number of researches in the physiology of the cell which have appeared during the last few years have been added. The scope of the book is “an attempt to treat general physiology as general cell-physiology,” and thus to out- line a field in which the various branches of special physiology might unite. The author is at some pains to define the cell as the unit of organised living matter— the smallest part which can maintain an independent existence ; it is the “elementary organism.” Having described this unit, and discussed its structure and chemical and physical constitution and the way in which the substance of which it is composed differs from non- living substance, the author proceeds to a consideration of the phenomena which are manifested by cells in general. He is thus led to a discussion, firstly, of the internal phenomena of life in their most general aspect— of change of substance or metabolism, of change of form, and of change of energy ; and, secondly, of the external relations of living matter, of food, of effects of temper- ature, &c., of stimuli, of the origin of life on the earth, and of the process of dying. Lastly, he returns to a consideration of the nature of the material of the cell, and seeks there an explanation of these internal and ex- ternal phenomena. These inquiries are sufficiently wide ; but the author, not content with them, includes an in- teresting history of physiological research, in which he rightly endeavours to justify his own standpoint by an appeal to the development of the science ; and a discus- sion, in true Ercles vein, of the relation of physiological research to metaphysics in which, among -other things, the investigator is invited to “ get rid of the error of the existence of a physical world outside the mind”! Those who have made acquaintance with Prof. Ver- worn’s views in other and earlier publications, as, for instance, in papers published in the AZonzst¢ (cf NATURE, li. p. 58), will not be surprised to learn that the tone of the book is somewhat aggressive. He has set himself the task of recalling physiologists from the barren field of “one-sided specialisation,” whatever that may mean, to a renewed consideration of the ultimate problems of life. He is impatient with the “ impotence of the physi- ology of to-day in the presence of the simplest vital NO. 1563, VOL. 60] processes.” The outworks are down, why do the workers stay prying into the ruins when they should press on to attack the central citadel, the cell, wherein the simple secrets of these simplest of processes are hidden ? No fault can be found with the purpose which is out- lined here, but unfortunately the reader's sympathies are apt to be lessened by a lack of restraint and reticence in the advocacy. There is an unpleasant tone of special pleading running through the pages, which inevitably raises the suspicion that the author’s outlook is perhaps not so broad as he would have us believe. A good wine needs no bush, and the virtues of an endeavour to bring together all that is known of the general properties of living matter suffer when heralded by an impeachment of the past achievements of physi- ology which is phrased so as to convey the idea that the nature of the processes which constitute life has not been touched on. In point of fact, the knowledge gained, amongst other things, of the internal respiration of muscle, of the automatic phasic activity of the cardiac and other tissues (due, by the way, mainly to the work of Gaskell, and not to that of Engelmann, as the author states), and of the special processes of storage and discharge in glandular organs, has led to a first ap- proximate conception of the character of the changes, both in matter and energy, which waits for further development, not upon the labour of biologists, but upon that of workers in the domain of molecular physics. It is possible that the central idea of the book—the assertion of the identity of general physiology with cell physiology—is founded upon a misconception, and we are inclined to doubt whether any special virtue is likely in the future to flow from the study of the cell. If the cells in question form part of tissues or organs, then the methods are the methods which have been employed in the past. The study of the cardiac muscle cell is the study of the heart, of the secreting cell that of the gland which holds it, and so on. Practically, as one learns by perusing Prof. Verworn’s pages, what is really new in his method is confined to the exaltation of the importance of the study of the cell when it is an independent individual, such as one finds in the members of the Protozoa. In this field he has himself laboured with no small measure of success. The phenomena exhibited by free-living cells are unquestionably of surpassing interest, but, un- fortunately, the study of the relatively diffuse activities which they manifest must be of secondary importance, seeing that the facts which are gleaned can only be in- terpreted by the aid of that insight into the finer anatomy of function which springs from a study of the highly specialised organs of the higher types where the activities of living matter are, as it were, analysed for us. This is not the only drawback. There is another, and perhaps more serious one, which the author nowhere stops to discuss. It lies in the difficulty which exists when minute forms are used for experiment in deciding how far a given result is a true physiological reaction to a stimulus, and how far it is a purely mechanical effect. For in- stance, under the heading of galvanotaxis, and in the section dealing with the general effect of electrical stimuli, a description is given of the way in which animalculz become grouped round one of the poles, while individuals suffer actual alteration in shape under the influence of a BB 566 IN ATMO TE: [OcronER 12, 1899 constant current. But, as Faraday was the first to show, small particles of any kind are driven to one or other pole when suspended in fluid through which a current is passed, and a rod of jelly suffers compression at one end and expansion at the other under the mechanical stresses produced by the passage of a current. The general tone of the book is inspired by an im- patience with the laggard pace of knowledge—the “foster-child of silence and slow time,” if one may wrest a phrase of Keats from its setting—which prompts the taunt that the physiology of to-day is impotent in face of the simplest vital processes. Unfortunately, it is not controlled by a true feeling for the relation of the know- ledge of living matter to the progress of the general knowledge of matter. The tools with which the attempt to fashion a dynamical explanation of the phenomena of life must be made are themselves still in the making. It is barely ten years since what was practically the new science of molecular physics was founded at the meeting- place of chemistry and physics by the labours of Guld- berg and Waage, Arrhenius, van ’t Hoff, Gibbs, Ostwald and others. On the growth of this science the biologist must wait, and, though the advances which it has made are prodigious, they are concerned wholly with the crystalloid type of matter—they have not yet embraced ‘the colloid type which is the physical basis of life. The completeness of our ignorance of the latter type is manifested with almost dramatic force when one finds all that is known of colloidal matter lying in the compass of a page or two of a text-book such as that of Ostwald or of Nernst, whereas the account of the crystalloid type stretches to many hundreds! Reproaches and hasty generalisations are equally out of place in the face of ‘this colossal ignorance of the elements of the problem ; and one feels the practical wisdom of physiological workers in devoting themselves to what may be called the anatomy of function—that is, the interpretation of organ and tissue activities in terms of the fundamental properties of living matter, rather than in kicking against the barriers which the general state of knowledge opposes to the translation of these fundamental properties into terms of matter and motion. The same lack of a sense of the historical position of biology caused Bunge to drift into vitalism, which at any rate has the merit of recognising the difficulties which stand in the way of a dynamical explanation of meta- bolism, irritability, and the recurrent cyclic character of the phenomena of life. Prof. Verworn, however, is impelled to the opposite extreme—a materialism, often rash, which leads him to a disastrous quest for “simple explanations,” in which his knowledge too frequently becomes wire-drawn to the breaking point. The “mechanical explanation” which he offers of the “so-called” selection of food will serve as an instance. A cell bathed bya nutrient fluid such as, e.g., an epithelial cell absorbing material from the lumen of the intestine, is likened to a crystal growing in its mother liquor. Like its analogue, it withdraws only special substances from the common nutrient fluid, “as is evident from the fact that gland, muscle and cartilage cells produce wholly different and characteristic sub- stances.” Hence the conclusion that the selection of food is only a special manifestation of chemical affinity, NO. 1563, VOL. 60] and that “it is an absolutely necessary consequence of the fact that the living substance of every cell possesses its own specific composition and its own characteristic metabolism.” So in place of the healthy recognition of a difficulty we are offered a cumbrous platitude and a leap in the dark ! The simple explanation which is offered of the fact “which must otherwise appear very wonderful” (sic), that among the innumerable swarm of spermatozoa cast into the sea, every spectes finds its proper ovum, also deserves mention. It “is explained very simply by the further fact that every species of spermatozoon is chemio- tactic to the specific substances that characterise the ovum of the corresponding species.” The robe of modesty is more fitting than the gown of counsel for explanations like these ! In other cases the haste for simple explanations leads to a mode of treatment of problems of acknowledged difficulty which intensifies the obscurity. Thus some space is devoted to urging that there is no distinction between the motor impulse er the electric current in their action upon, for instance, muscle fibres and that re- lation between motor nerve cell and muscle fibres which, when it is broken by severance of the connecting nerve, causes degeneration of the latter. This view is dis- tinctly opposed to the results of recent work upon muscular tone, and upon the effects of section of the roots of spinal nerves which tend to emphasise the dis- tinction between the calling out of special activity by special nervous impulses and the fact that many highly specialised cells are dependent for their continued well- being, even for their capacity to respond to stimuli, upon their functional continuity with other and totally dis- similar cells. We are ignorant of the nature of the latter relation, though it may well be one of simple dynamical equilibrium rather than one dependent upon the passage of nervous impulses. But Prof. Verworn starts in a panic from this unsolved problem. He sees in it a piece of the old mysticism of the vitalists, and, in order to compass a simple explanation, trophic relations are grouped with the action of electric and chemical stimuli and of food into one class which lacks both order and form. In spite of these defects in general tone, the pages of the book furnish abundant justification for the success which it has already attained. The point of view which the author has adopted has led him to bring together a body of facts, many of them little known, in a manner which cannot fail to be stimulating and suggestive to both physiologists and morphologists. Many gems of thought, too, are to be found, especially in the later chapters. The sections on the directive effects of unilateral stimulation, chemiotaxis, barotaxis, &c., are singularly interesting, and so too is the conclusion which is drawn from the facts, namely, a_ general application of the principle of the specific energy of sense-substances. “All living substance possesses specific energy in Miiller’s sense : with certain limits wholly different stimuli call forth in the same form of living substance the same phenomena, while, conversely, the same stimulus in dif- ferent forms produces an effect wholly different and characteristic for every form.” OcToBER 12, 1899] The treatment of the dynamics of movement as a polar change in the resultant of the anabolic and kat- abolic processes in the cell, or “ biotonus,” as the author calls their algebraical sum, is equally illuminating, as are also parts of the mechanics of cell metabolism. The pages dealing with actual facts, which after all make up by far the greater part of the book, possess an enticing feeling of freshness and novelty which is born of the fact that the author’s special studies have lain out of the beaten track. For this and for the intrinsic interest of the facts themselves we feel grateful to him, and we heartily wish success to the English edition. The translation bears abundant evidence of the care which Prof. Lee must have lavished upon it. It is a monument of clearness throughout. W. B. Harpy. OUR BOOK SHELF. Living Pictures. By H. V. Hopwood. Pp. xii+275. (London: The Oftician and Photographic Trades Review, 1899.) THIS is a very interesting review of the gradual evolution of the various instruments which have been invented for the portrayal of objects in motion, from the earliest times to the present day. The work may be divided into two parts, of which the first, including Chapters 1.-111. (pp. I- 109) deals with the more distinctly historical aspect of the subject, while the remaining chapters (iv.-vil.) are devoted to a very minute description of all the important machines in present use. Chapters i. and ii., on the ‘“‘ Persistence of Vision,” &c., contain a lucid account of the principles governing the phenomenon ofa succession of different views of the same object giving the impression of the object being in motion. In this part all the instruments, whether as toys or scien- tific apparatus, are described in the order of their inven- tion, beginning with the simple colour tops and thauma- trope put forward as early as 1826. The host of im- provements from this time up to about 1878 were attempts to remedy the difficulty of so small a percentage of light passing the two slits at first used for the inter- mittent view. This section concludes with descriptions of the modern mutoscope and viviscope. Chapter iii. (pp. 43-109) commences with the invention of “ chronophotography,” and gives a complete descrip- tion of the more important of the inventions brought out from 1865-1895. The mechanical details in connection with the alternate exposure and movement of the sensi- tive surface receive special attention, the difficulty of following these being greatly lessened by the numerous illustrations accompanying the text. Chapter iv. is devoted to present-day apparatus, and all the machines which have appeared before the public re- ceive ample notice, in most cases accompanied by a woodcut showing the internal arrangements. Chapters v. and vi. deal with the processes adopted in making the films, their exposure, development, printing, &c., and also give ample practical instructions for exhibiting the pictures in the lantern. At the end of the volume two most useful appendices are given. The first is a “Chronological Digest of British Patents,” giving a short vészmé of all specifica- tions taken out in connection with living pictures from the time of Fox Talbot (1851) to the end of December 1808. The second appendix is an annotated bibliography of all publications (British and foreign) from 1825 to the present time, which bear on the subject. The numerous illustrations (242), which are well chosen and very clearly printed, ‘render the following of the NO. 1563, VOL. 60] NATURE 567 necessarily somewhat technical matter exceedingly interesting even to the non-expert. The book will be welcomed by many to whom the methods of cinemato- graphy are a mystery, as by its aid any one even strange to the subject may easily understand the working of any of the machines in past or present use. Tables and Data. By W. W. F. Pullen. Scientific Publishing Company, 1899.) IN these eighty-seven pages Mr. Pullen brings together tables and data which will be found very serviceable in engineering laboratory work and in the solution of class problems and exercises in mechanical engineering. Points perhaps of special mention are that the general steam table is carried up to 300 lbs. per square inch ; the diagram for determining the dryness of steam with the- throttling calorimeter is plotted on a large scale, and the melting points of various substances has been revised by’ Sir William Roberts-Austen. For facility of reference the British and metric measures are placed side by side. The remaining portion of the book is devoted to mathe- matical notes on mensuration, geometry, trigonometry,, &c., with a synopsis of mathematical data. At the end are added a few extra pages, some of which are blank, while on others are printed diagrams of millimetre paper,. for the insertion of any additional curves the student may wish to insert. Not only engineering students, but others should find the contents of this book a useful laboratory vade-mecum. (Manchester : LETTERS TO THE EDITOR. The Editor does not hold himself responsible for opinions ex- pressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for this or any other part of NATURE. No notice zs taken of anonymous communications. | Halo Round a Shadow. IN your issue of this week Prof. S. Newcomb draws attention to the halo which an observer often sees round the shadow of his own head when the ground on which the shadow falls is covered with vegetation or any obstructions which can them- selves cast shadows. In a letter to NATURE in 1878 or 1879 (I have not the reference by me) I mentioned this phenomenon, giving the: same explanation as your recent correspondent, and adding that the angular width of the halo was settled by the ratio of the mean diameter of the obstructions to their distance from their own shadows. The halo (or spot of light, if the observer is too far off for his own shadow to show) can be seen very well when the ground is covered with heather or bracken whose twigs and leaves are small compared to their height above the ground. 3 Victoria Street, S.W., October 6. A. MALLOCK. The Skull of Hatteria. Ir may be worth while to draw the attention of naturalists to an omission in the figures of the skull of that archaic reptile, the Tuatara, that occur in two recent text-books of somewhat wide circulation, viz. Parker and Haswell’s ‘‘ Text-Book of Zoology” and Reynolds’s ‘‘The Vertebrate Skeleton.” These figures are either copied or redrawn from Zittel’s figure published in his well-known work on Paleontology. This figure appears to have been drawn from an imperfect specimen, as the ‘‘trans- verse” (or transpalatine) bone is omitted in the ventral view ; it is afparently represented in the dorsal view, however, though there isno index line in the original, The bone, though of considerable size, very readily drops out of a thoroughly macerated skull, from which the figure was no doubt drawn. There is really no excuse for our English authors borrowing the figure from a German book in this instance, for Dr. Giinther’s. picture of the skull published in the Phz/, Trans. vol. clxvii.,. is perfectly accurate, except in regard to nomenclature of some: of the bones, while Zittel’s is most indistinct. Dunedin, N.Z., August 30. W. BLAXLAND BENHAM. 568 INO: [OcToBER 12, 1899 THE BEST EDUCATION FOR AN ENGINEER} AN admirable address, well thought out, well delivered, and received with bursts of applause, which were so enthusiastic that they sounded like volleys of musketry. We are still in the early days of the history of technical education, and such deliberate expression of opinion by those who are connected with the engineering industry are much needed on the subject of the early training of the engineer; and when the speaker 1s Sir Andrew Noble, in whose works 30,000 gain their living, and when, in addition, he says what he really thinks, and does not merely confine himself to complimentary remarks about the College in which he is speaking, his address cannot fail to command close attention. On two important occasions captains of industry, when referring to the early education of those who afterwards go to the City and Guilds Technical Colleges, have en- Jarged on the value ofa classical training—Mr. Alexander Siemens in 1892, and now Sir Andrew Noble. Now, why is this? A considerable proportion of those who have made their mark undoubtedly received a classical education, but one asks, Was it the classical education that made them famous, or was it their great natural ability, and consequent success, that made the reputation of classical education? Oris there some other and deeper reason for this advocacy of the study of the language and literature of the peoples who, near the beginning of our era, occupied a small portion of the earth as we now know it? Not certainly the argument so frequently urged— urged even by Sir Andrew Noble in this address—that a student of science should study classics to better understand tke meaning of scientific terms. This will teach him that “geometry” means “land surveying,” and leave him disappointed that six books of Euclid do not enable him to measure an irregularly shaped field ; his Greek will tell him that a “logarithm” is a “ pro- portion number,” but a book of them will still be Greek to him. That it is a microphoné that is used in sending a message to a téléphoné will provoke a laugh from the man in the street, and if to a knowledge of classical grammar the student of science adds that of his own language, he will realise that one reason why it is so difficult to obtain a “reliable” measuring instrument is because such a thing is impossible, for the verb “to rely” must be followed by the preposition “on.” No! such a utilitarian argument in favour of classical study is rather a confession of weakness. Nor—as is so often alleged—is a classical study of importance because it facilitates the learning of modern languages. For many are the Dutch, the Poles and the Russians who talk with exasperating volubility in one’s own language, wherever one may have been born, but who know less Greek and Latin than an Eton boy whose linguistic powers are as insular as himself. A study of the classics and a public school education are frequently regarded as synonymous, and so the ad- vantages of the one are confounded with the advantages of the other. At the present time, when so much attention is devoted in secondary and technical schools to matter rather than to #zanmer, when the aim apparently is to turn out scientific encyclopedias rather than fairly well- informed people with cultivated manners, the following opinion expressed by Sir Andrew Noble should be taken to heart by every engineering student : ‘*Speaking as an employer of labour, I should say that we find a pleasant speech and manner, tact in dealing with others, and some power of organisation of the utmost value; and it is precisely those qualities which a boy acquires, or ought to acquire, in his Zafer years at a public school. Without such qualities even the highest scientific attainments will never make 1Tnaugural Address of the Session 1899-1900 of the City and Guilds Central Technical College, given at the College, Exhibition Road, bv Sir Andrew Noble, K.C.B., F.R.S., on Tuesday, October 3. NO. 1563, VOL. 60] a captain of industry, and in selecting candidates for appoint- ments the man of business distinctly prefers a youth who has had the benefit of some years at a good school.” But this polish, we urge, might equally well be acquired were the study of Japanese or the production and use of the electric current, or the action of mechanical forces, substituted by a though¢ful teacher in a public school for that of Greek and Latin. For that cultivation, which we all value so highly, is not produced by the association of a lad with dead writers of exceptional ability, but with living lads of his own standing, coming, like himself, from homes where refinement and right feeling pervade, and all, like himself, bent on preserving a tradition which, though sometimes foolish, sometimes rough or even brutal, still tends on the whole towards civilisation. It is not so much the study as the /zfe of a public school boy that is so valuable in forming his character. But if that be the case, is Sir Andrew justified in deducing the following conclusion ? ““My own impression with regard to early education is that, as a sharpener of the young intellect, and as a mental discipline, it would be difficult to improve upon the curriculum which is now in force at our public schools, and which, in the main, has been in force for so many centuries.” The curriculum of a public school is, we think, not exempt from the rule that what man has devised can always be improved. A classical education, the staple of the public school curriculum, has undoubtedly the great advantage that some of the greatest thinkers in the past spent the early part of their lives in receiving it, and the latter portion in giving it to others. It is, therefore, the particular form of training that has been carefully thought out, and its development is the result of long years of trial and error. Further, it possesses another advantage, the value of which does not seem to have received the recognition it deserves, and this is that when the merest dullard is puzzling out some passage with the aid of dictionary and grammar, he is really engaged in a small way on precisely the same kind of work that enchants the greatest scientific investigator, viz. finding out for himself something that he wants to know. Now this by no means characterises the work of all the students in a well-fitted modern laboratory. Not a few, following the instructions, spend hours taking read- ings of instruments and tabulating the results, but fail to find out what is the meaning of these results, or even what is the object of the experiment itself. They have, in fact, been laboriously grinding at the handle of the barrel organ, but have been mentally deaf to the tune that it played. Heartily then do we join with Sir Andrew Noble in deprecating training of this kind—whatever it may be called—and agree with him that even when all technical study is postponed until after school and college life :— “Those men who, with fair abilities, have received a really good education, have been taught to use their minds, and who, by contact with other students, have acquired habits of appli- cation, amply make up for their late start by the power of mind and grip that they bring to their work.” But can these qualities, we ask, only be acquired by confining a boy’s attention to the study of words and ideas, and by excluding all study of nature and things? Sir Andrew himself states :— *“TIn nine cases out of ten, I should say, any knowledge acquired by a boy before he is sixteen can have but a slight intrinsic value. Up to that age, it is not what he learns that we have to look at, but Zow he learns ; it is the habit of dis- cipline, of mental application, of power in attacking a subject, that are so valuable ; not, generally, any definite piece of know- ledge he may have gained.” Now surely “the habit of discipline, of mental ap- plication, of power in attacking a subject ” is exactly what OcTOBER 12, 1899] IGA TURE 569 can be learnt from a proper study of science, and, so far from any knowledge acquired by a boy before he is sixteen having but a slight intrinsic value, is it not a fact that all knowledge requiring mechanical dexterity, such as reading, writing, arithmetic, riding, swimming, talking foreign languages, playing a musical instrument, &c., can be far better acquired before the age of sixteen than later, and are not all these examples of knowledge possessing intrinsic value ? We are, however, quite at one with Sir Andrew in thinking that “the age at which a boy should seriously begin any special studies, with a view to fit him technically for the profession he may have decided to follow, should not be earlier than seventeen or eighteen.” But should not a sharp distinction be drawn between learning technology and acquiring the elementary prin- ciples of science? His warning that the zest for your life’s work may be weakened by embarking on it too early certainly furnishes a potent, probably the most im- portant, reason why lads who intend to become engineers should wait until they are eighteen, or at any rate seven- teen, years old before they commence their professional education; for then, as is said in the address, they will be **fresh and keen when others, who have been hammering away at semi-technical work from early boyhood, have become stale and are less vigorous.” For the same reason also, time devoted by a lad to learning off strings of scientific facts would be misspent, but not so, we think, would time given by-even a child to the acquisition of scientific habits of thought. We do not defer teaching a lad the principles of morality until he is seventeen or eighteen for fear he should become tired of living a moral life, why then should the risk that a lad might weary of leading an intellectual one frighten us into excluding the principles of science from a good education? In the address, “science, mechanical drawing, and such like” are classed together as things that may with advantage be omitted from the training of a lad before entering Elswick, provided he has had a good educa- tion. But can an education of the present day be termed “good” which lacks a training in those mental qualities which are classed under the head of scientific ? Great stress was laid by Sir Andrew Noble on the value of the knowledge which a person has gained for himself. He cited the results which “dauntless energy, untiring industry and patient search after truth” had achieved for Lord Armstrong, Watt, Stephenson and Faraday, but only as a proof “that a special technical education is not an absolute necessity.” Do not the lives of these men, however, teach us much more than this, viz. that the particular system of education, classical, mathematical, scientific, artistic or technical— in fact, any system of education ever invented—is less than nothing in enabling a man to rise to the top in comparison with the determination to succeed and the brains to do it ? The reason why certain branches of industry have al- most abandoned this country, and why new branches that have been developed abroad have hardly taken root with us, is a topic deeply interesting to the manufacturer, but generally rather distasteful to the student, since he would prefer to be told that everything was done better, more cheaply and more expeditiously in his own country than in any other. Sir Andrew Noble, however, made even the part of his address which dealt with this subject appeal strongly to his audience, and for a remedy he thought that it was “*to theoretic and technical knowledge that we must chiefly look. Consider, as an illustration, electricity in the service of NO. 1563, VOL. 60] man. Think of its innumerable applications, and of the number of hands dependent upon its industries. But for one man capable of designing or improving these powerful machines or delicate instruments, there are a thousand ready and able to carry out their designs. But it is the former who are the salt of the earth, and those who have the management of large concerns know well how to value them.” His patriotic statement (for it is true patriotism to help your own countrymen to learn the truth even if it be dis- tasteful) that the success of our German competitors was not due “to their putting on the market inferior goods specially got up to imitate those of a superior class,” but “to the far greater opportunities of technical study which are afforded in Germany,” was as bold as we believe it to be true. For we were recently informed by an English manufacturer that certain things manufactured in Eng- land are now being stamped “ Made in Germany,” in order to obtain a readier sale for then: in our own country. But in addition to greater facilities being needed in Great Britain for the study of the applications of science to industry, greater belief in the value of such study is wanted, not only on the part of the English manufacturer, but also on the part of the English student. “You younger men,” said Sir Andrew, “‘must do your part by seeking to avail yourselves to the uttermost of any such opportunities provided,” and it might be added that the reason why that future “important commercial rival, Japan, is developing its manufacturing powers with an energy that is as remarkable as it is unexampled” is because even thirty years ago its young students absorbed with eagerness and rapt attention every scrap of scientific teaching which they could obtain. And they did so partiy for their own personal benefit, but far more because each one felt that on his own exertions depended the fame and future of his mother country. W: E. A. RESEARCH WORK AND THE OPENING OF THE MEDICAL SCHOOLS. ie one sense at least, viz. his intellectual life, the medical student, natural enough in other respects, seems somewhat at variance with nature ; his intellectual spring occurs simultaneously with nature’s autumn. Brown October sees him change the abstractness of the class-room for the concreteness of the laboratory. Further, each successive autumn, after a period of summer hibernation, marks the advent of some change in his studies. The fully fledged doctor, too, whose daily round obliterates all distinction between term time and vacation, becomes infected in October with a revival of intellectuality, and whets his appetite by an attendance at the inaugural address delivered at his school, where he gets new knowledge or old dished-up afresh, and becomes generally imbued with the spirit of the time. This year at least the medical student will not be able to lay any shortcomings which may occur during the ensuing academical year to the charge of insufficient or inadequate advice at its onset. At both the London and provincial schools the inaugural addresses, with regard to depth of meaning and also attractive eloquence, have left little to be desired. In a short article such as the present it would be im- possible to adequately reproduce, even in the most abridged form, the various “motifs” pervading the speeches delivered. One, however, constantly recurring, may be somewhat enlarged upon. Here and there and everywhere in the inaugural addresses we find the position of research to medicine and the medical pro- fession cropping up. Occasionally this subject is mooted in the grossly material form, when, for instance, Sir James Crichton Brown frankly told his hearers at Manchester that although 70,0007. was an adequate sum so far 579 Manchester must be prepared to put its hand in its well- lined pocket for an equal amount to keep pace with science, which is now so mobile and so expensive. Dr. Clifford Allbutt delivered an address at St. Thomas’s, which mostly consisted of a strictly logical defence of theory and abstract learning. Those who read carefully Dr. Allbutt’s address will find more in it even than this. The apostles of empiricism, to whom the almighty fact is alone of importance, are the worst enemies of what may collectively be termed medical research. Their bourgeois utilitarianism prevents them from appreciating or forwarding any branch of inquiry connected with the medical sciences which does not immediately result in something of use. Research to them is the quintessence of an abstractitude. This mental attitude of a part of the profession, which fortunately is getting less and less, finds its expression in the position adopted by the influential public and lay committees. It is somewhat anomalous—at any rate, it appears so—that astute financiers, practical men ac- customed to weigh the chances of ultimate dividends in the most complicated concerns, should so discount patho- logical and pharmacological research. It must be known to them that a large proportion of the drugs they take, ; and the curative remedies they employ, are made in Germany, and that thousands of pounds are spent annually on German products of this class which might perfectly well be produced at home. Those of them who wander so far from the Stock Exchange as St. Dunstan’s Hill will find there a whole colony of German firms which supply these articles. A public which will wait for years for dividends so far as concerns South African securities, which will fill up readily the gaps in a Cape to Cairo railway scheme, although this at present can only be done by a somewhat lively imagination, is in- clined to push and accelerate the scientific worker, and expect maximum results in minimum time. The success of the German manufacturer in products such as ther- apeutic sera and synthetic drugs is simply due to the fact that the German capitalist has waited for his divi- dends which he is now getting. Apart from the stand- point of mere commerce, it is somewhat galling to know that a crude product like coal-tar is at present exported from this country, and re-imported worked up in the shape of dye-stuffs and drugs. To work one must have a workshop ; a palace one does not need. ‘This forms another great difficulty with regard to medical research in London. The authorities at the London hospitals rightly regard the patients as having the first charge upon the space and accom- modation at their command. Space in London, especially so far as concerns the older foundations—such, for in- stance, as St. Bartholomew’s and Guy’s—is necessarily very valuable. This subject formed the keynote of some of the speeches at the old students’ annual dinner at St. Bartholomew’s. The Great Hall was full of old Bartholomew’s men, who, under the chairmanship of Dr. Lauder Brunton and the secretaryship of Mr. Bruce Clarke, met to inaugurate the new academic year. Dr, Lauder Brunton, in a short but effective speech, proudly stated that the hospital, so far as its essentially medical aspect went, left nothing to be desired ; quite so much, however, could not be said for the laboratory accommodation. Sir Norman Lockyer, whose opinion upon the subject of experimental technique ought certainly to be final, also deplored this want of laboratory space in so old and famous a medical school. Many difficulties special to medical research were discussed by Sir Norman, and research in this branch of knowledge was compared to research in the physical sciences. One of the difficulties was the question of time. The worker in the fields of the medical sciences must solve his problems often at once. He must be an opportunist. Stars and planets remained more or less the same, but this was not NO. 1563, VOL. 60] NATURE [OcroBER 12, 1899 so with disease. Pressure from without, according to Hunter, causes hypertrophy or overgrowth, pressure from within atrophy or waste. If the pharmacological labor- atory at St. Bartholomew’s is not in a condition of healthy overgrowth, it is certainly not because pressure from without is wanting, for, according to Dr. Brunton, its confines have been narrowed down to some fourteen square feet. It was reassuring to be informed by the treasurer, Sir Trevor Lawrence, that arrangements were on foot which would ensure more ample accommodation to laboratory workers at Bartholomew’s. The London Hospital was fortunate in securing the presence of Dr. Haffkine, who made an excellent and humorous speech. The St. George’s students were addressed by Dr. Howship Dickinson upon “ Medicine Old and New.” Dr. Mitchell Bruce, at Charing Cross, took the “Outlook of Medicine” as the subject of his address. This was, he said, at the present time hopeful, since the scientific method was being pursued in every department of medicine. In laying stress upon the special difficulties of the time, one is perhaps rather apt to forget the causative origin of all the inaugural addresses, viz. the medical student himself. He comes in ample numbers, a sufficient testimony to the healthiness of the profession he aspires to join, from year to year, sometimes partially prepared by the universities, sometimes raw from school, to struggle with those life-long difficulties of the healing art, compared to which even examinations count as nothing. For five years, now, he must suffer many things of divers examiners, and finally emerge to meet the great problem of his life—the human indi- vidual, both healthy and diseased. Exact knowledge in the sense of physical exactitude will probably be denied to as yet many generations of medical students, even concerning the main problems of disease, and in spite of the progress that, thanks mostly to careful and continual laboratory work, often of an apparently abstract nature, has during the last century been made, our know- ledge even now serves often merely to illuminate our ignorance, and however optimistic our hopes for the future we are forced to admit that— A thousand things are hidden still, And not a hundred known. Ey aVicuele DARK LIGHTNING FLASHES. [° there such a phenomenon as dark lightning? This is a question that has often been raised, and as yet no satisfactory answer has been given. If dark flashes do really occur, then they should probably be both seen and photographed, and the former, one would think, would be the more simple way of recording them. A difficulty, however, here arises, for if we assume that both dark and bright flashes occur during a thunderstorm, then we must be careful not to mistake retina-fatigue dark flashes for actual dark flashes if they exist. Lord Kelvin (NATURE, vol. lx. p. 341) has lately pointed out how, during a recent storm, he was able to confirm the existence of these apparent dark flashes; and in a more recent number of this journal (vol. lx. p. 391) I published some observations corroborating the same view. It must be pointed out, however, that, although such observations indicate that the majority of dark flashes seen may be attributed to the cause of fatigue of the retina, it does not necessarily follow that dark flashes do not actually occur. Eye observations, therefore, do not help us as yet to give a satisfactory answer to this question. Let us turn now to photography, and see what evi- dence we can gather from photographs of flashes taken during thunderstorms. In dealing with this mode of recording flashes, we are OcrosER 12, 1899] NATURE 571 again confronted with many difficulties, for the action of light on the sensitive film is capable of giving us both bright and dark images, although the object photographed is bright. We have, therefore, to contend with reversals, double reversals, &c., and many as yet unknown factors. There is one point, however, that stands out foremost, and that is that the photographic plate has recorded many times dark as well as bright flashes ; but whether the dark flashes are due simply to some action relative to the sensitive film, or are actual images of real dark flashes, is the very question that has so recently been revived. What we really are greatly in need of is more data, and when a sufficient number of photographs of all kinds of lightning has been collected, more light will be thrown on this subject. Up to the present time, as each curious photograph of dark lightning was published, suggested theories as to the cause of the peculiarity of the flash have been by no means few in number, so that now the number of hypotheses equals, if not exceeds, that of the photographs examined. In a very interesting article in this journal (vol. xlii. p. 15i), which is an extract from a lecture on “Electrical Phenomena in Nature,” delivered by Mr. Shelford Bidwell at the London Institution, the so-called ““dark flash” is referred to in these terms. “ It occasionally happens that, on developing a photo- graphic plate which has been exposed during a thunder- storm, the image of a lightning flash comes out black instead of white. . . . There is no need to discuss the several ingenious hypotheses which were suggested in explanation of the anomaly ; it is sufficient to say that the mystery was completely cleared upa few months ago by the experiments of Mr. Clayden.” As I have no reference to Mr. Clayden’s experiments at hand, I will quote from the above-mentioned abstract a brief summary of his hypothesis as described by the same writer. “Tf the lens of the camera be covered the moment after a flash has occurred the developed image will always come out bright, feebly or strongly, according to circumstances. If, however, the plate be exposed after a flash has acted upon it, either to the continued action of a feeble diffused light or to the powerful glare arising from one or more subsequent flashes, then on develop- ment the image of the original flash will probably come out black. The effect is therefore not a meteorological or physical one, but purely chemical. It can be obtained, not only with a lightning flash, but also with a machine spark, or even with an ordinary flame. It is merely necessary that the plate should be exposed to the action of a certain amount of light after it has received the impression and before development.” At the present time Mr. Clayden’s explanation may be looked upon as the most reasonable working hypothesis for future use. There is one crucial test which can be tried, which would settle once and for all its value. Un- fortunately, so far as I am aware, this test has not yet been made, and I propose (and I hope others will as well) under the next suitable conditions to make the attempt. It is simply this. Take two cameras, say A and B, and orient them both in the same direction towards the point where the same flashes will come in both fields of view. Expose A for say fifteen minutes to record all the flashes that occur during that interval (some of these on development should be é7zgh7, some dark). EExpose B for one flash only, preferably the first bright one which occurs during the exposure of | A; this should develop é7zght. Compare the same flash on both negatives ; that in A should be dark, that in B bright. If this be not the case, then I think the hypothesis breaks down. Perhaps this experiment may not be so easy to perform as it at first appears, for the difficulty lies in being able to catch one strong NO. 1563, VOL. 60] flash without exposing the plate to any light from other flashes which illuminate the sky, but are not in the field of view themselves. Several attempts by numerous observers would probably give us the information required. With the object of firstly contributing data towards the interpretation of this curious and interesting phenomenon as recorded by the sensitive; film, I give here some illustrations from absolutely funtouched negatives of Fic. Germany, in 1893. lightning flashes. All these reproductions are reduced about one-third. I may perhaps preface my descriptions of the photo- graphs by the remark that, having always taken a great interest In procuring lightning flashes by the aid of the camera, I have never, until this year, been fortunate enough in securing records of dark flashes. I have always previously exposed my plates or films for periods. of fifteen minutes or more, depending on the strength and nearness of the storm. This fact at first suggested to me the idea that dark flashes might after all be real, but Fic. 2.—Showing dark (a and B) and bright (c and p) flashes photographed at Westgate-on-Sea on August 5, 1899. restricted to certain kinds of storms, the special pecu- liarities of which I cannot state. Fig. 1 is a type of several negatives I have secured previous to this year, and although the exposure was. twenty-five minutes in length, an examination of the negative shows absolutely no trace of any dark flash. The photograph, which was taken at Gottingen in North Germany, Is interesting on account of the fine flash (a) which is traversing the air in a nearly horizontal direction and without any branches or ramifications. In the right- t.—Lightning flashes taken during a thunderstorm at Gdttingen, *y 572 NATURE [OcTOBER 12, 1899 hand corner will be noticed numerous flashes from clouds a great distance away. I will now describe three of the four photographs I secured during the storm that passed over Westgate- on-Sea, Thanet, during the night of August 5 of this | year (see letter, NATURE, vol. Ix. p. 391) ; all four show Fic. 3 —Showing bright (p and p) and dark (a and c) flashes photographed at Westgate-on-Sea, on August s, 1899. dark as well as bright flashes. The camera employed was one of those excellent and handy little 5 x 4 day- light folding Kodaks, and the exposure in each case was fifteen minutes. The storm, I may add, passed roughly from S.E. towards N.W., and my camera was placed on awindow-sill facing due north. W.J, LOCKYER d 1999 Fic. 4.—Showing bright (sn and c) and dark (a) flashes photograph=2d at Westgate-on-Sea, on August 5, 1899. Fi flashes, and ~ “5 showing the north-western sky, displays several the most prominent of which are C and D bright \ and B dark. The bright flashes have no rami- fice cane while the dark distinct flash A has several dark. It may be that B is only a large ramification of A, but it is difficult to sz Ly. NO. 1563, VOL. 60] | | Fig. 3. The northern sky as here shown displays four | prominent flashes, A and c dark and B and D bright. |B, as will be noticed, appears to take a very circuitous path, which resembles very closely that illustrated ina previous number of NATURE (vol. xlil. p. 152), and which | was a reproduction from a photograph taken on June 6, 1889, by Mr. Rose at Cambridge. | The last, and, I think, absolutely unique photograph of Fic -Enlargement of dark flash a in Fig. 4. a dark flash, is illustrated in Fig. 4. The negative was exposed when the storm was perhaps just a little north of my position (camera pointing due north). The two most prominent flashes are those marked A and B. B is the ordinary bright flash with numerous bright ramifications, while A is also equally, if not more, strong but dark with dark ramifications. An enlargement of this flash is shown in Fig. 5. Most interesting, OcTOBER 12, 1899} IVA TURE 5a3 however, is the veversa/, which extends nearly the whole way up the centre—that is, the dark flash has along its centre a bright core. It is this very photograph which made me cast doubt on the hypothesis suggested by Mr. Clayden, for both a very strong flash can be recorded very dark (with a reversal), and also a weak flash (see Fig. 2, B). If the reader refers to an interesting article on “Lightning,” by Mr. Jeremy Broome, that appeared in the January number of the Strand Magazine in 1897, there will be found a reproduction of a photograph taken at Cambridge by Messrs. Valentine Blanchard and Lunn, showing a éright flash with a dark reversal down the centre, the exact opposite to the flash recorded above. It may be remarked that a reversal is perfectly distinct from a double flash, many of which have been recorded. Another flash of interest and peculiarity is that marked | c. This flash is quite distinct from B, but unlike all the other bright flashes of about the same intensity, which are clear and sharply defined, this one is occasionally split up along its path into two parts, and the flash on both sides throughout its whole length is bounded with dark borders. Both the original negative and a silver print show this peculiarity distinctly, but unfortunately | the dark borders are lost in the reproduction. I find that this peculiarity about a flash has been photographed before, but apparently not noticed. If the reader will refer to an old number of Avow/edge (vol. xvill. p. 224), he will find a reproduction of a lightning flash taken by Mr. George Primavesi at Tooting. This flash is far more intense than that on my negative, and the dark borders are more developed. The main stream is devoid of ramifications: the exposure lasted for only one second. To sum up, then, the different appearances of the | lightning flashes recorded in these photographs, and others of which I possess either photographs or re- productions ; we have the following various kinds :— Main stream. eeminca | Peyersal | Source of information. Bright None | Lie LGN - | Bright Fig. 4, B e Dark } NATURE, vol. Ix. - 423 ac _ None Dark Strand Magazine, Tan. 1897, p. 41 7 Bright Dark ? Aa | Dark Dark ? Dark None Fig. 3, A a beDark , . | Fig: 2, a | Bright ? a5 None Bright 2 oe Dark | Bright Fig. 4,.A » Bright | Bright ? under which category it should be placed. Now in attempting to explain the cause of dark light- ning I employed Mr. Clayden’s idea as a_ working hypothesis, but I can find no reference to any illustra- tions of the experiments he carried out. Mr. Shelford Bidwell, however (NATURE, vol. xlii. p. 153), describes and illustrates one out of a series of €xperiments he made, and this shows dark and bright flashes made artificially, but the flashes are simply dark or bright, with no other peculiarities. Further, in a letter which appeared ina very recent issue of this journal, Mr. F. H. Glew mentions that he also has made several experiments with re- gard to the Clayden effect. The illustration which NO. 1563, VOL. 60] accompanies his account of these investigations (the Photographic Journal, vol. xxiii. No.7, p. 179) shows, like Mr. Bidwell’s, no more than simple dark and bright flashes. I may here mention that the method described by me further on was not very dissimilar to that employed by Mr. Glew, although I was unaware until quite recently of the publication of his to which reference has just been made. Now the point most interesting to me was, Could one artificially produce on one plate or film exact types of dark and bright flashes as shown in the above illustrations ; that is, flashes which are dark with d7zght cores and bright with dark borders? No photographs of sparks produced artificially have, so far as I know, displayed any of these peculiarities. I will simply describe one experiment that I made, with this object in view, in the laboratory of the Solar Physics Observatory, Kensington. To produce the spark I employed a 10-inch Apps’ coil, with a pint jar in circuit, fed by two cells of four volts each, the sparking distance being two inches. The camera was a small 5 x 4 by Herr Winkel of Gottingen, fitted with a Zeiss objective. Although it was made only fic. 6.—Showing three series of sparks taker on one plate against a white background. During the passage of the sparks at c, the background was artificially illuminated, for the use of glass plates, by a simple device Eastman’s film could be employed. Films, I may mention, eliminate all chances of halation. The method of procedure was as follows :— In a darkened room I first of all made an exposure on a single (2-inch) spark against a bright (white card- board) background. On development this bright flash came out naturally drzght. : : I next inserted a new film and repeated the same experiment; except that I did not remove the film or develop it immediately. Covering up the lens carefully, I moved the poles in a vertical plane so that the next: spark should fall on a different part of the film, and made a second exposure on two sparks. Again covering the lens, and moving the poles a little in the same » direction, I exposed the film once more to a series of four sparks, but while I allowed the sparks to pass I illuminated the cardboard background by burning one inch of magnesium ribbon at a distance of two feet. It may be mentioned that the poles only appear on the negative in their respective positions when the back- ground is artificially illuminated. Fig 6 shows the results obtained. A is the first spark, B the two sparks after the first movement of the poles, and C the last four flashes when the background was artificially illuminated. 574 NATURE [OcroseR 12, 1899 A close examination of the figure shows that, not only do we get types of simple bright flashes, but we obtain dark flashes with bright cores and bright flashes with dark boundaries. Now A (Fig. 6) is exactly similar in type to the dark flash in Fig. 4, A, while the two bright flashes in C corre- spond also to the bright flashes in Fig. 6. The peculiar flash at C (Fig. 4) is an exact counter- part of D in Fig. 5. This experiment leads me to conclude, therefore, that Mr. Clayden’s hypothesis is entirely corroborated, and explains very satisfactorily the types of flashes illustrated in the above reproductions from photographs. In studying Fig. 4 in the light of these results, we can form a good idea of the order of appearance of the flashes. That marked A was undoubtedly the first to occur (if the plate had been immediately developed, it would have come out bright); then the flash B made its appearance, and, being so intense, illuminated the neighbouring region round A that the image of A on the film was affected chemically. C was probably next in order of occurrence, but, being more distant and therefore fainter, did not have any effect on A or B. C, however, was affected by subsequent flashes, which were not bright enough to illuminate the field to alter the intense bright flash B in any way, but which were capable of adding dark borders toits sides, The above order of appearance is to a great extent corroborated by the apparent distances and in- tensities of the flashes. There seems very little doubt now that, by varying the intensities of the sparks and that of the illuminated background, one can produce any combination of bright and dark flashes. A glance again at Fig. 6 will show that the appearance of a flash depends simply on the magnitude and presence or absence of the core. The following table sums up the six chief types of flashes that probably can be obtained: the reader will notice that there is a complete cycle commencing and termin- ating with a dark flash. 1. Dark flash, no core. Os »» 95 small bright core. {ens flash, broad bright core ; : or, \ Bright flash, narrow dark borders. Bright flash, 720 dark borders. small dark core. ye & This would represent an ordinary weak reversal. { Bright flash, broad dark core; | This would represent an 6. or, ordinary strong reversal. | Dark flash, narrow bright borders. Dark flash, 0 bright borders ; or, same as No. I above. ” ” 7. In the above list photographs have actually been obtained of all the types of flashes that came under the headings 1-5. I have examined all my zegatives to search for the type No. 6, with the result that I have not found a representation of this kind of flash. It may be remarked that the types 1-3 are produced as a direct consequence of the Clayden effect, and should therefore only appear on plates which contain more than one flash. The other types, which depend simply on the intensity of the flash, should be obtained when even only one flash appears on a plate.s We thus see that actual photographs of lightning bear out what we should expect from laboratory experiments, and we must therefore answer in the negative the ques- tion asked in the first line of this article. Dark lightning flashes therefore do not exist in nature, but their appearances on photographs are due to some chemical action which takes place in the gelatine film. In closing this article I wish to draw attention to the great interest which is attached to this most fascinating subject. Every one who has a camera can help in the NO. 1563, VOL. 60] elucidation of the several points to be studied, and most probably bring new facts to light. The photography of lightning flashes during the night is an easy subject, for one has simply to turn the camera towards the dark sky, and the lightning does all the exposing itself. Unfortu- nately it is not every one who is aware of this fact, and I know of two instances of amateurs who exposed plates during the same storm and at the same place where I obtained the above pictures, but they tried te catch the Jlashes by using instantaneous shutters. Whether they obtained any positive results I do not know, but one could make a very fair guess. _ Ifany readers of this article would be willing to exchange interesting unmounted lightning photographs obtained by them for copies of any of the above illustrations from the original negatives, the writer would esteem it a favour. (Address: 16 Penywern Road, South Kensing- ton, S.W.) This request suggests to me that it would be important for the furtherance and development of this subject, if there were some recognised ‘“ Central-Stelle” to which copies of all such photographs could be sent. Those studying the subject would not then be so much hampered in searching for references to accounts of original observations and reproductions, if a fairly com- plete collection of copies from original negatives were made accessible. WILLIAM J. S. LOCKYER. NOTES, Pror. A. GRAY, F.R.S., Professor of Physics in the Uni- versity College of North Wales, has been appointed to succeed Lord Kelvin in the chair of Natural Philosophy in the University of Glasgow, and will at once commence his new duties. THE Harveian Oration will be delivered at the Royal College of Physicians, London, on October 18, by Dr. G. Vivian Poore, and the Bradshaw Lecture on November 2, by Dr. A. Foxwell. Major RONALD Ross and other members of the Liverpool Malaria Expedition have returned to this country very well satisfied with their labours. On the advice of the expedition the authorities at Sierra Leone decided to use every means to exterminate the malaria-spreading mosquito. Major Ross is of opinion that the white population is not careful enough, and that the houses are badly constructed, and compare unfavourably with the residences of white people in India, which are constructed on plans that give the inhabitants every chance of health, despite the tropical climate. He attaches great importance to this question of the construction and situation of the houses. Dr. Fielding Ould, a member of the expedition, has remained behind - to consult with the medical officers on the coast respecting measures to be taken for the extermination of the malarial ~ mosquito in the neighbourhood of the principal towns. During the investigation one member of the expedition, Mr. Austin, suffered from malaria ; he became infected through sleeping one night without the protection of mosquito curtains. Drs. CALMETTE AND SALEMBENI, who were sent out by the Pasteur Institute as a commission to study and combat the plague in Oporto, have returned to Paris more than satisfied, it is said, with the success attending their efforts with the anti- plague serum. Dr. Calmette is of opinion that the Portuguese might easily free themselves from plague if they would rigor- ously carry out the measures which have been recommended to them, and in particular if they would inoculate all the in- habitants of suspected quarters. This, however, they appear unwilling to do. ACCORDING to the Civil and Military Gazette, Lahore, the Indian Government has under its consideration a somewhat com- prehensive scheme for the establishment of research laboratories OcrToBER 12, 1899] in various parts of India, and the appointment of health officers to the charge of them. The present laboratory at Muktesar will, it is understood, be further developed, and the staff in- creased, the establishment becoming the central research labor- atory for India, and health officers will be appointed to the charge of laboratories at Calcutta, Madras, Bombay, Agra and Lahore, the new department of bacteriology being ordinarily manned by officers of the Indian Medical Service. Dr. Cart PETERS has, it is stated by Reuter, left Portuguese territory and crossed into Mashonaland. Part of his expedition has, however, been left in the neighbourhood of the ancient ruins re-discovered by him near the Zambesi. Dr. Peters’ intention is reported to be the establishment of a permanent station on the Inyanga Highlands, and to explore from that point the whole of Mashonaland from north to south. The explorer claims to have discovered mica, saltpetre and diamonds ina district practically uninhabited, at an altitude of 8000 feet, and, he believes, easily capable of cultivation, As the rainy season is now setting in Dr. Peters will, after exploring some districts on the Pungwe River, proceed to Beira 22 route for England. WE regret to have to record'the death, at the age of fifty- eight, of Mr. John Donaldson, a partner of the engineering firm of Thornycroft, which took place last week. Mr. Donaldson had much to do with the introduction of fast torpedo boats into the British Navy, and was a great believer in his firm’s water- tube boiler. He was a member of the Institution of Civil Engineers, the Institution of Naval Architects and the Institu- tion of Mechanical Engineers. Science announces the death, at*the age of eighty-four, of Chief Justice C. P. Daly, who for many years took a deep interest in scientific matters, particularly in the branches of geography and botany. Mr. Daly was for thirty-six years president of the American Geographical Society, and was largely instrumental in founding the Society’s extensive library, and in securing the endowment of its new building. He also rendered good service to the Botanical Garden of New York, and:was one of its managers. MONUMENTS in memory of Siemens and Krupp will be un- veiled at Charlottenburg on the 19th inst,, the occasion being the centenary of the Technical Institute of that town. Ir having been decided by a number of friends and pupils of the late Dr. Friedel to place a bust and enlarged photograph of him in the hall of the Sorbonne, a circular asking for subscrip- tions has been distributed. The bust will be the work of M. Uitain, who executed that of Schutzenberger, and is estimated to cost 3000 francs. Subscriptions should be sent to M. Chason, at the Laboratory of Organic Chemistry, Faculty of Science, the Sorbonne. THE highest observatory in Germany is now completed. It is situated on the Schnee Koppe, the highest summit of the Silesian Mountains, at an elevation of 5216 feet. It will be managed as an institution of the Prussian State. Mr. W. D. Hunter, special agent of the Division of Entomology, Department of Agriculture, has, says Sczence, returned to Washington, after having studied the Turtle Moun- tain region in North Dakota and Manitoba, supposed to be a permanent breeding-ground of the Rocky Mountain locust. This, it is reported, he found not to be the case, and he thinks that the probable breeding-ground is the Assiniboine River, north and east of Regina, a region that will be investigated next season, ACCORDING to Mature Notes, a circular has just been issued to all Catholic missionaries by the Sacred Congregation of the NO. 1563, VOL. 60] NATURE 575 Propagation of the Faith, urging them to use such opportunities as the locality of their mission work affords for the collection of natural history specimens, to be given to scientific societies and institutions. The intention, it is asserted, is not only to interest and encourage such missionaries as are keen naturalists, but also to remove the reproach so commonly held that the Church does not look with favour upon science, and especially biological science, THERE being much difference of opinion as to the kind of ration best adapted for soldiers and sailors in tropical climates, a prize of 100 dollars, or a medal of that value, as the successful competitor may select, has, says the New York cor- respondent of the Zavce/, been offered by Dr. Louis L. Seaman for the best thesis on the subject, viz. ‘‘ The Ideal Ration for an Army in the Tropics.” The competition is open to all com- missioned medical officers of the U.S. army and navy, regular and volunteer. The prize is offered through the ‘* Military Service Institution of the United States.” The executive council of that body has decided that all papers should be sub- mitted by March 1, 1900. THE joint committee of the Glamorgan County Council and Cardiff Corporation invite applications for the post of bacterio- logist and lecturer, to work under the direction of the medical officers of health of the borough and county. Full particulars as to the duties and emoluments of the office will be found in our advertisement columns. Tue American Mathematical Society, which was established on its present basis so recently as 1894, appears to be in a flourishing condition. Its membership is now over three hundred, and at its recent summer meeting, held at Columbus, Ohio, simultaneously with that of the American Association, no fewer than twenty-four papers were read. In the address delivered at the opening of the winter session of the Jenner Institute of Preventive Medicine, on Monday last, Dr. Macfadyen gave an account of the institute and its work. In the course of his remarks he said the Anti-toxin Department was engaged in preparing various therapeutic serums, notably the anti-diphtheritic serum, as well as in research in sthis im- portant field of work. The primary object of the institute was research, but facilities were afforded for post-graduate instruc- tion in preventive medicine and bacteriology. The students had come from all parts of the world, and a considerable amount of original work had been done by those trained in the laboratories. Investigations were at present being made at the institute with reference to the possible cure or prevention of typhoid fever, tuberculosis and other diseases. The diagnosis of infectious diseases was constantly being carried out for the main parishes of London, as well as the investigation of ques- tions affecting the public health on behalf of sanitary authorities. The chemical and State medicine laboratories would find much to do in connection with water, sewage, food, poisons, &c. A notable addition had been made to the resources of the institute in the Hansen Laboratory for the study of the practical applica- tion of bacteriology to industrial and technical processes, and the most important results might be anticipated in the future from this branch of investigation. Tue New York Zéectrical Review gives particulars of a recently invented electrical and chemical fire-alarm apparatus, which gives its indications when the atmosphere becomes so vitiated with smoke that it will not support the combustion of a gas flame. In the interior of the apparatus a small gas flame constantly warms a thermostatic bar, the electric circuit through the apparatus being normally open as long as the flame holds out to burn. If the air in the apartment in which the apparatus is installed becomes vitiated with smoke, the little 576 NATURE [OcroBER 12, 1899 gas flame goes out, and the thermostatic bar, cooling off, closes the circuit and gives the alarm. At the International Fishery Congress held at Bergen in 1898, and at that held at Dieppe, an effort was made to start the publication of an ‘‘ International Review of Fisheries and Fish Culture,” which should serve to maintain constant relations between specialists of this branch of science working in different countries. Such efforts were, however, unsuccessful so far as a favourable decision of the Congresses being arrived at was concerned, This being so, and the want of such an organ being considered a very real one, the Russian Imperial Society of Fish Culture and Fisheries has undertaken the publication of such a periodical as has been mentioned, to con- tain articles in German, French and English. The first number, dated August, has just reached us and contains many interesting contributions, among which may be mentioned ‘‘ A Short Com- parison between the Caspian and the Baltic Seas,” ‘‘ Short Notices of the Fisheries of Sweden,” ‘‘ Fish Culture in the United States,” ‘Contributions to the Study of Fishing Apparatus.” The following programme will give an idea as to the scope of the new journal, which has made a very creditable beginning :—Ne w facts pertaining to fish- and oyster-culture (statistics, new methods used in fish-culture, inventions, &c.). New facts and data pertaining to fisheries (statistics, fishing news, inventions, new laws, &c.). Professional education of fishermen and of workmen engaged in the manufacture of preserved fish. Novelties in the manufacture of fish pro- ducts (new patents, new canneries, &c.). Improvements in the fish-trade and in the methods of carrying fish (fish-markets, cold-storage houses, refrigerator-cars ; new duties on imported fish). The work of fishery-societies. Review of scientific investigations connected with fisheries. New books on fish- culture and fishing. Personal notes. IN a recent number of the Paris Comptes rendus (vol. cxxix. p- 417), M. L. Teisserenc de Bort contributes some interesting particulars relating to the temperature of the free air and its variations from observations obtained from ninety unmanned balloons, sent up from his observatory at Trappes since April 1898. The observations have been spread over every month; seven of the ascents exceeded 14,000 metres, twenty-four 13,000 metres, and fifty-three attained a height of 9000 metres. The discussion of the observations exhibits the following general results : (1) The temperature at various heights presents during the course of the year important and greater variations than have been admitted from older series of observations made in manned balloons. The temperature of o° C. is found at very different altitudes, varying from the level of the ground in winter to above 4000 metres in summer. The isotherm of —25°C. is met with about 3000 metres in winter and above 7000 m, in summer; in September it was observed even above 8000 m. The isotherm of — 40° C. was several times found as lowas 6000 m., and is generally met with about 9000 m. and even higher towards the end of summer. The temperature of — 50°C. has never been recorded below 8000 m. ; its greatest altitude was at 12,000 m. (2) There appears to be a marked tendency to an annual variation of temperature even up to 10,000 m., the maxi- mum being about the end of the summer, and the minimum near the end of the winter. The observations given in a table ap- pended to the paper do not show such a rapid variability with height as has been generally supposed ; it appears, further, to vary with the type of weather. In the A¢tz det Lincez viii. (2) 4, Dr. D. Lo. Monaco and L. Panichi give a second note on the action of quinine on the parasite of malaria. The most remarkable result is the effect of solutions of strengths lying between certain limits in provoking the exit of the parasites from the red corpuscles, when the NO. 1563, VOL. 60] parasites are in the second or adult stage. The authors now find that the action of quinine on the endoglobular parasites of spring fever may be thus summed up: (1) in very dilute solutions it excites them ; (2) in less dilute solutions the excite- ment, which reaches its maximum phase in the exit of the parasite from the red corpuscle, is preceded by a brief con- traction ; (3) in strong or concentrated solutions it paralyses them. There is still some doubt as to the dose of quinine which should be administered in order to effect a cure, and this probably varies in different patients ; but it appears that the doses commonly adopted must be regarded as excessive, and that the rational dose suited for curing an attack of spring fever is comprised between half a gramme and a gramme of bisul- phate of quinine. : THE Silzungsherichte der physikalisch medicinischen’ Societét (Erlangen) contains abstracts of several experiments on kathodic rays. The first of these, by Prof. E. Wiedemann and A. Wehnelt, isa simple proof that while kathodic rays are deflected by a magnet, the Goldstein rays are not directly influenced by mag- netic force. In the second note the same authors deal with the question of the repulsion of converging kathodic rays, and de- scribe experiments showing that the rays emanating from a hollow kathode cut one another, and that this result is not inconsistent with Weber’s experiments. The third note deals with the variations in the potential of discharge in the kathodic dark space, and their independence of ultra-violet or Rontgen rays. Prof. E, Wiedemann contributes a further note on the “‘simple” kathodic rays of Deslandres. M. Arnold discusses the influence of the luminosity of the anti-kathode on the emis- sion of Réntgen rays; and A. Moffatt gives an interesting note showing that the power of Rontgen rays (ze. their energy divided by the time) is greater than is commonly supposed, and may be about 1 to 10 calories per second. THE Calabro-Messinese earthquake of November 16, 1894, occupies a prominent place among recent Italian shocks. A Government commission was immediately appointed to study it, but, for various reasons, the complete report has not yet been published. Prof. Ricco, however, has contributed a summary of the seismological section to the Royal Accademia dei Lincei (Rendiconti, vol. viii. pp. 3-12, 35-45), and has illustrated it by a map showing the isoseismal lines of the principal shocks of 1894 and 1783. The meizoseismal area of the earthquake of 1894 is situated about twenty miles north-east of Reggio, and the isoseismal lines (which depend, however, on observations from only 170 places) are roughly concentric with this area, but they expand towards the north-west, and are rather crowded together towards the south-east. Asa general rule, they follow the boundaries of the great crystalline masses. The total disturbed area (included within the isoseismal 2) is about 44,000 square miles. Nearly a thousand houses were com- pletely destroyed, and more than 44,000 were damaged ; about a hundred persons were killed, and a thousand wounded. The earthquake was registered by seismographs at seven Italian observatories, and by the horizontal pendulum at Nicolaiew. A puteometer at Catania indicated a sudden rise of 17 mm. in the well-water, followed by a fall of 14 mm., after which the surface returned nearly to its original position. The mean surface- velocity of the larger vibrations in Italy was almost exactly 2 km. per second ; but it varied with the distance, for the hodograph (see NATURE, vol. lii. p. 632) is at first convex to the axis of the distance and afterwards concave. Prof. Riccd remarks that the earthquake of 1894 may be regarded as an alter-shock of the great earthquake of 1783, its epicentre being displaced slightly to the south-west; but its intensity was much less, for the meizoseismal area (that bounded: by the isoseismal 10) is only one-sixth of that of the earthquake of 1783. OcrTosER 12, 1899] THE department of vertebrate paleeontology of the American Museum of Natural History reports that in 1898 the second expedition for Dinosaurs was sent out to Wyoming in charge of Dr. J. L. Wortman, with a party of four. Deposits of Dinosaur bones very favourably situated were found. In all some 60,000 pounds of fossils were secured. This splendid collection reached the museum entirely uninjured, and one- third of it has already been worked out. The fore and hind limbs of these monster reptiles will furnish subjects of great interest for the public. The exhibition hall has been enriched by the skeletons of two great Dinosaurs. A second party, under the direction of Dr. W. D. Matthew, was at work in 1898 in the fossil beds of north-western Kansas and south- western Nebraska. The Bad Lands of north-eastern Colorado were also found to be a rich collecting-ground. Skulls and parts of skeletons were secured, filling many important gaps in the Museum collection. Portions of skeletons and skulls of fossil camels were found, among which is included a gigantic one of the size and proportions of the giraffe. The party also acquired a large amount of other material. It is a little sur- prising to notice that, though the museum is doing so much to promote educational and scientific advancement in New York, the income in 1898 was insufficient to meet current expenses. THE monograph, ‘‘The Later Extinct Floras of the United States,” left unfinished by the death of Prof. Newberry, is to be completed by Dr. Arthur Hollick. THE Essex Technical Instruction Committee have issued, through the County Technical Laboratories, Chelmsford, a report, compiled by Mr. T. S. Dymond, of a visit paid to Holland by Essex agriculturists in May and June of the present year. The report is interesting reading, and gives a brief out- line of the more prominent features of Dutch farming. A perusal of the pamphlet will supply English agriculturists with a few hints which in some cases might with advantage be acted upon in this country. THE report of the Connecticut Agricultural Experiment Station for 1898 has just been published, and is full of valuable matter. Several of the reports contained in the volume should be of interest and service, not only to inhabitants of the State of Connecticut, but to many others. A SERIES of illustrated articles on ‘‘ Radiography,” by Mr. James Quick, is begun in the October number of Sczence Gossip. The same issue also contains the continuation of articles on ‘* British Freshwater Mites” and ‘‘ Butterflies of the Palearctic Region,” and numerous other contributions of popular science. THE Royal Technical Institute, Salford, has issued its calendar for the session 1899-1900. The list of classes is a large one, and, judging from the illustrations of laboratories, workshops, &c., given, the institute is equipped in a very efficient manner. THE additions to the Zoological Society’s Gardens during the past week include a Smooth-headed Capuchin (Cedus monachus) from South-east Brazil, presented by Mr. M. P. Peeker ; a Chopi Starling (4Aphobus chop) from Brazil, pre- sented by Mr. W. R. Routledge ; two Orange-flanked Parra- keets (Brotogerys pyrrhopterus) from Western Ecuador, pre- sented by Mr. W. H. St. Quintin; three Palm Squirrels (Scéurus palmarum) from India, presented by Mrs. M. E. Tracy; a Brown Capuchin (Cedus fatuellus) from Guiana, a Guinea Baboon (Cynocephalus sphinx) from Africa, a Striped Snake (77opidonotus ordinatus strtalis) from North America, three Common Snakes (7Zy%ofzdonotus natrix), a Four-lined Snake (Coluber guatuorlineatus), a Tessellated Snake ( 7yofid- onotus tessellatus), a Smooth Snake (Coronella austriaca), a NO. 1563, VOL. 60| NATURE om Glass Snake (Ophzosaurus apus), an Eyed Lizard (Lacerta ocel- fata), six Slowworms (Angus fragilis), European, deposited ; two Baillon’s Aracaris (Andigena ballon?) from Brazil, a White- browed Amazon (Chrysotés albifrons) from Honduras, twelve Dwarf Chameleons (Chamaeleon pumilus) from South Africa, purchased ; a Wapiti Deer (Cervus canadensis), an Axis Deer (Cervus axts), born in the Gardens. OUR ASTRONOMICAL COLUMN. CoMET GIACOBINI (1899 E).—We have received the follow- ing elements and ephemeris (calculated by Herr J. Moller) from the Centralstelle at Kiel. Elements, T = 1899 Aug. 26'707._ Berlin Mean Time. o= 358 46°1) Q = 273 26'9 ;1899'0 F log 7 = 0'23796 Ephemeris for 12h. Berlin Mean Time. 1899. R.A. Decl. Br. h. m. s , Oct. 5 16 3659 —3 187 . 0193 7 39 50 2 414 9 42 42 2ySer . 0°86 II 45 34 1 29°5 13 48 27 0 54°6 ... o'81 15 51 20 -0O 20°3 17 54 14 +0 133 . 0°76 19 16 57 8 +0 464 Hotmgs’ Comer (1899 @).—M. H. J. Zwiers gives in As? Nach. (Bd. 150, No. 3595) an extended ephemeris of this comet, in the hope that it may still be observed by any one having the necessary optical power, and thus permit of a more exact determination of this orbit. Br. 1899. R.A. Decl oo, _™m Ss O 7 u (AF (ra)? Oct. Wey 25590145 a75: +48 10 16°1 13 58 53°29 16 57°5 14 57 58°94 23 18°9 15 iy, ele 29 19°7 0°1647 0°05900 16 56 4°85 34 598 17 55 5°26 4o 18°7 18 54 4°07 45 16°1 19 253 1°35 +48 49 51°7 THE ROTATION OF THE SUN.—In a publication issued from the Lund Observatory, Herr C. A. Schultz Steinheil gives the results of his complete discussion of Dunér’s spectroscopic determinations of the sun’s rotation, extending over the period June 3, 1887—May 18, 1889. Taking Dunér’s spectroscopic values for different positions round the limb and the centre, these are reduced to heliographic coordinates by a table of declination corrections supplied to the author by M. Dunér, and so furnish over 600 equations of con- dition, which when grouped according to latitude are brought down to 22, Solving these by the method of least squares, the final result appears as x = 2°054 + 00042 2 = + 18°12 + 0°25 2 = + 28°00 + 0°50 This means that the result of the new discussion of Dunér’s spectroscopic observations is that the sun rotates so that a point on its equator moves with a uniform velocity of 2°054 kilo- metres per second round an axis the inclination of which to- wards the axis of the ecliptic is 18°'12, the longitude of the intersection of the sun’s equator with the ecliptic being + 28°:00. The value of the velocity x=2'054 is not the true velocity, but the synodic; we get the true value by adding 2d sin a, where @ is the velocity of the earth in its orbit in kilometres per second, and w the semi-diameter of the sun, expressed in angular measures as seen from the earth. THE PoLtaris MULTIPLE STAR.—Prof. W. W. Campbell is reported to have stated in the Mew York Times :— ““The recent observations of Polaris at the Lick Observatory 578 show that its velocity is variable. It is approaching the solar system now (September 12) with a velocity of 8 kilometres per second. This will increase in two days to 14 kilometres, and in the next two days will decrease to its former value of 8 kilo- metres. This cycle of changes is repeated every four days. .. . The orbit is nearly circular, and is comparable in size with the moon’s orbit round the earth. “« This centre of gravity, and therefore the binary system, is ap- proaching the solar system at present with a velocity of 11°5 kilo- metres per second. A few measures of the velocity of Polaris made here (Lick) in 1896 gave its velocity of approach at the rate of 20 kilometres per second. Part of this change since 1896 could be due toa change in position of the orbit of the binary system, but most of it must have been produced by the attraction of a ¢hzrd body on the two bodies comprising the ‘ four-day’ system.” A CORRESPONDENT to the Sczentific American (September 16) says that Mr. J. A. Brashear has just completed one of the pair of large astronomical camera doublets for the Observatory of the University of Heidelberg. They are next to the largest so far made, being 16 inches clear aperture and 80 inches focal length. Two of these doublets, each consisting of four lenses, are to be made, and are to be used almost exclu- sively for the photographic discovery of new asteroids. The reason for using two cameras is to provide a check on the possible inaccuracies inseparable from the use of photographic plates, such as false images, &c. The track of an asteroid with a lens of this focus on an § x Io plate is only about one-twentieth of an inch long for an exposure of three hours. As the curves of the lenses have necessarily to be very deep, the casting of the great discs was found to be very troublesome. The fund for the equipment has been provided by Miss Catherine Bruce, of New York City, who was also the donor of the largest photographic doublet (24-inch aperture), to the Harvard College Observatory at Arequipa. WE learn from the Zventng Standard that the expedition sent by the Vienna Academy of Science to India to observe the shower of meteoric Leonids during the night of November 14-15, or the following night, has started from Trieste. The leader of the ex- pedition is Herr Director Weiss, of the Vienna Observatory, who is accompanied by Prof. von Hepperger, of the Gratz University, the astronomers, Dr. Hillebrand, Dr. Prey, Herr Rheder, and Dr. Mache. The Indian Government has promised to give the expedition, which will make its observations near Delhi, every possible assistance. THE FREEDOM OF THE CITY OF MANCHESTER. ON Friday, October 6, the City of Manchester conferred her freedom on Enrigueta Augustina Rylands, Robert Dukin- field Darbishire, and Richard Copley Christie. Mrs. RYLANDs. Mrs. Rylands presented to the city the library, magnificent in its contents and beautiful in its fabric, which she built in memory of her husband, John Rylands, whose name it bears— John Rylands, who as ‘* a Manchester merchant built up from the lowliest beginnings a business of unparalleled magnitude, and left behind him a name for industry that never hasted nor rested, and a probity that knew no shame.” Principal Fairbairn, in his inaugural address, drew a remark- able parallel between Alexandria, whose library was the richest in the world, and Manchester, ‘‘ cities, whose princes were mer- chants and whose merchants princes,” and, he added, ‘‘ every- thing that raises a great provincial and industrial city to metro- politan rank makes for higher order, sweeter life and purer manners.” The opening of this great library calls for national jubilation. The noble fabric, designed by Mr. Basil Champneys, is in the fourteenth century Gothic style, and is possibly the finest building erected in England in this generation. The building is built entirely of Penrith limestone, the exterior being the dark red Barbary stone, and the interior delicately shaded Shawk stone. The staircase which leads to the main library is surmounted with a beautiful octagonal lantern surrounded by a carved stone gallery. The library proper is set back ten feet from the line of the building in order to secure a sufficient supply of light, and is NO. 1563, VOL. 60] NATURE [OcToBER 12, 1899 built on the collegiate plan ina long aisle ending in an apse, the total length being 148 feet. ri The building is vaulted.and groined throughout in stone, it is divided into eight bays occupied by bookcases, and contains a gallery in which this arrangement is repeated ; two large rooms opening from the apse contain the collection of Bibles, and the maps. The whole building is elaborately finished with statues and carving, and the fittings are all in harmony with the general scheme of decoration. Two beautiful traceried windows, by Mr. Charles Kempe, form a notable addition to the beauties of the building. The library contains the famous Althorp collection, and Mrs. Rylands’ private collection, which contains Wycliffe MSS. and Wynkyn de Wordes ; the library has been endowed, and will be kept up to date. Mr. R. D. DARBISHIRE AND Mr. R. C. CHRISTIE. When Sir Joseph Whitworth lay on his deathbed he at- tempted to complete a scheme for the utilisation of his property. But he could not explain so vast an idea, and, throwing out his hands, exclaimed ‘‘ I cannot do it now ; I must leave it to you, who know what it means !”’ And it was to Lady Whitworth, to Mr. Christie and to Mr. Darbishire that he left his great wealth. Lady Whitworth has followed her husband ; Manchester has created the two remaining co-legatees her honorary citizens in recognition of the admirable way they have carried out their trust. In connection with this trust, the legatees presented the site of the Manchester Technical School, and contributed largely to the School of Art ; made many valuable gifts of money to the Owens College for the engineering laboratory, the museum, the college hospital property, and for general purposes; and presented ten acres of valuable land as an athletic ground for the College ; finally presented the Whitworth Hall, now in course of erection at a cost of 50,000/. Presented and partially endowed the Whitworth Park and Art Gallery ; erected a public library and hall at Openshaw (where Sir J. Whitworth and Co.’s works are situated). In addition to the great personal labours in the wise and generous application of the Whitworth estate, Mr. Christie rendered invaluable service to the College in the times of storm and stress. Mr. Christie occupied in 1854-5 the united Chairs of History, Political Economy, Law and Jurisprudence. He is president of many learned societies, and chairman of numerous public bodies, charities and trusts ; he is president of the Cancer Home and Pavilion, an admirable institution which originated in his generosity. His chief literary production is the masterly biography of Etienne Dolet, the second edition of which has just been published. The magnificent new library at the Owens College which bears his name was his personal gift, and was erected at a cost of 21,000/. The total sum which passed through the hands of the Whit- worth Trustees was 1,250,000/. ; of that sum, 250,000/. was spent in redeeming promises and obligations, and the legatees themselves are responsible tor the distribution of 960,000/. W. T. L. VISIT OF THE INSTITUTION OF ELEC. TRICAL ENGINEERS TO SWITZERLAND, AUGUST 31 TO SEPTEMBER 8. ONSERVATIVE principles are no doubt of considerable service to England, but perhaps least so when applied to the problems of industry. It is a curious and_ possibly significant fact that as an electrical power England occupies a very insignificant position, and this in spite of the circumstance that the foundations of the industry were to a great extent laid by English engineers. Some years ago a very authoritative statement was made that in so far as ships of war are concerned our best policy is to watch the experiments of foreign nations and to profit by them, rather than make experiments for our- selves ; and it is not uncommon to hear similar remarks with regard to the industrial use of electrical appliances. Unhappily we seem to have forgotten the immense advantages which have accrued to us from our pioneering of the railway industry. No doubt in the early days many mistakes were made and much OcrToBER 12, 1899] NATURE 579 money was spent in railway experimenting, which foreign countries were afterwards saved ; but meanwhile the railway industry had become established in England, and other countries were for many years practically compelled to purchase their railway equipments in England. It seems to the writer of this article that the position formerly occupied by England in railway matters has been taken by America in respect of electric traction, and by Switzerland in regard to the industry of the distribution of electric power. We now certainly profit by American pioneering in electric lighting and tramway work— but we do not get their experience for nothing, for meanwhile their manufacturing industries have become established, and America takes tithe of us when we become her customers. In Switzerland the absence of coal and the presence of an industrious and highly educated population has no doubt co-operated to bring about the;wonderful progress which has been made in developing water powers electrically, and in establishing the corresponding industry of the manufacture of electrical appliances. It was on all accounts a happy inspiration for the Institution of Electrical Engineers to visit Switzerland, and for its members to become personally acquainted with the great electrical works of that country ; it is only to be regretted that the remainder of the British public did not accompany the members. Of course we had long understood that the Swiss had done great things electrically, but a visit was necessary to enable us to form an adequate idea of the industrial revolution which has been effected, and whose importance it is impossible to over- estimate. It is also impossible to overestimate the kindly hospitality which was extended to the Institution by the great Swiss manufacturing firms, and indeed by the whole electrical fraternity of Switzerland. We were received everywhere with open arms, works were not only thrown open to our inspection, but every effort was made to explain everything that required explanation, and we were made to feel that not only were we guests, but welcome guests. The following brief account is not intended to be a technical description of our visit, for which the electrical journals may be consulted (an excellent account has already appeared in Engineering), but is rather in the nature of a record of the writer’s general impressions. September 1.—About half the party arrived at Bale in the morning and spent the afternoon in a visit to the Alioth works at Miinchenstein. There is a great similarity between these works and those of Brown, Boveri and Co. at Baden ; both are new, both are clean, both are worked for the most part by polyphase motors, both of them make excellently designed machinery, mostly of the alternate current three-phase type, and both of them seemed to have as much work on hand as they could carry out. Though a minor matter, the design of the brush holders for continuous current dynamos at Miinchenstein met with some attention; they were very neatly made of aluminium on correct dynamical principles. September 2.—The rest of the party having arrived we went to see the great Power Station at Rheinfelden on the right hand bank of the Rhine. This station has a capacity of twenty turbines of 840 horse power each, the power being supplied by the water of the Rhine with a fall of from three to five metres. To meet variations in the level of the river, the turbines are con- structed in a rather peculiar manner, and in fact consist of two turbines on one shaft. The turbine shafts are supported on an oil film, pumped in below a flange ; the same high pressure oil being also employed to work the differential governing gear, which it appeared to do very well indeed. However, the load on the dynamos at Rheinfelden is pretty steady, but we found at some other stations that regulation was performed by hand, especially when the power was used for railway or tramway pur- poses. Some of the power is used for lighting and motors in the villages round about Rheinfelden, and up to a considerable distance away, the three-phase system being employed at a line pressure of 6800 volts. The bulk of the power, however, is used for chemical works on the spot, viz., aluminium, soda and bleach, and carbide, but we were not allowed to see any of these works. The power is a good deal cheaper than at Niagara, and the whole installation gave one the idea that it had “‘come to stay,” the hydraulic works being very solid and the power house roomy and convenient and well kept, though no doubt it had suffered an extra clean up. The party was entertained at lunch by the directors of the Rheinfelden works ; and Herr Rathenau came from Berlin to welcome us, and give us an invitation to visit Berlin next year, NO. 1563, VOL. 60] an invitation which it is to be hoped the Institution will accept ; in any case, Herr Rathenau deserves our best thanks. In the afternoon we went on by train to the works of Brown, Boveri and Co. at Baden (Switzerland). The works are fairly large, 1300 men and a staff of 170 being employed, and are as much as possible under one roof. Here we saw much the same kind of work that we had seen at the Alioth works, but on a much larger scale. The most interesting exhibit was un- doubtedly Mr. C. E. L. Brown himself, who took great pains to ensure our seeing as much as possible in the time at our disposal. The bulk of the work appears to be the construction of three-phase generators and motors of the ordinary type. The large generators were mounted very conveniently with the fixed portion (armature) on trunnions so that it could be turned round for the convenient execution of repairs. The tools were very modern, but there was not nearly so much repeat work being done as the writer at least had expected: nor was there any show of automatic machines. In fact the works were more like an English than an American works, though on a larger scale and newer than any similar works in England. September 4.—The party being now at Ziirich, expeditions were made to the Ziirich central station, the works of the Oerlikon Company, the gas engine power house of the Ziirich- Oerlikon-Seebach tramway, and the works of Messrs. Escher, Wyss and Co. The Central Power Station.—The whole of the water of the river Limmat, which drains the Lake of Ziirich, is, or can be, turned through the turbines of the power station, the general construction being very similar to that at Rheinfelden. A good deal of the power is used for pumping water, the excess water being used in high pressure turbines for electric generation. The Oerlikon works are very like the works at Baden, but are much older, and the generators on the three-phase principle appeared to be chiefly of the inductor type. The design of the three-phase motors appears to depend very much on the size, the small ones having simple short circuited squirrel-cage rotors, while the larger ones have a regular winding, coupled up star fashion, and arranged for the introduction or removal of resistance by pulling or pressing a rod passing up the rotor shaft. We saw a nearly-finished locomotive for the Jungfrau railway, the motors being three-phase and provided with enormous rheostats for varying the speed and absorbing power when the cars run down hill. Who would have thought twenty years ago that the Arago disc contained such potentialities ? The steel castings in this works were good throughout. The works of Escher, Wyss and Co. do not demand any special note in so far as arrangement, &c., is concerned ; but the firm seems thoroughly to understand the art of turbine making, as it should do, seeing that most of the turbines in the country appear to have been made at their works. Special pains were taken here to show us everything that was to be seen, and we had an unrivalled opportunity of inspecting the details of turbine construction. Dowson Gas Central Station of the Ziirich Oerlikon Street Railway at Oerlikon.—It was rather a surprise to us to find the street railway driven by Dowson Gas in a land reputed to be covered with water powers. The writer must admit to feeling a certain amount of satisfaction at the idea that the water powers were getting exhausted in the neighbourhood of Ziirich before British Industry had become a thing of the past. The truth is that there will be no more cheap power for Ziirich until some one or other of the numerous schemes for converting valleys into lakes is actually accomplished and very likely not even then. With regard to the Dowson plant itself, there was nothing very striking about it. The engines were not particularly large, but they appeared well made and particularly well water-jacketed. Little or no information could be obtained of interest to Gas Engine people ; but economy of coal must be a great consider- ation when it costs 32 francs per 1000 kilos. At the Selnau Transformer Station we had an opportunity of seeing how high-tension three-phase currents are used for trans- mitting power to a sub-station at which continuous current at 500 volts is generated for driving tramway motors. One of the most interesting things about this sub-station was the switches used for turning on the three-phase current, and so starting the continuous current generators to which the three-phase motors are directly coupled. As is, of course, well known, it is in general necessary that resistance should be inserted in the rotor circuit of a three-phase motor in order to enable it to start under any sort of a load. At the Selnau sub-station the switch 580 board was placed above a kind of stone cellar into which the high pressure leads were conducted, the pressure being 2000 volts. By moving the levers on the switch board the current could be switched on and resistance gradually removed from the star winding in the rotor circuits, so that by the time these had attained their proper speed, all the additional resistance had been cut out. We saw the operation of starting successfully performed. A number of diagrams had been prepared to illustrate to us the essential characteristics of the apparatus. One of these curves seemed to show that the efficiency of the three-phase motors remained within a very small percentage of the same value, the load increasing from 40 per cent. to its full value, a fact which seems to illustrate the great advantage which may be and is obtained by using these motors on variable loads. Viset to Schaffhausen and Neuhausen.—-One is, of course, always pleased to see Schaffhausen on its own account, but there did not seem any particular electrical reason for visiting it. There is the usual central station, power being taken from the Rhine with a fall of from 4 to 5 metres. A little higher up the river there is another similar but older station, the tail race of which is built under the head race of the lower station. One of the turbines was governed by a device which looked about as simple as. the machinery employed in cotton spinning, but it seemed to act all the same, though not better than the simpler devices employed by Escher, Wyss and Co. Some of the electric power is used for driving the machinery of a worsted spinning mill and twine works which were visited by several members of the party. Some of the water of the Rhine is deflected, one might almost say stolen, from above the falls at Neuhausen to work a plant most artistically situated just opposite the castle. There is no question but that the appearance of the falls has suffered by the water so deflected, and it is understood that local vested interest in the appearance of the falls is likely to prove too strong for those who desire to utilise their power. Part of the afternoon was spent in a visit to the works of Messrs. Sulzer Bros. at Winterthur, so well known to engineers as the birthplace of economical engines. We saw several of the engines whose economic performances have secured the admir- ation of the engineering world. They are of the compound, tandem type, with modified Corliss valve gear, both cylinders being steam jacketed, and heavily lagged with a non-conducting compound. Outside all is a coating of planished steel, which gives the engine a remarkably fine appearance. It appears that there is some evidence that these engines have on occasion developed one I.H.P. on as little as six kilos of steam. On Wednesday, September 6, a meeting of the Institution of Electrical Engineers was held in the great hall of the Poly- technikum, to hear a paper by Prof. Amsler on the water power at Schaffhausen. Dr. Amsler was not present himself, his paper being read by the secretary, and afterwards discussed indis- criminately by the English and Swiss engineers present. It is not to be inferred from this that they necessarily understood one another ; in fact, the writer was rather surprised to find that the linguistic powers of Swiss engineers do not appear to be appreciably greater than those of their English com/réres. It is usual to see the Polytechnikum of Ziirich held up for our admiration as representing all that is best in technical edu- cation. If magnificence of building, opulence in apparatus and luxury of appointment constitutes a successful Polytechnik, then there is no doubt that quite apart from its staff the Zurich insti- tution deserves the position which it apparently commands. The writer cannot help saying that he did not see a single piece of apparatus which he had not seen thousands of times before, that nearly all the apparatus in the Physical Laboratory appeared to him to be clumsy and old-fashioned in design, and that he saw no evidence of anything except an immense amount of what may perhaps be suitably described as second-class teaching of the ‘‘fife and drum” order. With regard to the Chemical Laboratory, the appliances were magnificent ; but there again, so far as the actual laboratories were concerned, there was not very much of interest, or if there was we did not see it. The basement of the chemical building was taken up by the most magnificent appliances for drawing in fresh air, either through a stream of water in summer time, or over a heated surface in winter, the whole of the air supply of the building being treated in this manner. So far as the writer could judge, the electro technic department appeared to be the most interesting part of the Polytechnikum, and there was no lack of machinery of all kinds of the latest type. It is understood that the Swiss elec- NO. 1563, VOL. 60] NATURE [OcToBER 12, 1899 trical manufactories make great use of the facilities for testing afforded by the electro technic department of the Poly- technikum. It is fair to add that we were rather hurried in our visit ; neither the writer nor any one else saw the whole of the departments ; and it was the middle of vacation time, when the busiest chemical laboratory looks like a desert. Thursday, September 7, was practically occupied by a cheap trip to Engelberg, except that it was not particularly cheap. The greater number of the members visited the Stansstad- Engelberg Railway, and for the first time the majority were able to see how a railway may be driven by means of three-phase motors. The starting and stopping of these machines apparently goes on in the smoothest way, and when the cars are running downhill the motors work as generators and pump power back to the generating station, where it is absorbed by resistances. A still better illustration of traction on the three-phase system was afforded by the visit on the last day of the meeting to the Kander power station, near Spiess, and then to the Burgdorf- Thun Railway. In fact, there was a tolerable consensus of opinion that this was the most important day of the tour. The Kander station is not large, but is equipped in the most modern manner by Brown, Bowri and Co. The water of the Kander at Spiezwyler, with an effective head of about 69 metres, is carried in an iron pipe down to the turbine house, where it operates turbines of about 900 horse-power working upon three- phase alternate current generators working at 4000 volts ‘* com- posed” pressure and 40 cycles per second. This current is partially used for distribution in the neighbourhood ; it is partly raised to 16,000 volts, and transmitted to Berne, Burgdorf and Munsingen, where it is re-transformed and used for general purposes. In addition to this, a large part of the power is transmitted at 16,000 volts, and distributed by means of trans- former stations along the course of the Burgdorf-Thun Railway at a pressure of 750 volts. Now an electric railway, as every- body knows, takes its power in a very irregular manner, so that the engineers of the Kander station have had to face the difti- culty of regulating a load part of which is practically constant and part of which is exceedingly variable. Some, if not all, of the generators are run in parallel, which means that all of them run strictly in synchronism ; consequently, if a load varies, the water-supply must be varied to each turbine at the same time and in the same manner. This was being accomplished by the apparently primitive device of having a man on the stop-valve of each turbine. The writer does not feel that he is entitled to pass an opinion on this practice ; but on men- tioning what he had seen to M. R. Thury, of Geneva, who has had immense experience of hydraulic electric stations, that engineer expressed himself as confident that it is quite possible to regulate even such a variable load as that of the Kander automatically. The writer was informed that there was an accident to the water pipes at the Kander station not very long ago which upset the regulating devices. The pressure at which “the current 1s generated was regulated by two men at the switch board, who constantly varied the exciting current of the exciters of the generators, which was itself furnished by an independent dynamo which was the subject of regulation. Ina station of this kind the difficulty of regulation is no doubt affected by the fact that any variation in the water supplied to the turbines necessarily alters the pressure under which the water is delivered. The switch board was a fine complicated affair on a base of white marble, and some of the fittings appeared to be from America. Burgdorf-Thun Ratlway.—This railway, 40 kilometres long, is not distinguished in any way from an ordinary railway except that it is being worked electrically by power transmitted from the Kander station. The rolling stock consists of ordinary carriages hauled by electric locomotives, each of which carries two asynchronous 300-horse power motors. The motors are connected with the axles through the intermediary of gearing which we were informed can be adjusted to run at either of two speeds, intermediate regulation being obtained by varying the existence of the rotor windings. Immense rheostats are required for motors of this kind, and are carried to a large extent on the top of the locomotive, so that it has a very strange appearance. Two trolley wires are used, the third one being of course the rails, and into this three-wire system current is fed at intervals by fourteen transformer stations. There is nothing of the tramway about this road. It forms part of the permanent railway system of Switzerland, and runs under much the same conditions as if the trains were hauled by steam locomotives. OcToBER 12, 1899] The average speed is about 18 kilometres per hour with a train of fifty-five tons. Besides the locomotives, automobile carriages equipped up to 240-horse power are provided for the greater part of the passenger traffic, and these trains run at 36 kilo- metres per hour. Nothing could have been smoother or more satisfactory than the way in which the train (hauled in this case by one locomotive) was stopped and started, and it got up its speed with satisfactory quickness. It may be safely predicted that though this is the first railway of the type (as distinguished from a tramway) it will not be the last, for the transmission of current at 16,000 volts does not demand wires of more than two millimetres diameter for the distances mentioned. No difficulty seems to be experienced in insulation. Ordinary insulators of the double petticoat type without oil are employed, and no special precautions are taken with regard to the posts on which these wires are supported except to inscribe upon them a genial warning as to the fate likely to befall anybody meddling with them. The railway up the Jungfrau is also a very interesting work, and an excellent day was spent in a visit to it. It goes up to the Rothstock a long way above the Wengern Alp, and there it ends at presentin a tunnel. It happened that while some of the party were standing close to the locomotive in the tunnel the line was struck by lightning, the fuses blown in the power station, and the automatic break on the locomotive instantly went into action, though the train was at rest. From the electrical point of view, there was not much to be seen on the Jungfrau Railway, but we had splendid weather, and regarded the trip as a day’s holiday. On the whole we may, perhaps, say that we saw more, but not better, electrical work than can be done in England. We saw that Swiss engineers have the courage of their convictions, and have done more in railway work than most of us had ever dreamed of ; and we saw that, as regards the carbide and similar industries, we cannot hope to compete in England till we can get at something cheaper than steam power. On the other hand, English industries in general cannot be regarded as threatened by Swiss enterprise ; and Switzerland itself, regarded as a manufacturing country, requires (as Mr. Raworth remarked) to be rolled and to have its lakes filled up. RICHARD THRELFALL, THE BRITISH ASSOCIATION. SECTION K. BOTANY. OPENING ADDRESS BY SiR GEORGE KING, K.C.LE., LL.D., F.R.S., PRESIDENT OF THE SECTION, A Shetch of the History of Indian Botany. THE earliest references in literature to Indian plants are, of course, those which occur in the Sanskrit classics. These are, however, for the most part vague and obscure. The interest which these references have, great as it may be, is not scientific, and they may therefore be omitted from consider- ation on the present occasion. The Portuguese, who were the first Europeans to appear in India as conquerors and settlers, did practically nothing in the way of describing the plants of their Eastern possessions. And the first contribution to the knowledge of the botany of what is now British India was made by the Dutch in the shape of the ‘‘ Hortus Malabaricus,” which was undertaken at the instance of Van Rheede, Governor of the territory of Malabar, which during the latter half of the seventeenth century had become a possession of Holland. This book, which is in twelve folio volumes and is illustrated by 794 plates, was published at Amsterdam between the years 1686 and 1703, under the editorship of the distinguished botanist Com- melyn. Van Rheede was himself only a botanical amateur, but he had a great love of plants and most enlightened ideas as to the value of a correct and scientific knowledge of them. The “ Hortus Malabaricus’’ was based on specimens collected by Brahmins, on drawings of many of the species made by Mathzeus, a Carmelite missionary at Cochin, and on descriptions originally drawn up in the vernacular language of Malabar, which were afterwards translated into Portuguese by Corneiro, a Portuguese official in Cochin, and from that language finally done into Latin by Van Douet. The whole of these operations were carried on under the general superintendence of Casearius, NO. 1563, VOL. 60] NATURE 581 a missionary at Cochin. Of this most interesting work the plates are the best part ; in fact, some of these are so good that there is no difficulty in identifying them with the species which they are intended to represent. The next important contribution to the botanical literature of Tropical Asia deals rather with the plants of Dutch than of British India. It was the work of George Everhard Rumph (a native of Hanover), a physician and merchant, who for some time was Dutch Consul at Amboina. The materials for this book were collected mainly by Rumphius himself, and the Latin descriptions and the drawings (of which there are over one thousand) were his own work. The book was printed in 1690, but it remained unpublished during the author’s lifetime. umph died at Amboina in 1706, and his manuscript, after lying for thirty years in the hands of the Dutch East India Company, was rescued from oblivion by Prof. John Burman, of Amsterdam (commonly known as the elder Burman), and was published under the title of ‘* Herbarium Amboinense,” in seven folio volumes, between the years 1741 and 1755. The illustrations of this work cover over a thousand species, but they are printed on 696 plates. These illustrations are as much inferior to those of Van Rheede’s book as the descriptions are superior to those of the latter The works of Plukenet, published in London between 1696 and 1705, in quarto, contain figures of a number of Indian plants which, although small in size, are generally good portraits, and therefore deserve mention in an enumeration of botanical books connected with British India. An account of the plants of Ceylon, under the name ‘‘ Thesaurus Zeylanicus,” was pub- lished in 1737 by John Burman (the elder Burman), and in this work many of the plants which are common to that island anil to Peninsular India are described. Burman’s book was founded on the collections of Paul Hermann, who spent seven years (from 1670 to 1677) exploring the flora of Ceylon at the expense of the Dutch East India Company. The nomenclature of the five books already mentioned is all uninominal. Hermann’s Cingalese collection fell, however, sixty years after the publication of Burman’s account of it, into the hands of Linnzeus, and that great systematist published in 1747 an account of such of the species as were adequately represented by specimens, under the title ‘‘ Flora Zeylanica.” This Her- mann herbarium, consisting of 600 species, may still be con- sulted at the British Museum, by the Trustees of which institu- tion it was acquired, along with many of the other treasures possessed by Sir Joseph Banks. Linnzeus’s ‘‘ Flora Zeylanica”’ was followed in 1768 by the ‘‘ Flora Indica” of Nicholas Bur- man (the younger Burman)—an inferior production, in which about 1500 species are described. The herbarium on which this “*Flora Indica” was founded now forms part of the great Herbarium Delessert at Geneva, The active study of botany on the binominal system of nomen- clature invented by Linnzeus was initiated in India itself by Koenig, a pupil of that great reformer and systematist. It will be convenient to divide the subsequent history of botanic science in India into two periods, the first extending from Koenig's arrival in India in 1768, to that of Sir Joseph Hooker's arrival in 1849; and the second from the latter date to the present day. The pioneer John Gerard Koenig was a native of the Baltic province of Courland. He was a correspondent of Linnzus, whose pupil he had formerly been. Koenig went out to the Danish settlement at Tranquebar (150 miles south of Madras) in 1768, and at once began the study of botany with all the fervour of an enthusiasm which he succeeded in imparting to various correspondents who were then settled near him in Southern India. These friends formed themselves into a society under the name of ‘‘ The United Brothers,” the chief object of their union being the promotion of botanical study. Three of these brothers, viz. Heyne, Klein and Rottler, were missionaries located near Tranquebar. Gradually the circle widened, and before the century closed the enthusiasm for botanic research had spread to the younger Presidency of Bengal, and the number of workers had increased to about twelve, among whom may be mentioned Fleming, Hunter, Anderson, Berry, John, Roxburgh, Buchanan (afterwards Buchanan-Hamilton), and Sir William Jones, so well known as an Oriental scholar. At first it was the custom of this brotherhood merely to exchange specimens, but gradually names began to be given, and specimens, both named and unnamed, began to be sent to botanists of established reput- ation in Europe. Many plants of Indian origin came thus to be described by Retz, Roth, Schrader, Willdenow, Vahl and 582 NATURE [OcToBER 12, 1899 Smith. Rottler was the only member of the band who him- self published in Europe descriptions of any of the new species of his own collecting, and these appeared in the ‘‘ Nova Acta Acad. Nat. Curiosorum” of Berlin. A little later Sonnerat and other botanists of the French settlement at Pondicherry sent large collections of plants to Paris, and these were fol- lowed ata considerably later date by the collections of Leschen- hault. These French collections were described chiefly by Lamarck and Poiret. Hitherto botanical work in India had been more or less desultory, and it was not until the establishment in 1787 of the Botanic Garden at Calcutta that a recognised centre of botanical activity was estab- lished in British India. Robert Kyd, the founder of that Garden, was more of a gardener than a botanist. He was, however, a man of much energy and shrewdness. The East India Company was still in 1787 a trading company, and a large part of their most profitable business was derived from the nutmegs and other spices exported from their settlements in Penang, Malacca, Amboina, Sumatra, and other islands of the Malayan Archipelago. The Company were also in those days the owners of a fine fleet of sailing vessels, and the teak of which these ships were built had to be obtained from sources outside the Company’s possessions. The proposal to found a botanic garden near Calcutta was thus recommended to the Governor of the Company’s settlements in Bengal on the ground that, by its means, the cultivation of teak and of the Malayan spices might be introduced into a province near one of the Company’s chief Indian centres. Kyd, as a Lieutenant-Colonel of the Com- pany’s engineers, and as secretary to the Military Board at Calcutta, occupied a position of considerable influence, and his suggestion evidently fell on no unwilling ears; for the Govern- ment of Bengal, with the promptitude to accept and to act on good advice in scientific and semi-scientific matters which has characterised them from the day of Kyd until now, lost no time in taking steps to find a site for the proposed garden. Colonel Kyd’s official proposal was dated June 1, 1786, and, in a despatch dated August 2, the Calcutta Government recom- mended Kyd’s proposal to the Court of Directors in London, Posts were slow and infrequent in those days, and the Calcutta Government were impatient. They did not wait for a reply from Leadenhall Street, but in the following July they boldly secured the site recommended by Colonel Kyd. This site covered an area of 300 acres, and the whole of it, with the exception of thirty acres which were subsequently given up to Bishop Middleton for an English college, still continues under cultivation as a botanic garden. Kyd died in 1793, and in the same year his place as superintendent of the garden was taken by Dr. William Roxburgh, a young botanical enthusiast, and one of Koenig’s ‘‘ United Brother- hood.” Roxburgh had studied botany in Edinburgh, where he was a favourite pupil of Dr. Hope. Desirous of seeing some- thing of foreign countries, he made several voyages to Madras in ships belonging to the Honourable East India Company. In 1776 he accepted an appointment in the Company’s medical establishment, and was posted to the town of Madras, where he very soon made the acquaintance of Koenig. Roxburgh was shortly after transferred to a remote district, a good deal to the north of Madras, then named the Northern Circars. The station of Samulcotta, which formed Roxburgh’s headquarters during his sojourn in the Circars, stands on the edge of a hilly region possessing a very interesting flora, and this flora he explored with the greatest ardour ; and, as part of the result of his labours, an account of some of the most interesting of its plants was published in London, at the East India Company’s expense, in three large folio volumes, under the title, ‘‘ The Plants of the Coast of Coromandel.” This was Roxburgh’s earliest publication on a large scale. The first part of this book appeared in 1795, and the last not until 1819, z.e. five years after the authors death. The increased facilities afforded to Roxburgh after his transfer to a comparatively well-equipped institution like that at Calcutta induced him at once to begin the preparation of descriptions of all the plants indigenous to British India of which he could procure specimens. And so diligently did he work that, when he was finally driven from India by ill-health in 1813, he left complete and ready for pub- lication the manuscripts of his ‘‘ Flora Indica” and of his “‘Hortus Bengalensis”’ (the latter being an enumeration of the plants in cultivation in the Calcutta garden). He also left admirable coloured drawings (mostly of natural size) of 2533 species of plants indigenous to India. Seldom have twenty | NO. 1563, VOL. 60] years yielded so rich a botanical harvest! Dr. Roxburgh was thus the first botanist who attempted to draw up a systematic account of the plants of India, and his book, which is on the Linnzean system, is the basis of all subsequent works on Indian botany; and until the publication of Sir Joseph Hooker’s monumental ‘‘ Flora of British India,” it remained the only single book through whicha knowledge of Indian plants could be acquired. Roxburgh was immediately succeeded in the Calcutta garden by Dr. Buchanan-Hamilton, a man of many accomplish- ments, who had travelled from Nepal in the North to Ava and Mysore in the South, accumulating materials for a gazetteer of the Honourable Company’s possessions. Dr. Buchanan was a zoologist as well as a botanist. He had published a valuable account of Mysore, Canara and Malabar, and had collected materials for a work ‘on the Fishes of India, besides having accumulated a large herbarium, part of which may now be con- sulted at the University of Edinburgh. Prior to his death Buchanan- Hamilton had begun to write a learned commentary on Van Rheede’s ‘* Hortus Malabaricus.” Many of his Nepalese collections were described in 1825 (a few years before his own death) by Don in his ‘* Prodromus Flore Nepalensis.”” Buchanan-Hamilton remained only one year at Calcutia, and in 1815 he was succeeded by Nathaniel Wallich, a native of Copenhagen, who, prior to his appointment to the Calcutta garden, had been attached to the Danish settlement at Seram- pore, twenty miles higher up the Hooghly. Wallich remained superintendent of the Calcutta garden for thirty years. In 1846 he went to England, and in 1854 he died. During his tenure of office in the Calcutta garden, Wallich organised col- lecting expeditions to the then little-known regions of Kamaon and Nepal (in the Himalaya), to Oudh, Rohilcund, Sylhet, Tenasserim, Penang, and Singapore. He undertook, in fact, a botanical survey of a large part of the Company’s possessions in India. The vast materials thus collected under his own imme- diate direction, and the various contributions made by others, were taken to London by him in 1828. With these were sub- sequently incorporated the collections of Russell, Klein, Heyne, Rottler, Buchanan-Hamilton, Roxburgh, and Wight. And by the help of a band of distinguished European botanists, among whom may be named De Candolle, Kunth, Lindley, Meissner, Nees von Esenbeck, Von Martius and Bentham (the latter in a very special manner), this vast mass of material was classified and named specifically. A catalogue of the collection was prepared by Wallich himself (largely aided by Ben- tham), and sets of the named specimens were dis- tributed to the leading botanical institutions in Europe, every example of each species bearing the same number. No description of the whole collection was ever attempted, but many of the plants belonging to it were subsequently described in various places and at various times. So extensive was the Wallichian distribution that, amongst the names and synonyms. of tropical Asiatic plants, no citation is more frequent in botanical books than that of the contraction ‘* Wall. Cat.” Besides the naming and distribution of this gigantic collection, Wallich prepared and published, at the expense of the same liberal and enlightened East India Company, his ‘‘ Plante Asiaticze Rariores,” in three folio volumes with 300 coloured plates. He also contributed to an edition of Roxburgh’s. “*Flora Indica,” which was begun by the celebrated Dr. Carey of Serampore, descriptions of many plants of his own collecting. But the task of publishing his discoveries in this way proved beyond his powers, as it would have proved beyond those of any one who had only 365 days to his year, and less than a hundred years as his term of life! Carey and Wallich’s edition of Roxburgh’s ‘‘ Flora Indica” was brought to an untimely conclusion at the end of the Pentandria Monogynia of Linneus. Wallich also began an illustrated account of the flora of Nepal under the title, ‘‘ Tentamen Flore Nepalensis.’’ But this also came to a premature end with the publication of its second part. During much of the time that Wallich was labouring in Northern India, Robert Wight, a botanist of remarkable sagacity and of boundless energy, was labouring in Southern India, chiefly in parts of the Peninsula different from those in which Koenig and his band had worked. Wight was never liberally supported by the Government of Madras, and it was mostly by his own efforts and from his own resources that his collections were made and that his botanical works were published. The chief of the latter is his ‘‘ Icones Plantarum.” This book con- sists of figures with descriptions of more than two thousand Indian species. A good many of the plates are indeed copies OcToBER 12, 1899 | NATURE 583 from the suite of drawings already referred to as having been made at Calcutta by Dr. Roxburgh. The rest are from drawings made, either by native artists under his personal supervision, or by his own kands. Ample evidence of the extraordinary energy of Dr. Wight is afforded by the facts that, although he had to teach the native artists whom he employed both to draw and to lithograph, the two thousand Zcones which he published and described were issued during the short period of thirteen years, and that during the whole of this time he performed his official duties as a medical officer. Besides this magnum opus, Wight published his Spicelegdane Nilghirense in two vols. quarto, with 200 coloured plates. And between 1840 and 1850 he issued in two vols. quarto, with 200 plates, another book named ‘‘ Illustrations of Indian Botany,” the object of which was to give figures and fuller descriptions of some of the chief species described in a systematic book of the highest botanical merit, which he prepared conjointly with Dr. J. Walker-Arnot, Professor of Botany in the University of Glasgow, and which was published under the title ‘* Prodromus Flore Peninsule Indice.” The ‘‘Prodromus” was the first attempt at a flora of any part of India in which the natural system of classification was followed. Owing chiefly to the death of Dr. Walker-Arnot, this work was never completed, and this splendid fragment of a flora of Peninsular India ends with the natural order Défsaceae. ; The next great Indian botanist whose labours demand our attention is William Griffith. Born in 1810, sixteen years after Wight, and twenty-four years later than Wallich, Griffith died before either. But the labours even of such devotees to science as were these two are quite eclipsed by those of this most remarkable man. Griffith’s botanical career in India was begun in Tenas- serim. From thence he made botanical expeditions to the Assam valley, exploring the Mishmi, Khasia and Naga ranges. From the latter he passed by a route never since traversed by a botanist, through the Hookung valley down the Irrawadi to Rangoon. Having been appointed, soon after his arrival in Rangoon, surgeon to the Embassy to Bhotan, he explored part of that country and also part of the neighbouring one of Sikkim. At the conclusion of this exploration he was transferred to the opposite extremity of the Northern frontier, and was posted to the Army of the Indus. After the subjugation of Cabul, he penetrated to Khorassan. Subsequently he visited the portion of the Himalaya of which Simla is now the best-known spot. He then made arun down the Nerbudda valley in Central India, and finally appearedin Malacca as Civil Surgeon of that Settle- ment. At the latter place he soon died of an abscess of the liver brought on by the hardships he had undergone on his various travels, which were made under conditions most inimical to health, in countries then absolutely unvisited by Europeans. No botanist ever made such extensive explorations, nor himself collected so many species (9000) as Griffith did during the brief thirteen years of his Indian career; none ever made so many field notes or wrote so many descriptions of plants from living specimens. His botanical predecessors and contemporaries were men of ability and devotion. Griffith was a man of genius. He did not confine himself to the study of flowering plants, nor to the study of them from the point of view of their place in any system of classification. He also studied their morphology. The difficult problems in the latter naturally had most attraction for him, and we find him publishing, in the Linnaean Transactions, the results of his researches on the ovule’ in Santalum, Loranthus, Viscum, and Cycas. Griffith was also a cryptogamist. He collected, studied, and wrote much on Mosses, Liverworts, JZarsz/zaceae, and Lycopods, and he made hundreds of drawings to illustrate his microscopic observations. Wherever he travelled he made sketches of the most striking features in the scenery. THis habit of making notes was inveterate ; and his itinerary diaries are full of in- formation, not only on the botany, but also on the zoology, physical geography, geology, meteorology, archeology |and agriculture of the countries through which he passed. His manuscripts and drawings, although left in rather a chaotic state, were published after his death under the editorship of Dr. McClelland, at the expense of the enlightened and ever- liberal East India Company. They occupy six volumes in octavo, four in quarto, and one (a “‘ Monograph of Palms”’) in folio. Another botanist of much fame, who died prematurely in 1822, after an Indian career of only nine years, was William Jack. In 1814-15, Jack accompanied Ochterlony’s army to the NO. 1563, VOL. 60] Nepal terai. He was transferred in 1818 to the Company’s settlement in Sumatra under Sir Stamford Raffles, and during the four years of his residence in Sumatra he contributed to botanical literature descriptions of many new genera and species which were published in his ‘‘ Malayan Miscellanies.” His collections, un- fortunately, were for the most part lost by an accident, but those which were saved are now in the Herbarium Delessert in Geneva. Somewhat similar to Griffith in temperament and versatility was the brilliant Victor Jacquemont, a French botanist who, at the instance of the Paris Natural History Museum, travelled in India for three years from 1829 to 1832. During this period Jacquemont collected largely in the Gangetic plain. He then entered the North-west Himalaya at Mussourie, explored Ghar- wal and Sirmur, ascended the Sutlej to Kanawer and Piti (at that time unexplored), visited Cashmir, and returning to the plains, crossed Northern Rajputana to Malwa and the Deccan. He finally reached Bombay with the intention of returning to France. But at Bombay he succumbed to disease of the liver, brought on by hard work and exposure. His remains, after having lain in the cemetery there for fifty years, were, with that tender regard for the personality of her famous sons which France has always shown, exhumed in 1881, and conveyed in a French frigate to finda permanent resting-place in the place of Jacquemont’s birth. Jacquemont’s collections were trans- mitted to Paris, and his plants were described by Cambessedes and Decaisne, while his non-botanical collections were elaborated by workers in the branches of science to which they respectively appertained, the whole being published in four volumes quarto, at the expense of the French Government. The roll of eminent botanists who worked in India during the first half of the century closes with the name of Thomas Thomson, who collected plants extensively between 1842 and 1847 in Rohilkund and the Punjab, and again still more ex- tensively during a Government mission to the North-west Himalaya and Tibet which was continued from 1847 to 1849. During this period Dr. Thomson explored Simla, Kanawar, Piti, Cashmir, Ladak, and part of the Karakoram. His col- lections, which were large and important, were transmitted to the Botanic Garden at Calcutta, and thence in part to Kew. They formed no insignificant part of the materials en which the “‘ Flora Indica” and ‘‘ Flora of British India” were founded. Dr. Thomson also published an account of his travels—an admirable book, though now jostled out of memory by the quantities of subsequently issued books of Himalayan travel and adventure. About the year 1820 a second centre of botanical enterprise was established at Seharunpore, in the North-west Provinces. A large old garden near that important town, which had been originally founded by some Mahommedan nobles of the Delhi Court, was taken over by the Honourable Company, and was gradually put upon a scientific basis by Dr. George Govan, who was appointed its first superintendent. Dr. Govan was in 1823 succeeded by Dr. J. Forbes Royle, and he in 1832 by Dr. Hugh Falconer. Dr. Royle made collections in the Jumno- Gangetic plain, in the Lower Gharwal Himalaya, and in Cashmir. He was distinguished in the field of economic rather than in that of systematic botany, his chief contribution to the latter having been a folio volume entitled ‘‘ Illustrations of the Botany of the Himalaya Mountains.” His valuable labours as an economic botanist will be noticed later on. Hugh Falconer Was an accomplished paleontologist who devoted but little of his splendid talents to botany. His great contribution to palzontology, the value of which it is almost impossible to over-estimate, consisted of his exploration and classification of the tertiary fossils of the Sewalik range. Falconer was trans- ferred to the Calcutta Garden in 1842. He was succeeded at Seharunpore by Dr. W. Jameson, who explored the botany of Gharwal, Kamaon and Cashmir, but who published nothing botanical, his chief energies having been devoted to the useful work of introducing the cultivation of the China tea plant into British India, and this he did (as will afterwards be mentioned) with triumphant success. During the first half of the century a considerable amount of excellent botanic work was done in Western India by Graham, Law, Nimmo, Gibson, Stocks and Dalzell, the results of whose labours culminated in the preparation by Graham of a list of the plants of Bombay, which was not, however, published until 1839 (after his death); in the publication by Stocks of various papers on the botany of Scinde; and in the publi- 584 NATORE ([OcToBER 12, 1899 cation by Dalzell in 1861 of his ‘* Flora of Bombay.” It is im- possible in a brief review like the present to mention the names of all the workers who, in various parts of the gradually ex- tending Indian Empire, added to our knowledge of its botanical wealth. It must suffice to mention the names of a few of the chief, such as Hardwicke, Madden, Munro, Edgeworth, Lance and Vicary, who collected and observed in Northern India, and who all, except the two last mentioned, also published botanical papers and pamphlets of more or less importance ; Jenkins, Masters, Mack, Simons and Oldham, who all collected ex- tensively in Assam; Hofmeister, who accompanied Prince Waldemar of Prussia, and whose collections form the basis of the fine work by Klotsch and Garcke (7ezs. Pr. Wald.) ; Norris, Prince, Lobb and Cuming, whose labours were in Penang and Malacca ; and last, but not least, Strachey and Winterbottom, whose large and valuable collections, amounting to about 2000 species, were made during 1848 to 1850 in the higher ranges of the Kamaon and Gharwal Himalaya, and in the adjacent parts of Tibet. In referring to the latter classic Herbarium, Sir Joseph Hooker remarks that it is ‘‘ the most valuable for its size that has ever been distributed from India.” General Strachey is the only one who survives of the splendid band of collectors whom I have mentioned. I cannot conclude this brief account of the botanical labours of our first period without mentioning one more book, and that is the ‘‘ Hortus Calcuttensis” of Voigt. Under the form of a list, this excellent work, published in 1845, contains a great deal of information about the plants growing near Calcutta, either wild or in fields and gardens. It is strong in vernacular names and vegetable economics. (Zo be continued. ) MATHEMATICS AT THE BRITISH ASSOCIATION. HE visit of the French Association to Dover necessitated some departures from the usual programme of the British Association week, and the mathematical meeting was held this year on Monday, September 18. Prof. Forsyth, of Cambridge, presided over a well-filled room, The session opened with the formal communication of two reports of committees: the first, drawn .up by Prof. Karl Pearson, and practically forming a continuation of a previous report, contains a set of tables of certain functions connected with the integral G(r, v)= | ” sin "e"*a0, 0 for integral values of 7 from 1 to 50, and for values of v at cer- tain intervals from o to 1. These functions are of importance in certain statistical problems. The second report consists substantially of the new ‘“ Canon Arithmeticus” which Lieut.-Colonel Cunningham has _pre- pared ; the Association has made a grant for publishing the tables as a separate volume (they cannot well be fitted into the comparatively small page of the B.A. Report), and it is to be hoped that before long they will become generally available for workers in the Theory of Numbers. The first of the papers was read by Dr. Francis Galton, on “The Median Estimate.” Dr. Galton proposes to substitute a scientific method for the very unsatisfactory ways in which the collective opinion of committees and assemblies of various kinds is ascertained, in respect to the most suitable amount of money to be granted for any particular purpose. How is that medium amount to be ascertained which is the fairest compromise between many different opinions? An average value—z.e. the arithmetic mean of the different estimates—may greatly mislead, because a single voter is able to produce an effect far beyond his due share by writing down an unreasonably large or unreason- ably small sum. Again, few persons know what they want with sufficient clearness to enable them to express it in numerical terms, from-which alone an average may be derived; much deeper thought-searching is needed to enable a man to make such a precise affirmation as that ‘‘in my opinion the bonus to be given should be 8o/.,” than to enable him to say ‘‘I do not think he deserves so much as 100/., certainly not more than 100/.”’ Dr. Galton’s plan for discovering the medium of the various sums desired by the several voters is to specify any two reason- able amounts A and B, and to find what percentage a of voters think that the sum ought to be less than A, and what per- centage 4 vote for less than B. It may now be assumed that NO. 1563, VOL. 60] the estimates will be distributed on either side of their (unknown) median m, with an (unknown) quartile g, in approximate accordance with the normal law of frequency of error ; and thus (using the table of centiles given in the author’s ‘‘ Natural Inheritance *’) the required median value can be found, This was followed by a paper ‘‘ On a system of invariants for parallel configurations in space,” by Prof. Forsyth. The process followed by the author is one in which English mathe- maticians have always excelled—namely, the deduction of difficult analytical results from simple geometrical considerations. Prof. Forsyth’s final formulz may be regarded as invariantive relations between certain definite integrals ; the way in which he finds them is as follows :— Consider any plane curve; if we suppose a circle of constant size to roll on the curve, its envelope will be another curve, which is said to be farall/el to the original one. If now L be the length and A the area of a curve, it is found that the quantity A — 1 L? has the same value for the parallel as for the 47 original curve ; in other words, I ae A= reo is zzvardantive for parallel curves. Similarly in space of three dimensions, the envelope of a sphere of fixed size which rolls on a given surface is another parad/e/ surface ; and if V be the volume contained by a surface, S its superficial area, and L twice the surface-aggregate of the mean of the curvatures at any point, then it is found that the quantities I Sey fe To2m/ Lyte _i Se ea and V g,LS+ are invariantive for all parallel surfaces. Similar results hold for space of 7 dimensions. At the end of the paper the expressions obtained are shown to be connected with the ordinary invariant-theory of binary forms. The next paper, read by Prof. Everett, was concerned with “The Notation of the Calculus of Differences.” In conjunction with the ordinary symbol A, defined by DBIn=In41—Ins Prof. Everett employs another symbol 6, defined by dyn =In-In-1> so that 8=A/, +4. The use of 5 simplifies some of the well-known formulz of the calculus of finite differences. Prof. A. C. Dixon, of Galway, followed, with a paper ‘‘On the Partial Differential Equation of the Second Order.” Let z be the dependent, and x and y the independent, variables ; and with the usual notation, let Oz Oz 02" 02" Oz" = = a = a — ax «oy aoe axdy, ay, and consider the differential equation T(x, Is 25 Pr Ws 7s Sy th=0, This may be supposed solved by using two more relations = 0h DSF among the quantities «, y, 2, 2, 7, 7 5, ¢, to give values of 7, s, 2, which, when substituted in dz=pax + qdy, adp=rdx+say, dg=six+tdy, render these three equations integrable. This will not be possible, of course, unless the expressions x, 7, fulfil certain conditions. Prof. Dixon considers the case in which z# can be so determined that 7 is only subjected to one condition, and finds that then az is a linear combination of the differentia} expressions used in Hamburger’s method of solution. If such a function # can be found, the system /=0, «=a, will have a series of solutions depending onan arbitrary function of one variable, and involving two further arbitrary constants. The next paper, ‘‘On the Fundamental Differential Equa- tions of Geometry,” was read by Dr. Irving Stringham, of the University of California. Dr. Stringham derives the analytical formule for non-Euclidian Geometry by following a procedure indicated by Feye St. Marie, and later discussed in Killing’s ‘* Nicht-Euclidischen Raumformen.” Within an infinitesimal domain in non-Euclidian space, the propositions of Euclidian OcrToBER 12, 1899] NATURE 585 Geometry may be regarded as true; from this fact can be de~ duced a group of equations typified by : da_ f(b) db : dy i ee Ri,)\ da siny ada ROS 7, aa da.” where a, 4, ¢, are the sides of a triangle, and a, B, 7, the cor- responding angles. From these, by appropriate eliminations and transformations, the differential equation (F(a) = — ett — (f(a) can be found for the function # Solving this, we have f(a)=« sinh ©, K and thence can derive the fundamental equations of non- Euclidian measurement. sinh® /sinh a=sinh o /sin B=sinh < /sin 7: K K K This was followed by the communication of a Report on the Problem of Three Bodies, which Mr. E. T. Whittaker was commissioned to prepare at the Toronto meeting. In a general sketch of the results, Mr. Whittaker explained the transformation which has taken place in dynamical astronomy as a result of the researches of Newcomb, \Hill, Lindstedt and Poincaré. Formerly the subject might be said to consist of. two departments—the planetary and lunar theories; now the dis- tinction between these was becoming less prominent, as the Problem of Three Bodies was treated in greater generality. Among the advances referred to were Dr. Hill’s introduction of periodic orbits as a substitute for Keplerian ellipses in the first approximation to the solution, Newcomb’s proof that the problem can be solved by series in which the time occurs only in the arguments of trigonometric functions, Poincaré’s theorem that these series are only asymptotic expansions, and Bruns’ result that the system possesses no algebraic integrals other than those already known. A second paper by Prof. Forsyth, ‘‘On Singular Solutions of Ordinary Differential Equations,” described some properties of the /-discriminant and c-discriminant of an ordinary dif- ferential equation of the first order. The two last papers on the list were ‘*An Application and Interpretation of In- finitesimal Transformations,’’ by Dr. E. O. Lovett, of Princeton University, N.J.; and ‘‘On Fermat’s Numbers,” by Lieut. - Colonel Cunningham. In the absence of their authors the papers were communicated by title, and the session was closed. Looking at the papers as a whole, they were of just that character which makes the B.A. meeting useful to mathema- ticians ; that is, they related not so much to abstruse continuations of well-known theories as to new and little- known subjects, suggestions of improved notations, reports on the recent progress of different branches of mathematics, and generally all those topics for which discussion at a real meeting is more important than the publication of a paper. PHYSICS AT THE BRITISH ASSOCIATION. THE attendance of physicists at Dover was rather smaller than usual, on account of the occurrence of the Volta Cen- tenary celebrations at Como and the simultaneous meetings of the French Association for the Advancement of Science at Boulogne. Several of those who in past years have been leaders in the discussions of Section A were this year conspicuous by their absence. Nevertheless, the papers read maintained a high standard of excellence, and the reports presented indicate that good work is being done by the committees appointed for scientific research. The address delivered by Prof. Poynting, as President of the Section, was the subject of many conversations, not only among physicists but with biologists also ; the existence of the sharp line which he indicated between the psychical and physical methods and the phenomena to which each is applicable, was acknowledged on all sides. The physicists were divided on the question of the danger of too much hypothesis, and especially on the possibility of the propagation of electromagnetic waves in air being due to the air as much as tothe ether. All, how- ever, were agreed in the expression of thanks to the President, proposed by Sir George Stokes and seconded by Sir Norman Lockyer. In a paper on the spectroscopic examination of contrast phenomena, Mr. G. J. Burch described experiments which lend NO. 1563, VOL. 60] great support to the Young-Helmholtz theory of colour-vision. If the eye is fatigued by exposure to a very intense red light, such as sunlight filtered through red screens and focussed on the eye, and a spectrum be then looked at, the red is invisible ; but the rest of the spectrum, green to violet, appears in its ordinary colours. Red-blindness is therefore not accompanied by green- blindness, as Hering’s theory requires. Further experiments on the blue and violet portions of the spectrum have led Mr, Burch to the conclusion that we have separate primary sens- ations for blue and violet, in addition to those for red and green, taking four altogether instead of the three postulated by the Young-Helmholtz theory. The experiments are the more con- vincing because carried out with spectral colours, thus avoiding allerrors due to the impurity of pigment colours. In the dis- cussion on the paper several members took part; Sir George Stokes said experiments led him to believe that lobelia blue is a primary sensation, and Principal Glazebrook suggested that the theory should be tested by colour-matches on a spectro- photometer. Prof. Callendar gave the preliminary results of a research on the variation of the specific heat of water with temperature, which he commenced in Montreal with Mr. H. T. Barnes, and which is now being continued by the latter. The method of experiment consists in allowing water to flow steadily through a narrow tube along which a platinum wire runs axially; on passing a constant electric current through the wire the water finally acquires a steady temperature-difference between the inlet and outlet of the tube, which is measured by platinum thermometers and automatically recorded. Radiation cor- rections are reduced to a minimum by surrounding the tube with a vacuum-jacket, and the electrical energy supplied is measured by observing the current and the potential-difference between the ends of the wire in the tube. The results show that the specific heat of water has a minimum value of 0°995 in the neighbourhood of 40° C., it rises to 1°000 as the temperature falls to 10° C., and continues to rise rapidly as the temperature decreases. On increasing the temperature above 40°C. the specific heat rises to 0°997 at 60°C. Further experiments will be made in the neighbourhood of the freezing point and on either side of it. The committee on electrolysis and electro-chemistry has undertaken the comparison of the variation of electrical con- ductivity with concentration, and the variation of freezing point with concentration for identical very dilute aqueous solutions of electrolytes. The electrical measurements have been success- fully carried out by Mr. W. C. Whetham, but the freezing point determinations, undertaken by Mr. E. H. Griffiths, have been delayed by the discovery of errors arising from the presence of dissolved gases in the solutions. Incidentally Mr. Griffiths re- marked that he was able to measure temperatures to within three or four parts in a million. Dr. R. A. Lehfeldt, at a subsequent meeting, called attention to a flaw in Nernst’s theory of electrolytic solution pressure. According to this theory, when a metal is immersed in an electrolyte ions are torn either from the metal or from the solu- tion according as the solution-pressure is greater or less than the osmotic pressure of the ions in solution. It is usually supposed that the mass of the ions deposited or dissolved is so extremely small that it cannot be detected ; the author showed, however, by considering the electrostatic tension due to the ionic charges, that the amount dissolved should be easily weighable, at any rate in the case of zinc. The stability of an ether containing long, thin, empty vortex filaments was discussed in a communication by Prof. Fitz- Gerald on the energy per cubic centimetre in a turbulent liquid transmitting laminar waves. Lord Kelvin considered this sub- ject in 1887, and concluded that rapid diffusion would make the structure unstable. The author held the opinion (though possibly Lord Kelvin would differ from him) that the turbulency of a sufficiently fine-grained irregularly turbulent liquid would ultimately diffuse so slowly that Lord Kelvin’s investigation could be applied to it. Until the meeting of the Association in 1893, it was generally supposed that the absence of an atmosphere from the moon, and of hydrogen from our own atmosphere, is due to the high average velocity of the gaseous molecules, which is sufficient to carry them beyond the range of the moon’s or earth’s attraction. On that occasion Prof. Bryan demonstrated the incorrectness of this view for the case of the moon, and he has since extended his calculations to the cases of hydrogen and helium in the 586 NATURE [OcToBER 12, 1899 earth’s atmosphere, and of water vapour in the atmosphere of Mars. The method of calculation is to determine the number of years which would be required for the planet to lose from its surface a layer of the gas one centimetre thick at various temperatures. The results show that the earth might retain helium, but would lose hydrogen appreciably at ordinary tem- peratures, and that Mars might retain water vapour at ordinary temperatures. If helium ever existed on the earth’s surface, it must have escaped when the surface was much hotter than at present, whereas a smaller elevation of temperature would cause water vapour to escape from the surface of Mars. Prof. W. F. Barrett described the thermo-electric properties of an alloy containing iron 68°8 per cent., nickel 25'0, man- ganese 5°0, and carbon 1*2._ When a thermo-electric couple is formed of this metal and iron, the electromotive force rises with temperature to 300° C, ; it then remains steady until 500° C. is reached, after which it falls slightly and rises again to 1100° C. ; the fluctuations of electromotive force do not exceed 4 per cent. of the total value. When the alloy forms a couple with nickel the results are similar, but the range of variation is slightly greater. The committee on the heat of combination of metals in the formation of alloys, appointed last year to assist Dr. A. Galt in his experiments on this subject, reported the completion of their work. Only alloys of zinc and copper have been examined, twenty-two in number and containing from 5 to 90 per cent. of copper ; the difference between the amounts of heat evolved by dissolving in nitric acid unit mass of the alloy and corresponding amounts of the mixed metals was taken as the heat of combin- ation of the metals. The results indicate a negative heat of combination for alloys rich in zinc, the numerical value of which is a maximum when the alloy contains 16 per cent. of copper. The formation of an alloy containing about 24 per cent. of copper takes places without absorption or evolution of heat, while for 38 per cent. of copper the heat of combination is a maximum and positive ; beyond this it diminishes to zero for pure copper. In the absence of Dr. Galt and other members of the committee no reply was given to a serious criticism by Prof. Vernon Harcourt, that in the experiments no account was apparently taken of the fact that the products arising from the solution of an alloy in nitric acid are not the same as would be obtained from the mixed metals. In his paper read last year at Bristol, Dr. Galt mentioned that he had made many pre- liminary experiments, and possibly he has examined this point ; if not, the results obtained by the committee will be somewhat vitiated. A preliminary report of the committee on radiation from a source of light in a magnetic field was communicated to the Section, the chief points in which were (1) the discovery that light passing through a magnetic field at right angles to the lines of force suffers absorption (see NATURE, vol. lix. pp 228-9, January 5, 1899) ; (2) the various modified forms of triplet are true magnetic perturbations of the same kind as the normal triplet ; (3) the spectral lines of a substance may be divided into groups such that all members of one group suffer the same kind of perturbation (see NATURE, vol. lix. p. 248, January 12, 1899). The Zeeman effect is attributed to the action of a mag- netic field on the moving ions; recently Mr, C. E. S. Phillips has discovered an apparently cognate phenomenon, which he described in his paper on the production in rarefied gases of luminous rings in rotation about lines of magnetic force. An electric discharge is passed between soft iron electrodes in a Crookes’ vacuum tube; on stopping the discharge and setting up a magnetic field between the electrodes, a luminous ring forms with its plane at right angles to the lines of force and in rotation about the magnetic axis. The direction of rotation is that which would be communicated to negatively charged particles, and is reversed on reversing the magnetic field; the luminosity persists sometimes for a minute, and re- versal of the magnetic field causes it to brighten momentarily. Two explanations of the phenomenon have been given; one is that the rotating matter consists of ions or electrons, and the other that the matter consists of gas particles which have ac- quired a negative charge by contact with the walls of the tube. From experiments of Prof. J. J. Thomson, it appears that neg- ative ions move more quickly than positive, which would account for the greater luminosity of the negative ions when set in rotation, " In a note on deep-sea waves, Mr. V. Cornish endeavoured to trace relations between the amplitude, wave-length, and wind- NO. 1563, VOL. 60] velocity for waves on the surface of deep water. Sir George Stokes pointed out that the amplitude observed is not that of a simple wave, but is the resultant effect of a train of waves of different periods and lengths. At the meeting of the Section on Saturday the visitors fron the French Association at Boulogne were present, and the President extended to them a hearty welcome, which was acknowledged by M. Benoit, as president of the Physical Section of the French Association. A paper was then com- municated by Prof. J. J. Thomson, on the existence of masses smaller than the atoms. He stated that several lines of research lead to a determination of the ratio of the mass of ‘an atom (7) to the charge carried by the atom (e). Among these are electro- lysis, the velocity of charged particles in a magnetic field, and the magnetic deflexion of kathode rays. The two latter methods are comparatively simple, because they depend on the observation of luminous effects, but although they agree with each other fairly well, they furnish a value of %/e which is about 1/1000 of that calculated from electrolytic phenomena. It becomes, therefore, a matter for inquiry whether in the former experiments the atom carries a charge greater than that required by Faraday’s laws, or whether the charge is carried by a portion only of the atom—in other words, whether a smal} fraction of the mass of the atom is detachable which has associated with it a negative charge. The simplest crucial experiment is obtained by determining separately either 7 or e, and the author has devised a means of measuring the latter quantity. Hetakes a negatively charged metal plate supported horizontally ; below this and parallel to it is a very large perforated metal plate, the whole being in rarefied gas at a pressure of about 1/100 mm. mercury. When ultra-violet radiation is directed through the perforated plate to strike the upper plate the latter is discharged, the discharging particles moving along straight lines normal to the two plates. If a magnetic field be now excited with its lines of force parallel to the plates, the particles describe curved paths which are in fact portions of cycloids. When the plates are near together the particles which leave the upper one strike the lower one; if, however, the plates are separated further, the vertex of the cycloidal path comes between them, and the particles do not reach the lower plate, so that the dis- charge ceases. In the actual experiment there is a gradual, but not abrupt, change in the rate of discharge, possibly because all the particles do not start from the surface of the upper plate. From observations on the distance apart of the plates when the change in the rate of discharge commences, the form of the cycloidal path is determined, and the results show that the smaller value of m/e is applicable to this case and to that of illumination by kathode rays. Further, the amount of electricity discharged by the illuminated plate per second is proportional to the number of particles between the plates, to the charge carried by each (e), and to the velocity of the particles. The last-named quantity is measured by a method due to Prof. Rutherford, so that if the total number of particles in the space is known the value of e can be determined. To count the particles use is made of the fact that they serve as nuclei for the formation of drops out of a condensing vapour, each particle giving rise to one drop, Leta known amount of air of given humidity be suddenly and definitely expanded in the presence of the particles, and observe the rate at which the drops fall ; this rate gives the size of the drops, andhence their mass, and since the whole mass of water deposited is known, the number of drops is thus determined. For negative charges the ratio m/e is independent of the nature of the gas, whereas for positive charges its value varies from one gas to another, and corre- sponds generally with the values given by electrolytic phenomena. Prof. Thomson considers that electrification con- sists in the removal from the ‘‘atom”’ of a small corpuscle with which the negative charge is associated; the remaining large portion of the mass is positively charged. This view is supported by Prout’s hypothesis that the mass of an atom is not invariable, and by the evidence derived by Lockyer and others from spectroscopic observations. In the discussion which followed upon Prof. Thomson’s paper, M. Broca described spectroscopic observations of a spark obtained between two platinum electrodes 4 mm. apart in a Crookes’ vacuum tube; the spectra of the regions near the electrodes and the space between them were not alike. Prof. Riicker drew attention to Schuster’s experiments, in which the spectrum of a substance not present in the material examined sprung into being in the arc itself. He believed matter to be a EE OcToBER 12, 1899] DEAT Role 587 complicated collection of units themselves similar. Sir Norman Lockyer said that if we accept the view that elements of smallest atomic weights should appear first in the spectrum of a hot star, we must assume the existence of forms of calcium, magnesium, iron and copper having atomic weights which are submultiples of those assigned to them in ordinary chemistry. Further, the division of the spectra of certain elements into series of lines by Rydberg, Runge and Paschen, and others indicates that the atoms of these elements are complexes ; we shave, therefore, no reason to suppose that the so-called ‘‘ atoms” are not dissociable at high temperatures. Prof. Oliver Lodge thought the investi- gations of Prof. Thomson might turn out to be the discovery of an electric inertia, and lead to a theory of mass. Several speakers expressed their pleasure in receiving the members of the French Association. In the very short time remaining after the discussion on the previous paper, Prof. Oliver Lodge gave a short account of the controversy respecting the seat of Volta’s contact force. On Monday the Section was subdivided for papers on mathe- matics and meteorology respectively. In the latter department, oyer which Sir George Stokes presided, a formal report was presented by the committee on solar radiation. Dr. van Rijckevorsel read a paper in which he traced an intimate con- mection between the activity of sun-spots and the temperature. The committee on seismology presented a voluminous report on their work, from which it appears that twenty-three stations are now equipped with recording seismographs, and registers have been received from ten of these. Notes on these registers occupy a considerable portion of the report; the rest of the report is abstracted from articles which have already appeared in NATURE (February 16 and March 1, 1899). Mr. T. F. Claxton communicated the preliminary results of a year’s work with the seismograph at Mauritius. The diurnal waves are of greater amplitude than at any other observing station, and there is a well-marked bi-diurnal effect possibly connected ‘with baro- metric pressure. Rapid and large changes of the vertical have occurred on several occasions, in addition to a constant gradual change. Air tremors have given trouble at night. The earth- quake effects have been of disappointingly small amplitude, and it is suggested that the ocean may act as a damper to earth- quake shocks. Mr. A. L. Rotch gave an interesting account of the progress achieved during the past year at Blue Hill, Massachusetts, in the exploration of the air with kites. The Hargrave kite with curved surfaces has been found more satisfactory than any other form, and the meteorograph records temperature, humidity, height and wind. Temperature is found to decrease at first with elevation, and afterwards to increase again. The heights attained were on the average greater than in previous years. he author mentioned that the United States Government has arranged for daily simultaneous observations at two heights in the case of a number of stations, the kite being used for the high-level observations. The results are not quite satisfactory, because kites could not be sent up on some days ; it is suggested ‘that on such occasions a captive balloon be employed. Prof. Thomson hoped that the variation of atmospheric electric poten- tial would be investigated by means of kites. Prof. G. H. Darwin regretted that on account of the non-existence of a ‘Government meteorological observatory, this country is very backward in the adoption of recent methods of meteorological research. Ina subsequent paper Mr. Rotch gave an account of the first crossing the Channel by a balloon, by Dr. Jeffries and M. Blanchard in January 1785. The former was a Harvard graduate in medicine, who settled in London, and the latter a French pro- fessional aéronaut. The expedition was of a scientific character. A description of the hydro-aérograph, an apparatus invented by Mr. F. Napier Denison for registering small fluctuations of level of the American lakes and simultaneous small changes of air-pressure, was read by Mr. W. N. Shaw. The ap- paratus is designed to study more minutely an observed effect of barometric changes on the surfaces of the great American lakes. The Ben Nevis committee presented the usual summary of their records, and stated that the conclusions arrived at last year with reference to the effects of approaching cyclones and anti-cyclones on the two observatories are supported by the examination of later records. The committee on meteoro- logical photography reported having obtained photographs of some rare forms of cloud and some studies of lightning flashes; the structure of thunderclouds appears to resemble ‘two parallel discs of cloud, with lightning flashes passing be- ‘tween them or from one face to the other of either cloud. NO. 1563, VOL. 60] On Tuesday, Prof. Threlfall described a portable gravity balance, designed by Prof. Pollock and himself, for the measurement of small differences in the intensity of gravity from place to place. It consists of a light wire attached near one end to the centre of a horizontally stretched and twisted quartz fibre, the moment of the weight of the wire just balancing the torsional moment of the fibre. The wire is only just in stable equilibrium, and the torsion of the fibre is noted when the wire is adjusted to coincide with the axis of a microscope carried on the frame of the apparatus. The instrument can now be relied upon to rT part in 500,000, but the accuracy of single readings is greater than this. It has been severely tested by much travelling on the Australian coast. The committee on electric standards reported that Profs. Ayrton and J. V. Jones have now completed the plans and specifications for the ampere balance to be used in constructing an ampere standard. The committee will consider the pro- posals of Prof. Callendar for the construction of a standard platinum thermometer in terms of which all other platinum thermometers can be compared. The report contains the results of a determination of the coefficient of expansion of. porcelain, by Mr. T. G. Bedford, which was undertaken in order to com- pare the scales of temperature and platinum thermometers of air. Prof. Callendar opened a discussion on platinum thermo- metry, in which he advocated the adoption of the variation of resistance of platinum as a basis for a practical scale of temper- ature. _He suggested the construction of a standard thermo- meter from a particular sample of platinum wire, and the use of a parabolic difference formula for the determination of temper- ature by its means. The difference-coefficient may be obtained by using as a secondary fixed point the boiling point of sulphur (444°53° C. at normal pressure). Dr. J. A. Harker described the method used, and Dr. Chappuis the results obtained, in a comparison of platinum and nitrogen thermometers at the International Bureau of Weights and Measures at Sévres. The results agree fairly well with those of Callendar and Griffiths in the comparison of the air and platinum thermometers. In the discussion Mr, E. H. Griffiths advocated the use of the platinum thermometer on the ground that only three readings are necessary in order to standardise any instrument. Prof. Carey Foster was of opinion that the electrical method would furnish a good intermediate standard ; for absolute values, however, the gas thermometer must be used, because there is no theory of the variation of electrical resistance with temperature and only an empirical knowledge of it. Prof. Burstall described experi- ments supporting the proposals of Prof. Callendar, Principal Glazebrook thought that, before taking platinum as a standard, experiments should be undertaken to ascertain whether it is superior to other metals, for instance gold. Dr. Chree said that some platinum thermometers purchased by the Kew Observatory had exhibited curious tricks, and were far from satisfactory, because the reasons for departure from accuracy were numerous and not always discoverable. In the case of mercury thermometers the zero certainly alters, but the change has a known cause, and can be allowed for. Prof. Threlfall remarked that for rapid and accurate work the platinum thermometer alone could be used ; the enormous heat- capacity of a mercury thermometer rendering it quite unservice- able. Mr. W. N. Shaw thought the thermo-electric couple methods, upon which the Germans are concentrating their attention, ought to be compared with the platinum thermometer before deciding upon a standard. In reply, Prof. Callendar said that methods based on the use of a thermo-electric couple are not sensitive at low temperatures. On Wednesday, Dr. L. A. Bauer described the arrangements made by the United States Coast and Geodetic Survey for the proposed magnetic survey of the United States and Alaska, and expressed a hope that the Canadian Government would consider the possibility of a simultaneous survey of Canada. Dr. Bauer also described the results of a magnetic survey of Maryland. Dr. E. P. Lewis, in a paper on the spectral sensitiveness of mercury vapour in an atmosphere of hydrogen, described the appearance and intensity of the spectrum of a mixture of hydrogen and vapour of mercury in varying proportions. Mr. J. Gifford, who has measured the angles of prisms of quartz and calcite, and the corresponding minimum deviations for the mean of the sodium lines, at various temperatures, gave an account of the variation of refractive index with temperature in these cases. The proceedings of the Section closed with votes of thanks to the president and secretaries, proposed by Prof. Poreyte and seconded by Prof. Reinold. 588 ‘NATURE [OcroBeER 12, 1899 UNIVERSITY AND EDUCATIONAL INTELLIGENCE. Oxrorp.—The following are among the lectures and practical courses announced for the present term :—General Pathology, Sir J. Burdon-Sanderson ; The Chemical Processes of the Body, Prof. F. Gotch; Elementary Physiological Chemistry, W. Ramsden ; Practical Histology, G. Mann ; Elementary Medicine. W. Collier; Minor Surgery, A. Winkfield ; Human Osteology, Prof. A. Thomson; Analytic Theory of Plane Curves, and Synthetic Theory of Plane Curves, Prof. W. Esson ; Elementary Mathematical Astronomy, Prof. H. Turner ; Physical Crystal- lography, Prof. H. Miers; Practical Crystallography, H. Bowman ; Electricity and Magnetism, Prof. A. Love; Theory of Numbers, Prof. E. Elliott ; General Morphology, and Varia- tion Inheritance and Natural "Selection, Prof. W. Weldon ; Ex- perimental Physics, Prof. R. Clifton; Structure of Simple Machines, Rev. F. Jervis-Smith; Silicon and Boron Com- pounds, Prof. W. Odling ; Subjects of the Preliminary Ex- amination in Chemistry, Dr. W. Fisher; Organic Chemistry, J. Watts; Physical Chemistry, V. Veley; Metabolism, J. Haldane; Muscular Activity, Prof. F. Gotch; Physiological Physics, G. Burch; Physical Geology, and Jurassic Fossils, Prof. W. Sollas ; Elementary Botany, Prof. S. Vines ; Clas- sification of Mankind by Race, Language and Civilisation, Prof. E. Tylor ; Bacon, and the Organon of Aristotle, Prof. T. Case; Mental Evolution, G. Stout; Inference and Scientific Method, J. Cook Wilson. CAMBRIDGE —Mr. John Sealy Edward Townsend, who entered the University as an Advanced Student in Physics, was on October 9 elected to a Fellowship in Trinity College. Dr. W. E. Dixon, late Salters’ Research Fellow in Pharma- cology, has been appointed Assistant to the Downing Professor of Medicine. Dr. L. Humphry has been appointed Assessor to the Regius Professor of Physic. A Scholarship of 50/. in Natural Science will be open for competition at Downing College to members of the University of less than four terms’ standing on Monday, November 27. Applications are to be made to the Tutor. Studentships for research have been awarded at Emmanuel College to R. G. K. Lempfert and B. W. Head. A GENERAL meeting of Convocation of the University of London was held on Tuesday to receive an interim report from the special committee appointed on June 27 to make represent- ations to and to confer with the London University Commis- sioners, the Senate, and other bodies with reference to the scheme of the Royal Commission. On the subject of faculties contemplated under Section 10 of the Schedule of the Uni- versity of London Act, the special committee made various recommendations, among which the following may be noticed :— There should be only one faculty of science with adequate representation on the Senate and the Academic Council. Engineering should be a distinct branch of the one faculty of science and not a separate faculty, but degrees should be given in engineering bearing a distinctive name. If it should be thought expedient to constitute a distinct branch of the faculty of science for any other scientific profession, there is not, in the opinion of the committee, any present occasion for giving a distinctive name to degrees to be taken in that branch. If, contrary to the opinion of the committee, the subjects of the faculty of science should be divided by the commissioners, for electoral purposes, into several faculties, the committee hope they may be afforded an opportunity of giving further consider- ation to the principles upon which such division should be effected, especially in connection with the effect which the division would have upon the University examinations and degrees. After discussion it was decided ‘‘that the report be received subject to the reconsideration by the committee of such points, if any, as this house may deem advisable.” SOCIETIES AND ACADEMIES, PaRISs. Academy of Sciences, October 2.—M. van Tieghem in the chair.—The Mayor of Chantilly informed the Academy that he inauguration of the statue erected to the Duc d’Aumale would ke place on October 15.—Orbit of the shooting star of August ie by M. J. Comas Sola. This meteor, which was a very bright one, was observed at the Observatory of Catala, had a relative NO. 1563, VOL. 60] direction nearly east to west, disappearing near a-Capricorn. Its absolute velocity was 50 kilometres per second. A similar meteor was observed on August 28 at 7.45, but of smaller lustre. —On the identity of solution of certain problems of elasticity and hydrodynamics, by M. Georges Poisson. In a note presented to the Academy on May 2, 1898, M. Maurice Lévy remarked that in problems of elasticity in two dimensions the distribution of the pressures is independent of the value of the elastic coefficients. In the present note it is shown that in this case the determination of the pressures may often be reduced to the study of the permanent motion of a liquid. —On two chloro- bromides of tungsten, by M. Ed. Defacqz. In an attempt to prepare tungsten hexabromide, tungsten hexachloride was sealed up with liquid hydrobromic acid in excess, and the whole heated at 70° for four hours. The resulting product was not the desired hexabromide, but a chlorobromide having approximately the composition WCl.3WBr,. Ina second similar preparation the tube was not heated, but left for three days at the temperature of the laboratory ; the substance obtained was another chloro- bromide, represented by the formula WCl,.WBr,.—On copper hypophosphite and its decomposition by precipitated palladium, by M. R. Engel. Aqueous solutions of copper sulphate and barium hypophosphite are mixed in equal molecular proportions, the solution filtered, and the copper hypophosphite precipitated in the crystalline form by the addition of alcohol in excess. The solution of the salt is decomposed in a remarkable manner by the addition of precipitated palladium, copper being thrown down and hydrogen gas evolved according to the equation Cu(PO,H.).. +2H,O=Cu + 2H,PO,+ Ha, no copper hydride being formed. In the absence of palladium the copper hypophosphite is decomposed differently by heat, copper hydride being first formed, and then metallic copper, phosphorous and hypophosphorous acids.—Salicylic and ara- oxybenzoic aldehydes and salicylhydramide, by MM. Delépine and Rivals. A thermochemical paper.—On a double mon- strosity observed in the blastoderm of a fowl’s egg in the course of formation, by MM. Bonmariage and Petrucci.-— Completion of some observations on the Alps of the Vaudois, by M. Stanislas Meunier.—On an aérial voyage of long duration, from Paris to the Mediterranean, carried out on September 16 and 17, by M. Gustave Hermite. —Barometric deviations on the meridian of the sun on successive days of the tropical revolution of the moon, by{M. A. Poincaré. CONTENTS. PAGE Verworn’s ‘‘General Physiology.” By W. B. Hardy . dk Gita CEES oc 0 0) SOS Our Book Shelf :— Hopwood : ‘ Living Pictures ” 567 Pullen: ‘‘ Tables and Data” . 567 Letters to the Editor :— Halo Round a Shadow.—A. Mallock : 567 The Skull of Hatteria.—Prof. W. Blaxland Benham 2% a elev. The Best Education for an Engineer. ‘By W.E. A. 568 Research Work and the Opening of the Medical Schools, By Ea Wile : 569 Dark Lightning Flashes. (J//ustrated.} By Dr. William J. S. Lockyer ess 57° Notes c 574 Our Astronomical Column:— Comet Giacobini (1899 E) . 577 Holmes’ Comet (1899 @) 577 The Rotation of the Sun 577 The Polaris Multiple Star one : nae 577 Astronomical Camera Doublets. . . . . -... . 578 Observation of Leonids es Te The Freedom of the City ‘of Manchester. By We. 1. 578 Visit of the Institution of Electrical Engineers to Switzerland, August 31 to September 8. By Prof: Richard ThrelfallMRIRGS.. 9: . . © = ee To The British Association :— . Section K.—Botany.—Opening Address by Sir George King, K.C.I.E., F.R.S., President of the Section : 5S Mathematics at the British Association . 584 Physics at the British Association 585 University and Educational Intelligence 588 Societies and Academies. . 0) OND 588 NATURE 589 THURSDAY, OCTOBER 109, 1899. ELECTRO-MAGNETIC THEORY. Electvo-magnetic Theory. Vol. ii. By Oliver Heaviside, Pp. xvi + 542. (London: The Electrician Co., Ltd.) HIS interesting work, the first volume of which appeared some five years ago, well sustains Mr. Heaviside’s reputation as an original investigator, and even when we do not agree with his procedure, we must admire his fertility of resource and the skilful manner in which he develops his methods. Although we are more than once warned that the treatment is not formally or logically arranged, as is indeed the case, Mr. Heaviside has nevertheless, in essentials, admirably arranged his matter, so that we are led on by gentle steps from comparatively simple to more complex problems. The book may be regarded from two distinct points of view. Firstly, without inquiring too closely into the validity of the mathematical methods employed, we may consider the work from a physical point of view as a mathematical theory of the propagation of plane electro- magnetic waves in conducting dielectrics, according to Maxwell’s theory, oras the theory of the propagation of waves along wires. Secondly, we may consider the book from a purely mathematical point of view as an introduction to the theory of generalised differentiation, divergent series, and Bessel’s functions, viewed, however, for the most part through physical spectacles. The book opens with a discussion of the age of the earth, in which Prof. Perry’s results are explained and contrasted with those of Lord Kelvin. Then follows a discussion of the equations where V and C are the voltage and current, R and S the resistance and permittivity per unit of length, and / stands d dt some detail, and it is very noticeable how easily terminal conditions are dealt with by Mr. Heaviside’s methods, and in this respect they have a great advantage over Fouriers method. The more general equations dV _ Be =(R+L¢)C, for A large number of problems are considered in 2G 2 Te SAN where L is the inductance and K the leakance, as Mr. ‘Heaviside terms it, per unit of length, are next con- sidered. These in the case where 1/R, 1/L, K and S all vary as the 7th power of the distance from x=o lead to Bessel’s functions. As before, a great variety of interesting and important questions are dealt with, and Mr. Heavi- side is careful to explain that these are not mere mathe- matical exercises, but that the formule apply to cylindrical electro-magnetic waves. The case of R, L, K, S, constants is discussed at some length, and owing to the application of the results to practical questions concerning telegraph and telephone cables they should be kept in mind by “practicians.” Mr. Heaviside has for long been preaching in the wilderness on this matter, but his labours will bear fruit one day, and we trust that when the day comes it will not be a case of “tulit alter honores,” as has happened to other men in other matters. NO. 1564, VOL. 60] Some sections are devoted to discussions of the experi- ments of Dr. Barton and Dr. Bryan, of spherical waves, and, with some reserve, to the experiments of Hertz and Lodge. The sections on spherical waves have, as is pointed out by the author, a practical application in wire- less telegraphy. Some rough, but interesting, curves showing the progress of a wave under various circum- stances conclude the physical portion of the work. Passing on to the mathematical aspect of the book, operational methods are freely employed, and their reduction to algebraical form leads us at an early stage of the work to the question of fractional differentiation. This is a subject which has frequently occupied the attention of mathematicians, and two main modes of pro- ceeding have been proposed, one taking e”, the other x” as the fundamental symbol ; the first method was employed by Liouville and Kelland, the second by Peacock. Both methods find formule: which are certainly true when the index of the operating symbol is an integer, and for the case of the index or fraction both appeal to the principle of the permanence of algebraical forms. If both methods produced the same result in every case all might be well, but most unfortunately this is not so, at least without some further assumption, and it is a ques- tion beset with difficulties which system, if either, is to be considered the true one. Mr. Heaviside’s method evades rather than elucidates the difficulties. He re- quires to find the value of #1, where p = f,and tis that é function of ¢ which is zero before and unity after =o. To effect this he takes a suitable physical problem, and, solving symbolically, obtains a solution involving !1 ; then by another method he finds a solution free from operators ; a comparison of the two gives f/1=(m?)™'. This is the same value as is given by Peacock’s method, but not that which is given by Liouville’s and Kelland’s without further assumption. In Chapter vil. another way, on the same lines as before, is given of finding this result, and the remark is added, “I do not give any formal proof that all ways properly followed must neces- sarily lead to the same result.” It is much to be re- gretted that no hint is -given on this point, for, granting that there is a theory of fractional differentiation, the way to be properly followed is the essence of the whole matter. Some of Mr. Heaviside’s methods of dealing with series in Chapter vill. are also open to some objection ; he more than once tests the equivalence of two series by giving the variable numerical values and seeing if the two series give the same result. This may be an “excursion to the borders of the realms of duplicity,” but scarcely to those of “fearful rigour.” It would seem, indeed, from many passages in the book, that Mr. Heaviside considers rigour in mathematics to be of somewhat minor im- portance ; for instance : “You have first to find out what there is to find out. How you do it is quite a secondary consideration.” If this advice were to be generally followed, mathe- maticians would no doubt jump many gates in their endeavours to reach the goal on the other side, but whether or no they would not at times land in a quag- mire may be open to doubt. iE 599 ‘NATURE [OcToBER 19, 1899 Mr. Heaviside’s treatment of Bessel’s functions is in- teresting and suggestive, but the lack of formal arrange- ment is here severely felt; it is not always easy to distinguish clearly between what is proved and what is experimentally assumed to see how it goes as Mr. Heaviside puts it. The student who is previously un- acquainted with the properties of these functions will probably find difficulty in following some of the equations written down without proof. In the equation for Ky (gx), p. 226, for example, all the information given about y (Euler’s constant, but not distinguished as such) is ‘““where y = 0°5772 is a certain constant introduced to make Ky (g¥) vanish at infinity”; certain of the con- jugate relations are also without proof, but these possibly are left as exercises for the student. The work is nevertheless one which will well repay careful attention.’ As has been remarked by Prof. De Morgan : “The history of algebra shows us that nothing is more unsound than the rejection of any method which naturally arises, on account of one or more apparently valid cases in which such methods lead to erroneous results. Such cases should indeed teach caution, but not rejection.” Mr. Heaviside is much to be congratulated on the light he has thrown on difficult and perplexing questions in both physics and mathematics, and also for calling the attention of mathematicians to a powerful, but somewhat neglected, weapon. C. S. WHITEHEAD. OUR BOOK SHELF. Catalogue of the Lepidoptera of Northumberland, Durham and Newcastle-upon-Iyne. Part 1. By J. E. Robson. Nat. Hist. Trans. of Northumberland, Durham and Newcastle-upon-Tyne, Vol. xii. Part 1. Pp. 195. THE present instalment of this important catalogue in- cludes the butterflies, together with such of the moths as are comprised in the Spingina (hawk-moths), Bom- bycina, and WVoctuina. In his classification the author thus far follows Mr. Barrett's monograph of the British Lepidoptera, to the unpublished portions of which he has been supplied with references by Mr. Barrett himself. Whatever faults there may be in the scheme of classifica- tion in question, and the nomenclature employed therein, the adoption of a uniform system by different writers is highly desirable ; and we, therefore, consider that Mr. Robson has been well advised in the course he has adopted. As the author has had the advantage of the co- operation of all the local collectors of repute, his work may be regarded as a thoroughly up-to-date account of the Lepidopterous fauna of the northernmost counties of England. And how different this fauna is from that of the midland and southern counties may be gathered from a glance at the portion devoted to the butterflies. The common Brimstone Butterfly, for example, is only known in the area treated of by two or three stragglers, its normal range not extending northwards of South York- shire. Much more remarkable, however, is the circum- stance that certain species of butterflies, such as the Comma and the Red Admiral, which were once common in the two counties, have for the last forty years been extremely scarce, although the second of the two men- tioned has once again become a familiar object since 1893. It would be interesting to know the reason why so many of these insects left the district during the NO. 1564, VOL. 60] sixties ; but on this point the author is silent. On the other hand, as might perhaps have been expected, migratory species, such as the Clouded Yellow and the Camberwell Beauty, which visit England at uncertain intervals in larger or smaller numbers, commonly travel into the northern counties ; the author remarking of the last-named insect that it “visits these counties on most of those rare occasions when a wandering horde strikes our shores.” Of the moths, it must suffice to say that the Death’s-head has occurred in both counties, and there is reason to believe has bred in them, but that the stock is probably maintained by immigration from the south. The foregoing instances demonstrate that Mr. Robson’s work is very far from being a mere dry catalogue ; and that it really teems with interesting observations on the life-history and distribution of all the species recorded. If the sequel be maintained at the same high level, the complete catalogue ought to prove a very important con- tribution to entomological literature. R. The Process Year-Book for 1899 (‘ Penrose’s Pictorial Annual”). Edited by William Gamble. Pp. viii + 108. (London: Penrose and Co., 1899.) THISs is the fifth year’s issue of this most excellent review of the graphic arts, and the editor, together with all his co-workers, are to be congratulated on the production of such a handsome and interesting volume. As in former years, most of the articles are written by those who are at work in some line of process work, and as these are by no means few in number, the reader is made acquainted with a great amount of experience which may help him to success in the future. The feature of the book is undoubtedly the beautiful illus- trations, which bring home to the reader the high state of excellence that the art of reproduction has reached at the present day. All kinds of subjects, from a stellar cluster down to an orchid, are illustrated, and these serve as types for showing the results obtained by the working of different processes. The high order of merit attained should not only render the book a valuable aid to the process worker and others interested in the art of reproduction, but should find many other friends who would delight to possess such a charming collection of high-class illus- trations. Mathematical Tables. W. Haldane Gee. and Co., Ltd., 1899.) THIS set of useful tables ina compact form are abstracted from the compilers’ larger volume of “ Mathematical and Physical Tables.” The idea of this present issne is to place before students tables which are suitable for the class and laboratory, and which give sufficient accuracy for such computations. ' To sum up the contents, we have four place logarithms and antilogarithms, natural sines, cosines, and tangents, with interpolation to 1’. Logarithmic sines, cosines, and tangents with differences also to 1’. Tables of squares, exponential functions, weights and measures, and finally a table of conversion for the last mentioned. By James P. Wrapson and W. Pp.. 28. (London: Macmillan Opinions et Curiosites touchant la Mathématique. By G. Maupin. (Paris: Carré et Naud, 1898.) THis is a collection of curious ideas and essays, which the author has encountered in the course of much heterogeneous reading in ancient scientific works, in which there has been found any reference however remote to mathematical thought. Paradoxes and ab- surdities alone seem to be considered worth inclusion ; the book is of little or no use as a contribution to the history of mathematics. OcToBER 19, 1899] NATURE 591 BEES LO LTTE FOTO Ke The Editor does not hold himself responsible for opinions ex- pressed by hits correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for this or any other part of NATURE. No notice ts taken of anonymous communications. | Peripatus in the Malay Peninsula. My friend Mr. Richard Evans, of Jesus College, Oxford, now in the Malay Peninsula with the Skeat Expedition sent out by the University of Cambridge, writes to me that he and | _ Inde : | the same time in several papers, the latest one having been subsequently other members of the expedition have discovered Peripatus. His letter, written from Aring, Kalantan, and dated August 27, states that he had found two specimens about three months previously. The locality is given as ‘‘one of the mountains here.” For some months after this discovery no further specimens were found, in spite of much searching. A little before the date of his letter, however, Mr. Laidlaw, of ‘Cambridge, had found five and Mr. Evans six additional specimens, thus bringing up the number to thirteen. The eleven specimens which were obtained last were found in two groups of five each, while a single individual was discovered by itself in the rotten tree in which one of the groups occurred. The individuals of a group differed much in size, although each group was probably a brood. The colour of the specimens is chocolate-brown above with numerous small pale spots, the under-surface being pinkish yellow with a nearly white spot between the feet of each pair. The number of pairs of feet varies from twenty-three to twenty-five, the latter number occurring in the largest and presumably the oldest specimens. Mr. Evans has asked me to embody these facts in a note to Narure, and I feel sure that they will be of great interest to all naturalists. EpwarD B. POULTON. Oxford, October 13. Dark Lightning Flashes. THE paper by Mr. A. W. Clayden, referred to in my lecture from which Dr. Lockyer quotes (p. 570 ave), is entitled ‘‘ Note on some Photographs of Lightning and of Black Electric Sparks,” and is to be found in the Praceedzngs of the Physical Society, vol. x. p. 180, having been read on June 22, 1889. The author’s photographs were exhibited at the meeting, but were not printed with the paper. The following extract shows that some of Mr. Clayden’s observations were very similar to those described by Dr. Lockyer. He photographed some electric sparks of different intensities, *‘and before developing the plates exposed them to the diffused light from a gas flame. The brilliant sparks then yielded images which may either be called normal with a reversed margin, or reversed with a normal core. The fainter sparks were completely reversed. . . . The reversal seems to spread inwards as the exposure to diffused light is increased.” If the section of a flash is approximately circular, the luminosity would naturally be greatest along the middle, gradually falling off towards the edge. It was of course known long before the date of Mr. Clayden’s paper that the bright parts of a photograph might be reversed by the action of diffused light before development (Sutton’s “Dic. of Photography,” edition of 1867, p. 299). I think it hardly possible that any lightning flash would be sufficiently brilliant to give a photographic image with a dark core and bright edges—Nos. 5 and 6 of Dr. Lockyer’s list. The image of the sun itself is not generally reversed, unless with comparatively long exposure. The picture in the Strand Magazine (vol. xiil. p. 44, Fig. 10), which I understand to be the only apparent example of this class of reversal which Dr. Lockyer has met with, seems to me, from considerations of perspective, to represent beyond question merely a close double flash, two connected discharges having taken the same path through a moving body of air. Dr. Lockyer’s convincing article has no doubt finally dis- posed of the dark flash as an objective reality, It is to be hoped that so-called ‘‘ ribbon lightning” will soon follow in its footsteps. SHELFORD BIDWELL. NO. 1564, VOL. 60] Heredity and Variation. THE interesting suggestion made by Prof. Adam Sedgwick in his Dover address—to the effect that variability has decreased and heredity increased, so to speak, as evolution has progressed—leads me to call attention to the work of certain other writers. Prof. Bailey, of Cornell University, in his work ‘‘The Survival of the Unlike” (Macmillan) argues in detail for a similar view, z.e. that heredity has been gradually ““acquired,” while variability has been reduced. His book deals largely with evidence from plants. He stated the view earlier in certain papers. Moreover Prof. Williams, of Yale University, independently took up a like position at about read and discussed before the Society of American Naturalists at Ithaca, N.Y., December 1897, and subsequently printed in Sczence.1 The point of view has become fairly familiar to American biologists. Indeed the editor of Sczence has referred to it as one of the two most important recent suggestions in the theory of evolution. As Prof. Sedgwick does not refer to these writers—though he may intend to do so in the fuller discussion which he promises—his readers to whom the sug- gestion appeals may find it worth while to look into them. The work of Prof. Bailey—who is a natural selectionist among botanists !—is remarkable from other points of view as well. Oxford, October 10. J. Mark BALpwWIn. Phosphorescent Earthworms. In a recent issue of NATURE (during May of the current year) Mr. Beddard, in referring to the phosphorescence of Microscolex (Photodrilus) and of Adlolobophora foetida, suggests that this phenomenon is exhibited by the slime secreted by the epidermis. Will you allow me to mention my observation on a New Zealand worm that indicates that the matter is worthy of re-investigation ? Our large white earthworm (Octochoetus mudtiporus) has a milk-coloured ccelomic fluid of very great tenacity ; it can be drawn out into strands, and soon hardens on exposure to air. In the dark, when the worm is handled, this fluid is discharged abundantly from the dorsal pores and from the mouth, which it reaches through the ‘‘ peptonephridia” opening into the buccal cavity. The fluid is brilliantly phosphorescent when freshly discharged, and the fluid sticks to one’s fingers very persistently ; but it soon loses its phosphorescence. I wish here merely to point out that the luminosity is due to the ccelomic fluid in O. mz/t- porus, and I believe that further examination will show that the same is true of 4. foettda. The fluid in O. mzltzporus contains numbers of ‘‘ elaocytes,” which are present also in 4. foe/zda and other European worms; but in the New Zealand worm they are colourless, not yellow. | A very remarkable kind of corpuscle is also present, viz. a cell containing a threadlike structure not unlike those described by Goodrich in an enclytroeid a few years back. I am now en- deavouring to locate the phosphorescence—that is, to ascertain which of these two cells is the seat of the phenomenon. Dunedin, N.Z., August 5. W. BLAXLAND BENHAM. MEETING OF THE INTERNATIONAL METEOROLOGICAL COMMITTEE. HE Committee met at St. Petersburg from September 2-7 ; the meeting was a small one, only about half of the members being present. It was opened by the Grand Duke Constantine, who delivered an interesting address, in which he specially referred to the service rendered to meteorological science by A. Kupffer, the founder of the Russian climatological organisation. The reports of the various sub-committees were read and considered, and the following are the principal resolutions arrived at :—On the report, by Prof. Riicker, upon ter- restrial magnetism and atmospheric electricity, it was decided that the sub-committee should be maintained as a distinct organisation, under the direct supervision of the International Committee. In reply to a question by 1] regret that absence from my library makes it impossible for me to give the exact references to his papers and to Prof. Bailey’s. 592 WAPORL [OcroBER 19, 1899 General Rykatcheff, director of the Russian Meteor- ological Service, the Committee recommended that meteorological institutions should take part in obsery- ations of earthquake phenomena. With regard to Ant- arctic exploration, the Committee expressed the opinion that it is highly desirable (1) that the results of these explorations should be completed by data from the observatories already existing in the southern hemisphere, and by those made on board vessels traversing the southern oceans; (2) that new meteorological stations should be established in the southern part of the Ant- arctic regions, and especially that magnetic observations should be organised ; (3) that magnetic determinations over the whole globe should be made simultaneously with those made during the expeditions. With reference to the valuable researches of Dr. Hildebrandsson relating to the great centres of action of the atmosphere (which have already been noticed in our columns), the following resolution was adopted :—“ The Committee appreciates the high interest attached to observations made in a regular manner in different regions which seem to possess special importance as to our knowledge of the general laws of the motions of the atmosphere.” Profs. v. Bezold and Mascart drew attention to the preposed establish- ment of a very complete meteorological and magnetical observatory at the Azores by the Prince of Monaco, assisted by Captain Chaves, of the Portuguese navy, who has entirely devoted himself to the realisation of this undertaking. On the question of the calculation of daily meteorological means, it was decided that if the exact formula a Bier) 237224) is not adopted the midnight observation should be taken into account at the end of the day, as is already done at most stations, according to the formula I+2+3.-.. +24: 24. On the proposal of Dr. Hann to publish tables of diurnal range of temperature for each country in a special form, the Committee, while appreciating the interest and importance of the proposal, expressed its opinion that, as the question possessed a general bearing, it should be examined by a sub-committee, which should determine the form of table to be adopted by all countries. On the subject of the importance of actinometric obsery- ations, also brought forward by Dr. Hann, the Committee expressed the hope that the sub-committee for terrestrial and solar radiation would present a report upon that subject at the next International Congress. M. Violle submitted a note on the various methods employed for actinometric measurements. On the proposal of Dr. Pernter as to the desirability of the restriction of observ- ations with the wet-bulb thermometer and the multipli- cation of observations with the hair hygrometer, the Committee came to no decision, pending the presentation of a full report upon the question. Dr. Paulsen, director of the Danish Meteorological Institute, drew attention to the importance for weather prediction of the laying of a cable between Iceland and Europe, towards which the Danish Government and the Great Northern Telegraph Company were prepared to make a considerable annual subvention. The Committee fully recognised the im- portance of the proposal, and expressed its hope of the ultimate success of the project. Profs. Neumayer and v. Bezold made a proposal relative to the publication of an international periodical weather report (recently re- ferred to in our columns), which should contain ten-day means from about a hundred stations. The Committee was of opinion that it would be desirable that a definite plan of the proposed publication should be prepared for examination by each meteorological service. A sub- committee, composed of MM. Pernter (president), 3illwiller, Neumayer, Rykatcheff, Mohn and Tacchini, NO. 1564, VOL. 60] was nominated for the purpose of considering the ex- tension and improvement of international telegraphy for weather prediction. Finally, it was decided that the International Meteorological Committee and the various sub-committees should meet in Paris in the year 1900, immediately after the Meteorological Congress which will take place on the occasion of the Exhibition. This Congress will probably be held during the first half of September. Weare indebted to M. Lancaster’s summary in Cie/ et Terre for the notice of this meeting. THE COMING SHOWER OF LEONIDS. DPSING the past few years English observers, in their efforts to witness returns of the Leonid meteors, have met with little but disappointment. Either the firmament has been overcast at the important time, or the display has been very weak. The rarity and singular attractiveness of a really fine meteoritic ex- hibition are such that the immediate prospect of viewing an event of the kind has aroused great interest in the whole subject of shooting stars. But we have been a little premature in our anticipations in recent years, and looking for the appearance of the meteors before the vanguard of the denser portion of the stream had begun to cross the earth’s path. There can, however, be no doubt as to the character of the ensuing display. The earth will be sure to encounter one of the richest regions of the orbit at the middle of November, but whether or not this collision will occur at an hour perfectly suitable for its observation remains to be seen. It must be ad- mitted that the exact time of the vezcontre cannot be definitely stated. The materials upon which computations have to be based are not sufficiently numerous and con- sistent to enable exact deductions to be drawn from them. Moreover, there is evidence to show that the system of meteors is constantly undergoing changes. The particles are spread out, and are still spreading out, over a very considerable section of the orbit, and are subject to per- turbations by the larger planets. Different sections of the stream are affected unequally, so that the whole system, both as regards its conformation and distribution, suffers from such irregular disturbances, that we must be prepared for the visible signs of developments of an un- expected character. In the present state of our know- ledge it is impossible for us to allow for all the various circumstances and conditions which control the visible aspect of the shower, from year to year, and modify its orbital elements. Calculations which have been made independently by several authorities show that the influence of Jupiter and Saturn, since the last return of the shower in 1866, has been exerted in increasing the node, so that the pheno- menon may be expected a day late in the present year It will probably occur just before sunrise on November 16. Drs. Stoney and Downing, in a paper published in the Proceedings of the Royal Society, vol. Ixiv. p. 406, state that a noteworthy outcome of their investigations is that the meteor-group which gave rise to the display in 1866, made a near approach to Saturn in 1870, and to Jupiter in 1898. On the latter occasion the meteor-cloud was distant from Jupiter by an interval of space less than that separating the earth and the sun. Berberich (Ast. Wach., 3526) has also discussed the orbit-perturbations of the Leonid stream, and concludes that the meteors will appear about a day later than they would have done under normal conditions. If there had been the average annual displacement of the node (equal 102’°6) the re- currence of the shower might have been anticipated on November 15 at about 1 a.m., but the perturbations seem to have increased the longitude of the node to the extent of 11°; so that the greatest intensity of the dis- play must be awaited on the morning of November 16, in the twilight preceding sunrise. OcrToseER 19, 1899] WAT ORE But it must be admitted that these deductions are liable to some uncertainty. Last year the predicted late- coming of the meteors was far from being corroborated by observation. The maximum number of meteors was recorded on the morning of November 15, and very few Leonids were presented on the following morning, though computation had indicated the latter as the time of maximum. In view of the prevailing doubts there seems no alternative but to watch for the shower throughout the morning of the 15th, and failing its brilliant apparition then, to repeat the watch on the morning of the 16th. The maximum may be displayed at any time between November 15, oh. 30m. a.m. and November 16, 6h. 30m. a.m. In England a November sky is cloudy on at least three nights out of four, and this year we shall have moonlight to consider as well, for our satellite will be nearly full, and must largely detract from the striking character of the display. Should the meteors ap- pear on the morning of the 15th, they might, however, be seen on a dark sky, for the moon will set about 23 hours before sunrise. The Leonids are fine meteors; a large proportion of them are as bright as Ist mag. stars, and, notwithstanding moonlight, will create a conspicuous effect if they return in great numbers. On the occasion of the last grand display on the morning of November 14, 1866, the writer was much struck with the number of tolerably bright meteors, and observed several which were many times brighter than Venus at her best. These Leonid fireballs gave lightning-like flashes, and left short green streaks, enduring for five, ten, fifteen minutes, and even more. The approaching display will be sure to supply a few of these splendid objects. fixing the time of the maximum and strength of the display. A table with writing material and a lamp should be at hand so that numbers and notes can be hurriedly recorded by the observer almost without diverting his attention from the heavens. With more than one observer the various aspects of a meteoric shower can be fully recorded, but it is impossible to suppose that one person can watch its progress and record all the details presented. Observers need not specially record the meteors with the main object of fixing the centre of radiation. We have already obtained a great number of eye-estimates of this position, and these must be put aside for the more accurate values obtainable by photography. No doubt the latter method will be extensively brought into requisition, though the bright moonlight will afford At every station where the weather enables the shower to be successfully witnessed, certain features ought to be particularly recorded. The meteors should be counted, and the time of maximum ascertained. It will be useful also to determine the hourly rate of apparition by noting at certain regular intervals the number which appear. By counting during short intervals and continuing the work for several hours, the rise and fall of the display as well as the number per minute at and near the time of maxi- mum might possibly be obtained. In the event of an exceedingly abundant display, similar to that seen in America in 1833, the observer may feel bewildered and find it impossible to record the exact numbers. In such a case the figures should be estimated as carefully as possible. Another feature will be to preserve a description of the time, brightness and apparent paths of any specially fine Leonids that may be visible. The paths should be marked on a celestial globe or suitable star-map, and the Right Ascension and Declination of their beginning and end points registered in a book properly ruled for the purpose. The length, duration and possible drifting of the luminous streak, left by every bright meteor, should also receive attention. Near the time of maximum, how- ever, these details may be disregarded, as it will be necessary for the observer to concentrate his efforts to NO. 1564, VOL. 60] @® @ e I ed! I Iie AE a serious hindrance on the present occasion. The Leonids begin to fall as early as November 7, and the shower is sustained over a fortnight. It will be very important to look for the meteors of this stream between about November 7-11, and record the paths of those visible with a view to definitely ascertaining the position of the radiant. At this early period of the shower’s activity it is not probable that the photographic method will be appealed to. It is to be hoped that all regular meteoric observers will follow the progress of the shower with close attention during the second week of Novem- ber in this year, for the questions as to the date of commencement of the shower and as to whether the radiant is a shifting or stationary one are very inter- esting features requiring settlement. W. F. DENNING. 594 NATURE [OcToBER 19, 1899 NOTES. CotoneL J. W. Orriry, C.1.E., has been appointed president of the Royal Indian Engineering College, Coopers Hill, in the place of Colonel Pennycuick, C.S.I., resigned. THE Committee of the British Association Table at the Naples Zoological Station announce that the Table is fully occupied until the middle of April next, but that applications for its occupancy from then until the end of August 1900, should be sent at once to the Hon. Secretary of the Committee, Prof. Howes, F.R.S., at the Royal College of Science, South Kensington. Mr. Kyle will occupy the table from now until Christmas, when he will be succeeded by Mr. M. D. Hill, who will continue investigations on the reproduction processes of Crustacea, and in March Prof. Herdman will go out and devote a month to the study of the Tunicata of the Bay. THE Harveian Oration was delivered at the Royal College of Physicians by Dr. J. Vivian Poore on Wednesday last. AN address will be given to the North-west London Chemical Society, on October 24, by Dr. Lauder Brunton, F.R.S., who will take as his subject ‘‘ Biliousness and Gall Stones.” On November 2, Sir J. Burdon-Sanderson will deliver an introductory address to the Middlesex Hospital Medical Society. To this all past and present students of the hospital are invited. A TELEGRAM from Amsterdam, dated October 12, states that a violent earthquake has occurred in the south side of the Island of Ceram, in the Dutch East Indies, causing the death of some thousands of persons and the complete destruc- tion of the town of Amhei. Details, however, are wanting. AT a meeting of the Finance Committee of the Lincolnshire County Committee, held on the 13th inst., it was resolved that the County Committee be recommended to give their consent to the erection, within the grounds of Lincoln Castle, of an observatory for the preservation and use of certain astronomical instruments offered to the county by the executors of the late Canon Cross, of Appleby. The recommendation was made that the committee’s consent should be given subject to the condition that the buildings shall not be commenced until sufficient funds have been raised for their erection and the future maintenance of the instruments. It is proposed to raise the funds by public subscription. We trust there will be a hearty response to the appeal that is to be issued. AT a meeting of the Council of the London Mathematical Society it was resolved that the president (Lord Kelvin), the three vice-presidents, the treasurer, and the two secretaries should be nominated for the same offices at the annual meeting on November 9 next. Of the other members, Messrs. W. H. H. Hudson, D. B. Mair, and W. D. Niven, C.B., retire from office, and Messrs. W. Burnside,H. M. Macdonald and E. T. Whittaker were nominated to fill the vacancies. The Council also em- powered the secretaries to publish an ‘‘ Index” to the first thirty volumes of the Proceedings, on the lines of the similar index to the first fifty volumes of the AZa/hematesche Annalen. Mr. Tucker was further authorised to draw up a complete list of members from the foundation of the Society in 1865. Tue Council of the Royal Photographic Society have decided to institute a series of monthly meetings, extending from November to April, to be especially devoted to illustrated lantern lectures. The meetings will be held on the first Tuesday in the month, and the first will take place on November 7. THE second Traill-Taylor Memorial Lecture will be delivered on November 14 at the rooms of the Royal Photographic NO. 1564, VOL. 60] Society by Major-General Waterhouse, who will take as his. subject ‘‘ The Teachings of the Daguerreotype.” THE third International Congress of Photography is to be held in Paris from July 23 to July 28, 1900. Its purpose will be to re-examine decisions arrived at by the two last Congresses on problems before the Society, and to see if such are capable of further improvement or perfection. To inquire into the various new photographic questions arising since the last meeting. Practical demonstrations of working methods, lectures on special subjects, and visits to scientific and industrial insti- tutions also form part of the programme. Those intending to be present are requested to address the General Secretary, M. S. Pector, 9 Rue Lincoln, Paris. : THE magnetic survey of Maryland has now been practically completed, the distribution of stations being such that on the average there is one station for every hundred square miles, The expenses of the work, with the exception of this year, have been entirely borne by the Maryland Geological Survey. A SCIENTIFIC and commercial mission, under the direction of M. Ernest Milliau, Director of the Laboratory of Technical Experiments in connection with the Ministry of Agriculture, Paris, has been sent to Russia and Roumania with the object of taking measures for facilitating and extending business relations with those countries, especially with regard to the exportation of olive oils. A BACTERIOLOGICAL institute has recently been established at Vladivostok, and a similar institute is shortly to be opened at Merv in Central Asia. OwING to the prevalence of enteric fever in Natal, every man ordered for military service in that Colony has, says the Lancet, been given the option of being inoculated with anti-typhoid serum, and 70 per cent. of the troops have accepted the offer. THE late Prof. O. C. Marsh’s executors are about to sell his valuable collection of orchids, objects of art, antiquities, &c., for the benefit of the Yale University. ACCORDING to the Sczentific American, Japan is to send out an Arctic Expedition. The Japanese Government wishes, says our contemporary, to develop in the Japanese the spirit of adventure and discovery which has rendered the English nation so powerful. THE New York Zoological Park, situated in Bronx Park, is to be opened to the public this month. The Scéentzfic American states that the specimens which will be ready for public inspec- tion will form but a small part of the exhibit, and that these will be very interesting. THE return, after an absence of two years, of Mr. A. J. Stone, of New York, is announced. Mr. Stone has been travelling in the Arctic regions during the time mentioned, studying the geo- graphical distribution of animals. It is reported that during five months of travel last winter he covered 3000 miles of coast and mountain entirely above the Arctic circle. Science announces the return from Manila of the Johns Hopkins University Commission, which, under the direction of Dr. S. Flexner, has spent the past summer in studying tropical diseases. THE death is announced, from Vienna, of Dr. Oscar Baumann, who had acquired some reputation as an African explorer. In 1885 Dr. Baumann joined the Austrian Congo expedition, sub- sequently visiting the island of Fernando Po, the Cameroons, and parts of East Africa. Other expeditions followed, in one of which he fell into the hands of hostile Arabs, and was only released on the payment of a ransom, . He was entrusted with OcrTosER 19, 1899] NATURE S85 the command of an expedition fitted out in 1889 by a German anti-slavery association. In the following year he explored the Usambara, and made preliminary observations for the purpose of tracing a projected railway in that region. In addition to a map of the Congo and numerous contributions to the reports of the Geographical Society of Vienna, Dr. Baumann published three books dealing with his travels and observations in Fernando Po and Usambara and with the rising in German East Africa. WE regret to notice the death of Dr. J. W. Hicks, the Bishop of Bloemfontein, which has just taken place. The late Bishop was an earnest student of science, and was at one time a demonstrator in chemistry in the University of Cambridge, and published a text-book on inorganic chemistry. He was also a fully qualified medical man, having been made an M.D. in 1864, and an M.R.C.P. in 1865. THE death has occurred, at Adirondacks, New York, of Mr. Hamilton Y. Castner, well known for his work in connection with the manufacture of aluminium and the establishment on a manufacturing scale of a process for the electrolytic production of alkali and bleaching powder from common salt. THE National Geographic Magazine states that various sites within a radius of twenty-five miles of Washington are being examined by parties under Dr. Bauer’s direction for the deter- mination of the best location for the Coast and Geodetic Survey Observatory. The examinations thus far made have disclosed some interesting regional disturbances, especially in the vicinity of Gaithersburg. In order to determine what influence such regional disturbances have upon the variations of the earth’s magnetism, such as, for example, the diurnal variation or the secular variation, it is proposed to mounta sensitive Eschen- hagen dedinetograph at Gaithersburg, with the aid of which the variations of the most sensitive of the magnetic elements—the declination—will be continuously and automatically recorded. Tue British Fire Prevention Committee made a series of fire tests yesterday at their testing station as we went to press. The tests on this occasion were with a concrete floor, an iron safe, and two doors of wood. We are glad to see that the committee are continuing their valuable work in so energetic a manner. Valuable results may be expected to accrue from the experiments made by the committee from time to time. A MONUMENT erected to the memory of Johannes Miller was unveiled at Coblentz on October 7. Prof. Virchow, who was the principal speaker at the cer emony, said in the course of his remarks that Miiller was a biologist, a naturalist whose aim was the study of life itself in its universality. He was the first to use the microscope in researches on living beings, the first to disclose the fauna of the seas. His example inspired the deep-sea researches of to-day. Miiller’s method was observation ; he put things into the right positions for exhibiting their action, and then registered his observations. At the time of Miiller’s youth it was believed that from inanimate nature, from atoms, from matter, or substance, new combinations might form themselves, which finally might lead to the generation of living organic forms, that, in short, plants and men might be evolved from dust. In modern times this had been spontaneous generation. Johannes Miiller warned against such hypothetic conclusions. He said : ‘* We cannot generate living substance, and as long as we cannot do so, as long as we have no proof, we must put these theories aside” ; and (said Prof. Virchow) that is the standpoint of resignation, of submission, that is the true position for a naturalist, such as Miiller was. On the occasion of the waveiling of the monument, Miiller’s daughter presented to the State Library fourteen volumes of drawings, containing upwards of nine hundred zoological NO. 1564, VOL. 60] named sketches made by her father in the years 1850-1854 in various countries. Tue Indian correspondent of the Zancef states that new regulations have been made with reference to persons sending or taking from place to place in India cultures or other articles known or believed to contain the living germs of plague. No person who is not a commissioned medical officer, a military assistant surgeon, or a medical practitioner in possession of a qualification not lower than that of L.M.S. of the University of Calcutta, Madras or Bombay shall without the special per- mission of the Governor-General in Council or a local govern- ment take in his private possession from one place to another any cultures or other articles which he knows or believes to contain the living germ of plague. No such culture shall be sent from one place to another unless it is securely packed in a hermetically closed tin of adequate strength, placed in a strong outer box of wood or tin, with a layer of at least three-quarters of an inch of raw cotton wool between the inner and outer case, the outer case being enclosed in a stout cloth, securely fastened and sealed, and labelled with such distinguishing inscription as will suffice to make immediately manifest the nature of the contents. ACCORDING to a recently issued consular report, a new process for the production of ammonia has recently been dis- covered in Germany. The process is said to be at present an expensive one, but this difficulty will, it is thought, be over- come. An American paper, the Pharmaceutical Eva, has published an article by Mr. H. M. Whelpley, of St. Louis, in which particulars are given as to the use of the metric system in American physicians’ prescriptions. It appears from the article that out of 1,008,500 prescriptions examined, only 6 per cent. were in the metric system. The information was obtained from apothecaries in forty-two States and territories. A sHoRT article in the current number of the Wational Geographic Magazine sums up in brief the main results of Lieut. Peary’s explorations in 1898-99, from which we extract the following information :—In the south Peary discovered that the so-called Hayes Sound, north-west of Cape Sabine, is only an inlet or bay. It was supposed by many that it extended through to the Arctic Ocean west of Ellesmere Land, and separated that country from Grinnell Land on the north. It now proved that these regions are one and the same land. He also travelled west across the northern part of Ellesmere Land, which has never before been penetrated for any distance, and visited its west coast, joining his survey of the shoreline with the short bit of the coast further north, which Lockwood, of the Greely Expedition, discovered in May 1883. This is the first time that any part of this coast has been seen south of the inlet visited by Lockwood. In his various sledge journeys up the channel from the /Vndward’s position, Peary skirted the east coasts of Grinnell Land and Grant Land for a distance of about 250 miles, rectifying the mapping of this shore-line in some respects, and particularly the surveys of a number of indent- ations. The most northern point reached by Peary was Cape Beechey, about 82° N. latitude. No effort to push northward has been made this summer, and Peary’s winter camp has been established on the Greenland side of Smith Sound, several miles further south than his quarters of a year ago. Pror. Kocu has published his first report on his study ox malaria in Italy in the Deutsche Medécinische Wochenschrift. In all the cases of malaria examined by Prof. Koch and his assistants the parasite of malaria was found in the blood. Apart from the blood of human beings, the parasites occurred only in some species of mosquitoes which were met with only in the summer. The mosquitoes convey the malaria germs 596 NATURE [OcToBER 19, 1899 from one human being to another; the infection is especially maintained and propagated by the relapsing cases which continue all the year round and form the link between one fever season and the next, so that the mosquitoes in the begin- ning of summer always find germs. If no relapse occurred in any of the cases of malaria in any given district the mosquitoes would find no germs in the beginning of summer, and malaria would become extinct there. Prof. Koch succeeded in recog- nising certain species of mosquitoes in the dwellings of the population ; this was the more important, as the mosquitoes of this district did not usually bite during the day but only during the night. The inhabitants therefore became infected at night within their dwellings. In seven cases parasites of malaria were discovered in insects, especially in dropheles maculipennis. In many dwellings, however, where patients had contracted malaria, anopheles was not present, but another insect, Czex pipiens, was hardly ever absent. Prof. Koch ascertained that the so-called estivo-autumnal fevers were identical with tropical malaria. Industries and Tron gives particulars of an electric fog-alarm which, it is reported, has been invented by a Canadian electrical engineer. The description is as follows:—A naphtha engine supplies the motive power to a dynamo that furnishes the electric current, by means of which three pairs of electromagnets operate half a dozen clappers that strike against a large gong with a frequency of about 36,000 strokes a minute, producing an almost continuous sound. Its effectiveness is enhanced by a mechanism somewhat on the principle of a megaphone, by means of which the sound is not only intensified but thrown in the required direction. A model of this fog-alarm was not long ago tested at Ottawa, and although it was comparatively a small affair, its sound was easily heard a distance of two miles. The sound of the completed machine will be (it is thought) dis- tinguishable at a distance of fifteen miles. As an example of the interest that is taken in anthropology on the continent, we call attention to the publication of the free courses of lectures delivered by Prof. E. Morselli at Turin and Genoa. The title of the publication is ‘‘ Antropologia Generale : Lezioni su Uomo secondo la Teoria dell’ Evoluzione.” When will it be possible for the English public to hear systematic lectures on anthropology of any kind, free or otherwise? Prof. Morselli puts his subject clearly, judging from the portions only of the two lectures that we have received. ANTHROPOLOGISTS who more particularly study European ethnology should be very grateful to Dr. William Z. Ripley, of Boston, for the ‘‘ Selected Bibliography of the Anthropology and Ethnology of Europe” that has just been issued by the Trustees of the Public Library of Boston, Mass. The list con- tains nearly two thousand titles in nearly all the languages of Europe ; the Slavic writers are very well represented. The authors are arranged in alphabetical order, and their several publications are cited chronologically ; this is followed by a subject-index. The labour of compiling this bibliography must have been immense, but Dr. ‘Ripley will have the satisfaction of feeling that he has supplied his colleagues with a valuable and indispensable tool. AMONG the most useful instruments employed in Italy for the registration of earthquake movements are the microseismo- graphs, designed by Prof. Vicentini and modified by Dr. Pacher, which have been erected in the Physical Institute of the University of Padua. Hitherto the records have been pub- lished at irregular intervals in the A¢¢z of the R. Istituto Veneto di Scienze, &c., but it is now arranged that they shall appear systematically and ultimately form an appendix to the yearly volume. The first number, recently issued, contains the register from January 1 to March 12 of the present year, and NO. 1564, VOL. 60] also notes with regard to the arrangement of the different . . instruments, THE tin trade of prehistoric Europe is a subject of consider- able interest and importance. Very recently Salomon Reinach (7 Anthropologie, x., 1899, p. 397) has again attacked the problem and has arrived at the following conclusions. A thousand years B.C. there was an almost exclusively overland trade between the British Islands and Thrace and Macedonia. The relations between Britain, Northern Europe and Western Asia have been proved by archzology, by the diffusion of tin, amber, spiral ornaments and the types of bronze arms and utensils. Thus it is not surprising that Homeric Greece about 800 B.c. knew not only the Celtic name of the Cassiterides, but the phenomenon of the short nights of the north of Britain. The overland tin was brought to the gean, if not by Greeks, then by Barbarians. These Barbarians, accurately knowing the country from which the tin came, sought a marine route in order to retain this precious trade in their own hands. This was rendered more feasible by the invention of the anchor by the legendary Midas of Phrygia, for then ships could ride with safety in the open. Reinach considers that it was he who first brought tin and lead to Greece by sea by the north-west route, and it was only later that the Pheenicians got the tin trade into their hands, The English Leake, Hamilton and Ramsay have rediscovered Phrygia, but twenty-seven centuries ago the Phrygians discovered England. THE Bulletin de la Société Astronomigue de France for October contains several interesting meteorological articles. M. E. Touchet contributes an illustrated articleon the storms of August and September 1899, showing some excellent light- ning pictures. He gives special attention to the type of lightning which is apparently unaccompanied by thunder. M. A. Souleyre, writing on the ‘‘distribution of rain on the earth,” summarises the interaction of the various air-currents and the barometric variations connected with rainfall. MM. V. Farquon and F. A. Mavrogordato give short accounts of their observ- ations of the ‘‘green ray” on the Alps and at Smyrna respectively. THE October number of the /Jows7al of Conchology contains an interesting paper by Messrs. Melvill and Standen on the cowries of the capzt-serpentes group. In that group are included not only species with a dark peripheral area and a spotted centre, like the typical Cypraea caput-serpentis, C. mauritiana, and C. arabica, but likewise the ring cowry (C. avzulus) and the familiar money cowry (C. monefa). The two latter, as many of our readers are aware, are white; the yellow ring from which the second of the two derives its name marking the line ~ of division between the spotted central and the dark peripheral area of the serpent-head cowry (C. caput-serpentis). If proof were necessary to demonstrate that this is the true explanation of the coloration of the two species, it is afforded by the dis- covery of a white example of a variety of capzt-serpentis, in which the dorsal spots are still faintly visible. It has been recently stated by another writer that ‘‘from the ring cowry may easily be derived the money cowry, in which the ring has all but disappeared, while the marginal area has developed a series of rugosities, apparently connected with the filaments on the margins of the mantle lobes.” And Messrs. Melville and Standen now come to the conclusion that these two cowries are really nothing more than races of a single species, for which the name C. woveta should be retained. Tue last number of the 7yvazsactzons of the Norfolk and Norwich Naturalists’ Society bears ample testimony to the maintenance of the taste for natural history and botany which has always been so characteristic of that favoured county. As is only proper, the great bulk of the papers refer to local OcToBER 19, 1899 | subjects, while a few, like Mr. Warde Fowler’s notes on the birds of the Somme Valley, supplement the history of native species in other lands, the remainder having no particular con- nection with the county. Especial interest attaches to Mr. S. F. Harmer’s note on the occurrence of the well-shrimp (Vzphargus) near Norwich ; and likewise to Mr. J. H. Gurney’s account of the distribution of the Bearded Tit. Various specialists bring the lists of the Norfolk fauna and flora up to date. And those who study economic zoology will be interested in the notes of Mr. G. H. Harris on the herring fishery of 1898. So far as the Yarmouth boats were concerned, this appears to have been a practical failure. It was not that the catch was always bad ; but, whatever the catch, prices were forced down by the poor quality of the fish. And this is mainly attributed to the mild season, herrings being never of high quality in warm weather. AMONG recent papers in the Journal oy Applied Microscopy, Mr. Charles J. Chamberlain's series of articles on ‘‘ Methods in Plant Histology” will be useful to teachers and students of practical botany. The last articles contain illustrated accounts of the principal families of algze with methods of preparing for observation. One of these methods is, however, capable of improvement. To place specimens ina Io per cent. solution of glycerine, and allow the solution to evaporate till it is of the consistency of pure glycerine would be unnecessarily tedious. It is simpler and equally efficacious to place the specimens in water in a small receptacle of parchment paper, and float the latteron glycerine, the change of density taking place through the paper by osmosis instead of by evaporation. A very clear photographic group of official members of the recent Dover meeting of the British Association, together with members of the French Association and the Belgian Geological Society, has been sent to us by the photographers, Messrs. Lambert Weston and Sons, of Dover, from whom copies may be obtained. In the majority of instances the individuals portrayed can easily be identified. THE additions to the Zoological Society’s Gardens during the past week include a Rhesus Monkey (A/acaces rhesus, 9 ) from India, presented by Mrs. J. Adams; fa Black-faced Spider Monkey (Aéeles ater) from Eastern Peru, presented by Mr. Claude P. Landi; a Common Chameleon (Chamaeleon vulgarts) from North Africa, presented by Mr. A. H. Ryan; a Red- cheeked Souslik (Spermophilus erythrogenys), four Eversmann’s Sousliks (Spermophelus altaicus), four Altai Sousliks (Sper- ophilus mugosaricus) from Western Siberia, a Common Seal (Phoca vitulina), British, a Common Cormorant (Phalacrocorax carbo, var.), European, an Emu (Dromaeus novae-hollandiae), three Long-necked Chelodines (Chelodina longicollis) from Australia, an Uveean Parrakeet (Vymphicus wvaeenszs) from the Island of Uvea, a Rosy Parrakeet (Palaeornis rosa) from Burmah, a Four-lined Tree-frog (Polypedates quadrilineatus) from the East Indies, a Westerman’s Eclectus (Zc/ectus wester- manz) from Moluccas, deposited; six Glossy Ibises (P/egadi's falcinellus), bred in the Gardens. OUR ASTRONOMICAL COLUMN, CoMET GIACOBINI (1899 2). Ephemeris for 12h. Berlin Mean Time. 1899. R.A. Decl. Br. : bh. m. s. at Oct. 19 16 57 8 +0 464 21 Peet 7: 0) 3 I 190 BO471 23 a5 2 59 TG ee 25 og 555 2 23°0 . 0°66 27k. 8 52 nee 2 54°5 29 ely) 11 49, Boo ar gh en . 0°62 NO. 1564, VOL. 60] NATURE Sy A circular from the Centralstelle at Kiel informs us that owing to an error in one of the published observations, there is some doubt as to the correct elements of this comet. In consequence of this the above ephemeris may not be quite accurate, but, as according to the latest observation recorded, it is less than one minute in R.A. and two minutes in Decl. in error, it will be useful for searching purposes. The comet is travelling to the north-east through Ophiuchus, a little south of the second mag. star a Ophiuchi. HotMeEs’ CoMEr (1899 @). Ephemeris for 12h. Greenwich Mean Time. R.A. 1899. = A Decl. es: °. ‘ “a Oct. 19 Deo ouer +48 49 51 20... 51 57 48 54 5 Pat ee) GOGH Bbc 48 57 56 22 A OWAA I eece Aoetee2s PR a deer GEAABION oko 49 4 30 Bt em LOPE EQ) fp 2S 2B coo CHD) LY 49 9 33 20m eras) 07, +49 II 29 This comet is now in the middle of Perseus, being nearly on the line joining 8 and y Persei, about two-thirds of their distance from the former. OPPOSITION OF JUPITER, 1899.—Astronomische Nachrichten (Bd. 150, No. 3596) contains the results of several observers” work on the planet during the last opposition of 1899 April 25. M. J. Comas Sola, of the Catala Observatory, gives a plani- spheric map of the markings observed by him with a Mailhat objective of 22 cm. aperture, from February 18 to July 8. Tables are given showing the various rotation periods obtained from observations of spots in different zones, a summary of which is as follows :— Mean velocity of spots on ea =gh. 50m. 2335s. border of equatorial zone (from 22 spots) Mean velocity of spots on north | =9h. 50m. 15725s. border of equatorial zone... J_—_ (from 9 spots) *, mean equatorial velocity =gh. 50m. 20°76s. This, compared with Denning’s mean velocity for 189%, gh. 50m. 23°6s., would indicate an acceleration since the spring of 1897. Measures of the “‘ red spot ” gave a period of gh. 55m. 41°S5s. Herr Ph. Fauth also gives a planispheric drawing showing the details observed from May 30 to June 13, with a Pauly objective of 17°8 cm. aperture. Mr. A. Stanley Williams, of Brighton, gives his observations of the ‘‘red spot” made during the period March 13 to June 16 with a 64-inch reflector. The period found is given as gh. 55m. 42°65s. from 229 rotations (March 13 to June 16). He finds the spot to be a little shorter now than it was in 1887 (31°°7 instead of 34°7). Law ConNnEcTING Morions IN PLANETARY SYSTEM.— M. Ch. V. Zenger, of Prague, has recently put forward the results of work he has been engaged on for some years past, and a part dealing with the relations existing between the “time of a planet’s revolution” and its position in the solar system appears in the Bulletin de la Soc. Ast. de France, October 1899, pp. 431-434. He finds that the orbital movements of the planets and also of some periodical comets have a simple law connecting them with the time of the sun’s rotation. If “7 cs is the time of votatéon of the central controlling body, then “RR,” the time of orbital revolution of the planet, is given by the relation R=22-; where ‘‘7” is a whole integer, different 2 for each body. Taking Faye’s value for the solar rotation = 25:2 days, =12°6 days, and the author gives the following data :— Mercury Venus Earth Eros Mars Jupiter Saturn Uranus Neptune N= 7 I 29 5I_ 54 344 854-243 4776 R=88:2d. 226°8d. 365°4 642°6 680°4 4344°4 10765°4 30603°6 601776. Between the earth and Eros, the author mentions the possible existence of a hitherto unknown planet for which 2=40, and the period of revolution of which would therefore be about 500°4 days. ; Several tables are also given showing the conformation of the satellites of the various planets to a similar relation, and the author considers the whole as helping to confirm his electrical theory of the solar system. 7 2 I 598 NATURE [OcToBER 19, 1899 ON THE CHARACTERISTICS OF A UNIVERSITY. “THE beginning of a new academical year is one of those periods of sudden change which must leave its mark for good or bad on every university and college in the land. Well-known faces of those who have been prominent in work or sport are missing. New recruits are taking, with halting steps, their first lessons in the drill which is soon to become so familiar. In a few days they will be undergoing their ‘‘ baptism of fire” in struggles wider and keener than any in which they have yet been engaged; and in which each, according as he bears himself, must either add to or diminish, be it by ever so little, the position which his college holds in the eyes of the world. At such a period we naturally halt for a moment, and ‘before we face the future, cast our eyes backward. One conspicuous change has taken place in the past session. Sir John Donnelly has retired from the permanent headship of the Department of Science and Art, and has been replaced under new conditions by Captain Abney. It would be contrary to all the wholesome traditions which govern the conduct of servants of the Crown if I attempted to discuss these important events. TI will therefore only say, in words which are colder than my feelings, that we wish our late chief long life, health and happiness in the rest to which the strenuous service of many years has entitled him ; and that we welcome as his successor one who is not only a distinguished public servant, but a dis- tinguished man of science. Two losses, I must mehtion, of men who, though unknown to each other, were both known to many of us. Both had, in dif- ferent ways, deserved well of the college. Both have passed away since the last term ended. But though alike in these respects, their fates were strangely different. Sir Edward Frankland, for long Professor of Chemistry in this college, had touched the topmost rungs of the ladder of scientific fame. The Royal Society bestowed upon him its highest honour—the Copley Medal. The French Academy of Sciences had given him the highest distinction it can confer upon one who is not a Frenchman, by placing his name on the select list of eight foreign members. Happy in the work of his life, he was no less happy in the opportunity of death. Theend came, without long previous suffering or slackening of mental power, in the midst of the holiday haunts which must, as life faded, have recalled some of its brightest hours. The Royal College of Science will remember him as one of the earliest and the most distinguished members of its staff. The other name I would mention is that of one who was re- cently numbered among our students. Ernest Harrison gained the Associateship in Physics a year ago, taking the first place in the final examination. He had previously won a scholarship at Trinity College, Cambridge. His career here gave reason to believe that his future would be successful ; but his early death has quenched the hopes of his teachers and his friends. The fact that he has died a very young and therefore a comparatively unknown man, makes it all the more the sad duty of us who knew him to record the promise of his youth. Turning from the past, the changes which loom largest in the immediate future are the erection of the new buildings and the creation of what will in effect be a new university. Of the former I will only say that they will be on a scale not unworthy of the largest city in the world; but the establishment of a teaching university must be so pregnant with good or ill that I shall offer no apology for returning, by a somewhat different line of approach, to a subject on which Sir Norman Lockyer dwelt last year. Let us then, in the first place, ask what are the chie, notes which distinguish from all others the mode of preparation for the work of life which should be characteristic of a university. Put shortly, I take it that two notes are predominant above all the rest. The first is that a university is a place where education is combined with the advancement of knowledge ; the second, that the teaching of a university is based upon the principle that knowledge is desirable for the influence which knowledge and the search for knowledge exert upon ourselves, and not merely for the power which they confer of improving our external surroundings. The first of these characteristics dis- *s the university from a school; the second from a 1op or a college with purely technical aims. \ddress delivered at the opening of the Royal College of Science, Ox. er 5, by Prof. Riicker, F.R.S. NO. 1564, VOL. 60] I shall say very little on the fact, which no one will dispute, that it is the duty of a university to advance knowledge. To do us justice, we of the Royal College of Science have not been unmindful of this duty. It is impossible to speak of the present or more recent past, but I may be permitted to say that a college which has numbered Huxley, Stokes and Frankland among the members of its staff will have forgotten all the teaching of its earlier history if it ever fails to satisfy the first test of fitness for a university status. I only hope that the schemes which are being mooted for founding new research pro- fessorships do not veil an attempt to place in other hands that part of the work of the London colleges which is specially characteristic of a university. London needs a multiplication of teachers on a sufficiently large scale to enable them to conduct both teaching and research, not the creation of separate castes of teachers and investigators. ’ Let me turn next to the second note of a university, viz. that it insists that knowledge has a value apart from the com- mercial or utilitarian objects for which it may be used. In this capacity a university maintains, or ought to maintain, a constant protest against the view that a man and _his knowledge are to be measured by their money value alone. This view was never more clearly expressed than by Colonel Diver, according to whom the aristocracy of New York con- sisted ‘‘ of intelligence, sir, . . . of intelligence and virtue. And of their necessary consequence in this republic—dollars, sir.” It is needless to deny that ‘‘dollars” are often the reward ox intelligence and virtue. In the case of most men, the search after them must necessarily be a matter of importance ; but this fact is too often used to make preparation for the business side of life the only or the chief end of education. As I was writing these lines a number’ of Lzterature reached me, in which there is a review of a work by an assistant pro- fessor of the history and art of teaching in the Harvard University. This gentleman proposes to have ‘‘ commercial courses” in all the schools. The purpose of these courses is to be, not merely ‘‘to train a youth,to an appreciation of the functions of business and business practice in our modern life,” and not merely to ‘‘ inform him as to the history of industry and trade,” but also to ‘awaken in him a profound interest in busi- ness as such,” and to ‘‘train him to keep his eyes open to business possibilities.” Before I have done you will understand my reasons for agree- ing with the reviewer that this is a ‘‘ hideous educational pro- gramme.” For the moment I will content myself with saying that it is based upon a one-sided view of life. There can be no question but that the business element is important, but a uni- versity is a corrective to the tendency to regard money as the only standard of value. This it does by inviting us to study and to care for things which we must admit are important and beautiful, but which we may not be able to convert into coin. But, you may ask, if this is so, will not the admission a technical colleges such as is, in part, our own, be inconsistent with your idea of a university ? To this I answer that, while it is possible that the desire to master the practical applications of knowledge might crush the desire to know things which are worthy to be known though not of immediate commercial advantage, the men who are managing the best technical colleges are aiming at leavening the technicalities of a profession with the love of knowledge. Example will illustrate what I mean better than precept. The late Dr. Hopkinson was a successful engineer, sought after to superintend great undertakings. Busy in the office and the law courts, he nevertheless was always investigating the secrets of nature, and wrote his name large in the Zyavsactions of the Royal Society. Many others, whom in this room I need not mention, are animated by the same spirit. I think, therefore, that the welcome which several of our universities have extended and are extending to such men and to their students is a legitimate recognition of the fact that they have effected a real extension of the boundaries of the region in which the love of knowledge for its own sake prevails. It would be a disaster if the spirit of business and commerce were to dominate a university. It will be a triumph if the love of science and the love of culture were spread from the technical college to the machine shop and the factory. And this brings me to my next point, to another and more subtle question, in some respects similar to that we have been discussing. In life there is a competition, not merely between commercial — OcrToBER 19, 1899] NATURE 599 and intellectual interests, but between different intellectual interests themselves ; and a characteristic of a university educa- tion is that by some means or other it aims at conveying, not merely accurate knowledge on some one subject, but a healthy interest in all forms of mental effort. This wider range, this general cultivation, should distinguish the university scholar from him who has merely mastered the technicalities of a profession. A man may be a good lawyer or tradesman, he may have grasped a branch of pure science or succeeded in a scientific profession, and yet be careless and ignorant of all that does not bear upon the central interest of his life. The blend- ing of expert and general knowledge, of professional skill in some one subject and of intelligent interest in others, is not to be accomplished by obeying formal rules, such as those which must be followed in producing a given chemical compound. Each one of us must decide for himself what particular com- bination represents for him the maximum of gain and the minimum of loss ; but the true university as distinguished from the professional or technical school is for ever preaching that man is many-sided, that the light of heaven reaches him through many windows, and though to some of us the call may come to sacrifice all else to gain one supreme end, yet it is well to count the cost and to remember that the loss may outweigh the gain. In speaking of sacrifice I am not now referring to the ordinary habits of industry and self-control which are essential to success in any physical or intellectual struggle. Iam dealing rather with that sacrifice which is so often made without any sense of loss, the surrender of all effort to understand the appeal made by nature or art to one or other of our higher intellectual powers. A man may be so interested in painting or in music that he loses all sense of the divine curiosity which impels the man of science as he strives to unravel the plan of the universe. The seeker after truth may allow the dry light of science to wither the sensibilities which can be touched by art alone. He may purchase the higher knowledge at the cost of the higher emotions. Let us then consider for a few moments the principles which should direct our choice, and the help which a University of London can give us in choosing. With regard to principles, it is impossible, as I have already said, to lay down any hard and fast rules. In this, as in so many other questions on which a practical decision must be made, two extreme courses are possible to follow, either of which is in most cases clearly wrong. I shall call before you a distinguished advocate of each, and allow them to plead in their own words. The first policy may be called the policy of concentration, dear to the apostles of the gospel of self-help. ““The one prudence in life,” says Emerson in his essay on Power, ‘‘the one prudence in life is concentration ; the one evil is dissipation: and it makes no difference whether our dissipations are coarse or fine ; property and its cares, friends, and a social habit, or politics, or music, or feasting. Every- thing is good which takes away one plaything and delusion more, and drives us home to add one stroke of faithful work. Friends, books, pictures, lower duties, talents, flatteries, hopes— all are distractionsjwhich cause oscillations in our giddy balloon, and make a good poise and a straight course impossible. You must elect your work ; you shall take what your brain can, and drop all the rest.’ Only so can that amount of vital force accumulate which can make the step from knowing to doing. . . “Tisa step out of a chalk circle of imbecility into fruitfulness. ” And yet what counsel is this! To you the happiness or sorrows of your friends are to be mere distractions which make a straight course towards the conclusion of your own task im- possible. Politics—that is the well-being of your country ; books, the whole world of literature ; music and pictures, all these are mere playthings and delusions, which you are to cast aside with all other childish things, and now that you are a man you are to care only for doing your own stroke of faithful work, ; It is nothing to you that you are viewing with callous in- difference the faithful work of others. ‘ At sundry times and in divers manners” the noblest of our race have been striving to express the best that was in them by poetry and prose, by line and colour, by oratory and music. You are to care for none of these things. They are dissipations—not indeed of the coarsest kind—but dissipations none the less, dissipations which dis- tract you from your own sustained and self-conscious endeavour NO. 1564, VOL. 60] to do something which may perhaps entitle you to rank among the meanest of those whose works you spurn. And then, when: the work is done, the discovery made, the memoir published, what wonder if they in turn regard it with a disdain not less than your own? what wonder if Charles Lamb, along with Court Calendars, Directories, Draught Boards, bound and lettered on the back, and Almanacs, should place scientific treatises in his list of Biblia A-Biblia ; or Books which are not Books ? Turn now to the other extreme policy, that which regards it as our wisdom to aim, not so much at one high end which can be attained only by an intense concentration, as at the ‘‘fruit of a quickened, multiplied consciousness.” No one has put the case in support of this philosophy more: eloquently than Walter Pater in the celebrated conclusion to his ‘* Studies in the History of the Renaissance.” The passage is too long to quote in full, but he tells us that the service of culture to the human spirit ‘‘is to startle it into a sharp and eager observation. “Every moment some form grows perfect in hand or face $ some tone on the hills or sea is choicer than the rest ; some mood of passion or insight or intellectual! excitement is irresist- ibly real or attractive for us—for that moment only. ‘Not the fruit of experience, but experience itself is the end. A counted number of pulses only is given to us of a variegated, dramatic life. How may we see in them all that is to be seen: by the finest senses? How can we pass most swiftly from point to point, and be present always at the focus where the greatest number of vital forces unite in their purest energy ? ** To burn always with this hard gem-like flame, to maintain this ecstasy, is success in life. Failure is to form habits; for habit is relative to a stereotyped world ; meantime it is only the roughness of the eye that makes. any two persons, things, situations, seem alike. ‘*While all melts under our feet, we may well catch at any exquisite passion, or any contribution to knowledge, that seems by a lifted horizon to set the spirit free for a moment, or any stirring of the senses, strange dyes, strange flowers, and curious odours, or work of the artist’s hands, or the face of one’s friend. ‘*Not to discriminate every moment some passionate attitude in those about us, and in the brilliance of their gifts some tragic dividing of forces on their ways, is, on this short day of frost and sun, to sleep before evening.” Beautiful words! Butas their music fades from the ear, as the brilliance of the ‘‘ hard, gem-like flame” is quenched by the light of day, can we accept their teaching? Not to do but to feel, not to achieve but to enjoy, is the rule of life to be de- duced logically from these premisses. If some great work is to be attempted, it is for the sake of the experience, for the joy of the effort and the success, and not for the sake of the work itself, Even ‘‘ the enthusiasm of humanity” is classed by Pater among the ‘‘high passions,” which are valuable chiefly for ‘‘the quickened sense of life” they impart ; and beyond and above them all is placed art, not because it leads to a noble end, but because it professes ‘‘to give nothing but the highest quality to your moments as they pass, and simply for those moments’ sake,” If the doctrine of concentration leads to ignorance of the work of others, the doctrine of the multiplication of states of consciousness leads to the neglect of what you yourself may do. Nay, more ; it leads to the paradoxical result that you laud and magnify the achievements of those whom, nevertheless, you count as having failed in life, if their work, like most of the best work of the world, has been brought to the birth with bitter travail; and if, in the effort to achieve, they have sacrificed the joys to be found in ‘strange dyes, strange flowers, and curious. odours.” If you have to choose one philosophy or the other, to adopt one rigid rule of life, I take it that the nobler among you would follow Emerson rather than Pater, would prefer to do ‘* one stroke of faithful work” rather than to maintain a life long ecstasy. But this is not one of the cases in which no com- promise is possible, in which we must vote “‘ Yea” or *‘ Nay,” and must put aside wholly one teaching or the other. It may be a great thing to make the efforts and sacrifices which are required in adopting an extreme position, but it is a still higher achievement to maintain through life the intellectual balance necessary for the policy of the ‘* golden mean.” I am not concerned to deny that radically different views 600 NATURE [OcToBER 19, 1899 underlay the teaching of Emerson and Pater, but nothing is more certain than that neither Emerson nor Pater meant the passages I have read to be taken in the literal sense which might be ascribed to them. Even in the teaching of science it is some- times necessary for the teacher to aim at being clear rather than correct ; to force home the appreciation of the nature of some central truth by stating it as boldly as possible, and by sacrificing the pedantic exactitude which would insist that in its very first presentment it must be hedged about with every qualification and safeguard which long experience could suggest. This was not the policy of the American teacher. Having set the mind in motion he left to its natural ‘‘ after working” the discovery of qualifications and safeguards. ““Emerson,” says Mr. John Morley, ‘‘ has not worked out his answers to these eternal enigmas, for ever reproducing themselves in all ages, in such a form as to defy the logician’s challenge. He never shrinks from inconsistent propositions, He was unsystematic on principle. ‘He thought that truth has so many facets that the best we can do is to notice each in turn, without troubling ourselves whether they agree.’”’ No better evidence of the truth of this remark could be adduced than Emerson’s treatment of the relative importance of special knowledge and general culture. We have heard him on the one side. Let us listen to what he has to say on the other. “He only is a well-made man who has a good determination. -\nd the end of culture is not to destroy this. God forbid ! but to train away all impediment and mixture, and leave nothing but pure power. Our student must have a style and determina- tion, and bea master in his own specialty. But, having this, he must put it behind him. He must have a catholicity, a power to see with a free and disengaged look every object.” Nor by putting ‘behind him” did Emerson mean that the student was to devote all his earlier years to one form of intellectual effort : and that when this had brought him compe- tence or fame, he might turn for relaxation to what he had hitherto neglected—to art or science or literature, as the case might be. “Culture,” he says elsewhere, ‘‘ cannot begin too early. In talking with scholars I observe that they lost on ruder com- panions those years of boyhood which alone could give imagina- tive literature a religious and infinite quality in their esteem.” Me who has pored too closely and too long over one study cannot in a moment cast aside the fetters which the years have woven round him, and rise up, like Samson, a terror to the Philistines. The intellectual sectarian cannot by a sudden act of will or process of conversion become the intellectual catholic. As well might he hope that the muscles which have been disused for years should suddenly rival the sturdy frame of the athlete, that the bent back should become straight, and the vision of the wearied eyes keen. Mental, like physical powers, are atrophied by disuse. The arts of seeing something of many things and all of one must be cultivated at the same time, or side by side. And Pater, like Emerson, trusted to the intelligence of the reader not to mistake the strong presentment of one side of a question for a judicial decision on the whole case. So shocked was he when it was pointed out to him that his teaching might be taken too literally, that he actually suppressed the magnificent passages I have read to you lest his meaning should be misunder- stood. For each of us, then, the safest path lies somewhere between these limits, though thousands lead dull or unsuccessful lives because they shape their course perilously near to one or other of them. My object to-day is to warn you against the two ex- tremes, not to attempt to lay down rules which shall point out the best course between them, rules which could not serve for all characters and dispositions alike. Do not forget that nothing considerable is achieved without concentration. Remember that he who holds himself free to cast aside every interest which does not directly bear on the central object of his life purchases this freedom ‘‘ witha great price. ” Let us next inquire what a university can do to guide the student in his choice. And here I may say at once that in my opinion the methods which have been ofhcially adopted have been open to grave criticism ; and that even if this were not so, the secondary are at least as important as the primary effects of a university training. The direct official method of promoting general knowledge has been to insist that the candidate must pass an examination NO. 1564, VOL. 60] in several diverse suljjects either before or during his passage through the university. No objection can be raised to regulations which insist that a student before entering the university shall have acquired the ele- mentary knowledge and have undergone the intellectual training which may enable him to undertake more difficult studies ; but cultivation is not attained by mastering Latin and Greek up to the point at which they become useful engines for cultivation, and then throwing them aside for life. To change the metaphor, studies so treated are, in the words of Mr. John Morley, ‘superfluous roots in the mind, which are only planted that they may be presently cast out again with infinite distraction and waste.” Mistakes such as these are due to the fact that, though each subject of study when regarded as central is surrounded by others which are very different from itself, but which neverthe- less prop and support it, these subsidiary subjects are (as a rule) not officially recognised in the examinations for a degree. Every scientific man would agree that a student who can read French and German is better prepared for a scientific career than one who, with an equal knowledge of science, can read English only. Why not allow to the higher attainments greater weight ? Again, there can be ro doubt that a scientific essay or treatise written in good English tends more to the advancement of “natural knowledge” than if the facts and arguments are badly expressed. Why not recognise this fact, as the Depart- ment of Science and Art has now done, by giving credit in the Honour examinations for the style in which the essays of candi- dates are written ? By such steps we should, at all events, secure that the teacher of science who chooses to take some pains with the essays of his students, or who urges them to learn to read French and German easily, should not feel that his advice, however useful it might ultimately be, would damage rather than improve their chances of a high place in the examination for a degree in science. Thus, too, we should keep open in the student’s mind avenues by which he might attain to some interest in language and literature for their own sakes. Iam well aware of the objections which might be raised to such a scheme ; and though I do not myself attach great weight to them, I will now only insist that if they are valid that fact is an additional proof of the truth of a proposition, which I do not deny, viz. that it is not so much by directing the studies of each individual student, as by bringing together teachers and learners who are teaching and learning very different things, that, by a mental ‘‘law of exchanges,” the interests of all are widened. It is no doubt a weak point in a college such as ours that the range of instruction is limited to science and to some of its applications, and that thus you are all studying closely allied subjects. Union with other colleges in a university may help to remedy this defect. Meanwhile, all that can be done officially to promote general cultivation is small compared with what you can do for yourselves and for each other, and this because you are at liberty to embrace a wider range than any university would be justified in forcing upon you. Your success as specialists will largely depend upon your studies and your teachers. Your wider cultivation will chiefly be the work of your relaxations and your friends. Do not misunderstand me. In general, a young man with no physical defect will and ought to take an interest and a part in athletics. In a great metropolis this is even more necessary than in the case of universities which, like Oxford, Cambridge, St. Andrews or Gottingen, are comparatively in the country. I am proud to be the president of a Boat Club which this sum- mer won a race in a Thames regatta. I have been treasurer of two scientific societies, and am glad to be now the treasurer of the United Football Clubs of the engineering departments of the London Colleges. I hope and believe that these are the germs from which the athletic clubs of the future university will spring. I hope and believe that the undergraduates of that university will not differ from all other groups of young Englishmen in that, while engaged in the cultivation of intellect and taste, they neglect the cultivation of thews and sinews. But if it be granted that college work and college sports must fill up much of the time of all of you, there are still spare but precious moments in which you cannot indeed master, but may ward off, complete ignorance of things which have little to do with your studies or your sports, but are none the less worth knowing and loving. You have college societies where such things are discussed OcTOBER 19, 1&99] NATURE 601 and debated. They are described in the excellent little pamphlet which has been put in every freshman’s hand. You can at the least do what is in your power to attend and support them. You can take care that your undergraduate days do not pass without the great names of literature becoming more than names to you. Books can be had for the asking from public libraries, they can be bought for pence where they used to cost shillings. We owe to the generosity of Prof. Perry the nucleus of a college library containing books which are not scientific. He who now devotes to literary trash time which he might spend in learning something of one of the greatest literatures of the world has nobody but himself to thank if his reading vulgarises instead of refines him. Taste is educated only by tasting; and it rests with yourselves whether you will learn to appreciate the differ- ence between the great masters of the pen and penny-a-liners, between the wit of a great humourist and the vulgarities of the funny corner of a second-rate newspaper. A bicycle ride will be none the less enjoyable if you train yourself, not merely to travel far, but to take an interest in the sights and scenes through which you pass. For the sake of example, let me remind you that no country is so rich as England in the architecture of its village churches. It is. no hard matter to learn to recognise the principal peculiarities of the architectural types which prevailed from the days of the Saxons to Sir Christopher Wren. The text-books are, I presume, to be found in the Art Library. But as soon as the elements of English church architecture are known, an old church ceases to be merely a picturesque object. It is an historical document which you yourself can read. You do not need the aid of the sexton to tell you which is the oldest part. You can make a good guess at when that aisle was added, or that window knocked in a wall obviously older than itself. A visit to a cathedral becomes an intellectual pleasure. Weariness at the drone of the verger as he recites his oft-repeated lesson is ceplaced by an alert desire to know if the authorities from whom he learnt it confirm or correct the rapid conclusions as to date or history to which you yourself have come. I might multiply such examples. Nowhere in England can you so easily or so cheaply as in London hear and learn to appreciate the best music the world has produced. The wet half holidays of an undergraduate’s career well spent in the National Gallery would give you a familiarity with all the great schools of painting which few travellers attain. Every day as you come to or leave your work you may pass through one of the greatest art collections in the world, and it depends upon you alone as to whether you shall or shall not Jearn anything from it. Understand me clearly when I reiterate that I am laying down no rules. I have tried only to lay the problem before you. How to combine the proper care for pounds, shillings, and pence with the love of knowledge for its own sake ; how best to balance your various studies ; how to add to the concentration required yor the mastery of a single subject the open eye and the refined taste which may lead you to appreciate arts which you cannot emulate, and things beautiful which you can neither copy nor produce ; these are problems in which a university may help you, but can help you only if you are willing to help yourselves. I have to-day aimed at nothing more than at reminding you that each one of the mental forces we have discussed is essential to the equilibrium of intellectual life ; that if you wilfully neglect any of them, or devote yourselves too exclusively to one, you will iall short, and, it may be, sadly short, of the ideal which the true university holds up to her sons. FORTHCOMING BOOKS OF SCIENCE. M R. EDWARD ARNOLD'S list includes :—‘‘ Dynamics for 2 Engineering Students,” by Prof. W. E. Dalby ; ‘* Physical Calculus,” by Percy E. Bateman; ‘‘ Text-book of Physical Chemistry,” by Dr. R. A. Lehfeldt ; ‘*A Manual of Elementary Chemistry,” by W. A. Shenstone, F.R.S. ; ‘‘ Magnetism and Electricity,” by J. Paley Yorke ; ‘‘A Manual of Botany,” by David Houston; ‘f A Manual of Physiography,” by Dr. Andrew J. Herbertson ; ‘A Text-book of Domestic Science,” by Mrs. S. J. Shaw; ‘Elementary Natural Philosophy,” by Alfred Earl; ‘Wood: its Natural History and Industrial Applic- ations,” by Prof, G. S. Boulger ; ‘‘ The Dressing of Minerals,” by Prof. Henry Louis ; and a new edition of ‘* Animal Life and Intelligence,” by Prof. C. Lloyd Morgan, F.R.S. NO. 1564, VOL. 60] The list of Messrs. Bailliére, Tindall, and Cox contains :— ‘Dictionary of French-English Medical Terms,” by H. De Meric ; ** The X-ray Case-book for Noting Apparatus, Methods and Results, with Full Diagrams of the Human Body,” by Dr. D. Walsh; ‘‘The Pathological Statistics of Insanity,” by Francis O, Simpson; ‘‘ Difficult Digestion due to Displace- ments,” by Dr. A. Symons Eccles; ‘‘ An Introduction to the Diseases of the Nervous System,” by Dr. H. Campbell Thom- son; ‘fA Manual for Nurses,’’ by Florence Haig-Brown “The Artistic Anatomy of the Horse,” by Dr. U. W. Arm- stead, illustrated ; ‘* Statistics of Food Adulteration and Sug- gested Standards,” by C. G. Moor and C, U. Cribb; and new editions of ‘* A Synopsis of the British Pharmacopceia, 1898,” compiled by H. Wippell Gadd, with Analytical Notes and Sug- gested Standards, by C. G. Moor. ‘‘ Practical Guide to the Public Health Acts. A Vade Mecum for Officers of Health and Inspectors of Nuisances,” by Dr. T. Whiteside Hime ; ‘‘ Manual of Surgery for Students and Practitioners,” by Drs. W. Rose and A. Carless ; “‘ Heart Disease, with Special Reference to Prog- nosis and Treatment,” by Sir W. I!. Broadbent, Bart, M.D, F.R.S., and Dr. J. F. H. Broadbent; ‘‘ Practical Horse- Shoeing,” by Dr. George Fleming. In Messrs. G. Bell and Sons’ list we find :—‘‘ Comparative Physiology,” by G. C. Bourne ; ‘‘ Physiography,” by H. N. Dickson ; ‘* Chemistry,” by Prof. James Walker ; ‘f Mechanics,” by Prof. G. M. Minchin, F.R.S.; ‘‘ Electricity and Mag- netism,” by Prof. Oliver J. Lodge, F.R.S.; “ Elementary General Science,” by D. E. Jones and D S. McNair. ‘A Short Course of Elementary Plane Trigonometry,” by Charles Pendlebury. In Messrs. A. and C. Black’s list are :—‘‘ Newton’s Laws or Motion,” by Prof. P. G. Tait ; ‘* A Text-Book of Zoology,” by Prof. E. Ray Lankester, F.R S. The list of Messrs. Blackie and Son, Ltd., includes :— “Among the Birds in Northern Shires,” by Charles Dixon ; ‘© A Book of Birds,” by Carton Moore Park, illustrated. Messrs. W. Blackwood and Sons promise :—‘‘ Practical Nursing,” by Isla Stewart and Dr. Herbert E. Cuff ; ** Physical Maps for the Use of History Students,” by Bernhard V. Darbi- shire ; ‘‘ A Manual of Classical Geography,” by John L. Myres ; ‘* Exercises in Geometry,” by J. A. Third. Messrs. Gebriider Borntraeger (Berlin) will publish :—‘‘ Eine Landschaft der Steinkohlen-Zeit,’’ by Dr. H. Potonié. Mr. T. Burleigh announces :—*‘ Our Common Cuckoos, other Cuckoos and Parasitical Birds,” by Dr. Alexander Japp. The announcements of the Cambridge University Press in- clude :—*‘ Scientific Papers,” by Prof. P. G. Tait, vol. ii ; ‘* The Scientific Papers of John Couch Adams,” vol. ii, edited by Prof. W. G. Adams, F.R.S., andi R. A. Sampson; ‘‘ Scientific Papers,” by Lord Rayleigh, F.R.S.; ‘‘ Scientific Papers,” by the late Dr. John Hopkinson, F.R.S., in 2 vols. ; ‘‘ Scientific Papers,” by Prof. Osborne Reynolds, F.R.S.; ‘* Aether and Matter,” a development of the relations of the aether to material media, including a discussion of the influence of the earth’s motion on the phenomena of light; being one of two essays to which the Adams prize was adjudged in 1899 in the University of Cambridge, by Dr. Joseph Larmor, F.R S. ; ** Aberration,” a study of the relations between the ether and matter : being one of two essays to which the Adams prize was adjudged in 1899 in the University of Cambridge, by G. T. Walker ; ‘‘The Theory of Differential Equations,” part ii., ordinary equations, not linear, by Prof. A. R. Forsyth, F.R.S., in 2 vols.; ‘‘The Strength of Materials,” by Prof. J. A. Ewing, F.R.S. ; ‘‘A Treatise on the Theory of Screws,” by Prof. Sir Robert S. Ball, F.R.S. ; ‘* A Treatise on Geometrical Optics,” by R. A. Herman; ‘‘ Zoological Results based on material from New Britain, New Guinea, Loyalty Islands and elsewhere, collected during the years 1895, 1896 and 1897, by Dr. Arthur Willey, part iv., illustrated ; *‘ Fauna Hawaiiensis, or the Zoology of the Sandwich Islands,” being results of the explorations instituted by the joint committee appointed by the Royal Society of London for promoting natural knowledge and the British Association for the Advancement of Science, and carried on with the assistance of those bodies and of the Trustees of the Bernice Pauahi Bishop Museum, edited by Dr. David Sharp, F.R.S.; vol. ii., part i., Orthoptera, by R. C. L. Perkins ; vol. il., part ii., Neuroptera, by R. C. L. Perkins ; ‘* Fossil Plants,” by A. C. Seward, F.R.S., vol. ii. ; ‘* Elec- tricity and Magnetism,” by R. T. Glazebrook, F.R.S. ; “Crystallography,” by Prof. W. J. Lewis; ‘‘ Military 602 NATURE [OcrosER 19, 1899 Geography,” by Dr. T. M. Maguire; ‘*The Teaching of Geography in Switzerland and North Italy,” by J. B. Reynolds ; “* Educational Aims and Methods,” lectures and addresses by Sir Joshua Fitch ; ‘The Teacher’s Manual of School Hygiene,” by Dr. E. W. Hope and E. Browne; ‘‘ A New Primer of Astronomy,” by Prof. Sir Robert S. Ball, F.R.S.; ‘“A New Primer of Mechanics,” by L. R. Wilberforce; ‘‘ A New Primer of Physics,” by the same author; ‘‘A New Primer of Chemistry,” by F. H. Neville : ‘‘ A New Primer of Physiology,” by Dr. Alex. Hill; ‘‘ A Brief History of Geographical Dis- covery since 1400,” by Dr. F. H. H. Guillemard; ‘* An Introduction to Physiography,” by W. N. Shaw; ‘‘ Euclid. Books I-III with simple exercises,” by R. T. Wright ; ‘© Geometrical Drawing,” by W. H. Blythe. ae Messrs Cassell and Co,’s list contains :—‘‘ Our Rarer British Breeding Birds, their Nests, Eggs and Breeding Haunts,’ by Richard Kearton, illustrated ; ‘‘ Familiar Wild Flowers,” by F. E. Hulme, new vol., illustrated ; ‘‘ A Practical Method of Teaching Geography,” by J. H. Overton, vol. ii. ; and a new edition of ‘* Starland,” by Prof. Sir R. S. Ball, F.R.S. Messrs. W. and R. Chambers will publish :—‘‘ Commercial Geography,” by Dr. A. J. Herbertson. Among the books in preparation at the Clarendon Press may be mentioned :—‘‘ Physical Aspects of Soils,” by Prof. Robert Warington, F.R.S.; ‘‘A Catalogue of Eastern Lepidoptera Heterocera in the Oxford University Museum,” by Colonel C. Swinhoe (Part II., Noctuina); Authorised Translations of Pleffer’s ‘* Pflanzenphysiologie,” by Dr. A. G. Ewart, and Goebel’s ‘‘ Pflanzenorganographie,” by Prof. I. Bayley Balfour, F.R.S. The Columbus Company, Ltd., promise :—‘‘A Series of Servian Folk-lore Stories,” by Elodie L. Mijatovich. Messrs. Archibald Constable and Co. give notice of :— “Art Enamelling upon Metals,” by H. H. Cunynghame, illus- trated ; ‘‘ Auto-Cars and Horseless Carriages,” by Dugald Clerk and Worby Beaumont, illustrated ; ‘‘ Acetylene Gas,” by Prof. Vivian B. Lewes, illustrated; ‘‘The Simplest Living Things,” by Prof. E. Ray Lankester, F.R.S.; ‘‘ The Victoria History of the Counties of England : Hampshire,” in which the various branches of Science will be dealt with-by specialists. Messrs. Dean and Son, Ltd., will issue :—‘‘ Guide to Queens- land,” by C. S. Rutlidge. Mr. David Douglas (Edinburgh) announces :—‘‘ The Mineral- ogy of Scotland,” by the late Prof. M. Forster Heddle, edited by J. G. Goodchild; ‘‘A Vertebrate Fauna of the Shetland Islands,” by A. H. Evans and T. E. Buckley, illustrated ; “‘ Among British Birds in their Nesting Haunts,” by O. A. J. Lee. Part 16, illustrated. Messrs. Duckworth and Co.’s list contains :—‘‘ A Glossary of Botanic Terms,” by Benjamin Daydon Jackson ; ‘‘ Agricul- tural Botany, Theoretical and Practical,” by John Percival ; **Country Matters in Short,” by William Frederick Collier. Mr. W. Engelmann (Leipzig) announces :—‘‘ Darstellung der 32 moglichen Krystallklassen,” by Prof. Baumhauer, illustrated ; **Die Lepra des Auges,” by Dr. Borthen, illustrated; ‘‘ Der Briickenbau,” Erste Abteilung, edited by Prof. Th. Landsberg ; ** Neue Briickenbauten in Osterreich und Ungarn,” by Prof. Foerster, illustrated; ‘‘ Monographien afrikanischer Pflanzen- Familien und-Gattungen,” edited by Prof. A. Engler; III. ‘‘ Combretaceae-Combretum,” by A. Engler and L. Diels ; I. “Moraceae,” by A. Engler; II. ‘* Melastomaceae,” by E. Gilg, illustrated; ‘‘ Abriss der darstellenden Geometrie,” by Prof. Gerland ; ‘‘Conspectus Florae Graecae,” by Dr. Halacsy, 1 Lieferung; ‘‘Strahlung und Temperatur der Sonne,” by Prof. Scheiner, Mr. S. T. Freemantle will publish a new library edition of the works of Gilbert White, including the ‘‘ Natural History of Selborne,” under the general editorship of Dr. Bowdler Sharpe, illustrated. Messrs. R. Friedlander and Son (Berlin) promise :—‘‘ Das Tierreich,” edited for the German Zoological Society by Fr. E. Schulze ; ‘‘ Lieferung 9: Trochilide,” by E. Hartert: ‘‘ Sys- tematische Uebersicht der Ergebnisse seiner Reisen und schrift- stellerischen Thatigkeit (1859-1899), by G. Finsch. Messrs. Gauthier-Villars et Fils (Paris) promise :—‘‘ Lecons sur la Théorie des Formes ex la Géométrie analytique supérieure,” by Andoyer; ‘La Télégraphie sans fil,” by Broca ; ‘‘Elémentes de la Théorie des nombres,” by Cahen ; **De Paris aux mines d’or d’australié,” by Chemin; ‘ Re- cherches sur les réseaux,” by Quesneville; ‘*Traité pratique NO. 1564, VOL. 60] de Photogravure en relief et en creux,” by Vidal; ‘ Traité optique géométrique,” by Wallon; ‘‘l'Objectif Photo- oe by Lieut.-Colonel P. Moéssard; ‘‘iuvres cientifiques,” by Louis Raffy : — Mathématiques: Nouvelle théorie des fonctions exclusivement fondée sur Vidée de nombre. Physique: Physique mathématique (Distribution de l'Electricité, Hydrodynamique, Fragments divers), Thermo- dynamique générale (Equilibre et modifications de la matiére), Chimie: Lecgons de Chimie physique. ‘‘Essai des huiles essentielles,” by H. Labbé; ‘‘La Métrophotographie,” by Colonel A. Laussedat; ‘‘La Photocollographie,” by G. Balagny ; ‘‘ Progres de 1’Electricité. Oscillations hertziennes. Rayons cathodiques et rayons X,” by Prof. E. Bouty; ‘La Chronophotographie,” by J. Marey; ‘‘Sur.quelques Progres récents accomplis avee l'aide de la Photographie dans l’étude du Ciel,” by Dr. P. Puiseux; and a new edition of ‘‘ Dis- tribution de la vapeur. Epures de régulation. Courbes d'indicateur. Tracé des diagrammes,”’ by A. Madamet. Mr. L. Upcott Gill announces :—‘‘ British Dragonflies,” by W. J. Lucas, illustrated :—‘‘ The Book of Gardening,” a further supplement to Nicholson’s Dictionary of Gardening. The scientific announcements of Messrs. C. Griffin and Co., Ltd., are :—‘‘ Outlines of Bacteriology,” by Dr. L. H. Thoinot and E. J. Masselin, translated and adapted for English use, with additions, by Dr. Wm. St. Clair Symmers, illustrated ; ‘‘ Dairy Chemistry for Dairy Managers, Chemists and Analysts,” by H. D. Richmond ; ‘‘ Lubrication and Lubricants: a Treatise on the Theory and Practice of Lubrication and on the Nature, Properties and Testing of Lubricants,’ by Leonard Archbutt and R. Mountford Deeley; ‘‘The Metallurgy of Lead and Silver,” by H. F. Collins, in 2 vols., each complete in itself, Part i.—Lead, Part ii.—Silver; ‘‘A Dictionary of Textile Fibres,” by W. J. Hannan, illustrated ; ‘‘ Marine Meteorology,” for officers of the merchant navy, by William Allingham, illus- trated ; ‘‘ New Lands and their Prospective Advantages,” by Dr. H. R. Mill; “ Building Construction in Wood, Stone and Concrete,” by James Lyonand J. Taylor ; and a new edition of “Clinical Medicine: a Practical Handbook for Practitioners and Students,” by Dr. Judson Bury, illustrated. Mr. Heinemann’s list includes:—‘‘The Life of William Cotton Oswell,” by his Son, W. E. Oswell, illustrated ; ‘‘ Inner- most Asia: a Record of Travel and Sport in the Pamirs,” by Ralph P. Cobbold, illustrated ; ‘* The World in 1900,” a New Geographical Series, edited by H. J. Mackinder : (1) ‘‘ Britain and the North Atlantic,” by the Editor ; (2) ‘‘ Scandinavia and the Arctic Ocean,” by Sir Clements R. Markham, K.C.B., F.R.S.: (3) ‘“‘The Mediterranean and France,” by Prof. E. Reclus ; (4) ‘‘ Central Europe,” by Prof. J. Partsch; (5) ‘‘ Africa,” by Dr. J. Scott Keltie ; (6) ‘* The Near East,” by D. G. Hogarth ; (7) ‘The Russian Empire,” by Prince Kropotkin; (8) ‘‘ The Far East,” by Archibald Little; (9) ‘‘ India,” by Colonel Sir Thomas Holdich ; (10) ‘‘ Australasia and Antarctica,” by Dr. H. O. Forbes ; (11) ‘‘ North America,” by Prof. I. C. Russell ; (12) ‘South America,” by Prof. J. C. Branner. ‘* Telephoto- graphy: an Elementary Treatise on the Construction and Application of the Telephotographic Lens,” by T. R. Dallmeyer, illustrated. Among Messrs. Hutchinson’s new books may be mentioned, “The Living Races of Mankind,” by the Rev. H. N. Hutchin- son, Dr. J. W. Gregory, and R. Lydekker, F.R.S.; “* Disciples of ésculapius,” by the late Sir Benjamin Ward Richardson, F.R.S., with a biography of the writer by his daughter. The Junior Army and Navy Stores give notice of ‘‘The Western Rajputana States, a Medico-Topographical and General Account of Marwar, Sirohi, Jaisalmir,” by Lieut.-Colonel A. Adams. Mr. John Lane calls attention to ‘‘ The Natural History of Selborne,” by Gilbert White, edited by Grant Allen, illustrated ; ** All About Dogs,” by Charles Henry Lane, illustrated; ‘‘A Child’s Primer of Natural History,” by Oliver Herford, illus- trated. Messrs. Longmans and Co. announce new editions of ‘‘ The Kinetic ‘Theory of Gases,” Elementary Treatise with Mathe- matical Appendices, by Prof. Oskar Emil Meyer, translated by: R. E. Baynes, and ‘‘ Coats’ Manual of Pathology.” The list of Messrs. Sampson Low and Co,, Ltd., includes :— ‘* Experts on Guns and Shooting,” by G. T. Teasdale Buckell, illustrated: ‘* Twentieth Century Practice, an International Encylopedia of Modern Medical Science by leading Authorities of Europe and America,’’ edited by Dr. Thomas L, Stedman. OcToBER 19, 1899] NATURE 603 In 20 vols., vol. xix., ‘© Tuberculosis and Leprosy” ; vol. xx., “Syphilis and General Index ;” and new editions of “‘ Instruc- tions in Photography,” by Captain W. de W. Abney, F-.R.S. ; “A Key to Engines and Engine Running,” by J. Rose. | In the list of Messrs. Macmillan and Co., Ltd., we notice :— **Life and Letters of Thomas Henry Huxley, F.R.S.,’ by Leonard Huxley, with portraits and illustrations, 2 vols ; ‘‘ Life of James Hack Tuke,” by the Right Hon. Sir Edward Fry, F.R.S., with portrait; ‘‘ Notes on Sport and Travel,” by the late Dr. George Kingsley, with introductory memoir by his daughter, Mary H. Kingsley, with portrait ; ‘‘ Malay Magic ; being an Introduction to the Folklore and Popular Religions of the Malay Peninsula,” by W. W. Skeat, illustrated; ‘‘A History of Modern Philosophy,” by Dr. Harald Hoffding, translated from the German by B. E. Meyer, 2 vols. ; ‘‘ The Social Philosophy of Rodbertus,” by E. C. K. Gonner ; ‘‘ A Manual of Zoology,” by the late Prof. T. J. Parker, F.R.S., and Prof. W. A. Has- well, F.R.S., illustrated ; ‘‘ Elementary Practical Zoology,” by the late Prof. T. J. Parker, F.R.S., and Prof. W. Newton Parker, illustrated; ‘‘ Elements of ‘‘ Paleontology,” by Prof. Karl A. von Zittel, translated and edited by Dr. Chas. R. Eastman, illustrated (this English edition is revised and en- larged by the author and editor in collaboration with numerous Specialists) ; ‘* Introduction to Physical Chemistry,” by Prof. James Walker ; ‘‘ Dictionary of Political Economy,” edited by R. HH. Inglis Palgrave, F.R.S., vol. iii. (completing the work) ; “* Micro-organisms and Fermentation,” by Alfred Jorgensen, translated by Dr. Alex. K. Miller and E. A. Lennholm, illustrated ; ““A System of Medicine,” by many writers, edited by Prof. Thomas Clifford Allbutt, F.R.S., vol. viii. (concluding the work) ; ‘‘ An Introduction to the Study of Mental Affections,” by Dr. John Macpherson ; ‘ Introduction to the Outlines of the Principles of Differential Diagnosis, with Clinical Memoranda,” by Dr. Fred. J. Smith; ‘* A Manual of Medicine,” edited by Dr. W. H. Allchin, in five vols. ; ‘‘A Manual of Surgery,” by Chas. Stonham, in three vols, ; ‘“‘ Experimental) Physiography for Section I, Physiography of the Science and Art Department,” by Prof. R. A. Gregory and A. T. Simmons; ‘‘ Building Construction for Beginners,” by J. W. Riley; ‘‘ Chemistry for Organised Schools of Science,” by S. Parrish; ‘‘ A Treatise on Elementary Dynamics, dealing chiefly with Motion in Two Dimensions,” by H. A. Roberts ; ‘* Dictionary of Philosophy,” edited by Prof. J. Mark Baldwin; ‘‘ Methods of Knowledge,” by Walter Smith; ‘‘First Experiments in Psychology,” by Prof. Titchener ; ‘‘ The Hygiene of the School and of Instruction,” by Edward R. Shaw; ‘‘ Method in Education,” by Walter L. Hervey ; ‘‘ The Study and Teaching of Geography,” by Jacques W. Redway ; ‘“‘The Study and Teaching of Mathematics,” by Principal David Eugene Smith ; ‘‘ Elementary Chemistry,” by A. L. Arey; **An Encyclopedia of American Horticulture,” by L. H. Bailey, in 3 vols. ; ‘‘ Practical Garden Book,” by L. H. Bailey; “Irrigation,” by Prof. F. H. King; ‘‘ Thermo- dynamics,” by E. Buckingham ; ‘‘The Teaching Botanist,” by Prof. William F. Ganong ; ‘‘ Elementary Electricity and Mag- netism,” by D. C. Jackson and J. P. Jackson; ‘* The Myxo- mycetes, a Handbook of North American Slime Moulds,” by Prof. Macbride ; ‘‘Imperative Surgery, for the General Prac- titioner, the Specialist, and the Recent Graduate,” by Dr. Howard Lilienthal; and a new edition of ‘*An Atlas of Practical Elementary Biology,” by Prof. G. B. Howes, F.R.S. Messrs. Methuen and Co. give notice of :—‘‘ The Scientific Study of Scenery,” by J. E. Marr, F.R.S. ; ‘*A Handbook of Nursing,” by M. N. Oxford ; ‘* Practical Physics,” by Prof. H. Stroud ; ‘‘ General Elementary Science,” by Dr. J. T. Dunn and V. A. Mundella, illustrated ; ‘‘The Metric System,” by Leon Delbos ; “‘ The Highest Andes,” by E. A. Fitzgerald, illustrated. Mr. Murray will issue in his Progressive Science Series :— ‘*On Whales,” by F. E. Beddard, F.R.S., and ‘‘ Heredity,” by Prof. J. A. Thomson, He also announces :—‘‘ The Yang-Tse Valley and Beyond,” by Mrs. Bishop, illustrated ; ‘* A Glimpse at Guatemala, and some Notes on the Ancient Monuments of Central America,” by Annie Cary Maudslay and Alfred Percival Maudslay, illustrated ; ‘‘ Preparatory Geography for Irish Schools,” by John Cooke, coloured and relief maps ; ‘‘ The Making of a Frontier, Five Years’ Experiences and Adventures in Gilgit, Hunza Nagar, Chitral, and the Eastern Hindu-Kush,” by Colonel Algernon Durand, illustrated ; and a new edition of ““The Natural History of Religion, based on the Gifford Lec- tures delivered in Aberdeen in 1889-90 and in 1890-91,” by Prof. E. B. Tylor, F.R.S., illustrated. NO. 1564, VOL. 60] Messrs. George Newnes, Ltd., announce :—‘‘The Story o. some Wandering Atoms, especially those of Carbon,”’ by M. M. Pattison Muir; ‘* The Story of Life’s Mechanism,” by H. W. Conn; ‘* The Story of Thought and Feeling,” by F. Rylands ; “The Story of the Alphabet, with a brief account of some Ancient Records,” by Edward Clodd, illustrated. Mr. David Nutt’s list contains:—‘‘ Problems of the Mycenzean Age,” by H. R. Hall; ‘‘ Egyptian Chr-nology,” by F. G. Fleay. Messrs. G. P. Putnam’s Sons announce :—‘‘ Nature Studies in Berkshire,” by the Rev. S. Coleman Adams, illustrated ; ‘* Birds that Hunt and are Hunted,’ by Neltje Blanchan, illustrated. Messrs. Sands ard Co. announce :—‘‘ Picturesque Kashmir,” by Dr. A. Reve, with a chapter entitled ‘‘The Shaping of Kashmir,” being a description of the geological formation and aspects of the country, illustrated ; ‘‘ Types of British Animals,” by F. G. Aflalo, illustrated ; ‘‘ The Animals of Africa,” by H. A. Bryden, illustrated ; ‘‘ Types of British Plants,” by C. S, Colman, illustrated. Messrs. Walter Scott, Ltd., will add to the Contemporary Science Series ‘* The Races of Man: a sketch of Ethnography and Anthropology,” by Dr. J. Deniker ; and ‘* The Psychology of Religion,” by Prof. Starbuck, each illustrated. Messrs. Smith, Elder and Co. promise :—‘“* Tlealth Abroad, a Medical Handbook for Travellers,” edited by Dr. Edmund Hobhouse ; Orthopeedic Surgery,” by C. B. Keetley, illustrated ; “* Lectures on the Practice of Medicine,” by Dr. W. B. Cheadle, illustrated. The science list of Messrs. Swan Sonnenschein and Co., Ltd., is as follows :—“‘ The Victoria Nyanza : the Land, the Races and their Customs with specimens of some of their Dialects,” by Lieut. P. Kollmann, illustrated ; ‘‘ The Antarctic,” by Dr. K. Fricker, illustrated ; ‘* Aristotle’s Psychology, including the Parva Naturalia,” translated and edited with commentary and intro- duction by Prof. William A. Hammond; ‘‘A History of Contemporary Philosophy,” by Prof. Max Heinze, translated by Prof. William Hammond ; ‘‘ Ethics,” by Prof. W. Wundt, vol. iii. : ‘* The Principles of Morality and the Sphere of their Validity,” translated by Prof. E. B. Titchener ; ‘* Physiological Psychology,” by Prof. W. Wundt, translated by Prof. E. B. Titchener, 2 vols. illustrated; ‘*The Scientific Basis of Morality,” by Dr. G. Gore, F.R.S,; ‘‘ Text-book of Palz- ontology for Zoological Students,” by Theodore T. Groom, illustrated ; ‘‘ Text-book of Embryology: Invertebrates,” by Profs. E. Korschelt and K. Heider, vol. iii., translated from the German by Mrs. H. M. Bernard, and edited (with additions) by Martin J. Woodward, illustrated; ‘*‘ Mammalia,” by the Rey. H. A. Macpherson ; ‘‘ Birds’ Eggs and Nests,” by W. C. J. Ruskin Butterfield; and new editions of ‘‘ Handbook of Practical Botany for the Botanical Laboratory and_ private Students,” by Prof. E. Strasburger, edited by Prof. W. Hill- house, illustrated; ‘‘ An Introduction to Zoology,” by B. Lindsay, illustrated; ‘‘The Dog: its Management and Diseases,” by Prof. Woodroffe Hill, illustrated; and ‘‘Intro- duction to the Study of Physiological Psychology,” by Prof. Th. Ziehen, translated and edited by Dr. O. Beyer and C. CG. Vanliew, with diagrams. The list of the S.P.C.K. contains a new edition of ‘The Bible Atlas of Maps and Plans to illustrate the Geography of the Old and New Testaments, and the Apocrypha,” with ex- planatory notes by the late Rev. Samuel Clarke, and a complete index of the geographical names in the English Bible, by Sir George Grove. Mr, Edward Stanford will issue :—‘‘ Europe, Vol. i., the Countries of the Mainland (excluding the North-West),” by George G. Chisholm, illustrated; ‘The Evolution of Geo- graphy, a Sketch of the Rise and Progress of Geographical Knowledge,” by John Keane, illustrated. Mr. T. Fisher Unwin calls attention to:—‘‘ Hermann Von Helmholtz,” by Prof. J. G. McKendrick, F.R.S. ; ‘* Experi- ments on Animals,” by Dr. S. Paget; ‘‘In Dwarf-Land and Cannibal Country,” by A. B. Lloyd, illustrated ; ‘‘ From the Alps to the Andes,” by M. Zurbriggen, illustrated. Messrs. Frederick Warne and Co. promise :—‘‘ The Flowering Plants, Grasses, Sedges and Ferns:of Great Britain,” by Anne Pratt, edited and revised by Edward Step ; ‘‘The Romance of Wild Flowers,” by Edward Step, illustrated. Messrs. Whittaker and Co.’s announcements are :—‘‘ Central Station Electricity,” by A. Gay and C. H. Yeaman; ‘‘ Arc 604 Lamps,” by H. Smithson and E. R. Sharp; ‘‘ English and American Lathes,” by Joseph Horner ; ‘‘ Inspection of Railway Materials,” by G. R. Bodmer ; ‘‘ The Modern Safety Bicycle,” by H. A. Garratt ; ‘‘ Volumetric Chemical Analysis,” by J. B. Coppock ; ‘‘ Elementary Practical Chemistry,” by A. J. Cooper ; new and revised editions of ‘‘The Atlantic Ferry,” by A. J. Maginnis; ‘‘ British Locomotives,” by C. J. Bowen-Cooke ; ‘© Electric Light Cables,” by Stuart A. Russell. THE BRITISH ASSOCIATION. SECTION Kk. BOTANY. OPENING ADDRESS BY SIR GEORGE KING, K.C.LE., LL.D., F.R.S., PRESIDENT OF THE SECTION. Il. THE second period of our history begins with the arrival in India in 1848 of Sir (then Dr.) Joseph Hooker. This dis- tinguished botanist came out in the suite of Lord Dalhousie, who had been appointed Governor-General of India. The province to the exploration of which Sir Joseph directed his chief attention was that of Sikkim in the Eastern Himalaya, the higher and inner ranges of which had never previously been visited by a botanist, for Griffith’s explorations had been confined to the lower and outer spurs. The results of Sir Joseph’s labours in Sikkim were enormous. Towards the end of his exploration of Sikkim he was joined by Dr. Thomas Thomson, and the two friends sub- sequently explored the Khasia Hills (one of the richest collecting grounds in the world), and also to some extent the districts of Sylhet, Cachar and Chittagong. Dr. Thomson subsequently amalgamated the collections made by himself in the Western Himalaya with those made in Sikkim by Sir Joseph individually, and by them both conjointly in Eastern India ; and a distribu- tion of the duplicates after the fashion of the Wallichian issue, and second only to it in importance, was subsequently made from Kew. The number of species thus issued amounted to from 6000 to 7000, and the individuals were much more numerous than those of the Wallichian collection. The imme- diate literary results of Sir Joseph Hooker’s visit to Sikkim were (1) his superbly illustrated monograph of the new and magnificent species of Rhododendron which he had discovered ; (2) a similar splendid volume illustrated by plates founded on drawings of certain other prominent plants of the Eastern Himalaya which had been made for Mr. Cathcart, a member of the Civil Service of India, and (3) his classic ‘* Himalayan Journals ””—a book which remains until this day the richest repertory of information concerning the botany, geography and anthropology of the Eastern Himalaya. A remoter result was the appearance in 1855 of the first volume of a “‘ Flora Indica,” projected by himself and his friend Dr. Thomson. The first half of this volume is occupied by a masterly introductory essay on Indian botany, of which it is hardly possible to overrate the importance. This remarkable essay contains by far the most important contribution to the physico-geographical botany of India that has ever been made, and it abounds in sagacious observations on the limitation of species and on hybridisation, besides containing much information on the history of Indian botanical collections and collectors. The taxonomic part of the book was cast in a large mould, and the descriptions were written in Latin. Unfortunately, the condition of Dr. Thomson’s health and the pressure of Sir Joseph’s official duties at Kew made it impossible that’ the book should be continued on the magnificent scale on which it had been conceived. After a period of about twelve years Sir Joseph, however, returned to the task of preparing, with the aid of other botanists, a Flora of the Indian Empire, conceived on a smaller scale and written in the English language. THis proposals for this work were accepted and officially sanctioned by the Duke of Argyll while he was Secre- tary of State for India. The first part of this great work was published in 1872 and the last in 1897. In the execution of this great undertaking Sir Joseph had the assistance of Mr. C. B. Clarke, who elaborated various natural orders; of Mr. J. G. Baker, who worked out Legumznosae and Scztamzneae, and of Sir W. Thiselton-Dyer, Messrs. A. W, Bennett, Anderson, 1 Continued from p. 584. NO. 1564, VOL. 60] NATURE [OcroBER 19, 1899 Edgeworth, Hiern, Lawson, Maxwell Masters, Stapf and Gamble. The greater proportion, however, of the book is Sir Joseph’s own work, and a noble monument it forms of his devotion and genius. Since the date of Sir Joseph Hooker’s visit to India, by far the most important botanical work done in India has been that of Mr.C. B. Clarke. Rather than attempt to give any appreci- ation of my own of Mr. Clarke’s labours (which would be more or less of an impertinence), I may be allowed to quote from the preface to the concluding volume of the ‘‘ Flora of British India ”’ Sir Joseph’s Hooker’s estimate of them. Referring to all the collections received at Kew since the preparation of the “* Flora”? was begun, Sir Joseph writes: ‘* The first in import- ance amongst them are Mr. C. B. Clarke’s, whether for their extent, the knowledge and judgment with which the specimens were selected, ticketed, and preserved, and for the valuable observations which accompany them.” Mr. Clarke has pub- lished numerous papers on Indian botanical subjects in the journals of the Linnean and other societies. He has issued as independent books monographs of Indian Covfosttae and Cyrtandraceae, the former in octavo, the latter in folio, and illustrated by many plates ; and he is now engaged on his ofzas maxzmum, viz. a monograph of the Cyferaceae, not only of India, but of the whole world ; and to the completion and pub- lication of this every systematic botanist is looking forward with eager anxiety. During this second half of the century, Dr. Thomas Anderson, who was for ten years superintendent of the Calcutta Garden, collected much ; and he had just entered on what promised to be a brilliant career of botanical authorship when his life was cut short by disease of the liver, contracted during his labours to establish the cultivation in British India of the quinine-yielding species of cinchona. Dr. Anderson was also the earliest conservator of forests in Bengal. Sulpiz Kurz, for many years curator of the Calcutta Herbarium, also collected largely in Burma, and besides many excellent papers which he contributed to the J/ouznal of the Asiatic Society of Bengal, he prepared for Government an excellent manual entitled the “Forest Flora of Burma.” This was published in two volumes in 1877. Other collectors in Burma were Colonel Eyre (in Pegu), Mr. Burness (at Ava), and the Rev. Mr. Parish, to whom horticulturists are indebted for the introduction to Europe of the beautiful orchids of this rich province. And in this con- nection must be mentioned Mr, E. H. Man, C.I.E., who, although not himself a botanist, has given for many years past the greatest possible help in the botanical exploration of the Andaman and Nicobar groups of islands, our first knowledge of which was, by the way, derived from the collections made by the naturalists of the Austrian and Danish exploring expeditions. A large book on Burma, which contains a good deal of botany, was published by an American missionary named Mason, who resided for the greater part of his working life in that country. General Sir Henry Collett, who commanded a brigade during the last Burmese war, also made most interesting collections in that country, the novelties of which were described by himself in collaboration with Mr. W. Botting Hemsley, of the Kew Herbarium, in the Linnean Society’s /owsna/ some years agoc Sir Henry Collett also collected much in the Khasia and Naga hills, and in the portion of the North-western Himalaya of which Simla is the capital, and on these latter collections, together with the materials in Kew Herbarium, Sir Henry is now elaborating a local flora of Simla. The preparation of a local flora for an Indian district is an entirely new departure, and the publication of Sir Henry’s book, which is to be well illus- trated, is looked forward to with muchinterest. At ratheran earlier period, Dr. Aitchieson was a diligent collector of the plants of the Punjab and of the North-western Frontier. Some results of his work are to be found in his ‘* List of Punjab Plants,” which was published in 1867, and in various papers which he contri- buted (some of them in conjunction with Mr. Hemsley) to the Linnean Society and to the Botanical Society of Edinburgh. In Dr. G. Henderson’s book on Yarkand there are also de- scriptions of some plants of the extreme North western Hima- laya and of Western Tibet. Mr. (now Sir George) Birdwood also made some contributions to the botany of the Bombay Presidency. Five officers of the Indian Forest Department, viz. Dr. Lindsay Stewart, Colonel Beddome, Sir D. Brandis, and Messrs. Talbot and Gamble, have within the past thirty years made im- portant contributions to the systematic botany of India. Dr. OcTOBER 19, 1899] NATURE 605 Stewart collected largely, and published in 1869 his ‘‘ Punjab Plants,” a book which gives a very imperfect impression of his acquirements as a botanist. Sir Dietrich Brandis issued in 1874 his admirably accurate “‘ Forest Flora of the North-west Provinces of India,” illustrated by seventy excellent plates. Between the years 1869 and 1873, Colonel Beddome issued his ‘Flora Sylvatica of the Madras Presidency,” illustrated by numerous plates. He also published, between 1869 and 1874, a volume of descriptions and figures of new Indian plants, under the title ‘‘ Icones Plantarum Indize Orientalis.”” Colonel Bed- dome is the only Indian botanist of note, except Griffith, Mr. C. B. Clarke and Mr. C. W. Hope, who has written much on Indian ferns. His two works, the ‘* Ferns of Southern India ” and the ‘‘ Ferns of British India,” published the former in 1863 and the latter between 1865 and 1870, practically give a sys- tematic account, together with excellent figures, of the whole fern flora of India. Of these excellent books a condensation ina popular and abridged form has also been issued. The fourth forest officer who has published contributions to sys- tematic botany is Mr. W. A. Talbot, whose ‘‘ List of the Trees, Shrubs and Woody Climbers of the Bombay Presidency ” gives evidence of much careful research. And the fifthis Mr. J. S. Gamble, who, besides amassing at his own expense probably the largest private collection of plants ever owned in India, has published a systematic account of the Indian Bam- buseae, a tribe of grasses which, from the peculiarity of many of the species in the matter of flowering. had so long been the bane of the Indian agrostologist. Mr. Gamble, in his monograph, gives a description and a life-sized figure of every one of the Indian species. Of this monograph (which forms a volume of the ‘‘ Annals of the Botanic Garden, Calcutta”) Sir Joseph Hooker writes (at p. 375. vol. vii. of his ‘‘ Flora of British India”) ; ‘‘ It is indispensable to the student of the tribe by reason of its descriptions and admirable plates and analyses.” Mr. Gamble has also published a Manual of Indian Timbers. A forest officer who was ever ready to help in botanical work, but who never himself published, was Mr. Gustav Mann, for many years Conservator of Forests in Assam, but now lost to India by his premature retirement. Other forest officers, who have done, and are still doing, good botanical work in their various spheres, are Messrs. Lace, Heinig, Haines, McDonell, Ellis, Oliver, and Upendra Nath Kanjilal. Mr. Bourdillon, conservator of forests in the Travancore State, is also an enthusiastic botanist and collector. In the Madras Presidency botanical work has been carried on during* this second half of the century by Noton, Perrottet, Metz, Hohenacher, Schmidt (on the Nilgiris), Bidie and Law- son. By the efforts of the latter two, a second public herbarium was established in Madras (the first having been broken up many years ago), and in this second Madras herbarium are to be found many of the collections of Wight, besides those of the other Madras botanists just named. In the Bombay Presidency, the only public herbarium is at Poona. This is of recent origin, and owes its existence to the devotion of four men, viz. Dr. Theodore Cooke (late principal of the College of Science at Poona), Mr. Marshall Woodrow (until recently superintendent of the garden at Guneshkind and lecturer in botany in the Poona College), the late Mr. Ranade (a native gentleman), and Dr. Lisboa (a2 medical practitioner in the Deccan)—all four enthusiastic botanists. The amount of Government support given to the herbarium at Poona has hitherto been very inadequate. It is to be hoped that greater liberality may be extended to it now that a stranger to the Bombay Presidency has just been appointed to its charge in the person of Mr. George Gammie, hitherto employed in the cinchona department of Bengal. : Reference has already been made to the botanic gardens at Seharunpore and Calcutta. But to complete this sketch, and especially in order to give a clear idea of the apparatus at present existing in India for carrying on the study and practice of systematic botany, it is necessary again to refer to them. On the retirement of Dr. Jameson in 1872, Mr. J. F. Duthie was selected by the Secretary of State for {India as superintendent of the Seharunpore garden. Mr. Duthie is still at Seharunpore. During his tenure of office he has added to the herbarium pre- viously existing there (which consisted chiefly of the collections of Royle, Falconer and Jameson) a magnificent collection of his own, Mr, Duthie has published a valuable book on the “Field and Garden Crops of the North-western Provinces,” and another on the grasses of the same area. He is now en- NO. 1564, VOL. 60] gaged on the preparation of local floras of the North-west Provinces and of the Punjab. The Calcutta Garden at the date of Sir J. D. Hooker’s arrival in India in 1848 was under the charge of Dr. Falconer, who, in 1855, was succeeded by Dr. J. Thomson, and he in turn by Dr. T. Anderson in 1861. Mr. C. B. Clarke acted as superintendent during the interregnum between Dr. Anderson’s lamented death in 1870 and my own appointment in 1871. The garden and herbarium at Calcutta have been most liberally supported by the Government of Bengal. By funds thus sup- plied the garden has been remodelled and improved ; the herbarium has been housed in an excellent fire-proof building (erected in 1883), and the collections of which it consists have been greatly increased. The chief items of these later acquisi- tions have been the large contributions of Mr. C. B. Clarke ; of Dr. D. Prain, for many years curator of the herbarium, and now superintendent of the garden and of the cinchona plant- ation and factory ; of Mr. G. A. Gammie, formerly one of the staff of the cinchona plantation, and now lecturer on botany in the College of Science at Poona; of Mr. R. Pantling, deputy-superintendent of the cinchona plantation, who, in addition to dried specimens of the orchids of Sikkim, con- tributed nearly five hundred drawings, most of which have been lithographed as the illustrations to a book published in the “* Annals” of the garden, as the ‘‘ Orchid Flora of Sikkim ” ; of Mr. Kunstler, a collector in the Malay Peninsula ; and last, but by no means least, of a trained band of aborigines of Sikkim named Lepchas who possess keener powers of observation of natural objects, more patience, sweeter tempers, and, I am bound in fairness to add, dirtier clothes than any race I have ever met—black, yellow, or white! In addition to their liberal grants to the garden and herbarium, the Bengal Government, twelve years ago, sanctioned the publication, at their expense, as occasion might offer, of monographs of important families or genera of Indian plants. These monographs are printed in quarto, and they are, with one exception, profusely illustrated by plates drawn and lithographed by Bengali draughtsmen. The series is known as ‘‘The Annals of the Royal Botanic Garden, Calcutta,” and it has now reached its eighth volume, the ninth being in active preparation. These ‘‘ Annals” have been contributed to by Dr. Prain (my successor at the Calcutta Garden), by Dr. D. Douglas Cunningham, Mr. J. S. Gamble, Mr. R. Pantling, and myself. About ten years ago, it occurred to the Supreme Government of India that it might be to the interest of science if the four botanical establishments at Calcutta, Seharunpore, Madras, and Poona were to be formed into a kind of hierarchy under the designation of the Botanical Survey of India, without removing either the officers or the four institutions to which they were attached from the financial or general control of the local administrations within which they are respectively situated, the Supreme Government making a small contribution of money for the purpose of exploring little-known districts and making itself responsible for the cost of a publication called ‘‘ The Records of the Botanical Survey.” The four institutions just mentioned continue, therefore, to be paid for and controlled by the Govern- ments of Bengal, the North-west Provinces, Madras and Bombay, but their superintendents are placed on the cadre of the Botanical Survey. The published Records of this Survey now extend to twelve numbers, each of which is devoted to an account of the botany of some part of the enormous and continually expanding area to be explored. Such, then, is the machinery by which systematic, as distin- guished from economic and physiological, botany is carried on within the Indian Empire. But the work done in India itself by no means represents all the work that is being carried on in connection with the elucidation of the flora of the Empire of India. On the contrary, the bulk of the work of elaborating the materials sent from India in the shape of dried specimens has always been, and must always be, done in a large herb- arium ; and until lately no herbarium in Asia has been suffi- ciently extensive. The last word on every difficult taxonomic question must still lie in Europe. A very large number of the herbarium specimens collected in India have found their way to the various centres of botanical activity in Europe, and have been described by botanists of many nationalities. The lion’s share of these specimens has naturally come to the two great national herbaria in the British Museum and at Kew, but especially to the latter. It was inthe Kew Herbarium that Sir Joseph Hooker and his collaborateurs prepared the flora of 606 NATURE British India. And it is in the Kew Herbarium that are to be found the types of an overwhelming proportion of the new species described for the first time in that monumental work, The Kew Herbarium is therefore to the Indian botanist the most important that exists. I must apologise for diverging for a moment to remind you what a type specimen is. It is the very one on which an author has founded any species to which he has given a name. And in order to determine absolutely what is the specific form to which the author meant his name to apply, it is often necessary to examine his type. This necessity increases in urgency with the extension of our knowledge of the flora of the world. The preservation in good condition of a type specimen is therefore, from the point of view of a systematic botanist, as important as is the preservation to the British merchant to the standard pound weight and the standard yard measure on which the operations of British commerce depend. ‘‘ Types” also stand to the systematic botanist much in the same re- lation as the national records do to the national historian. The latter are guarded in the Record Office, I understand, with all the skill which the makers of fire-proof, damp-proof and burglar-proof depositories can suggest. If, however, the type of a species happens to be deposited at Kew, what are the probabilities of its preservation? Such a type at Kew is incor- porated in what is admittted to be in every sense the largest and, forits size, the most accurately named, the most easily con- sulted, and therefore the most valuable herbarium in the world, the destruction of which would be a calamity commensurate in extent with that of the burning of the library at Alexandria. One might therefore reasonably expect that a people who rather resent being called a ‘‘ nation of shopkeepers”? would feel pride in providing for this priceless national collection a home which, although perhaps somewhat inferior to that provided for the national historical records, might at least be safe from fire. This expectation is not fulfilled. The infinitely valuable Kew Herbarium and library have no safer home than an old dwelling- house on Kew Green, to which a cheap additional wing has been built. The floor, galleries and open inner roof of this additional wing are constructed of pine coated with an inflam- mable varnish, and on the floor and galleries are arranged cabinets (also made of pine-wood) in which the specimens (which are mounted on paper) are lodged. The provision of a fireproof building, capable of expansion as the collections ex- tend, is surely not beyond the means of an exchequer which last year netted over one hundred and six millions sterling of revenue. On behalf of the flora of India, I venture to express the hope that the provision of a proper home for its types may receive early and favourable consideration by the holders of the national purse-strings. But India is by no means the only por- tion of the Empire interested in this matter, for the types of the Australasian floras, those of a large part of the North American flora, and those of many species inhabiting countries outside British rule or influence, find their resting-place at Kew. The safe custody of the Kew Herbarium is, therefore, not merely a national, but a cosmopolitan responsibility. In this Address I have hitherto made little reference to crypto- gamic and economic botany. As regards cryptogamic botany there is little to relate. Except Griffith, no Indian botanist of the earlier of the two periods into which I have divided my sketch ever did any serious work amongst non-vascular crypto- gams. During the second period two men have done gallant work under difficulties which no one who has not lived in a tropical country can thoroughly appreciate. I refer to Drs. Arthur Barclay and D, D. Cunningham. The former made some progress in the study of uredinous fungi, which was cut short by his untimely death ; while the latter, in addition to his bac- terial and other researches connected with the causation of human disease, conducted protracted investigations into some diseases of plants of fungal or algal origin. Some of the results of Dr. Cunningham’s labours were published in the Zyansactions of the Linnean Society, and in a series entitled the ‘‘ Scientific Memoirs, by Medical Officers of the Indian Army.’ To the “* Annals of the Botanic Garden, Calcutta,” Dr. Cunningham also contributed elaborate memoirs on the phenomena of nycti- tropism, and on the mode of fertilisation in an Indian species of Ficus (#, Roxburghiz). There is no doubt that, in the past, !yptogamic botany has not been studied in India as it ought to have been and might have been. This discredit will, I hope, soon removed; and I trust that, by the time the twentieth century opens, a cryptogamist may have been appointed to the NO. 1564, VOL. 60] staff of the Calcutta Botanic Garden. The collecting of crypto- gams was not, however, altogether neglected in India in times past. For, from materials sent to England, Mitten was able to elaborate a moss flora of India, while Berkeley and Browne were enabled to prepare their account of the fungi of Ceylon. George Wallich, in whom the botanical genius of his father burnt with a clear though flickering flame, did some excellent work amongst Desmids, and was among the earliest of deep-sea dredgers. Economic botany has, on the other hand, by no means been neglected. It was chiefly on economic grounds that the estab- lishment of a botanic garden at Calcutta was pressed upon the Court of Directors of the East India Company. And almost every one of the workers whose labours I have alluded to has incidentally devoted some attention to the economic aspect of botany. Roxburgh’s ‘‘ Flora Indica” contains all that was known up to his day of the uses of the plants described in it. Much of Wight’s time was spent in improving the races of cotton grown in India. The botanists of the Seharunpore garden during the middle of the century were especially prominent in this branch of botanical activity. Royle wrote largely on cotton and on other fibres, on drugs, and on various vegetable products used, or likely to be of use, in the arts. These botanists introduced into the Himalayas more than fifty years ago the best European fruits. From gardens which owe their origin to Royle, Falconer and Jameson, excel- lent apples grown in Gharwal and Kamaon are to-day purchas- able in Calcutta. Peaches, nectarines, grapes, strawberries, of European origin, are plentiful and cheap all over the North- west Himalaya, and are obtainable also in the submontane dis- tricts. Potatoes, and all the best European vegetables, were introduced long ago ; and at Seharunpore there is still kept up a large vegetable garden from which seeds of most European vegetables are issued for cultivation during the cold season in the gardens of the various regiments of the Queen’s troops quartered in Upper India. More or less attention has been given in the past by Government botanists in India generally to the improvement of the cultivation of flax, hemp, rheea, tobacco, henbane, dandelion, vanilla, sarsaparilla, coffee (Arabian and Liberian), cocoa, ipecacuanha, aloes, jalap, india- rubber, Japanese paper-mulberry, cardamoms, tapioca, coca, tea and cinchona. Only to three economic enterprises, how- ever, have I time to allude in any detail. These are (1) the cultivation of tea, (2) the introduction of cinchona, and (3) the formation of the Forest Department. But before proceeding to the consideration of these I wish to give a short account of the inauguration of the office of Reporter on Economic Products. Up to the year 1883 there had been no special Government de- partment in India for dealing with questions connected with the natural products of the Empire. Whatever had been done prior to that date (and the amount was by no means unimportant) had been the result of isolated and unco- ordinated effort. In 1883 the Government of India founded a department for dealing with the economic products of the Indian Empire, and under the title of Reporter on these products they were fortunate enough to secure Dr. George Watt, a member of the Bengal Educational Service. Dr. Watt is an accomplished and able botanist. He has col- lected Indian plants largely, and has made numerous notes both in the field and in the bazaar. The great work which, on the initiative of Sir Edward Buck, Secretary to the Department of Revenue and Agriculture, and of Sir W. Thiselton-Dyer, of Kew, Dr. Watt began and carried to a successful termination was the compilation of his ‘* Dictionary of Economic Products,” in which valuable book is collected all that is known of almost every Indian product,. whether vegetable, animal or mineral. The study of economic botany is now pursued in India as part of a highly specialised system of inquiry and experiment. Dr. Watt has a competent staff under him in Calcutta, one of whom is Mr. D. Hooper, well known for his original researches into the properties of various Indian drugs. Dr. Watt has arranged in Calcutta a magnificent museum of economic products, and there is no doubt the economic resources of the Empire are now being studied with as much energy as intelligence. ; Tea cultivation is one of the enterprises in the introduction and development of which botanists took a very leading part. The advisability of introducing-the industry was first pressed on the attention of the East India Company by Dr. Govan (of Seharunpore), and in this he was seconded by Sir Joseph Banks as President of the Royal Society. Royle in 1827, and Falconer [OcroBER 19, 1899 | OcroseEr 19, 1899] NATURE 607 slightly later, again urged it as regards the North-west Hima- laya. In 1826 David Scott demonstrated to rather unwilling eyes in Calcutta the fact that real tea grows wild in Assam. In 1835 Wallich, Grifith and McClelland were deputed by Government to visit Assam, to report on the indigenous tea. In the year 1838 the first consignment of Indian-grown tea was offered for sale in London. The consignment consisted of twelve chests containing 20 lbs. each. This first sample of 240 lbs. was favourably reported upon. Last year the exports of tea from India to all countries reached 157 millions of pounds, besides 120 millions of pounds exported from Ceylon ! The introduction of cinchona into India originated purely with the Government botanists. As everybody knows, quinine, and to a less extent the other alkaloids present in cinchona bark, are practically the only remedies for the commonest, and in some of its forms one of the most fatal, of all Indian diseases, viz. malarious fever. The sources of supply of the cinchona barks in their native countries in South America were known to be gradually failing, and the price of quinine had for long been in- creasing. The advisability of growing cinchona in the mountains of British India was therefore pressed upon Government by Dr. Royle in 1835, and he repeated his suggestions in 1847, 1853 and 1856. Dr. Falconer, in his capacity of superintendent of the Botanic Garden, Calcutta, made a similar suggestion in 1852 ; and his successors at Calcutta, Dr. T. Thomson and Dr. T. Anderson, in turn advocated the proposal. In 1858 Govern- ment at last took action, and, as the result of the labours of Sir Clements Markham and Sir W. J. Hooker, of Kew, the medicinal cinchonas were finally, in the period between 1861 and 1865, successfully introduced into British India—on the Nilgiris under Mr. MclIvor, and on the Sikkim-Himalaya under Dr. T. Anderson. Various experiments on the best mode of utilising the alkaloids contained in red cinchona bark resulted in the production in 1870 by Mr. Broughton, quinologist on the Nilgiri plantation, of an amorphous preparation containing all the alkaloids of that bark. This preparation was named Amorphous Quinine. Somewhat later (1875) a similar pre- paration, under the name of Czzchona Febrifuge, was produced at the Sikkim plantation by Mr. C. H. Wood, the quinologist there ; and of these drugs about fifty-one tons have been dis- tributed from the Sikkim plantation up to the end of last year. The preparation of pure quinine from the yellow cinchona barks, so successfully grown in the Sikkim plantation, long remained a serious problem. The manufacture of quinine had hitherto been practically a trade secret. And when the Indian Government had succeeded in providing the raw material from which a cheap quinine might be made for distribution amongst its fever-stricken subjects, the knowledge of the means of extracting this quinine was wanting. Philanthropic platitudes were freely bandied about as to the immensity of the boon which cheap quinine would be to a fever-stricken population numbering so many millions. But there was a singular absence of any practical help in the shape of pro- posals, or even hints, as to how quinine was to be extracted from the rapidly increasing stock of crown and yellow bark. The officers in charge of the cinchona plantations in India had therefore to do their best to solve the problem for themselves. And it was ultimately solved by Mr. C. H. Wood, at one time Government quinologist in Sikkim, who suggested, and Mr. J. A. Gammie, deputy-superintendent of the plantation there, who carried into practice, a method of extraction by the use, as solvents of the cinchona alkaloids, of a mixture of fusel-oil and petroleum. The details of this process were published in the Calcutta Official Gazette, for the benefit of all whom it might concern. Very soon after the introduction of this method of manufacture, the Government factories in Sikkim and _ the Nilgiris were able to supply the whole of the Government hos- pitals and dispensaries in India with all the quinine required in them (some 5000 or 6000 pounds annually), besides providing an almost equal quantity for the supply of Government officers for charitable purposes. The latest development of the quinine enterprise in India has been the organisation of a scheme for the sale at all the post-offices in the province of Bengal, and in some of those of Madras, of packets each containing five grains of pure quinine, that being a sufficient dose for an ordinary case of fever ina native of India. These packets (of which some are on the table for distribution) are sold at one pice each, the pice being a coin which is equal, at the current rate of exchange, to one farthing sterling ! In conclusion, I wish to make a few remarks on the third great NO. 1564, VOL. 60] economic enterprise connected with botany in India, viz. the Forest Department. The necessity for taking some steps to preserve a continuity of supply of timber, bamboos and other products from the jungles which had for generations been exploited in the most reckless fashion, was first recognised by the Government of Bombay, who in 1807 appointed com- missioners to fix the boundaries of and to guard the forests in that Presidency. This scheme was abandoned in 1822, but was resumed in a modified form during 1839-40. Seven years later a regular forest service was established in Bombay, and Dr. Gibson wasits first hea@. Dr. Gibson in turn was succeeded by Mr. Dalzell—and both were botanists. In the Madras Presidency the first man to recognise the necessity of per- petuating the supply of teak for ship-building was Mr. Connolly, collector of Malabar, who in 1843 established a teak plantation at Nelumbur, which has been carried on, and annually added to, down to the present time. In 1847 Dr. Cleghorn (a botanist) was appointed to report on the conservation of the forests of Mysore (which contained the well-known sandal- wood), and the following year Lieutenant Michael (still with us as General Michael, a hale and hearty veteran) was appointed to organise and conserve the public forests in Coimbatore and Cochin. The crowning merit of General Michael’s administration was the establishment, for the first time in India, of a system of pro- tection against the fires which annually used to work such deadly havoc. In 1850 the British Association, at their Edin- burgh meeting, appointed a committee to consider and report upon the probable effects, from an economic and physical point of view, of the destruction of tropical forests. This committee’s report was submitted to the Association at the meeting at Ipswich in 1851. The weighty evidence collected in this report so impressed the Court of Directors of the East Indian Company that, within a few years, regular forest establishments were sanctioned for Madras and British Burma, the two main sources of the supply of teak. In 1856 Mr. (now Sir Dietrich) Brandis was appointed to the care of the forests of the latter province. These forests had been the object of spasmodic efforts in conservancy for many years previously. In 1827 Dr. Wallich reported on the teak forests, and five years later a small conservancy establishment was organised, officered by natives. This, however, was kept up for only three or four years. In 1837 and 1838 Dr. Helfer reported on these forests, and an English conservator was appointed. In 1842 and 1847 codes of forest laws were drawn up, but do not appear to have been enforced to any extent. In 1853 Dr. McClelland was appointed superintendent, but he continued to hold the office for only a short time. A few years after Sir Dietrich Brandis’s assumption of the charge of the Burmese forests, he was appointed Inspector-General of all the Government forests in British India; and it is to him that we owe for the most part the organisation of the Indian Forest Department as it now exists. That organisation includes two schools of forestry (in both of which botany is taught), one in connection with Coopers Hill and the other at Dehra Dun in Upper India. The latter has for many years been under the direction of a gentleman who is distinguished both as a forester and as a botanist. In the Coopers Hill School the higher grades of forest officers receive their training ; at Dehra Dun those of the lower grades receive theirs. The officers of the department on the Imperial list, according to the latest official returns, now number 208, divided into the grades of con- servator, deputy- and assistant-conservator, with a single in- spector-general as chief. In addition to these, there are 566 provincial officers, ranking from rangers upwards to extra deputy-conservators. Botanists took a leading part in moulding the department in its earlier years; for, as already stated, its pioneers—Gibson, Dalzell, Cleghorn, Anderson, Stewart and Brandis—were all botanists. And to most people, who give even casual atten- tion to the matter, it appears fitting that the possession of a knowledge and liking for botany should form a strong charac- teristic of officers whose main duties are to be in the forest. And this belief did for some time exercise considerable influence in the selection of recruits for the department. But, except in the Dehra Dun School, it does not appear to guide the department any longer. For example, at the entrance examination to the Forest School at Coopers Hill, only three subjects are obligatory for a candidate, viz. mathematics, to which 3000 marks are allowed ; German, to which 2000 are allowed; and English, for which 1000 are given. Botany is one of the nine optional 608 NANOT SLE. [OcroseEr 10, 1899 subjects, of which a candidate may take up two, and in each of which 2000 marks may be made. Botany is taught at Coopers Hill, and (according to the Calendar of the College) it forms one of the ‘‘ special auxiliary subjects ” for the forest student. I do not wish to say a single word in depreciation of the botanical teaching at this college, which is probably excellent of its sort. I do not know what value, as part of their professional equipment, students are ac- customed or encouraged to attach to the possession of the means of acquiring a knowledge of the trees and shrubs in the midst of which they are to pass their lives in India. But this I do know, that the ordinary forest officer educated in England now arrives in India without sufficient knowledge to enable him to recognise from their botanical characters the most well-marked Indian trees. To tell such an officer the name of the natural family to which a plant belongs conveys no information to him whatever, for he knows nothing of botanical affinities. More- over, the forest officer after he has arrived in India is not en- couraged to familiarise himself with the contents of the forests under his charge. This will be better appreciated by giving an example than by any number of remarks. Some three years ago, Mr. J. S. Gamble (a forest officer) published a monograph of the bamboos of British India. From bamboos, as you may possibly be aware, a very large amount of forest revenue is annually derived. The sales of bamboos for the year 1896-97 amounted to no less than 110 millions of stems. A great number of the species of bamboos have the curious habit of flowering gregariously at remote intervals of thirty or forty years, and the flowering is followed by death. The absence from the forests for years in succession of flowers of a number of the species, and the similarity of many of them in leaves, had hitherto made members of the group most difficult of identi- fication. Mr. Gamble had devoted himself to their study for many years. Ife had carefully examined all the previously col- lected materials stored in the herbaria at Kew, the British Museum, Calcutta and elsewhere ; and large special collections had been made for him by Mr. Gustav Mann and other officers of the Government. Moreover, he had General Munro’s great paper in the Linnean 7yazsactéons asa basis. Mr. Gamble’s work was undertaken with the full approval of Sir Joseph Hooker, who indeed accepted Mr. Gamble’s account of the bamboos for his ‘‘ Flora of British India.” Mr. Gamble’s monograph is illustrated by a life-sized drawing of each species, wih analyses of the flowers on a larger scale. When com- pleted, the book was published as one of the volumes of the ** Annals of the Calcutta Botanic Garden.” In consideration of the supposed great importance of the book to the forester, and in the belief that the copies would be eagerly taken by the Forest Department, an extra hundred copies were printed, and these hundred copies were put into stout canvas binding suitable for camp use. These copies, or as many of them as he cared to take, were offered to the head of the Forest Department in India at the reduced price of fifteen rupees per copy. The result was an official refusal to buy a single one, although the purchase of the whole hundred (which was not asked for) would have cost only fifteen hundred rupees—a sum which would have reduced the revenue of the year by about one twelve-thousandth part ! An appeal against this ruling having been made to a sul higher authority, a modified order was subsequently issued permitting such forest officers as desired to possess the book to buy copies and charge the cost in their office expenditure. I may state that the book was not a private venture. It was produced at the expense of the Government of Bengal. It is not because I like to play the censor that I have made these remarks about the Forest Department. Having myself served in it from 1869 to 1871, I can speak from my own ex- perience as to the value, from the utilitarian point of view, of a knowledge of the names, affinities and properties of the trees, shrubs and herbs which compose an Indian jungle, and of a knowledge of these as individual members of the vegetable kingdom rather than as masses of tissue to be studied through a microscope. The appointment which I held in India for twenty-six years after leaving the Forest Department gave me full opportunity of getting into touch with all who interest them- selves ina knowledge of plants, and of discovering how few of these at the present day are forest officers. The majority of the atter, if they love their trees, are content to do so without know- ng their names or relationships! There are, of course, splendid exceptions who know as well as love. The general decadence of the teaching of systematic botany in England during the past NO. 1564. VOL. 60] twenty years is, perhaps, to some extent the cause of the low estimation in which the science is held by the authorities of the Indian Forest Department. Twenty-five years ago systematic and morphological botany, no doubt, had too great prominence given to thcm in the teaching at universities and colleges of this country, and the other branches of botanical science were too much neglected, although I do not think they were despised. Nowit appears to me that systematic botany is too much neglected. I hope it is not also despised! Few of the systematists who survive in England are now to be found attached to the univer- sities. They are mostly clustered round the two great herbaria in London ; and such of them as have to look to systematic botany for the means of livelihood are not in the receipt of salaries such as one might reasonably expect in one of the richest countries in the world ! CHEMISTRY AT THE BRITISH ASSOCIA TION. ESPITE the fact that the Dover meeting was a compar- atively small one, the chemists formed a thoroughly repre- sentative gathering, including amongst distinguished foreigners Prof. Lemoine, of Paris; Prof. Fittig, of Strassburg ; and Prof. Ladenburg, of Breslau. The able address of the President, Dr. Horace T. Brown, on the assimilation of carbon by the higher plants, which embodied most valuable and original con- tributions to the knowledge of the complex changes which go on in the living cell, introduced a subject somewhat beyond the usual scope of the proceedings of the Section ; and whilst the chemists present at Dover will always look back upon the address with a special appreciation, they will be equally mind- ful of the many interesting contributions on kindred subjects for which the personality of the President was in the main responsible. Prof. Hanriot, the President of the Chemical Section of the French Association, communicated a short ac- count of the excretory products of plants, in which he dis- cussed the mutations of nitrogen in the vegetable kingdom as based on his own observation of the occurrence of asparagine amongst the secretions of plant roots ; when passed into the soil this product would in all probability become oxidised to nitrates, and thus become directly available for plant life. The experimental confirmation of this view is in course of study. The chemical processes involved in the saccharification of starch by malt- diastase were discussed by Dr. A. Fernbach, of the Institut Pasteur, and by Dr. G. H. Morris. The former detailed his observations on the influence of acids and of some salts on saccharification, which led him to the conclusion that the slightest trace of any free acid retards the action of diastase on gelatinised as well as on soluble starch, provided both the starch and diastase are free from salts on which the added acid may act; but if the solution contains salts, such as secondary phosphates, which are distinctly unfavourable to diastatic action, the addition of acid is favourable as long as there is no excess over the quantity necessary to transform these salts into the primary phosphates. ‘he President regarded these results as opposed to his own observations on the subject, and considered further details of the experiments necessary to justify the con- clusions. Dr. G. H. Morris, in a paper on the combined action of diastase and yeast on starch granules, showed that similarly to the symbiotic action of diastase and yeast on the so-called stable dextrin, ungelatinised intact starch granules, when submitted to the joint action of diastase and yeast, are fermented toa large extent, the maltose first formed being converted into alcohol. The addition of a small quantity of yeast to a cold water malt extract more than doubles the percentage of starch that is changed, and this increased action is not due to any greater activity of the diastase that might result from the removal of the soluble product formed (maltose) from the sphere of action. It appears necessary to have both the diastase and the yeast present together in a condition capable of exercising their respective functions for the increased action to occur. The action of acids on starch was also discussed by Dr. Morris, who showed that maltose is always obtained as a product of hydro- lysis together with dextrin and dextrose; this is in opposition of H. Johnson’s statement that the two latter compounds are the sole products of the action. But the most interesting con- tribution to this branch of chemistry was the joint discussion with Section K (botany) on symbiotic fermentation, on the occasion of the visit of the French Association. The discussion OcToBER 19, 1899] NATURE 609 was opened by Prof. Marshall Ward, who was followed by Sir Henry Roscoe, Prof. Armstrong, M. van Laar, Prof. Reynolds | | read the first report of his committee on the absorption spectra Green, Prof. Warington, M. Tanret, Prof. Francis Darwin and Dr. G. H. Morris. There is little doubt that the dis- cussion has led to a more exact recognition of the division | and relations of symbiotic changes, which should serve to develop the study of the subject. Prof. Marshall Ward, after considering the conditions under which symbiosis exists both in the vegetable and anima] kingdoms, passed to the | more special subject of symbiotic fermentations. Prof. Ward instanced the various grades of symbiotic association that may be recognised, suggesting a special nomenclature, and concluded his remarks with the consideration of the physiology of the subject. The many possibilities that may arise in the mutual life of symbiotic organisms—such as the provision of definite food material by one symbiont for the other, or the ad- vantage derived from a protective influence, or, finally, the exertion of a stimulating action—were discussed, with the con- | | and on isomorphism in benzene sulphonic derivatives. clusion that there is some evidence to support the hypothesis that one symbiont may stimulate another by excreting a body which acts as an exciting drug to the associated organism. The chemical aspect of the subject was concisely treated by Prof. Armstrong, who pointed out that there is an absence of positive evidence to show that one member of a pair of symbiotic | organisms does more than prepare the way for the other by effecting a change which the second is incapable of in- ducing. The possibility of chemical interaction playing a part in symbiotic changes and the hydrolytic function of enzymes were clearly brought out, and illustrations of allied changes of a purely chemical character instanced. Prof. Armstrong pointed out that no case has yet been observed in which a substance is attacked by a pair of organisms neither of which can attack it singly, and regarded it as probable that associated molecules undergo change under the influence of a single organism or agent which determines their association. Prof. van Laar, on the other hand, expressed the view that symbiosis was rather a case of parasitism. Dr. Calmette’s contribution on industrial symbiotic fermentations was read, in his unavoidable absence, by Sir Henry Roscoe. the methods for the conversion of starch into alcohol by the association of pure cultures of moulds with pure yeast cultures, and the industrial application of this symbiotic relation. Both in France and in Belgium thousands of tons of starch are now converted into alcohol by this method, and most favourable results have been obtained both as regards yield and quality. | In inorganic chemistry Prof. Dewar’s important experiments on | the solidification of hydrogen stands foremost; an account of these researches has already appeared in NATURE. Colonel Waterhouse contributed a note on a remarkable result he has observed on the exposure of metallic silver to light ; a visible | image results on the exposed plate after prolonged exposure, but the effect may be recognised in a very much shorter space of time by the development of the latent image produced. An important discussion on the proposal of establishing an International Com- mittee on Atomic Weights was initiated by Prof. F. W. Clarke a critical észemé of both the theoretical and practical aspects of the question. at the Congress of Chemists to be held in Paris next year, Prof. Clarke’s proposal for an International Committee aroused much interest ; but the exact scope of its work appeared difficult to define in the minds of Sir Henry Roscoe, Prof. Fittig, Sir William Crookes and others who participated in the discussion. The desirability of encouraging all capable of undertaking the redetermination of atomic weights was fully recognised, but such work could not be ordered. This view, of course, referred to the theoretical part of the problem ; Prof. Tilden’s suggestion regarding the desirability of an understanding as to the numbers to be chosen for ordinary use was somewhat lost sight of by many of the speakers, especially his important addendum that the values arrived at in atomic weight determinations are obtained under conditions which cannot be observed in daily laboratory practice, and that the adoption, therefore, of numbers regarded as the most exact does not of necessity contribute to | the exactness of ordinary analytical observations, Dr. Glad- stone’s report on the teaching of natural science in elementary schools was followed by an interesting discussion; Dr. Glad- stone, in conjunction with Mr. Hibbert, also contributed a paper dealing with some peculiarities in the drying of colloids such as the hydrates of silica, tin, titanium, iron and alumina. NO. 1564, VOL. 60] | by the Section for their further investigation. | carbon atom acid from glucosone. In this paper an account was given of | Tn view of the proposed discussion of the subject | The papers, reports, and discussions dealing with organic chemistry were of more than usual importance. Prof. Hartley and chemical constitution of organic substances, which, in addition to the work of the committee, contains a valuable summary of that of other investigators. The committee on the action of light upon dyed colours issued their final report, which completes a long series of important experiments carried out chiefly by Prof. Hummel. Prof. Armstrong opened a dis- cussion on laws of substitution, especially in benzenoid com- pounds, in which the conditions of substitution in amines and phenols were dealt with. The course of the reaction in those cases in which ortho- and para-compounds, on the one hand, and essentially meta-compounds, on the other, result were dis- cussed, and the possibility of the formation of intermediate pro- ducts in the former case which subsequently undergo isomeric change fully considered. Prof. Armstrong also contributed papers on the relative orienting power of chlorine and bromine, Ex- tremely interesting isomorphous relations have been observedi amongst these latter compounds, and a committee was appointed, Mr. Fenton read, a summary of his researches on oxidation in presence of iron, in. which the extension of his reaction to tartronic, lactic, glyceric and malic acids was referred to, and, in conjunction with Mr. Jackson, described the condensation products obtained from glycollic aldehyde under the influence of dilute alkali. @-Acrose appears to be formed when a I per cent. solution of caustic soda is used, whilst a starch-like product results when the alde- hyde is heated to 160-170. Messrs. Morrell and Crofts gave an account of further experiments on the action of hydrogen peroxide on carbohydrates in presence of iron salts, the most interesting result obtained being the formation of a dibasic six- Special interest centred in a paper by Mr. W. J. Pope on the influence of solvents on the optical activity of organic compounds, in which he traced the variations in the specific rotation of an optically active sub- stance dissolved in various solvents to the degree of association of the active compound, and on this association factor founded a method for determining whether a particular optically active sub- stance formsa liquid racemic compound with its optical antipode.. Mr. Pope also described a new method for resolving racemic oximes into their optically active components, and Dr. M. O. Forster gave an interesting account of his researches on the influence of substitution on optical activity in the bornylamine series. Dr. Forster also described some new derivatives of camphoroxime, the chief interest of which lies in their relation to certain oxidation products of camphor. Dr. C. A. Kohn and Dr. W. Trantom, in a paper on the action of caustic soda on benzaldehyde, showed that, in the absence of water or in the presence of an excess of aldehyde, benzyl-benzoate is formed as a product of the decomposition; its production points to the formation of an intermediate ortho-compound in the reaction commonly employed in the preparation of benzyl alcohol. Prof. Emerson Reynolds described some new silicon compounds in the form of a letter to Prof. Tilden, who himself contributed | obtained by the action of ethyl mustard oil on silico-phenyl- di-imide, and Prof. Ladenburg read a summary entitled ‘* The development of chemistry in the last fifteen years,” in which the advances of the various branches of the science during that period were dealt with. Of more general interest was a paper | by Prof. Clowes on intermittent bacterial treatment of raw sewage in coke beds, which was followed by one by Mr. W. Scott-Moncrieff on the place of nitrates in the biolysis of sewage. Both papers, as well as the report of the committee on water and sewage examination results, led to an interesting and useful discussion. In a paper on the chemical effect on agricultural soils of the salt-water flood of November 29, 1897, on the East Coast, by Messrs. T. S. Dymond and F. Hughes, | the remarkable result was recorded that although the proportion | of salt left on the soil was insufficient to prove injurious to the growing crops, the earth-worms in the soil were entirely re- moved, with the consequence that very few crops were worth harvesting the following year. This year nine-tenths of the salt originally present has disappeared from the soil, and young worms have again made their appearance, but still the condition of the soil remains unsatisfactory, the rate of percolation of water through the flooded soil being only half as rapid as through the unflooded. This the authors trace to the action of the chlorides of the sea water on the double silicates of the soil with the formation of silicate of alumina in a gelatinous condition, 610 GEOLOGY AT THE BRITISH ASSOCIATION. J\ BANDONING on this occasion the customary procedure of opening the proceedings with the presidential address, Section C plunged at the first meeting into the midst of its work with a long list of papers. The reason for this change was that Sir Archibald Geikie’s address might be heard on Saturday by. the visiting members of the French Association between their reception in the Town Hall and their entertain- ment at luncheon in the College Close. The arrangement proved highly successful, and the President’s eloquent demand that geologists should be allowed to investigate the duration of geological time for themselves with data at their command, unhampered by the vague speculations in which the physicists have indulged, was listened to by a crowded audience, the plat- form being occupied by a distinguished group of British and foreign men of science. As befitted their importance and local interest, the first papers taken on Thursday were those relating to Coal-exploration in Kent. Mr. R. Etheridge dealt at some length with the rela- tions between the Dover and Franco-Belgian Coal-basins, with- out, however, adding much new information to what is already known. Prof. W. Boyd Dawkins, after once more reviewing the history of the discovery, gave some valuable data respecting the boring carried on under his supervision at Ropersole, eight miles north-west of Dover, where Coal-measures have been struck at a depth of 1580 feet, after Chalk, Gault, Lower Green- sand, Wealden, Corallian, Oxfordian, Bithonian and Liassic strata had been passed through, and respecting other borings at Ottinge, Hothfield, Old Soar near Tonbridge and Penshurst, of which the first, at a depth of 730 feet, is in Kimeridge Clay ; the second, at 800 feet, in Portlandian beds; the third, at over 700 feet, in Hastings Sands; and the last, at 1867 feet, in Kim- eridge Clay. From these data, Prof. Dawkins concludes that the southern boundary of the concealed coal-basin ranges under the southern scarp of the North Downs for some distance to the westward of Dover, along the line marked by the Pembroke- Mendip anticline, and that to the south of this anticline the Paleozoic floor is probably composed of pre-Coal-Measure rocks. The discussion elicited by these two papers was scarcely worthy of the subject, perhaps from the matter having lost its freshness through so much having been written upon it. At the same meeting Mr. W. Gibson, of H.M. Geological Survey, contributed a short account of the results of his investi- gations among the Upper Carboniferous rocks of North Stafford- shire, which have an important bearing upon the question of the coal-fields lying concealed beneath the Red Rocks of the Midland counties. Mr. Gibson showed that considerable areas of so- called Permian rocks in the region which he has examined are conformable to the Upper Carboniferous strata and cannot be separated from them. By working out the details of these strata he has been able to detect true Upper Coal-Measures farther westward than has hitherto been done, and has found evidence that on the north-west side of the North Staffordshire anticline the valuable coal-measures and ironstones do not un- interruptedly descend beneath the so-called Permian, but rise locally westward and are nearer the surface than might have been expected. Another paper of stratigraphical interest was that of Mr. A. J. Jukes-Browne on a recent boring through the Chalk and Gault near Dieppe, which shows that the Folkestone and Wissant facies of the Gault extend southward as far as Dieppe, a distance of about fifty-two miles, Owing to the lantern being available on two days only during the meeting, viz. on Friday and Monday, it became necessary to take all papers requiring this method of illustration on these days, and the usual grouping of the contributions according to subject was, in consequence, only partially possible. At Friday's session Dr. A. W. Rowe gave an account of the methods by which he has attained such magnificent results in the photo- micrography of opaque objects, illustrating his address by a representative series of views to demonstrate the value of this mode of research in the study of the minute structure of fossils. Dr. G. Abbott then discussed the formation of concretions ; and Dr. H. J. Johnston-Lavis dealt with that thorny question the origin of oolitic structure, renewing the debate begun last year at Bristol and strongly combating Mr. Wethered’s view that the structure was originally organic. Unfortunately, Mr. Wethered Was not present to sustain his case, but there was nevertheless NO. 1564, VOL. 60] NALORE [OcroBER 19, 1899 an instructive discussion. Prof. W. J. Sollas in a short note on a cognate subject, the origin of flint, stated that he had recently found the hollow casts of sponge-spicules in abundance in the chalk in the vicinity of bands of flint both in Oxfordshire and on the Kentish coast, thus sustaining the view that the silica of the nodules was derived from this source. Mr. E. Greenly described at this session some remarkable funnel-shaped pipes of hard sandstone in the Carboniferous Limestone of Dwlbau Point, East Anglesey, due to contem- poraneous erosion of an exceptional kind ; and he also gave an account of the glacial phenomena of the same locality. Prof. P. F. Kendall had an excellent paper on extra-morainic drainage in Yorkshire, in which he claimed that numerous abnormal valleys in the Eastern Moorlands and in the hills west of the Vale of York must have been excavated by the drainage of lakes formed at the margin of the ice-sheet during the glacial period ; and Mr. J. Lomas put forward some. new ideas respect- ing the formation of lateral moraines and rock-trains in glaciers. On Saturday, as already mentioned, the president delivered his address, which constituted the only business of the Section. On Monday a long list of papers was taken, including several with lantern illustration. Prof. Sollas discussed Homotaxy and Contemporaneity, showing that Huxley’s well-known contention could not be sustained and had led to much misunderstanding of the value of fossil evidence. Prof. W. W. Watts briefly described a smoothed and grooved surface of Mount Sorrel Granite underlying undisturbed Keuper Marl, and his paper led to one of the best discussions of the meeting as to the climatal conditions of Triassic times, most of the speakers agreeing that the surface in question had probably been worn by wind-driven sand, and that it afforded further evidence of desert conditions during the period. Another short paper of high importance was that of Prof. A. Renard on the origin of Chondritic Meteorites, in which it was shown that the rock-structure of certain of these extra-terrestrial fragments presented the familiar phenomena of dynamo-metamorphism. As the president remarked in the discussion, it is not often that the geologist can apply the principles of his science beyond the sphere he inhabits. The local effects of coast-erosion were next described and well illustrated by Captain McDakin and Mr. G. Dowker, after which Mr. W. Whitaker presented the first fruits of the efforts recently made by the Council of the Association to obtain from the coastguards all round our shores, with the sanction of the Lords of the Admiralty, schedules of information as to the changes due to the action of the sea. Mr. Vaughan Cornish then exhibited a series of photographs of Wave-phenomena, and discussed the relations between wave- forms in different substances, a discussion which was renewed at a later session. * The eruption of Vesuvius in 1898 was described and illustrated by Dr. Tempest Anderson ; while Prof. G. Platania contributed an account of the recent volcanic phenomena of Mount Etna; and an excellent day’s work was concluded by a report by Prof. P. F. Kendall on the results obtained by a local committee, by the use of chemical reagents, as to the flow of underground waters in the limestone district of Craven in Yorkshire at the sources of the Aire. A committee of the Association was formed to continue these researches, and a grant of 50/. was obtained in aid of the expenses. The first paper taken on Tuesday was that of Prof. W. Boyd Dawkins on the geology of the Channel Tunnel, in which, after indicating the conditions under which the proposed tunnel would have been made, it was stated that in the portion 2300 yards long already excavated on the English side, the Lower Grey Chalk was soft enough to be easily cut by machine and hard enough to stand without lining, and that five years’ exposure had not sensibly affected its cut surface. It was generally conceded by the speakers in the subsequent discussion that the geological conditions were peculiarly favourable for the construction of the tunnel, and that, apart from the political question, no insuperable difficulty was likely to be encountered. Mr. F. W. Harmer then read a carefully prepared paper on a proposed new classification of the Pliocene deposits of the east of England, in which he suggested the terms Lenhaman for the Lenham Beds, Gedgrvavian for the Coralline Crag, Wadtontan, Newhournian and Butleyan for different portions of the Red Crag, Zcentan for the Norwich Crag, and Cfzllesfordean and Weybournian respectively for the Chillesford and Weybourne deposits. The author considers the Red Crag to have accumu- lated in shallow inlets which were silted up one after another during a slow upheaval of the southern part of the area. Ina OcToBER 19, 1899] WA TORE 611 second paper Mr. Harmer discussed the meteorological con- ditions of North-western Europe during the Pliocene and Glacial periods, finding in the early glaciation of Scandinavia, and the consequent establishment of anticyclonic conditions over that area, a probable solution of the change in the direction of the prevalent winds which he believes to be necessary to account for the accumulation of the crag-deposits on our eastern coast. A short paper by Rev. J. M. Mello on some palzolithic imple- ments of North Kent, and the exhibition on behalf of Mr. B. Harrison of a collection of ‘‘eoliths” from the neighbourhood of Ightham, led to a brisk discussion, in which Sir John Evans, Prof. Boyd Dawkins and other speakers denied that the so- called ‘‘eolithic implements ” showed proof of human workman- ship, while Prof. T. Rupert Jones stated Mr. Harrison’s view of the case and was supported by Mr. Allen Brown. The chief paper of the final session on Wednesday was that of Mrs. M. M. (Ogilvie) Gordon on sigmoidal curves in the earth’s crust. This admirably rendered discourse was supple- mentary to the work recently published by Mrs. Gordon in the Quarterly Journal of the Geological Soctety and in NATURE, _ and had for its object the general statement of the phenomena which are presented when rock-folds in two directions intersect each other and produce “‘ crust-torsion,” with particular reference to the earth-forms which have been thus produced in the Alpine mountain-system. The complexity of the subject seemed to daunt most of the speakers in the discussion ; but Prof. Lapworth pointed out how well the results of Mrs. Gordon’s field-work agreed with the theoretical deductions to be drawn from the study of intercrossing earth-waves. As usual, some of the most solid work of the Section was embodied in the reports of the committees of research which were presented during the meeting, but of which lack of space forbids more than the bare mention. Among these were the reports presented by Prof. A. P. Coleman on Interglacial Beds in Canada; by Mr. P. M. C. Kermode on the Deposits con- taining Elk remains in the Isle of Man; by Prof. P. F. Kendall on Erratic Blocks; by Rev. G. C. H. Pollen onthe Ty Newydd Caves; by Mr. H. Bolton on the Uphill Caves ; and by Prof. W. W. Watts on Geological Photographs. Short afternoon excursions, which have become an established feature of the Section’s arrangements, were made during the week to the Ropersole Coal Boring, to the colliery works under Shakespeare Cliff, to the East Cliff and St. Margaret Bay, and to the Warren at Folkestone. To sum up the proceedings of the week—the sessions of the Section were well attended throughout, and the papers, though without any especially salient features, maintained a good average both in numbers and quality. Some paleontological papers which might have found place in the Section were taken in Sections D and K, and this branch of geological science was in consequence scantily represented in the list. UNIVERSITY AND EDUCATIONAL INTELLIGENCE. CAMBRIDGE.—Mr. W, L. H. Duckworth has been appointed to the University lectureship in physical anthropology. Mr. R. G. K. Lempfert has been appointed Assistant Demonstrator in Experimental Physics. It is proposed that McGill University, Montreal, be adopted as an institution affiliated to the University. A NEw technical institute is to be erected, at a cost of 8450/., in Carisbrooke Road, Liverpool. THE sum of 25,000 dollars has been promised to Vassar College towards a biological laboratory on condition that an equal amount be raised for the same purpose by other means. THE foundation-stone of a new technical college for Sunder- land has just been laid. The college is to cost 25,000/,, and will, it is hoped, eventually be affiliated to Durham University. Dr. C. B. Davenrort, of Harvard University, has been appointed professor of zoology at the University of Chicago, in the place of Prof. Wheeler, who has gone to the University of Texas. Mr. H. B. KNow Les has been appointed principal of the Swindon and North Wilts Technical School. Hitherto he has been teacher of physics and electrical engineering at the Bradford Technical School. NO. 1564, VOL. 60] THE Technical Instruction Committee of the West Riding (Yorks.) County Council have consented to financially assist the managers of the district technical schools in forming reference libraries on the subjects of local instruction. Mr. Emerson E. McCMILiin has given the Ohio Academy of Science 250 dollars with which to carry on scientific in- vestigations, and declared his intention of giving a similar amount annually if the money is wisely expended. DarrmMoutH (U.S.A.) COLLEGE has recently received from Mr. E. Tuck, of New York, 300,000 dollars, to be used for the purposes of instruction, and Tuft’s College has had bequeathed to it the sum of 60,000 dollars by the late Mrs. M. D. Goddard, of Newton, Mass. THE regents of the University of California have accepted the plans designed by M. Bénard, of Paris, for their new university buildings, and some of the buildings will, it is stated, be begun next spring. The movement, as will be remembered, is mainly due to the generosity of Mrs. Phcebe A. Hearst. AT a meeting held at Newcastle on Monday last, it was decided to make an effort to raise funds for the completion of the buildings in connection with the Durham University College of Science. Subscriptions amounting to 9500/. were promised at the meeting, and the sum of 100,000/. will, it is hoped, be raised by the end of the year. IN connection with the Liverpool University College, Mr. W. Rathbone has made provision for the award annually of a Rath- bone medal to the most distinguished third-year student. Mrs. George Holt and Miss Emma Holt (to whom the College has on more than one former occasion been much indebted) have each given the sum of 5000/, towards the physical laboratories of the institution. AMONG recent appointments abroad we notice the following :— Dr. S. Avery to be professor of chemistry in the University of Idaho; Mr. H. B. Ward to be professor of zoology at Nebraska University ; Mr. P. Field to be professor of mathematics in Carthage College; Dr. E. O. Sisson to be director of the histological laboratory in the recently consolidated medical schools of Keoduk, Iowa. WITH reference to a recent note in this column respecting the admission of women students to the course of study at the Owens College which would qualify them for medical degrees and practice, we are requested to state that the resolution in favour of the course adopted was carried by a majority of nine- teen, the voting being twenty-one for the resolution and two against it. THE promoters of the Birmingham University scheme have recently received the munificent donation of 20,000/. from Mr. Charles Holcroft, and a number of large sums from other gentlemen, which bring the total amount promised to upwards of 315,400/, The total of over 300,000/. having been reached, the committee have secured the last 12,500/, which was offered by the friend of Mr. Joseph Chamberlain who prefers to remain anonymous, SCIENTIFIC SERIAL. American Journal of Science, October.—Explosive effect o1 electrical discharges, by J. Trowbridge, T. C. McKay, and J. C. Howe. The authors investigated the sudden increase of pressure in the gas, through which the discharge passes, by means of a vacuum tube provided with a manometer gauge. When spark-gaps up to 50cm. were employed, with a maximum difference of potential of three million volts, they found that the explosive effect increased closely in proportion to the length of the spark, and began to diminish when the spark was longer than 50cm. The air itself then becomes a fairly good con- ductor, and is strongly ionised.—Colour vision and the flicker photometer, by O. N. Rood. The author’s flicker photometer reveals the fact that the curve of colour vision is not the same in any two persons supposed to have normal sight: Among five persons capable of sustaining Holmgren’s worsted test, differ- ences of colour values ranging from I to 14 per cent. were found.—Iodometric determination of gold, by F. A. Gooch and I. H. Morley. The authors investigate the effect upon the immediate evolution of iodine brought about by adding varying amounts of water to the gold solution before introducing the 612 NATURE i [OcToBER 19, 1899 iodide, and the effect of different amounts of iodide at different dilutions. —Mineralogical structure and chemical composition of the Trap of Rocky Hill, N.J., by A. FH. Phillips. The Rocky Hill trap, from its holocrystalline nature, would be classed as a dolerite. From the character of the decomposition of the olivine, and the solution cavities in the diallage crystals, the intrusive nature of this dike is evident, as it must have been formed at a considerable depth below the surface and under very heavy pressure.—Some analyses of Italian volcanic rocks, by H. S. Washington. This paper deals with the composition of trachytes of the Phlegrean Fields and of Ischia. There are three parallel volcanic lines in the Italian district. The latest, along the peninsula, is characterised chiefly by high K,O, by high CaO, and the presence of leucite. The next, that of the islands along the west coast, is high in alkalis, but with Na,O rather higher than K,O, and without leucite. The third, which lies far out in the Mediterranean, and which is possibly the oldest, is much higher in soda, and seems to be characterised by the presence of peculiar soda minerals such as enigmatite and eginine, nepheline also occurring in places. —Thermo-electricity in certain metals, by L. Holborn and A. L. Day. This is an English version of the author’s Reichsanstalt paper on the gas thermometer. SOCIETIES AND ACADEMIES. Paris. Academy of Sciences, October 9.—M. van Tieghem in the chair.—On the elastic equilibrium of a rectangular plate, by M. Maurice Lévy.—Some remarks on double integrals of the second species in the theory of algebraic surfaces, by M. Emile Picard. —On a modification of Bessel’s method for calcu- lating occultations, by M. L. Cruls. In the modification sug- gested use is made of the time of apparent conjunction of the two stars. The advantage resulting from this method is two- fold: it gives by a single calculation a precision generally only obtainable by a second approximation, and lends itself easily to a graphical construction and a simple geometrical interpretation of the different elements upon which the conditions of the phenomenon depend.—Observations of the Giacobini Comet (1889 e) made at the Observatory of Besancon, by M. P. Chofardet. The observations were made on the nights of October 3 and 4. The comet had the appearance of a nebulous ‘sphere, 1’ in diameter, and having a slight nucleus of about the 13th magnitude.—On fundamental functions and on the de- velopment of a holomorphic function at the interior of a contour in a series of fundamental functions, by M. Renaux.—On the stereochemistry of nitrogen, by M. J. A. Le Bel. The author replies to various criticisms by van’t Hoff, Markwald and others on his work published in 1891 on the preparation of active com- pounds from methyl- ethyl- propyl-isobutylammonium chloride, and lays down the exact experimental conditions necessary to repeat his results. The conclusion is drawn that there can now be no doubt as to the optical isomerism existing in the derivatives of ammonium chloride containing four different radicles, and containing at least ten atoms of carbon. It is also established that with derivatives less rich in carbon the stability of these optical isomerides is diminished.—On the reversible liquefaction of albuminoids, by M. Tsvett. It is known that the solution of albuminoids is favoured by certain acids, alkalis, and salts. The author has found that certain organic substances, such as resorcinol, pyrocatechol, phenol, chloral hydrate, &c., possess this liquefying property to a very marked extent. Thus a solution of gelatine treated with an eighty per cent. aqueous solution of resorcinol, forms two liquid layers, the upper a solution of gelatine in aqueous resorcinol, the lower a solution of aqueous resorcinol in gelatine, the co- efficients of reciprocal solubility varying with the concentra- tion of the resorcinol and the temperature. The phenomenon appears to be truly reversible.—On the volumetric estimation of quinones derived from benzene, by M. Amand Valeur. The quinones are reduced by a mixture of potassium iodide and hydrochloric acid, and the liberated iodine titrated with sodium thiosulphate. Experiments were carried out with quinone, dichloroquinone, toluquinone, and thymoquinone ; the results are quite satisfactory, and are very rapidly obtained,— On the structure of the nucleus in the myelocytes of Gasteropods and Annelids, by M. Joannes Chatin. The myelocytes of these invertebrates, contrary to the usual statements, may show a very NO. 1564, VOL. 60] clear, nuclear membrane.—On the alternation of generations in Cutlerta, by M. C. Sauvageau.x—On a gutta-percha plant capable of being cultivated in a temperate climate, by MM. Dybowski and G. Fron. The authors have extracted gutta- percha from the fresh leaves of Hucomza ulmoides. This plant can be grown in temperate climates, and ~ experiments were carried out as to the best mode of multiplication of the plant. It is easy to obtain good seeds in large quantity, but their ger- mination is difficult and capricious. Propagation through cuttings, however, offers no difficulties, the slips taking root easily and developing vigorously.—Action of anzesthetic vapours upon the vitality of dry and moist seeds, by M. Henri Coupin. The vitality of dry seeds is unaffected even by saturated ether and chloroform vapours ; but with moist seeds the case is quite different, the presence of only 377 c.c. of ether in 10 litres of air being sufficient to kill the seed. DIARY OF SOCIETIES. THURSDAY, Ocroser 19. Camera C ius, at 8.15.—Clouds and Photographic Landscapes: J. Cadett. TUESDAY, OctToBeER 24. Royal PHOTOGRAPHIC SOCIETY, at 8.—Wellington Film: Harry Wade FRIDAY, OctoBeER 27 PuysicaL SOCIETY, at 5.—The Magnetic Properties of the Alloys of Iron and Aluminium: Dr. S. W. Richardson.—Exhibition of a Model illus- trating a Number of the Actions in the Flow of an Electric Current : G. L. Addenbrooke.— Repetition of some Experiments with the Wehnelt Interrupter devised by Prof. Lecher: W. Watson INSTITUTION OF MECHANICAL ENGINEERS, at 7.30.—The Incrustation of Pipes at Torquay Water Works: William Ingham.—A Continuous Mean-Pressure Indicator for Steam Engines: Prof. William Ripper. CONTENTS. PAGE Electro-magnetic Theory. By C.S. Whitehead . 589 Our Book Shelf :— Robson: ‘* Catalogue of the Lepidoptera of North- umberland, Durham, and Newcastle-upon-Tyne. °— 1 Oe | a cio) SEO “© The Process Year-Book for 1899”. . .« : coe Boe Wrapson and Gee: ‘‘ Mathematical Tables” . 590 Maupin : ‘‘ Opinions et Curiosités touchant la Mathe- matique ” SIGS 590 Letters to the Editor :-— Peripatus in the Malay Peninsula.—Prof. Edward BB: Poulton RiSteaememeise sy! * 591 Dark Lightning Flashes.— Shelford Bidwell, F.R.S. . cg lee <0) : 3 . 591 Heredity and Variation. —Prof. J. Mark Baldwin 591 Phosphorescent Earthworms.—Prof. W. Blaxland Benham) 20. - eens. = Ge . 591 Meeting of the International Meteorological Com- mittee) . ... <) ai-05) Sameer . 2) ES OFT The Coming Shower of Leonids. (Wzth Diagram.) By W. F. Denning . 592 Notes MEPL MG Go % < 594 Our Astronomical Column :— Comet Giacobinil(t899\e) Meee ;| - a 597 Holmes’ Comet (1899d@) .... 597 Opposition of Jupiter, 1899 ........ 597 Law Connecting Motions in Planetary System 597 On the Characteristics of a University. By Prof Rucker, F.R.S. 5): 10 Ree « 598 Forthcoming Books of Science 601 The British Association :— Section K.—Botany.—Opening Address by Sir George King, K.C.I.E., F.R.S., President of the’Section.. I) 2yageeens b 24 604! Chemistry at the British Association 608 Geology at the British Association 610 University and Educational Intelligence POLE Scientific Serial ... ee Ol Societies and Academies . 612 Dianyol societies 2 meee 612 Mead URE 613 THURSDAY, OCTOBER 26, 1899. THE INTERNATIONAL ASSOCIATION OF ACADEMIES. F late there has been much activity in matters which require the co-operation of scientific men of different nationalities. The International Catalogue of Scientific Literature has been the subject of several con- ferences. The International Meteorological Conference and the Bureau International des Poids et Mésures are samples of different types of organisations which are both numerous and useful. The exchange of courtesies at Dover between the British and French Associations for the Advancement of Science gave another proof that cosmopolitanism is grow- ing in strength in the scientific world, and can assert itself even when the political atmosphere is not unclouded. __ A still more striking instance of the same fact will be found in the account which we give in another column of a conference at which the possibility of founding an International Association of the great Academies of the world was discussed by their representatives. The details of the plan are, we believe, still under con- sideration, but enough has been done to make it practically certain that the Association will be founded, and that the Royal Society, the Academies of Science of France, of Berlin, St. Petersburg, Vienna, Rome, Washington and other similar bodies will be brought into formal relations with each other. It is, no doubt, open to pessimists to say that international meetings are now too numerous, but we venture to think that the proposal to bring about formal conferences between the principal scientific bodies in the world is most important, and that the meet- ings are likely to lead to more permanent results than do gatherings (also useful in their way) from which the picnic element is not altogether eliminated. On the other hand, an Association of Academies will bea more flexible instrument for good than are inter- national organisations appointed for specific purposes, and composed either of persons named by the Governments of the countries represented, or of officials controlling national observatories. The Committee of the Bureau International des Poids et Mésures in Paris and the Geodetic Conference at Berlin are examples of bodies which are entrusted with strictly defined duties, and cannot travel outside the lines laid down for them by their respective Govern- ments. A union of Academies would, however, bring about the meeting at stated intervals of representatives of science, who would not be fettered by the official ties which must necessarily restrict the action of Govern- ment nominees. It would thus be possible for the associated Academies to discuss questions connected with any branch of science which might in their opinion call for international co-operation, and if they decided that such action was. desirable, to take steps to call the attention of the scientific world or of the various Govern- ments to the necessity for united action. The Association would, in fact, enjoy the same | freedom as the Council of the Royal Society, while it * would be able to bring to bear on any question the | NO. 1565, VOL. 60] | Edward. mature opinion of representatives of the whole scientific world. It is obvious that an Institution founded on these lines may become of the very first importance, and may play the part of an international parliament of science. Whether or no such a hopeful forecast is realised, it cannot but be useful that the centres of scientific organ- isation in different countries should themselves be organ- ised, and should be united—not merely by common interests, or by the bonds of friendship which have been established between many of their members—but by formal links which will enable them to take united action when such action is required. As some of the foreign Academies are concerned with literature and philosophy as well as with natural science the Association will be based upon the same lines. The two sections into which it will be divided will, however, be almost entirely independent, and no serious difficulty need be anticipated on this score. It is, however, curious that though both of the great Anglo-Saxon nations pos- sess important societies concerned with the cultivation of different branches of literature, history or philosophy, neither of them has developed an institution the breadth of whose aims would warrant its inclusion in a list of Academies of literature. It will be unfortunate if this fact makes the literary section of the new Association less truly representative than that which will be concerned with natural science. “An academy quite like the French Academy .. . we shall hardly have, and perhaps we ought not to wish to have it,” said Matthew Arnold, but it will be interest- ing to see if the foundation of an International Associa- tion of Academies leads to a rearrangement of existing organisations which might give us in England something corresponding to the ‘‘Académie des Inscriptions et Belles-Lettres,” or to the ‘Académie des Sciences Morales et Politiques.” A PIONEER IN TELEGRAPHY. The Life Story of the late Sir Charles Tilston Bright; with which ts incorporated the Story of the Atlantic Cable and the First Telegraph to India and the Colonies. By his Brother, Edward Brailsford Bright, and his Son, Charles Bright. Pp. xix + 506, and xi + 701. (Westminster: A. Constable and Co.) WO books have recently appeared dealing with tele- graphy from shore to shore, the one on ‘‘ Submarine Telegraphs” from the pen of Mr. Charles Bright alone, the other the two-volume treatise now under review. Both are somewhat lengthy, the former because the de- scription of “ Submarine Telegraphs” was so much bound up with details concerning the life of Sir Charles Bright, and the latter because to the ‘“‘ Life Story of the late Sir Charles Bright” has been added so much about the history of submarine telegraphy. Leaving the accounts of the ancestors of this family which are given in rather bewildering detail, we come to the boyhood and youth of the two brothers Charles and Charles at fifteen, and Edward at sixteen, entered the service of the Electric Telegraph Company soon after its formation in 1847, and started on their careers as inventors. In 1849 they devised a method DD 614 for enabling the position of a fault on a telegraph line to be ascertained electrically by the use of resistance coils. In two more years they both left the Electric Telegraph Company, and joined other companies which had started as rivals of this company and of one another, viz. the British Telegraph Company, to which Charles became the assistant engineer, and the Magnetic Telegraph Company, with which Edward associated himself. But it was the ingenuity and energy which the subject of this memoir displayed in laying the telegraph wires under the streets of Manchester that first brought him into prominent notice. In one night the many gangs of navvies under his superintendence had the streets up, the lower halves of cast iron tubes laid down, gutta-percha covered telegraph wires (wrapped into ropes with tarred yarn) unwound off drums into this iron channel, the two halves of the tubes placed in position, the trench filled up, and the pavement laid down before the inhabitants were out of their beds in the morning. This account reads like that of a cutting-out expedition of a young Nelson, or a surprise attack of a youthful Wellington, and such an exploit hardly seems possible in the case of the County Council scholar of the modern day, full, it is true, of facts and knowledge, but who has devoted so much attention to learning off what other people have thought out, that he has never had time to find out what he thinks himself, and the bent of whose activity seems to be directed to begging his numerous teachers to give him a sheaf of testimonials and to furnish him with a post. We can also recommend the study of this exploit of the nineteen-year old Bright to the notice of the local authorities of London from another point of view. In entire oblivion apparently of the fact that the traffic in our streets is not only as great as it was half a century ago, but has become one of the most perplexing diffi- culties of the present time, and probably in ignorance also of the fact that the developments that have taken place during the past ten years in electric lighting have supplied facilities for carrying on night work in the streets such as were not dreamt of fifty years ago, Bumble still lays long lines of pipes under Fleet Street, Holborn, and the Strand, on what may be called the one man, one boy and a donkey-cart method. And further, since it is generally during the height of the London season that the streets remain broken up for days at a time, we presume that the local authorities are labouring under some delusion that the navvy periodically spends his autumn away from town—say in Switzerland— and is, therefore, only available as an obstructionist about the month of May. The cable to Ireland having been successfully laid in 1853, attention began to be turned to connecting Great Britain with America. The Atlantic Telegraph Com- pany was consequently formed, but without advertise- ments or a board of directors, without brokers, com- missions, executive officers, promotion money, or even a prospectus. What a striking contrast to the present philanthropic efforts of the “vendor” to benefit the world, and the anxiety of the “scientific expert” to give wide publicity to the extraordinary efficiency of every- thing that is brought to his notice—professionally. NO. 1565, VOL. 60] NATURE [OcToBER 26, 1899 Considerable vagueness existed at that period as to what the speed of sending messages through a submarine cable really depended on; the memoir states that Sir Charles Bright advocated the employment of a thick copper conductor, weighing 34 cwt: per mile, surrounded by a coating of gutta-percha having the same weight, but that Faraday, Morse and Whitehouse did not under- stand the problem properly, and therefore that they opposed Bright’s proposal to use a large conductor for the reason that the electric capacity of the cable would be thereby made large, and as, therefore, a large amount of electricity would be required to charge it at each signal the speed would be slow. Lord Kelvin in his Royal Society paper pointed out that the retardation depended neither on the capacity alone nor on the resistance of the conductor alone, but on the product of the two ; and so made the whole theory clear—at least made it clear to those who were able to appreciate what a Fourier series could possibly have to do with telegraph- ing to America. But economical counsels prevailed, and the copper conductor of the actual Atlantic cable weighed only 107 Ibs. a mile, and the gutta-percha coating 261. The account of the laying of the first Atlantic cable is stirring, thanks partly to the long extracts from the graphic and exciting descriptions which were published by Mr. Nicholas Woods in the Zz7zes. Numerous were the attempts to lay this cable, and, although they were at last crowned with success—in so far that an Atlantic cable was completed in August 1858, and several messages were actually sent through it—this cable had but a very brief life, one of only three short months in fact. Numerous arguments are adduced to prove that the causes which led to its break-down all arose from one reason, viz. that the directors did not take the advice of Sir Charles Bright. But, although it is undoubtedly true that the subject of the memoir was an exceptionally able, enthusiastic and energetic man, the contention that if only his advice had been followed the 1858 Atlantic cable would have been a permanent success is not quite so obvious. For example the use of a powerful induction coil to work a long cable, which is so properly denounced in the body of the book itself, and to which the speedy death of the first Atlantic cable was undoubtedly, at any rate in part, due, was actually resorted to by Sir Charles in his experiments on ten separate lengths of underground wire, joined up to make a total length of two thousand miles, as described in his remarks at the Institution of Civil Engineers in 1857, and quoted in Appendix v. of the book under review. And the successful results obtained with these induction coils “thirty-six inches in length and excited by a powerful Grove battery of fifty pint cells,” were advanced as a reason why “he could not see what there was to prevent the working, successfully, through a direct line of two thousand miles” such as an Atlantic cable. Again, the folly of the Atlantic Telegraph Company in not adopting the larger dimensions which Sir Charles Bright desired to give to the first Atlantic cable is not so evident, since the 1865 cable, which possessed these dimensions, had to be abandoned—broken, after many OcTOoBER 26, 1899] unsuccessful attempts had been made to lay it—and in the following year, some months after it had been re- covered and completed, both it and the new 1866 cable broke, while one of them broke again the following year. The fact is that to construct an Atlantic cable at all in NATURE those days was a very courageous thing to do; to lay it | successfully, even with many failures, evinced a faith and confidence in engineering skill and a dogged spirit | of determination that make one proud of the Anglo- Saxon race. To every one who took a prominent part in the enterprise, as certainly did Sir Charles Bright, all honour is due as well as the thanks, not only of his contemporaries, but of all who have followed him. But we are inclined to think that the authors of this memoir would have been well advised had they not allowed their reverential memory for the brother of the one and the father of the other to lead them to adopt the painter’s only method of representing a bright light, viz. by intentionally throwing the rest of the picture into shade. Volume ii. deals with the telegraph to India, Sir Charles’ parliamentary life, the West Indian cables, Sir Charles’ work in connection with mining, fire alarms, telephony, electric lighting, the Paris Electrical Exhi- bition of 1881, the Institution of Electrical Engineers, Freemasonry, and concludes with various appendices. This life-story is distinctly interesting, but its interest would have been even greater had the matter been com- pressed into about half, or at any rate into not more than two-thirds, the space. Before a second edition appears we would suggest that such scientific crudities as the fol- lowing should be altered :—‘‘ A current which was esti- mated by the experts to amount to about 2000 volts.” “In the absence of a determinate unit of inductive capacity or quantity of electricity condensers were em- ployed for the first time.” ‘When electricity passes through this surrounding coil of wire, the magnet and mirror take up a position of equilibrium between the elastic force of the silk and the deflecting force of the current. . . . The magnet is artificially brought back to zero with great precision after each signal by the use of an adjustable controlling magnet.” OUR BOOK SHELF. The Maintenance of Solar Energy. By F.R.A.S. Pp. 20. (London: The Southern Publishing Co., Ltd., 1899.) THE author of this short essay is not satisfied with the current ideas as to the maintenance of solar energy, but believes his new views tend to remove much of the difficulty. So far as can be judged by these “pre- liminary notes,” however, the theory advanced is one which is not likely to convince any one but its author. Interplanetary water vapour and the periodical in- dulgence of the sun in cometary vapour baths appear to play an important part, the idea being that as a result of their action the radiant forces of the sun are confined within the limits of the solar system. The recurring absorption of the planets by the sun and subsequent disruption into new systems are other features of a theory which has its principal strength in the fact that there are no means of testing its chief teachings. The author’s name does not appear on the title-page, but the preface is signed by J. H. Brown. NO. 1565, VOL. 60] 615 Official Report of the National Poultry Conference held at Keading in July 1899. Edited by the Honorary Secretaries, Edward Brown, F.L.S., and F. H. Wright, F.S.A.A. Pp. xvi + 138. THE conference of which this is a report was the first of its kind held in this country, and its success should lead to other similar meetings. The report shows that most of the papers were of a scientific character, and its pub- lication should extend the knowledge of the principles which lead to successful poultry-farming. Among the subjects dealt with are: the science and practice of farm poultry keeping, the parasitic diseases of poultry, and the assistance afforded by science in the production of eggs and poultry. There will be hope for British agriculture when the spirit which pervades these papers guides the operations of all who are concerned with rural industries. The Story of Ice tn the Present and Past. Brend. Pp. 228. 1899.) AN instructive addition to the “Library of Useful Stories,” containing a clearly-written account of the physical properties and geological operations of ice. General readers should find the volume interesting. We notice that the cavities formed by glacier mills are termed “potholes or giant’s kettles” ; but the former term ought to be restricted to the circular holes found in the beds of streams. By W. A. (London: George Newnes, Ltd., LETTERS TO THE EDITOR. [The Editor does not hold himself responstble for opinions ex- pressed by his correspondents. Netther can he undertake to return, or to correspond with the writers of, rejected manuscrebts tntended for this or any other part of NATURE. No notice ts taken of anonymous communications. | Effect of Vibration on a Level Bubble. I HAVE never seen any notice of this phenomenon, but it is sufficiently curious to be worth describing. I had fitted on a bicycle a small level with a radius of curv- ature of a foot, in order to note gradients without dismounting. In general this answered very well, and the gradients could be satisfactorily measured with an accuracy of about I percent., but when going over certain classes of rough road (e.g. granite paving), the roughnesses of which had a definite pitch, it was noticed that though the road might be level, the bubble would at certain speeds indicate gradients as steep as one in eight or one in six, and remain steadily in such positions as long as the speed and character of the road remained constant. It seemed a matter of chance whether the bubble moved so as to indicate an up or a down gradient. The explanation is to be found in the coincidence of a natural period of the bubble, due to the surface tension of the fluid, and the interval which elapses between successive encounters of the bicycle wheel with the roughnesses of the road. Owing to the level being at a certain height above the ground (it was attached to the upper tube of the frame), any pitching of the bicycle, such as is caused by going over rough ground, gives a backward and forward motion to the frame in addition to the general onward movement. We may suppose, for the sake of simplicity, that this back- ward and forward motion is a simple harmonic. Whena level is subjected to a harmonic displacement parallel to the mean direction of the tube, the bubble will endeavour at each instant to place itself at that part of the tube where the tangent is at right angles to the resultant of gravity and the im- posed acceleration. Thus the bubble tends to move relatively to the tube in the direction of the displacement of the latter, and would always occupy its true position with regard to the re- sultant if its motion under the variable force was quick enough. The motion of the bubble, however, is very slow compared with that required to bring about this result ; but although the forces which act on the bubble have not time to move it far in each period, they do deform it, and the deformation may become 616 NALORE ~ [OcTOBER 26, 1899 large if the imposed force has the same frequency as any of the natural vibrations of the bubble. When the bubble is long, as in an ordinary level, the result when such a coincidence is reached is that the long bubble is broken up into a number of small ones, but in the bicycle level the bubble was small and nearly spherical. The slowest natural vibration which a spherical bubl le is capable of is that in which it becomes alternately a prolate and oblate spheroid. It would take too long to enter in detail into the character of the deforming forces acting on the bubble. They are of two kinds, one depending on the acceleration and the other on the velocity. The former tends to make the bubble egg-shaped (z.e. big at one end and small at the other) to a degree propor- tionate to the acceleration; the latter involves the ratio of the cross section of the bubble and tube, and tends to make the bubble oblate as the velocity increases. When the impressed motion has the same period as the bubble, the latter will pass through its zero position in opposite phases. . Thus, if in moving forwards it is an oblate spheroid as it passes through the zero, it will be prolate half a period later when re- turning backwards through the same position, but both the deforming force and resistance to motion through the fluid which the bubble experiences when prolate are less than when it is oblate, so that there is a balance in favour of the oblate de- formation, which will tend to increase and perpetuate a vibration once started. Since the resistance experienced by the prolate form is less than oblate resistance, the excursion of the bubble will be greater in the first case than the last, with the result that in time it will move to such a position that the slope of the tube there supplies a force sufficient to balance the difference of resist- ance met with in moving in opposite directions. In the accompanying diagram the direction of the level tube is supposed to be at right angles to the abscissa axis, which represents the time of one oscillation. AA displacement of level tube; BB displacement of bubble relatively to the tube; cc deforming force depending on the velocity ; 1, 2, 3, &c., the forms assumed by the bubble at various phases. There is some particular ratio between the diameters of the | bubble and tube, and some absolute diameter of the tube, depending on the surface tension and density of the fluid, which gives the maximum displacement, but even an approximate analytical solution of the problem would present great difficulties. ; In. the level experimented on, the surface tension of the fluid employed was 27 (in C.G.S.) and density 88. The radius of the bubble was "142 cm. and that of the tube 23 cm. (rough measurements). A spherical bubble of the radius given if surrounded by an unlimited quantity of fluid of this surface tension and density would have for the frequency of its slowest natural vibration 120 per second nearly (see Lamb, ‘‘ Hydrodynamics,” p. 463), but in the case under consideration the small distance between the sides of the bubble and tube must greatly diminish the frequency of this form of vibration. By experiment it was found that the greatest displacement occurred with a frequency between 40 and 50 per second, the bubble then being driven to the ends of the tube where the slope was about one in five. A. MALLock. 3, Victoria Street, October 3. Rural Education. THE Countess of Warwick and Prof. Meldola are entitled to all praise for their zeal in establishing the School of Science at Bigods, to which reference was made in your issue of October 5. There should, however, be some recognition of the similar NO. 1565, VOL. 60] work done by others in purely rural districts.. At Bruton, a village in Somersetshire, the success of such a school has been quite phenomenal. Sexey’s Trade School, as it is called, owes its inception to Mr. Henry Hebhouse, M.P., and was founded a few years ago out of the old endowments of Sexey’s Hospital under a scheme of the Charity Commissioners, with aid from the Somerset County Council. Recently I had an opportunity of seeing the school, and could not sufficiently admire the excel- lence of what is done there. The buildings consist of a master’s house, large schoolroom and lecture-rooms, well-equipped physics and chemical laboratories, wood and metal workshops, gymnasium, &c., with about two and a half acres of garden and playground attached. Besides instruction in the ordinary subjects of a higher primary or secondary school, the boys in the upper division (Classes II. to V.) are taught magnetism, electricity, chemistry, mechanics, manual work in cardboard, wood and metal, mensuration, French, botany and bookkeeping, and the instruction in technical subjects is throughout of a practical nature, being given in the garden, field, and work- shops, as well as in the class-room. Outdoor lessons are given in land measuring. Visits are occasionally paid to farms in the neighbourhood to inspect the stock, implements, buildings and crops. Botanical walks are taken at intervals in order to study plants in their natural habits, and the boys are encouraged to make collections of botanical and other specimens. Since 1896 the school has been organised as a School of Science, and through the courtesy of the headmaster, Mr. Knight, I am able to place the following details before your readers. The fees for tuition are 4/. and for boarding 20/. per annum. The school has been accepted by the Somerset and Wilts County Councils as one of those at which junior ana intermediate county scholars may attend. There are 103 boys at the school, of whom 25 are the sons of farmers, 20 of artizans, and 32 of small tradesmen. Of those who have left the school 34 have taken to farming. as an occupation. From the forty-fifth Report of the Science and Art Department it appears that in 1897 the school presented 63 pupils for examin- ation. The grant earned was 384/., being an average of 6/. 25. per head. The High School at Middlesbrough stood next on the list with an average of 5/. 13s. per head, and the general “average for the 143 organised Science Schools in Great Britain was 3/. 9s. 6d. Such an experience as this ought to be of the greatest encouragement to those who are really anxious for the improvement of rural education, and the facts cannot be too widely known. This school differs from the one at Bigods in that it is only for boys; but a school is now being erected in the immediate neighbourhood to provide a modern education for girls, corresponding as far as possible with that provided for the boys. Joun C, MEpp. Stratton, near Cirencester, October 15. THE good work being done at Sexey’s Trade School is of course well known to all who have interested themselves in rural education. Readers of NATURE will no doubt be glad to have Mr. Medd’s independent testimony, and more par- ticularly the detailed statement of figures concerning grants and fees. At the present time, when the subject of rural education is so very much before the public, it would, however, be of the greatest assistance to those who are engaged in carrying on this work if Mr. Medd could supply more detailed information concerning the aid which the County Council has given and how this assistance has been rendered ; whether in the form of grants for building and equipment or for maintenance of staff, or both, Also what proportion of the initial cost of foundation as a School of Science was contributed hy the Somersetshire County Council? In the present state of rural education one cannot help feeling that the whole future success of these schools is very largely dependent on the constitution of the Technical Instruction Committees of the County Councils— especially in those cases where the County Council has become recognised as the central authority. Any information, therefore, that can be given on these administrative points, either with respect to Sexey’s or any similarly constituted school, would be most opportune. In the case of our school at Bigods, the initial cost of foundation and conversion into a School of Science has been mainly borne by Lady Warwick. The Essex County Council, as regards maintenance of staff, have put us on the same footing as the endowed schools in the county by granting 100/. annually. R. MELDOLA. « OcTOBER 26, 1899] NATURE 617 ON THE DISTRIBUTION OF THE ark Us see them ; but there are reasons for supposing that there ; Bite re" en = Se 7a is a very considerable number. CHEMICAL GROUPS OF STARS We have deal with the masses of matter in CS! Y)ME few years ago it was my duty to give a course ~ of lectures here relating to the sun’s place in nature I attempted to give an idea of the relation of the sun, as to age and temperature, to other stars, and also its re- lation to bodies supposed to be of a different ordex altogether. Since that lecture was delivered our knowledge on this and allied subjects has advanced with giant strides. We now know, thanks to spectrum analysis, the principles of which I then explained, a great deal of the chemistry of the stars, so much that we can now classify them into groups, defining those groups by the chemical elements involved in each. I shall not bring before you to-night the detailed classi- fication of these bodies, but shall, for the purposes of this lecture, ask you to consider the four following kinds only : . Hishest temperature. f Proto-hydrogen stars. \ Cleveite-gas stars. Proto-metallic stars. Metallic stars. Stars with fluted spectra. Gaseous stars Lowest temperature. The table almost explains itself: I may add that by “ proto-metallic stars I mean those stars in the spectra of which the metals we know here are ehiefly represented by lines—the so- called “ enhanced-lines ”—we can only obtain here by using high-tension electricity, and there are other evi- dences which show that these stars are hotter than the metallic ones, while they, in their turn, are cooler than the gaseous stars. In discussing the work of other observers I have as far as possible transposed the different notations employed into the chemical one given above. In relation to the sun’s place we had a great many comparisons to make with different stars quite independ- ently of their position in space. I propose now to touch upon a still more general inquiry to consider the distribution of all stars in space, not in relation to their magnitudes, but in relation to their chemistry. It is obvious that we are among the first from the beginning of the Fic. world who have been able to do this, because formerly the chemistry of these celestial bodies was entirely lacking. I think, there- fore, you will agree that it is a very important thing, now that we have the chemistry, to inquire into the distribu- tion of the various chemical conditions in the different parts of the universe in which our lot is cast. For that purpose, I will deal with the stars as generally as I can, considering only the wider division into the gaseous stars, the proto-metallic stars, that is to say, the stars represented by the enhanced lines, then the metallic stars in which we are dealing with arc lines, and then the metallic fluting stars and the carbon fluting stars. As star-life begins with nebula and meteoritic swarms, it ends with dark stars which it is possible may be very numerous in space. How many there are we do not know, because we cannot lelivered at the Museum of Practical rman Lockyer, K.C.B., F.R.S 1 A Lecture to Working Men, yn April 10, by Prof. Sir N NO. 1565, VOL. 6o| 1.—Photograph of a g only to space which are visible, and it is obvious that any inquiry into the distribution of the chemical conditionings, as revealed by spectra, of these masses must be preceded by an inquiry into the distribution of these masses considered merely as masses and quite independent of chemistry. This work has already occupied the altenvion of many eminent astronomers, and I will begin by placing the results of their labours before vou as shortly as I can. I call your attention to the Milky Way. If you have seen the Milky Way from a high mountainous country, as I have done, you will acknowledge what a very wonderful zlass globe showing the relation of the Milky Way to the Equator an to Gould's belt of stars. thing it is; I was most struck with the Milky Way when I was in the Rocky Mountains some years ago. It was not merely the pale milky belt we generally see running across the sky, but it had lights, shades, shadows, brightnesses and dimnesses ; it was full of the most ellous details. I have seen it, I am bound to say, Kent, but not often. You mary just as well on the coast of want an extremely fine sky to see the Milky Way properly ; but, at all events, whether you have seen it well or ill, all of you, 1 am sure, are familiar more or less with it. What is it? It is a-bnght belt encircling the heavens ; its position with regard to the equator of the earth, and the equatorial plane extended to the stars, I can show you roughly by means of a glass globe. Those who are familiar with Dante know that the old view of the heavens was that the earth was immovable in the 618 centre ; that there were several heavens round it: the heaven of the moon, the heaven of Venus, of Mars, and so on, till at last there was a heaven of the stars, a crystal- line sphere to which the stars were fixed like golden nails. Let the glass globe represent this crystalline sphere. The Milky Way is a great circle inclined, at an angle of about 62°, to the earth’s equator or to the equatorial plane extending to the stars. We know nothing, of course, of the reason for that angle of 62°, but it has its importance, because not only must the belt cross the equator at two opposite points, as it does in two opposite constellations, Aquila and Monoceros, but the poles of the Milky Way must lie at the points of greatest distance from the junction with the equator, in certain constel- lations. These are Coma Berenices and Sculptor, and the position of the N. galactic pole, as the pole of the Milky Way is called, is in R.A. 12h. 4om. Dec. + 28°. Now, although the Milky Way looks very unlike the other parts of the heavens, we have known since the time of Galileo that the difference arises from the fact that it is composed of a tremendous multitude of stars ; and this is why I have drawn attention to it, a very large percentage of the masses of matter which compose our system lies in the plane of the Milky Way. It does not merely represent a fiery or igneous fluid, as different schools thought it did in the old days. So far as our opera-glasses and telescopes indicate to us, we are in presence of an innumerable multitude of stars. When, however, we come to look at it a little more closely, we find that from two points in it branches are thrown out, so that over some part of its orbit, so to speak, it is double ; there isa distinct doubling of the Milky Way along a partof its length. But in spite of that, the middle line of the galaxy or the Milky Way is really not distinguishable from a great circle, as was formerly supposed. The great rift which separates these two parts of it begins near a star in the southern hemi- sphere, a Centauri, and it continues for more than six hours in right ascension until the two branches meet again in the constellation Cygnus, which is well within our ken in the northern heavens. The distance apart of the middle lines of these two components of the Milky Way where the split is most obvious is something like 17°, so that, in addition to the angle of 62° from the ecliptic, in some part of the Milky Way, there is another offshoot springing out of it at an angle of something like 17. The regions of greater brilliancy correspond approxi- mately to the places where the branches intersect each other. In short, there are sundry indications that the whole phenomena of the Milky Way may become simplified by treating it as the resultant of two super- imposed galaxies. The general view till recently was that the Milky Way is not a great circle, because it was thought the sun was not situated in its plane. The whole mass of stars was likened to a millstone split along one edge, which was Sir William Herschel’s first idea. But the recent work, chiefly of Gould in Argentina, has shown that it practically is a great circle. However that may be, in one part of the heavens this wonderful Milky Way appears as a single, very irregular stream, and in another part it appears to be duplicated. It is impossible in this short course of lectures to attempt to give anything like an historical statement of the growth of our knowledge of the Milky Way. I can only refer you to the Milky Way itself ; and the next time any of you have an opportunity of seeing it, just look at the wonderful majesty and complexity of it. We find in it indications of delicate markings going out into space, apparently coming back strengthened, of streams in all directions, of clusters clinging to those streams, and so on. In other parts it is curdled, which is the only term which I can use to express my meaning. In another part we may find it absolutely free from any important stars; in another we may find it mixed with obvious nebula ; and in another we may find it mixed, not NO. 1565, VOL. 60] NATURE [OcToBER 26, 1899 only with obvious nebula, but with a great number of bright-line stars involved, not only in the Milky Way, but in the nebula itself. We have now, fortunately for science, priceless photo- graphs of these different regions. One will give us an idea of the enormous number of stars in some parts ; another one of the streams of nebrlous matter which are seen in the Milky Way from region to region. Again we find a regular river of nebulous matter rushing among thousands of stars. In some the galaxy seems to tie itself in knots. There is an individuality in almost every part of it, which we can study on our photographic plates ; practically there are no two parts alike. Others again bring before us the curdled appearance which is visible in different regions, and finally the connection of the infinite number of stars with obvious nebulous matter. In this way, then, we are enabled to form an idea of the general conditioning of things as we approach the Milky Way. The next important point is that the enormous in- crease of stars in the Milky Way is not limited to the plane itself, but that there is really a gradual increase from the poles of the Milky Way, where we get the smallest number of stars. It is not very easy to bring together all the information, for the reason that different observers give different measures; they take different units for the space they have determined to be occupied by stars from the pole towards the galactic plane ; and also the number of stars in the northern hemisphere is not the same as the number in the southern hemisphere. But roughly speaking we may say, if we represent the number of stars at the galactic pole by four, the number of stars in the galactic plane will be about fifty-four. The following table will show the gradual increase in the number of stars from the pole to the plane, as seen by the Herschels with a reflecting telescope of eighteen inches aperture and twenty feet focal length :— ! Average number of stars per field of 15’ Galactic polar distance. 3 are Northern. Southern. ° wy | O-15 4°32 | 605 WS 32) 5°42 6°62 30-45 8°21 9 08 45-60 13°61 | 13°49 60-75 24°09 | 26°29 75-90 53 43 59°06 A consideration of the distribution of stars in Right Ascension between declinations 15° N. and 15° S. led Struve to the conclusion that there are well marked maxima in R.A. 6h. 4om, and 18h. 4om., and minima in R.A. th. 30m. and 13h. 3om.; he remarks that the maxima fall exactly on the position of the Milky Way in the equator, and further states that “the appearance of the close assemblage of stars or condensation, 1s closely connected with the nature of the Milky Way, or that this condensation, and the appearance of the Milky Way, are identical phenomena.” * Although the Milky Way dominates the distribution of stars, and especially of the fainter stars, it does not appear to be the only ring of stars with which we have to do. Sir John Herschel traced a zone of bright stars in the southern hemisphere, which he thought to be the projec- tion of a subordinate shoot or stratum. That was the first glimpse of a new discovery, which was subsequently established by Dr. Gould in his work in the southern hemisphere at Cordova. He found that there was a stream of bright stars to be traced through the entire circuit of the heavens, forming a great circle as well de- 1 Outlines of Astronomy, Herschel, pp. 535, 536- OcToBER 26, 1899 | NATURE 619 fined as that of the galaxy itself, which it crossed at an angle of about 25°. Gould, while in the southern hemisphere, had no diffi- culty in observing that along this circle, which we may call the Star-way, in opposition to the Milky Way, most of the brighter stars in the southern heavens lie. When he subsequently came home he made it a point of study to see whether he could continue this line of bright stars among the northern hemisphere, and he found no difficulty. So that we may now say that the existence of this supplementary Star-way, indicated by the line of extremely bright stars, is beyond all question. I quote the following from what Gould has written on this subject. “Few celestial phenomena are more palpable there than the existence of a stream or belt of bright stars, in- cluding Canopus, Strius, and Aldebaran, together with the most brilliant ones in Carina, Puppis, Columba, Canis Major, Orion, &c., and skirting the Milky Way on its preceding side. When the opposite half of the galaxy came into view, it was almost equally manifest that the same is true there also, the bright stars likewise fringing it on the preceding side, and forming a stream which diverging from the Milky Way at the stars a and 8 Centauri, comprises the constellation Lupus, and a great part of Scorpio, and extends onward through Ophiuchus towards Lyra. Thus a great circle or zone of bright stars seems to gird the sky intersecting with the Milky Way at the Southern Cross, and manifest at all seasons, although far more conspicuous upon the Orion side than on the other. Upon my return to the North, I sought immediately for the northern place of intersection ; and although the phenomenon is by far less clearly perceptible in this hemisphere, I found no difficulty in recognising the node in the constellation Casszopeza, which is diametri- cally opposite to Cvzx. Indeed it is easy to fix the right ascension of the northern node at about oh. 50m., and that of the southern one at 12h. 50m. ; the declination in each case about 60°, so that these nodes are very close to the points at which the Milky Way approaches most nearly to the poles. The inclination of this stream to the Milky Way is about 25°, the Pleiades occupying a position midway between the nodes.” , Gould also had no difficulty in showing that the group of the fixed stars to which I have just referred, at all events of fixed stars brighter than the fourth magnitude, is more symmetrical in relation to this new star line than to the Milky Way itself, and that the abundance of bright stars in any region of the sky is greater as the distance from this new star line becomes less. Practically five hundred of the brightest stars can be brought together into a cluster, independent of the Milky Way altogether—a cluster he points out of somewhat flattened and bifid form. Not only do we find that the stars are very much larger in number near the Milky Way than elsewhere, but that the same thing happens with regard to the planetary nebule. Nebulz generally, 1 am sorry to say, I cannot profess to’ discuss with any advantage, because there are very many bodies classed as nebulz in the different cata- fogues about which we know absolutely nothing as to their physical nature. It will be remembered that many years ago the question of the real existence of nebulous matter in space was rendered very difficult by the fact that the larger telescopes, which were then being made by Lord Rosse, brought before us a great number of clusters, the stars of which were so close together that they seemed to form a nebulous patch, whereas on a finer night or with a better instrument we were able to see that we were simply dealing with distant clusters. I do not propose, therefore, to say anything about nebulz generally, but to 1 Amer. Jour. Scé., Vili. Pp. 332+ NO. 1565, VOL. 60] call attention to those points about which we can be most certain. We do know that, not only do we find stars increasing in number as the Milky Way is approached, but the un- doubted star clusters also increase towards the Milky Way ina marvellous manner. Bauschinger! (1889) in a review of Dr. Dreyer’s New General Catalogue (7840 objects) discussed the distribu- tion of different classes of objects and found that star clusters, by which he means of course resolved clusters, and planetary nebulee congregate in and near the galaxy. Mr. Sydney Waters some four years later, in 1893, brought together the nebulae and the star clusters for us, and I propose to show the very important maps which he drew. He indicates a star cluster by a cross, and nebulz by round dots. Practically the obvious star clusters are limited to the Milky Way. That isa very admirable way of bringing the knowledge with regard to any one of these distinct groups of stars before us, and it shows us ina most unmistakable manner that the star clusters, like the planetary nebulz and stars generally, are very much more numerous in the plane of the Milky Way than they are in any other part of the heavens. It is striking to note the fidelity with which the clusters follow, not only the main track of the Milky May, but also its convolutions and streams, while the remarkable avoidance of the galaxy by the nebule, excluding the planetary nebulze, is obvious, indeed, it was remarked upon by Sir Wm. Herschel. We have seen, then, that we have the greatest number of stars congregating in the plane of the Milky Way, the greatest number of planetary nebulz and the greatest number of star clusters. We have next to consider whether any particular kind of a star congregates in the Milky Way or avoids it. In that way we shall be able to see the importance of this new chemical touch, which is now possible to us in our survey of the heavens. The first attempt at such an inquiry as this was made in 1884 by Dunér,? who had made himself famous by his admirable observations on two different classes of stars —those which I have referred to as being defined by carbon flutings in one case and metallic flutings in the other. His work was practically the only research on the carbon stars—the stars, that is, with carbon flutings. He was, naturally, anxious to see how they were distributed, and he gives the number of these stars in varying parts of the heavens in relation to the Milky Way. He found that the numbers increased towards the Milky Way. The table I give will show the general result at which he arrived. We had, as we saw in the case of the ordinary stars, a very rapid progression in number from the pole of the Milky Way to the plane ; we had three stars at the pole when we had fifty-three in the plane. | Dist. from galactic pole. Number. Mean mag. 0-3 3 6°6 35-60 8 66 60-70 8 Taz) 70-80 13 74 29 83 80-90 | Duner found, with regard to his carbon stars, that there was distinctly an increase from the pole towards the plane, but we observe that the rate of increase was very much less in this case; so that, starting with three at the pole, he only found twenty-nine in the plane. Although then it was. true that the number of stars did increase towards the Milky Way, they did not increase so rapidly as the stars taken as a whole; still, from his observations, we are justified in stating that 1 VSS. Ast. Ges., xxiv. p. 43. 2 **Btoiles de la trois¢me Classe,” p. 125. Plane of Milky Way 620 there is an increase as we approach the plane of the Milky Way. They are, therefore, not limited to the plane. Now we know that these stars are the moribund stars, the stars just disappearing, the stars whose light is waning ; so that soon after the carbon stage they exist in the heavens as dark stars, and we can only know their existence by their gravitational effect upon other stars which are self-luminous. It is also to be borne in mind that these stars, just because they are in their waning POLE 40 20 4O 60 yo Nun bers Fic. 2.—Comparison of relative numbers of stars generally and carbon stars. stage, are very faint ; so that the information we are able to get with regard to them may possibly be information concerning their distribution in parts of space not very far distant from that which we ourselves occupy. That was in 1884. In 1891 Prof. Pickering, when he found that he had collected something like 10,000 stars in the Draper catalogue, began to consider their dis- tribution in different parts of space in relation to the then classification, which was practically a classification founded on hieroglyphics, since we knew very little about the chemistry of the different bodies at that time. He found that the Milky Way was due to an aggrega- tion of white stars, by which he meant, as we now know, very hot stars, and the hottest of them, that is the gaseous ones, exist more obviously in the Milky Way than do the others. The proportional number of proto- metallic stars in the Milky Way was greater for the fainter stars than for the brighter ones of this kind, and that at once suggests a possibility that in the Milky Way itself there is a something which absorbs light ; so that the apparently brightest stars are not actually the brightest, but are more luminous because they have not suffered this absorption, and that those which have suffered this absorption may be very much further away from us than the others of a similar chemistry. He also arrived at this extremely important conclusion, namely, that the metallic stars, that is, stars like our sun, stars more or less in their old age, had no preference for the Milky Way at all, but are equally distributed all over the sky. With regard to the group of stars known by metallic flutings in their spectra, he has no information to give us any more than Dunér had, for the reason that their number is small and they have not yet been completely studied. Only last year this inquiry was carried a stage further by Mr. McClean, who not only photographed a considerable number of stellar spectra in the northern hemisphere, but subsequently went to the Cape of Good Hope in order to complete the story with reference to the stars down to the third or fourth magnitude, which he could observe there. He was very careful to discuss, in relation to the Milky Way and certain galactic zones, the distribution of the various kinds of stars which he was fortunate enough to photograph. We notice that if we deal with the gaseous stars the numbers in the north and south polar region are small, and that the numbers nearer the Milky Way are greater, so that finally we can see exactly how these bodies are NO. 1565, VOL. 60] NATURE [OcToOBER 26, 1899 distributed. If we take the gaseous, that is to say the hottest, stars, we find the smallest number in the polar regions ; but if we take the metallic stars we find practically the largest number, at all events a considerable number, in the polar regions. The general result, therefore, is that the gaseous stars are mostly confined to the galactic zones, the proto-metallic stars are not so confined, that is to say, down to about 34 magnitude. What is also shown there is that the metallic-fluting stars are prac- tically equally distributed over the polar regions and over the plane of the Milky Way itself; so that, in that respect, we get for these stars very much the equivalent of the result arrived at by Dunér, that is to say, they have little preference for the Milky Way. (To be continued.) THE PARENT-ROCK OF THE SOUTH AFRICAN DIAMOND. IAMONDS were discovered in gravels of the Orange River in 1867, and were traced three years later to a peculiar earthy material called from its colour “ yellow ground” by the miners. This, which was soon found to pass down into a more solid and dark-coloured material called “blue ground,” occupies ‘‘ pipes” in the country rock—carbonaceous shales and grits belonging to the Karoo system ; the one standing in much the same relation to the other as do the volcanic necks to the carboniferous strata in Fifeshire. Flows or sills of basaltic rocks are associated with the sedimentary strata, and both are cut by dykes. The matrix of the blue ground is a fine granular mixture, chiefly consisting of a carbonate (calcite or dolomite) and serpentine. In this are em- bedded grains of garnet (mostly pyrope), pyroxenes (a chrome diopside, smaragdite or enstatite), a brown mica, magnetite and other ores of iron, and some other minerals more sparsely distributed. Rock fragments also occur; some of them are the ordinary shale and grit, but others are compact and of an uncertain aspect. Crystalline rocks are sometimes found. As to the nature of this blue ground and the origin of the diamond, very diverse opinions have been expressed. The late Prof. Carvill Lewis considered the former to be a porphynitic peridotite, more or less serpentinised, which sometimes passed into a breccia or a tuff, and the diamond to have been formed zm sz¢z by the action of this very basic igneous rock upon the carbon present in the Karoo beds. Others, however, maintained that the rock was truly clastic ; being produced by the explosive destruction of the sedimentary rocks, together with part of their crystalline floor—was, in fact, a kind of volcanic breccia, subsequently altered by the action of percolating water at a high temperature. But they also differed in opinion as to the genesis of the diamond itself ; one party holding it to have been formed 77 szfu, by the action of water at a high temperature and pressure, the other considering it, like the garnets, pyroxenes, &c., to have been formed in some deep-seated holocrystalline rock mass, and to have been set free, like them, by explosive action. A few months ago the investigation had advanced thus far: (1) study of the diamonds obtained from the blue ground had increased the probability of their being derivative minerals ; (2) no certain proof of the former existence of a compact or glassy peridotite had been dis- covered ; (3) certain compact rock fragments, as to the origin of which the writer had at first hesitated to express an opinion, had been determined by him to be only argil- lites, affected first by the action of heat, then of water ; (4) the diamond and the garnet had been brought into very close relation by the discovery of two specimens, showing the former apparently embedded in the latter. The better of them was accidentally picked up at a depth of about 300 feet in a shaft at the Newlands Mines, West 1 The substance of a paper read before the Royal Society on June 1. OctToBER 26, 1899] NATURE 621 Griqualand (about forty-two miles to the north-west of the more famous group in the neighbourhood of Kim- berley). In this specimen a rather large and irregularly shaped pyrope projects from one end of a fragment of blue ground : one small diamond is embedded in this pyrope, and five others either indent it or are in close contact. Fortunately the discoverer was the managing director of the company, Mr. G. Trubenbach, who appreciated its importance, and so kept a sharp look- out for anything remarkable which might turn up during the excavations. Accordingly he preserved specimens of certain boulders, sometimes over a foot in diameter, well rounded and just like stones from a torrent, which oc- casionally occurred in the blue ground at various depths down to 300 feet. Several of these contained garnets, being varieties of eclogite, but diabase was also obtained.! Some of these Mr. Trubenbach brought to London, and on the outer surface of one a small diamond was detected. The boulder was broken, and others were exposed. A fragment (rather less than a third) was sent to Sir W. Crookes, who entrusted it for examination to the writer, and to him Mr. Trubenbach afterwards sent other boulders, besides rock and mineral specimens, with the permission of the directors. In addition to the boulder of diabase, which has no special interest beyond the fact of its occurrence, there are six boulders of eclogite (one perfect, the rest having been broken), all but one (which may have been four or five inches long) measuring a foot across, more or less. Three of these consist almost entirely of a garnet (pyrope) and an augite (chrome diopside), the former varying in size from a large pea downwards, and the other mineral corresponding. The pyrope is often sur- rounded, especially towards the exterior of the boulder, by a “kelyphite rim ” consisting mainly of a brown mica. This and a few other minerals were present elsewhere, but in very small quantities. The remaining three boulders consisted of the same two constituents, with the addition of a considerable amount of a variety of bastite and a few flakes of brown mica. Of the first group of specimens two contain diamonds, the first-named having at least nine and another certainly one, perhaps a second. All are small, the largest being about ‘15 inch in diameter. They are well-formed octahedra, with slightly stepped faces, perfectly colourless, with an excellent lustre. Evidently they are just as much an accidental constituent of the eclogite as a zircon might be of a granite or syenite. This discovery leads to the following conclusions. As the diamond is found in boulders of eclogite, and these are truly water-worn, that rock is the birth-place, or at any rate one birth-place, of the diamond (for its occurrence in a more basic species, such as a peridotite, may be ex- pected). Hence the diamond is not produced in the blue ground, but is present in it as a derivative from older rocks, in the same way as the olivine, the garnets, the various pyroxenes, &c. Moreover, the blue ground is a true clastic rock, and not a serpentinised peridotite of any kind, so that the name Kimberlite, proposed for it by Prof. Lewis, must disappear from that group. The rock is a volcanic breccia, though a rather peculiar one, for scoria has not yet been detected in it. Probably it was formed by explosions due to pent-up steam, the vents being driven through the upper part of the crystalline floor and the overlying sedimentaries. These never ejected lava, and were soon choked up with shattered material. Through this, in all probability, steam or heated water continued to be discharged for a considerable time, which accounts for the marked changes effected in the exterior of the larger fragments and in the more finely pulverised material of the matrix. T. G. BONNEY. 1 The occurrence of boulders in the blue ground at De Beers Mine was EY by Stelzner in 1893 (Sztsungber. u. Abhandl. der Isis, 1893; p- 71). NO. 1565, VOL. 60] NOTES. WE are informed that copies in bronze of the medal presented to Sir G. G. Stokes at his jubilee can now be obtained from Messrs. Macmillan and Bowes, Cambridge, price 15s. each. AT the opening meeting of the new session of the Institution of Civil Engineers, on November 7, an address will be given by the president, Sir Douglas Fox, and the prizes and medals awarded by the Council will be presented. A GOLD medal is offered by the Cercle industriel agricole et commercial, Milan, for the description of a method, or the con: struction of apparatus, which will assist in the prevention of accidents to artizans engaged in electrical work, A CONVERSAZIONE of the Geologists’ Association will be held in the library of University College on Friday, November 3. A number of pictures and objects of geological interest wilt be on view during the evening. TuE Allahabad Pioneer Mail (October 6) states that Mr. Douglas Freshfield has started from Darjeeling, with a party of friends and Alpine guides, to explore the glaciers and little- known passes of the Kanchenjunga range. The exact course to be pursued is probably unknown to the party themselves, who must be guided by circumstances ; but any addition to the scanty and inaccurate information at present extant on the subject of the Himalayan giant will be welcome to geographers. Ir is stated that another British exploring expedition to Abyssinia has been arranged, and will leave England at once. The members are Mr. James J. Harrison, Mr. Powell Cotton, Mr. W. Fitzhugh Whitehouse (of Newport, Rhode Island) and Mr. A. E. Butter. Mr. Donald Clarke will go as surveyor and geographer, and a taxidermist will also accompany the party. The objects of the expedition are scientific and sporting, and it is expected that the journey will occupy about nine months. THE thirty-eighth annual general meeting of the Yorkshire Naturalists’ Union is to be held at Harrogate to-day, and an address upon the evolution of plants will be given by Mr. William West, the retiring president. The Union is a model of a well-organised local society, which not only serves to develop interest in science, but also assists in the extension of natural knowledge. The membership is not in any way com- mensurate with the importance of the work carried on, and we are glad to see that efforts are to be made during the forthcoming winter to bring the claims of the Union for support before the naturalists and the public of the County of York. THE Sritish Central Africa Gazette, published at Zomba, always contains several items of scientific interest, and the latest number received, dated August 24, is not deficient in this respect. We learn from this source that Mr. J. E. S. Moore has been taking soundings at the north end of Lake Nyasa. Off Ruarwe a depth of 418 fathoms was found, and off the higher parts of Livingstone Range bottom was reached at 210 fathoms. —Mr. Poulett Weatherley describes in a letter a difficult journey up the Luapula, and through its innumerable rapids. The Luela is regarded as the second most important tributary of the Luapula, but there is little to choose between the Luombwa, the Luela, the Mwyangashe and the Luongo, though the Luombwa is the largest and most delightful of the four. REUTER’S correspondent with Major Gibbons’ trans-African expedition reports from Lialui (Barotsiland), in a despatch dated August 5, that much valuable exploring work had been done by the members of the expedition, The routes traversed by the travellers since last January amount in the aggregate to 3500 miles, mostly through unknown or unexplored districts. 622 NATORE [OcToBER 26, 1899 The plans of the party at the date of the despatch are reported to have been as follows :—At the end of this month Captains ‘Quicke and Hamilton will travel east to the Kafukwe, while Major Gibbons will make a journey up the Zambesi with canoes to Nanakandundu, returning by river as far as the Kabompo -confluence, whence he will make a line to the Kafukwe. Captain Hamilton will then travel down that river to its con- fluence with the Zambesi, where an aluminium boat awaits him, in which he will descend the river to Zumbo, and return home wa the east coast. Major Gibbons with Captain Quicke will travel up the Kafukwe, and, after following the Zambesi from its source to Nanakandundu, will make for St. Paul de Loanda on the west coast. All three hope to reach the coast in December by their respective routes. THE long-standing question as to the admittance of women into full fellowship of scientific societies was brought before a meeting of the Lady Warwick Agricultural Association for Women on Thursday last, and the following resolution, sup- ported by a paper by Mrs. Farquharson, was adopted: ‘‘ That it is desirable and important that duly qualified women should have the advantages of full fellowship in scientific and other learned societies, e.g. the Royal, the Linnean and the Royal Microscopical.” The arguments in favour of and in opposition to this proposal have been stated so many times that most members of scientific societies are familiar with them. Six years ago the Council of the Royal Geographical Society elected several ladies as fellows, but their action was disapproved at two special meetings, and resolutions to the effect that it was inexpedient to admit ladies as ordinary fellows were carried by conclusive votes. Ladies are, however, admitted to the meet- ings of the Society, and papers are accepted from them. In the case of the Royal Astronomical Society, ladies are only admitted to the ordinary evening meetings by special invitation of the president, sanctioned by the Council, the invitations being issued at the commencement of each session. The time may of course come when women will be equally eligible with amen for membership of the learned societies, but facts such as those cited show that there is distinct opposition to the admit- tance of women at present, and no sudden change of feeling can be expected, though individual cases of ‘‘ duly qualified” women might be considered. In a review which appeared in NATURE of September 7 (p. 433), reference was made to the hair of a ‘‘ Panyan woman,” figured as a ‘‘ Negrito type, India,” in Prof. A. H. Keane’s work on ‘‘ Man, Past and Present.’’ Mr. Thurston’s original photograph, from which the illustration was reproduced, shows the hair of the woman as of a distinctly curly character, ‘* which feature,” the writer of the review remarked, ‘‘ is unfortunately lost in Keane’s reproduction.’” Prof. Keane writes to say that his picture is a facsimile of Mr. Thurston’s photograph, and shows the curly hair portrayed in the original. In support of his case he has submitted the portrait and the reproduction to us, and we must confess our inability to distinguish any obvious difference between them. The writer of the notice maintains, however, that the hair is not quite the same in the two, and he unites with Prof. Keane in the hope that every one interested in the {matter will compare the illustrations for themselves before accepting either view. Dr. C. Le NEVE Foster reports, in a Blue Book just issued (‘‘ Mines and Quarries: General Report and Statistics for 1898,” part iii.), that the total value of all minerals raised in the United Kingdom in 1898 exceeded 77,000,000/., being an increase of five millions compared with the previous year. The output of coal during the year exceeded 202 million tons, of which 364 million tons were exported. This darge export of coal induces Dr. Foster to call attention to the NO. 1565, VOL. 60] ' runs within ten or twelve miles of that sanatorium. plain warning contained in Mr. T. Forster Brown’s paper on ‘© Our Coal Supplies” (Journal Society of Arts, 1899, p. 508), in which it is emphatically stated that in another fifty years the dearth of cheap coal will begin to be felt. Referring to this, Dr. Foster says: ‘‘We are already dependent upon foreign countries for much of our iron ore, and it will be an evil day when we feel the pinch of poverty in coal. The proper husbanding of the coal resources of the kingdom is therefore a question of national importance.” THE great success of the installations for the development of electricity by power obtained from Niagara Falls is naturally leading enterprising capitalists in many other parts of the world to consider similar projects. We learn, for instance, from the Pioneer Mazl that within the last few months schemes have been ventilated for utilising the Nerbudda at the Marble Rocks for supplying power to the new gun-carriage factory to be erected near Jubbulpore. There is also a project for running the Kashmir railway by electricity, the power being taken from the Chenab. Then there is another plan for supplying electrical power to Murree, deriving the energy from the Jhelum, which For Simla there are no less than two schemes for obtaining electrical power by hydraulic means : one from the Sutlej, and another from a pro- posed lake to be made in the nullah below the station. Assuming that the majority of these schemes are practical, the point which remains somewhat obscure for the present is whether the demand for electricity in any of the places named would be sufficiently great to make the undertaking a commercial success. THE Experiment Station Record (No. 5) of the U.S. De- partment of Agriculture contains a description of the biological and dairy building recently completed by the New York State experiment station at Geneva. The building has been con- structed and equipped by the State for the study of dairy problems, and especially those concerned with cheese-making. The changes which take place during the curing of cheese, and the conditions which influence them, are still so imperfectly understood that the work carried on in the new laboratories is sure to lead to valuable results. Arrangements are provided for studying the ripening process in all its phases; and a bacteriologist is attached to the staff. A NUMBER of excellent photographs obtained with a tele- photo lens, by Mr. D. L. Elmendorf, are reproduced in the current number of Scrébner’s Magazine. A telephoto attach- ment, consisting of a negative lens, with a rack and pinion mounting, was used upon an ordinary rectilinear lens to take the pictures. With this attachment eight inches from the plate, the image obtained was equal to that formed by an ordinary lens of twenty-four inches focus ; while at twenty-four inches from the plate, this being the greatest extension of the camera em- ployed, the combination was equivalent toa lens of sixty-four inches focus. Among the striking pictures which accompany Mr. Elmendorf’s article are views of the Jungfrau, obtained at a distance of sixteen miles, and of the cone of Popocatepetl, Mexico, taken at a distance of thirty miles. THE Pilot Chart of the North Atlantic Ocean for the current month contains some further interesting particulars respecting the track of the destructive West India hurricane of August 3- September 12. After leaving the American coast it at first moved eastward with increased velocity. During the week of August 24-30 it remained almost stationary in the mid-Atlantic, the centre of the disturbance shifting to the northward, from where it took an almost due easterly course to about longi- tude 20°, traversing the Azores on September 3 ; it then curved to the N.E. until it reached the vicinity of Brest on September 7, when it bent in a S.E. direction and reached the north of OcToBER 26, 1899 | NATURE 623 Corsica on September 9. Whole gales were frequently en- countered throughout the course of the storm across the Atlantic. Off the coast of Provence it caused strong N,W. gales and a rough sea on September 9-11. This hurricane can be traced over the North Atlantic for a period of thirty-six days, making it in length of life the most noteworthy storm ever reported to the Hydrographic Office in Washington. A sUMMARY of divers and sundry views respecting the cause of formation of hail is given by Signor Pio Bettoni in the Bolletino mensuale of the Italian Meteorological Society. The great divergence of opinion on the subject seems to suggest that we have not made much advance towards arriving at a definite explanation of the phenomenon during the century which has elapsed since Volta published his well-known electrostatic theory. Of the views here enumerated some are modifications of Volta’s theory, and attribute the formation of hail to electro- static causes, others ascribe the phenomenon to whirlwinds (vortices), others, again, to refrigerating air currents, and even the more unconventional theories, according to which hailstones come to the earth from interplanetary space or their refriger- ation is due to transmutation of caloric into electricity, are not without their advocates. In Himmel und Erde for September, Dr. E, Less, of the Berlin Meteorological Office, gives a very lucid account of the general circulation of the atmosphere. In the first half of this century our knowledge of weather changes was almost ex- clusively confined to climatological investigations, in which Prof. Dove, of Berlin, was the most prominent representative ; he referred the origin of all winds to an interchange of the air between the equator and the poles. But the study of synoptic weather charts, from about the year 1860, showed that the explanation hitherto given of weather changes did not generally accord with observed facts, and that they were intimately con- nected with the existence of areas of high or low barometrical conditions. The author points out that while the behaviour of the great atmospherical currents is, generally speaking, capable of explanation, the relation between them and the smaller dis- turbances which occur in our latitudes leave many doubtful points to be cleared up. In fact, what part is played by the general and what by the local conditions in producing the different phases of weather is as yet but little understood. The explanation of these phenomena is one of the most important problems of meteorological research, the solution of which must be approached in various ways. THE Bulletin International of the Cracow Academy contains anotice of a paper, by M. P. Rudski, on the theory of the physics of the earth. In it the author gives a mathematical investigation of the variation of latitude in an elastic spheroid covered with water, and investigates the earth’s rigidity as deduced from the 430-day period of the variation. The values deduced depend on the assumed “‘ effective density” of the earth. Taking for this density the values 2°2, 3:0, 4°0, 4°5 and 5°5, Rudski finds the corresponding values of the rigidity to be 567, 879, 1713, 2036 and 2681 times 10° C.G.S. units respectively, that of steel being 819% 10%. By neglecting the effects of the ocean, and taking for the effective density the value 5°5, the author finds 7 = 1250 x 10%. WITH a view of contributing data towards the determination of the secular variations of the earth’s magnetism, Dr. Emilio Oddone contributesto the Rendicontd del R. Istituto Lombardo, xxxii. 15, his determinations of the magnetic elements at Pavia for June 1898, which admit of comparison with the corre- sponding elements determined by him at the same spot about fifteen years ago. The present results are as follows: declin- ation, 11° 48’ + 2’; inclination, 61° 26’ + 2’; intensity in NO. 1565, VOL. 60] C.G.S. units, horizontal, 0°216, + o*001; vertical, 0°3973 ; total, 0°452,. While the interval between the present and the previous determination is too short to allow of these observations being made the basis of a new determination of the secular vari- ations of the earth’s magnetism, the author remarks that the empiric formulz for the inclination and horizontal intensity, when exterpolated for fifteen years, agree fairly well with the above-mentioned numbers, but the annual variation in late years comes out to be less than was to be inferred from past observations. Prors. ELSTER AND GEITEL, writing in Weedemann’s Annalen, 69, discuss the source of energy in Becquerel rays, and advance the theory that the rays may be due to changes of the molecular arrangement of the atoms of the radio-active substance in which these pass from an unstable toa stable configuration with expenditure of energy. Ina second note, the same authors show that Becquerel rays experience no deviation from a magnetic field, but that such a field in certain circumstances decreases the electro-dispersive power of air that has been traversed by them. IN a communication to Wiedemann’s Annalen, 67, Herr K- Kahle describes at some length experiments with the silver voltameter and their applications to determine the electromotive force of normal elements. The object of the paper is to obtain the electromotive force of the Clark cell, previously determined by the author by means of Helmholtz’s electro-dynamometer, independently from the electro-chemical equivalent of silver. The value now obtained for the ratio of the Clark at 15° to the cadmium at 20° is 1740663. Herr Kahle infers the following results as correct to 2 in 10,000, viz. Clark, 15°: 1°4328;; cad- mium, 20°: 1'0186,; and Clark, 0° : 1°4492 internal volts. Dr. FRANZ KERNTLER has published a paper on the unity of the absolute system of units in relation to electric and magnetic measurements, in which hé proposes to supersede the present dual systems of electrostatic and electromagnetic units. According to Dr. Kerntler’s system, quantity of electricity and quantity of magnetism are both measured by Coulomb’s law in C.G.S, units, and are thus both of the same dimensions, being identical with the electrostatic and magnetic units respectively ; but a current has two measures, which Dr. Kerntler designates as its ‘‘opulence”’ and its ‘ fecundity.” These, which represent its electromagnetic and electrostatic measurements in common parlance, are in the ratio of 1 to **v,” Dr. F. J. ALLEN has contributed to the Proceedings of the Birmingham Natural History and Philosophical Society, xi. 1, an essay on the nature and origin of life. The author remarks. that the most prominent and perhaps most fundamental phenomenon of life is what may be described as the energy’ trafic or the function of trading in energy. After briefly pointing out the differences between anabolism and catabolism, Dr. Allen advances the opinion that it is nitrogen which, in virtue of its variability, instability, and lability, plays the most important part in the phenomena of life, and he enunciates the law that every vital action involves the passage of oxygen either to or from nitrogen. In the section dealing with the origin of life, it is stated that life in its physical aspect is the culmination of that chemical instability in certain elements which has always kept them circulating at the earth’s surface. Dr. Allen considers that existing conditions are favourable to the origination of primitive forms of vital processes at the present time, and the reason that such forms do not originate now is that the elements required for their development are seized and assimilated by the already developed organisms. In regard to the possible existence of life in other parts of the universe, the same con- ditions of instability which are peculiar to the group of elements 624 NETO: F: [OcToBER 26, 1899 nitrogen, oxygen, carbon, and hydrogen at ordinary temperatures on our earth's surface may exist in other groups of elements at widely different temperatures, giving rise in parts of the universe, even of the most divetse characters, to developments of life whose variety and magnificence are beyond the utmost reach of our imagination. A PAPER, entitled ‘‘ Wanted, Plant Doctors,” is to be found in the current issue of the Contemporary Review, in which the importance of the subject of plant pathology is briefly dealt with. While giving credit to the workers at the British Museum, Kew, &c., for the attention they are paying to this branch of science, the writer of the paper shows how far behind America and Germany this country is in recognising the import- ance of the subject. He thinks, however, that this will not be always so; ‘‘a time must come when every agricultural district will have its plant doctor, and when specialists in animal para- sites, cryptogamic botany, and bacteriology will be consulted in difficult and obscure cases, just as the help of Harley Street is called in by medical practitioners. The practice of plant medi- cine is in its infancy; but with increased competition in the growth of cultivated crops, the farmer cannot afford to neglect any help that he can get in keeping the plants under his care in as high a state of health as possible.” ‘‘ What better use,” adds the writer, ‘‘ can be found for a philanthropist’s money than the founding of a school of practical plant pathology, for the investigation of the diseases which occur in Britain ?”’ In the October number of the Zoo/agzst the editor, Mr. W. L. Distant, continues his communication on mimicry. While referring only to a limited number of examples, he divides his subject primarily into demonstrated, suggested and disputed cases of mimicry ; adding a section on purposeless mimicry, and asecond devoted to active mimicry. Under the heading of sug- gested mimicry the curious resemblances between certain tree- shrews and squirrels, as well as that between the Cape hunting- dog and the spotted hyzna, are rightly included ; but it seems a little curious to find the East African Guereza monkey, whose coat has been shown by Dr. J. W. Gregory to present such a remarkable resemblance to the pendent lichens of the trees on which the animal lives, included in the same category. Under the heading of purposeless mimicry are included cases like the resemblance of the bee-orchis to the insect from which it takes its name; while active mimicry denotes those instances where insects or other creatures take special measures to avail themselves of their resemblance to other objects. THE same journal likewise contains a very suggestive paper by Mr. C. Oldham on the mode in which bats secure their insect prey. It has been observed that these animals, when walking, carry the tail curved downwards and forwards, so that the membrane connecting this organ with the hind legs forms a kind of pouch or bag. If a large insect be encountered the bat seizes it with a snatch, and slightly spreading its folded wings and pressing them on the ground in order to steady itself, brings its feet forwards so as to increase the capacity of the tail- pouch, into which, by bending its neck and thrusting its head beneath the body, it pushes the insect. Although the latter, especially if large, will often struggle violently, when once in the pouch from which it is subsequently extracted and devoured t but rarely escapes. It is assumed that the sime method of capture isemployed when on the wing ; and a correspondent of the author, who has observed the long-eared bat picking moths off sallows, states that ‘‘ the bat always hovers when taking off the moth, and bends up the tail so as to form a receptacle for the insect as it drops.” Mr. G. C. WuHippLe and Mr. D. D. Jackson reprint, from the Journal of the New England Water-works Association, NO. 1565, VOL. 60] a paper on Asfertonella formosa, a diatom which sometimes appears in great quantities in reservoirs of drinking water, imparting to it a geranium-like or fishy odour, from the pro- duction of a substance analogous to the essential oils. Its development is seasonal, appearing chiefly in spring and autumn, Its growth is greatly favoured by strong light ; and the most efficacious preventative appears to be the storage of the water in the dark. THE Director of the Botanical Garden at Buitenzorg, Java, has issued the first number of a Avw//etZn of the Botanical Institute, containing a history of the Institute down to the present time, a plan of the buildings and of the gardens, with a list of the plants grown in them, and a list of the official publications. Besides the special laboratory for workers from other countries, the Institute contains laboratories for agri- cultural chemistry, for phyto-pathology, for agricultural zoology, for pharmacology, and for the study of the coffee and tobacco plants. Pror. Davip G. FAIRCHILD gives, in the Botanical Gazette for September, an interesting account of a visit to Payta, in Peru, reputed to be the driest spot on the face of the globe. Payta is situated about 5° S. of the equator ona coast which has risen 40 feet within historic times. The average interval between two showers is seven years; when Mr. Barbour Lathrop and Prof. Fairchild visited it in February, there had recently been rain lasting from 10 p.m. one day till noon the next day, the first for eight years. There are frequent sea-fogs. The flora consists of about nine species; of these seven are annuals, the seeds of which must have remained dormant in the ground for eight years. Notwithstanding the scarcity of rain, the natives subsist by the growth of the long- rooted Peruvian cotton, which is able to maintain itself without rain for seven years in the dried-up river-bed, and yields profitable crops of the coloured short staple cotton, which is used as an adulterant for wool. THE Calendar, for the session 1899-1900, of the University College of North Wales has just been issued by J. E. Cornish, Manchester ; and the University Correspondence College Press has published its London University Guide for the same period. THE Bulletin of Miscellaneous Information (Botanical De- partment) for Trinidad, No. 20, July 1899) contains a report, by Mr. G. Massee, on the cacao pod disease, in which he states that, in addition to the well-known Phytophthora omnivora, a second parasitic fungus, Wectrza Baznez, sp. n., occurs on the diseased pods. WE have received from the Purdue University Agricultural Experiment Station at Lafayette, Indiana, a parcel of reports (Bulletins Nos. 71-79) on various subjects o! practical importance to agriculturists :—The San José and other scale insects ; field experiments with wheat; skim milk as food for young growing chicken, &c. Pror. EtmerR GaTes describes in the Sczentific American a number of pictures he has obtained of the electric discharge, by placing a photographic plate between the two poles of a ten-plate electrostatic machine. The illustrations accompanying the article are of much the same character as those given by Lord Armstrong in his elaborate work on ‘‘ Electric Movement in Air and Water,’ but they are on a smaller scale, and therefore less full of detail. A NEW edition—the fourth—of ‘‘Our Secret Friends and Foes,” by Prof. Percy Frankland, F.R.S., has been published by the S.P.C.K. The author has re-written the chapter which was added to the immediately preceding edition, and has added some of the latest results achieved in the study of bacterial OcTOBER 26, 1899] NATURE poisons, such as that of bubonic plague, and of some other poisons of a non-bacterial origin. Messrs. LONGMANS AND Co. have issued a new edition of Prof. Lloyd Morgan’s ‘‘ Animal Biology.” The book was originally published twelve years ago to meet the requirements of the Intermediate Science and Preliminary Scientific Examin- ations of the London University. The present edition has been revised, and some chapters re-written, to meet the requirements of the existing syllabus. Several illustrations now appear in the work for the first time. NEw editions of two well-known books of chemistry (Ostwald’s **Grundriss der Allgemeinen Chemie,” and Lothar Meyer’s ** Outlines of Theoretical Chemistry,” the latter translated by Profs. Bedson and Williams) have recently come to us from their publishers—Engelmann of Leipzig, and Longmans and Co The former is a third edition, and the latter a second, and an attempt has been made in each case to bring the work up to date. REFERENCES to practically every article and work on geo graphy published during the year 1896 will be found in the fifth volume of the ** Bibliotheca Geographica,” prepared by Dr. Otto Baschin for the Berlin Geographical Society, and just published by the firm of W. H. Kiihl. A comprehensive classification of subjects is adopted, and it is easy to find the works published in any branch of geography in 1896. In ad- tion, there is a complete index of authors. Students of geo- graphy know the work so well that no comment upon its thoroughness is necessary here. THE additions to the Zoological Society’s Gardens during the past week include a Green Monkey (Cercopithecus callitrichus) from West Africa, presented by Mr. G. P. Kinahan ; a Macaque Monkey (Aacacus cynomolgus) from India, presented by Mr. A. M. Burgess ; a Gambian Pouched Rat (Cricetomys gambianus), a Nilotic Trionyx (Zrzonyx truénguds) from Sierra Leone, pre- sented by Mr. Ernest E. Austen; a Red-footed Ground Squirrel (Xerus erythropus) from West Africa, presented by Mr. F. H. D. Negus; two Herring Gulls (Larus argentatus), British, presented by Mr. J. W. Edgar; a Melodious Jay Thrush (Leucodioptron canorum) from China, presented by Mrs. Currey ; a Spoonbill (Platalea leucorodia), a Kestrel (Tinnun- culus alaudarius), captured at sea, presented by Captain E. W. Burnett; a Green Turtle (Chelone viridis) from Ascension, presented by Mr. W. Hebden, C.E. ; a Chameleon (Chamaeleon vulgaris) from North Africa, presented by Mr. F. G. Ward; two Serrated Terrapins (Chrysemys scrifta) from North America, a Bennett’s Cassowary (Casuardus bennetti) from New Britain, a White Goshawk (4s¢ur novae-hollandiae), two Sacred Kingfishers (Haécyon sancta) from Australia, a Forsten’s Lori- keet (Zrichoglossus forsteni) from the Island of Sambawa, a Ring Ouzel (Zurdus torguatus), British, deposited ; a Crab- eating Raccoon (Procyon cancrivorus), two Short-eared Owls (Asio brachyotus) from South America, purchased. OUR ASTRONOMICAL COLUMN. HoLMEs’ Comer (1899 a). Ephemeris for 12h. Greenwich Mean Time. 1899. R.A Decl. h.m. s cage “ Oct. 26 2A5 7°04 +49 II 29°7 ime 643° 55°55. |... Te 2-6 28 A2VA3°32) nes 14 12°0 29 41.30'56 14 58:0 30 40 17°40 15 20°5 3r 39 3°95 15 196 Nov. 1 37 50°33 14 554 2 2 36 36°67 +49 14 8:0 NO. 1565. VOL. 60] Nova SaGirtaril.—Harvard College Observatory Circular, No, 46, gives the details of the position of Nova Sagittarii, discovered in April 1898, as obtained from micrometric measure- ment of enlargements from the plates, taken with the 8-inch Bache and 11-inch Draper telescopes, on which the star was photographed. Prof. Pickering finds that the accuracy obtain- able by this method is equal to that given by the best meridian circle observations. The mean position as determined is RAL = 18h. 56m. 12°83s. | DWecly—"— 13° 18012698 yereels OrBIT OF Eros.—In the Astronomische Nachrichten (Bd. 150, No. 3597), llerr Hans Osten, of Bremen, discusses the numerous observations of the new minor planet now available, and gives the two following provisional sets of elements for the orbit :-— Epoch of Nodal Passage, 1898 Oct. 1:0, Berlin Mean Time. 14. iit M = 238 38 33°627 238 39 44°636 @ = 137 9 24:77 177 39 21°05 8 =342 8 48°58 +» 303 31 53°37 Z= 30 42 32°105 man 10 49 33°99 G25 2A) es 12 52 18°33 w= 201557814 2015/°34326 log a= 0°1637380 STRASSBURG OBSERVATORY.—The annual publication com- piled under the supervision of Herr E. Becker, the director of the Imperial Observatory of the University of Strassburg, has re- cently been issued, containing the reductions of star observ- ations made during the period 1882-1888, together with miscel- laneous results to 1893. The observations made with the meridian circle, occupying 154 pages, are preceded by some twenty pages giving details of the determination of collimation, level, azimuth and other corrections. Following these are given the individual observations of the positions of 223 stars measured from 1882-1883, and of 1146 stars measured during the period 1884-1888. From these three catalogues are compiled, one of 254, one of 858, and one of 368 stars, the latter contain- ing corrections from Epoch 1880. Three appendices deal with heliometer measures of the partial solar eclipses of 1890, 1891 and 1893, the determination of the form the pivots of the meridian circle of the observatory, and the compilation of precession tables (both annual and secular) respectively. THE NERVE-WAVE (LA VIBRATION NERVEUSE). AS you told us, sir, two days ago in your admirable address, the century now drawing to an end is most honoured in the close union of men of science of all nations. If, owing to stupid prejudices and barbaric hate, nations are still separated by divisions which may lead them into fratricidal war, it falls to the men of science at least to set the example of concord, in order that by their teaching, based on reason, they may bring to all peace, sweet peace—the chimeera of the past, the hope of us all to-day, the reality of to-morrow. To this end nothing can be more effective than the great example of the British Association and the Association Francaise, who, within the space of a few days, are to meet twice as partners in their fertile work : to-morrow on English soil, in this hospitable town of Dover ; five days later on the soil of France, on the shores you can see from here, where you will find the same courteous and cordial welcome as our countrymen will receive on this side. Yet after these words of peace must come words of war—nay, its open declaration. Men of science have not the right to stay within the closed gates of their tower of ivory ; it behoves them also, even at the cost of vain popularity, to wrestle and to wrestle unceasingly for justice ; to form a grand international league, to turn the united forces of all generous minds against the common foe, the worst enemy of man: and this is ignorance. We must not value unduly the admirable conquests won by science in this century. Admirable as they are, they are yet nothing as com- pared to the great mystery beyond. Newton compared our science to that of a child, who should pick up a pebble on the 1 Evening Address delivered by Prof. Charles Richet on September 15, at fhe Bove Meeting of the British Association. Translated by Prof. Marcus artog. 626 NARGRE [OcTosBER 26, 1899 sea shore, and think he has penetrated the secrets of ocean. After all our searchings and all our efforts, to-day we can hardly say more. The shades that surround us are as deep as in the time of Newton; and in this universe, vast and obscure, at most scattered glimmers of light, few and far between, reach our straining eyes. We need all the co-operation of all men of science, of all nations, to dispel some of these shades. What madness it would be not to unite, not to walk hand in hand, but to strive apart ! The reward of this union will be above all price: the conquest of truth, the control of brute matter, the gift of a life less pre- carious and less painful to man, feeble man. And so you see what we should think of those self- styled patriots and nationalists, who speak of French science, English science, German science, as if science were not inter- national, and lifted high above our vain frontier limits. To the history of nerve-waves many workers of diverse countries have contributed their share; as with every great scientific problem, every country of the world has taken part in its solution. But before I go on, let me pray your indulgence for treating of so arid and so difficult a subject before you. Te *e The world around us presents itself in different aspects to the eyes of the student and of the layman. in them, and commonly defined by the impressions made on our senses. A given object is warm, light, electrified, heavy, and so forth; and every one thinks that heat, light, electricity, weight, are so many realities, distinct from the object itself. But the man of science conceives matters otherwise. For him this vast universe is formed of an indefinite ‘‘ something ” termed ««Energy,” and he knows that this force may have different mani- festations in motions of diverse kinds. Weare almost justified in saying that ‘‘ Energy is one” ; that its aspects appear to our senses so different because the various movements of this energy have not all the same qualities. They differ in number, in frequency, in rapidity, in form; and according to these different modalities which we perceive, and to their results, we have heat, light, electricity, attraction. The movements of this energy are all transmitted in the same way, by wave-motion—“ undulation ” or “‘ vibration,”’ as we call it; and the physicists, by wonderful research, in which the highest mathematics must be utilised, have succeeded in de- termining the forms of certain kinds of these waves. And even those motions of energy which we do not so well understand, we are justified, by what we do know, in regarding also as wave- motions or undulations. I need not dwell on this phenomenon of undulation or vibra- tion. We all know the simple case when a pebble is dropped into still water ; and the surface, which was smooth as a mirror, now shows a series of disturbances propagated in ever-widening concentric circles. In each oscillation we see two periods: in the one the water recedes from the primitive plane of the mirror, in the other it comes back to it again. The former is the ferzod of departure, the latter that of veturn. So, if we hit a hanging weight, a pendulum, the shock at once removes it from its position of equilibrium, and it recedes further from it (period of departure) ; then it comes back again to its starting point (period of return). What I have called undulation and vibration are two names for the same _phe- nomenon, of the greatest diversity in form, but essentually due to the wave-motion of a fluid. Though, if you will, this fluid, the ether, be of very hypothetical character, we will take it for granted here, and say that heat, light, electricity, gravitation, are all wave-motions of the ether. Consequently, the outer world in its infinite diversity of aspect, in form and in colour, is the sum total of the various vibrations of force. These vibrations, most diverse in character and in intensity, act upon the living organism, and produce sensations therein. Now it is probable that, as I shall try to show you directly, these vibrations of the outer world only act on our senses by evoking within us another kind of vibration, to which are due sensation and perception. Thus the nerve- wave is revealed to us as the goal and the final term of the vibrations of the external world. Were there no nerve-wave, though, no doubt, all these external vibrations would still exist, still they could produce no effect on us. In virtue of its own proper vibrations, the living being becomes the microcosm, the recipient of the diverse vibrations of the macrocosm, the universe : NO. 1565, VOL. 60] The layman sees } external objects, endowed with properties apparently inherent: by these vibrations only is the universe accessible to our under- standing. Thus you see what of interest lies in the study of this nervous vibration, since through it the outer world is known to us, and through it we have the power to act on the outer world. Il. This study is no new one; I should trespass beyond the limits of your courteous attention were I to try and recount all the classical facts that are well known at present. Yet, that you may understand the new facts I am coming to presently, I shall have to give youa short summary of some of these classical facts ; and I hope that despite their being so well known, they will not be devoid of interest to you. The nervous system is made up of distinct elements, each con- sisting ofa cell, with very long fibrous outgrowths. These cells. with part of their outgrowths are compacted into the central nervous system, while the rest of the outgrowths are produced into strands, the peripheral nerves. An elaborate microscopical analysis of the last few years, largely due to Golgi and to Ramon y Cajal, have shown that the total number of processes is countless. Each cell sends forth at least one outgrowth, the axzs cylinder, which remains unbranched except at its very termin- ation ; while the others, like the branching roots of a forest tree, spread out in all directions, so that they interlace with those of its neighbours. Thus all the nerve-cells are in communication ; the disturbance of one may affect all. And this disturbance may,be propagated far and wide ; for in the peripheral nerves pass out the axis-cylinders, which separate ultimately and get up to the very tips of the limbs, to the skin, the entrails, the muscles, and the glands. Think of the whole surface of the skin as provided with little nerve apparatuses, all capable of vibration and of transmitting their undulations through the sensory nerve-fibrés to the nerve-centres; of the nerve- centres as possessing processes like the sensory fibres, whereby to transmit their orders to the muscular and glandular organs; and you will be able to realise the part played by the nerves in the life of the organism. It is a vast telegraphic apparatus, to receive, by its sensory receptive mechanism, all impressions from without, and to transmit, by its transmitting mechanism, corresponding messages to the organs. of motion, the muscles. And, since all the nerve-cells are, moreover, in communication with one another, and since every living cell is in relation with nerves, we may sum up the rela- tions of the living organism in this general formula : through the nervous system, any one living cell reverberates in every other cell, and is reverberated to by every other cell. Thus the living organism that possesses a nervous system is no mere aggregate of cells; it isan zvdivédual, all the parts of which co-operate for the common weal. The nerve-cell, together with its prolongations, has received the name of ‘‘ neuron”; we can conceive that by the inter- relations of all its neurons the living organism may be regarded as one gigantic neuron, sensible to all stimulations at the periphery, and answering them by stimulations of the motor apparatus, which are translated into acts of motion or of secre- tion. This sensibility and its motor response are linked by a phenomenon which we shall call for the present the ‘‘nerve- vibration ” or ‘‘ nerve-wave.” How far is this name justified ? This is the question that we have to deal with. III. Let us for the moment make the assumption (which is not quite exact) that the phenomena are identical in the peripheral nerves and in the central nervous centre, and that what applies to the one will also apply to the other. We may, at least, accept them as analogous, since the axis- cylinder of the peripheral nerve is an expansion of the proto- plasm of the nerve-cell. True, the reactions of the peripheral and of the central nerve tissue are not identical; but their differences are probably in accessories, not in essentials. We may, therefore, boldly accept their analogy, if not their identity ; and we are justified in applying to the one the truth that we learn of the other. The pace at which an impulse travels along a nerve is well known since 1850. Strange to say, just two years before, a great physiologist, one to whom the science is indebted for some of its grandest advances, Johannes Miiller, declared that it was impossible for us to determine the speed of nervous transmission—an affirmation as imprudent as are all affirmations which proscribe formal conclusions to the science of the future. OcrToBER 26, 1899] NATURE 627 Well,.as I say, just two years after this unfortunate prophecy of Johannes Miiller, Helmholtz ascertained that, if you deter- mine the time of response by stimulating a nerve at a given point, you can determine the rate of transmission by stimulating the same nerve at a measured distance, say a decimetre, above that point; for, as in this case, the response will be delayed, the period of delay measures the rate the nerve impulse has taken to travel over ten centimetres. Since then countless de- terminations have been made of the speed of the nerve-current. It has been found to vary with the temperature and with the character of the nerve stimulated ; it is less rapid in the nerve- centres than in the peripheral nerves, less in cold-blooded than in homeceothermic (or so-called warm-blooded) animals. But it never differs much from thirty metres per second. Moreover, this nerve current has been found to be always transmitted in both directions from the point of stimulation. I will not dwell on the exceedingly technical proof of this law, but merely recall the fact that whether the nerve stimulated be motor or sensory, the nerve current travels both ways along it, both towards the periphery (skin, muscle, &c., as the case may be) and towards the central nervous system. A most important fact is that an electrical disturbance ac- companies every stimulation of a nerve. If in the undisturbed condition we place the poles of a circuit with an interposed galvanometer at two points of a nerve (one on its surface, the other on a cut end), to ascertain its electric condition, we find that there is an electric tension between them, that there exists in the nerve a certain current. If we then stimulate the nerve, the current is seen to be reversed, or, as we say, undergoes a “‘negative variation,” and the rate at which this change is transmitted is sensibly the same as that of the nerve-wave. Matteucci, Du Bois Reymond, Bernstein, Waller have studied all the complex details of this process; so that it now ranks among the best known phenomena in physiology. We ask :—Are there, concurrent with this electric variation, modifications in the chemical and thermic condition of the nerve or nerve-centre? Yes, in all probability ; but the answer is not certain. Schiff thought that by stimulating the retina of the pigeon he induced a change in the temperature of the brain. Mosso also thought he could find localised areas of higher temperature in the brain after stimulating certain points; but the elevation of temperature is, to say the least, of low in- tensity and difficult to determine. In this rapid sketch, the last law I have to formulate is the law of the integrity of the organ. The physical and mechanical union may be maintained; but if its organic continuity be severed as by a cut, even when the two ends are joined up, the nerve-current is no longer transmitted. IV. Several hypotheses may be put forth as to the nature of this phenomenon. Formerly, when words were accepted in place of facts, it was said that there was a transference of ‘‘ animal spirits” (a con- ception due to Descartes); this was the current expression in the sixteenth, seventeenth and eighteenth centuries. A curious apparent confirmation was found in Richard Lower’s experiment: he tied a nerve, and saw that it swelled above the seat of lig- ature ; this, said he, was the accumulation of the animal spirit, arrested by the tightened thread. The experiment was a per- fectly valid one; and you see that from it it was possible to deduce conclusions that were perfectly false. The swelling was due to the increase of blood pressure and to inflammation. We may drop this old hypothesis of ‘‘ animal spirits,” and pass to four theories put forward to explain the nature of the nerve-current. (1) Mechanical Hypothests.—lIf, as is probable, the semi-fluid protoplasm of the nerve-cell and its prolongations form one con- tinuous whole, it follows that a mechanical disturbance of this liquid mass will be propagated to a distance along the whole length. Suppose a capillary tube filled with mercury; a dis- turbance of the mercury will be propagated the length of the tube, so that at the far end we perceive a vibration started from the opposite end. In this case the nerve-wave would be the molecular disturbance of a liquid enclosed in a capillary tube. This hypothesis would afford a fair explanation of the elec- trical phenomena involved ; for we know that the friction of a fluid in a capillary tube produces electricity. However, this mechanical explanation presents certain difficulties, for in a capillary tube the narrower its calibre the more rapidly the s NO. 1565, VOL. 60] vibration is damped ; consequently, it is hard to conceive that a vibration could be transmitted so as to be appreciable at the far end of a tube one or two metres long. It is true that we can form no supposition as to the absolute measurement of such perturbation ; and perhaps almost infinitesimally small forces are adequate. On the other hand, the electric disturbance that accompanies the nerve-wave does not lose intensity as it travels : on the con- trary, Pfliiger and other physiologists declare that it grows like an avalanche. Hence, taking all considerations into account, the nerve-wave is a phenomenon other than a mechanical vibratory molecular disturbance of the semi-fluid protoplasm. (2) Chemical Hypothests,—The transmission of the nerve- wave along a nerve has been compared to the explosion of a train of powder, or of mixed gases in a tube; and this you know is transmitted relatively slowly, nay, very slowly if the tube be of capillary dimensions. If, say, an explosive mixture of oxygen and hydrogen be contained in a very narrow tube, and a flame or spark applied at one end, the combustion will not be instantaneous, but will pass as a wave along the tube, and that a very slow wave, if the tube be narrow. What at first sight would give some plausibility to this hypo- thesis is the fact that a very feeble stimulus may call forth a very strong response. Take the amount of energy received by a surface of r sq. cm. from a candle 300 metres distant; it is I/10,000 millions of the total light-giving energy of the candle, a quantity whose absolute value is in one sense a negligible quantity, but which is adequate to give a sensory stimulus to the retina, The retina must be supposed to contain a quantity of accumulated energy susceptible of explosive liberation, so that the amount freed would be far in excess of the energy of the stimulus. But there is one very serious objection to this hypothesis ; it demands that the explosive tissue should be reconstituted afresh immediately after each explosion. It is not easy to see how the moment after the explosion, in the hundredth of a second, the nervous substance could be reconstituted afresh. Though serious, the objection is not irrefutable, for we know too little of the speed or slowness of the chemical changes of the organism to use this as an argument against any theory whatever. (3) Electrolytec Hypothests.—Certain chemical changes are characterised by their allowing of an immediate reconstruction after their occurrence, such are the phenomena of electrolysis. When a current passes through a saline solution, it is believed that, as it passes along, the salt is decomposed from place to place, and immediately reconstituted as soon as the current has passed, The passage of the electrolytic current is sometimes exceedingly slow. There is nothing to prevent our accepting some such explanation of the nerve-wave ; it has the advantage that it can be brought more or less into harmony with the chemical and the electrical hypothesis, and can indeed reconcile them. (4) Electric Hypothesis.—This supposes that an electrical current passes along a peculiar form of conductor—the nerve. The chief objection that has been urged, in the extreme slow- ness of the nerve-wave—30 metres per second—as against 700 million metres, the alleged rate of electricity. But this omits to take account of the fact that electricity travels at this speed in good conductors only. Electricity passes along a conducting wire, ten thousand, a hundred thousand, times as fastas along a badly conducting tube; it is only reasonable to admit that the transport of electricity may be enormously retarded in a capillary tube filled with a very bad conductor. It has also been urged that, since different nerves can transmit very different sensations simultaneously to the different parts of the nervous system, there should be a blurring and confusion from the imperfect in- sulation of the tubes if it were electricity that they conducted. “* How, for instance,” we are asked, ‘‘ could nerve-cells of the cord and the brain communicate their electrical disturbances in narrowly localised groups with that extraordinary precision, without the neighbouring cells feeling the effect ?” We do not attach much weight to this objection because, in the first place, the axis cylinders have an insulating covering of myeline, as have also the cells of the brain; and again, in electric fishes, electric shocks one hundred thousand-fold as strong pass between certain organs without the rest being at all affected, so perfect is the insulation. ‘ : Thus the hypothesis that the nerve-wave is an electric phe- nomenon is fairly satisfactory, especially if we admit that it resembles electrolytic action, 628 NATURE [OcToBER 26, 1899 Certainly we must allow for the unforeseen ; we must recognise the possibility that, perchance at no very distant date, we may receive the formal demonstration of fundamental differences be- tween electrical and nervous vibrations, and have to admit that the latter possess special characters which differentiate them from all known classes of vibrations. Vv. I now come to a different order of facts, on which I will speak more fully, for I have to deal with my own researches, some, indeed, as yet unpublished. These I carried on in collaboration with M. André Broca ; they are, I think, of a character likely to shed light on some of the conditions of the nerve-wave. True, they tell us nothing of the actual nature of nerve-vibration ; but they will allow us to deduce the form of the nerve-wave. Our experiments were made on the nerve-centres, not on the peripheral nerves ; as a matter of fact, we believe that the laws | which we have discovered for the one will apply to the other, and Charpentier’s recent and most ingenious researches confirm this assimilation. We must go back to the very definition of a vibration. We have seen that it is a movement of oscillation, an object is removed from a position of equilibrium and comes back to it | again. Such is a szmple oscillation ; in a complete wave, after returning to the position of equilibrium from the furthest point, it passes that position and only returns after a certain traverse in the opposite direction. If we call the first simple oscillation from the position of, equilibrium the Josztive phase, the second oscillation is regarded as the megative phase of the complete wave. Now the phe- nomenon is no simple one; the return to equilibrium is not Typed. Fic. 1. | | durable, and if no new condition intervene the vibration will continue. Were there no friction or resistance the vibration would persist indefinitely ; for there is no reason for the motion | to stop, and the pendulum, to take the very simplest case, | would never return to rest at its original position of stable equilibrium. To stop the vibration there must be some deadening or damping process. | Physicists have studied the modes of damping, and find that | they are divided into three types. | Type a is that of a pendulum, a vibrating string, or the waves | of liquid when a stone enters the water. A series of complete | waves follow with smaller and smaller oscillations, and the | vibration dies out by the gradual decrease of the waves— | secondary, tertiary, &c.—which followed the primary wave. This type of damping is, as we have said, due to the resistance | of the medium consuming part of the energy ; for, theoretically, a vibration once started would never stop. You are familiar with the fact that a pendulum continues to swing much longer | in vacuo than in the air, and I need not dwell further on this | point (Fig. 1). Type 8 shows a very different character in its damping. | After the pendulum has completed its first phase and passed | the point of equilibrium, it meets a certain obstacle to its return point ; it only swings back again very slowly thereto, and on reaching it it cannot pass beyond it. Indeed, from diverse theoretical considerations it may be proved that it never returns absolutely to the point of equilibrium; it approaches it in- definitely without ever reaching it; in short, ABA’ is an asymptotic curve of which Aa’ is the asymptote. Later on we | shall see what conclusions may be drawn from this as to the nature of the nerve-wave. Suffice it now to demonstrate the form of the wave with this type of damping. Practically, stable | equilibrium is reached sooner than by type a: indeed, this is | the type of damping used in the transmission of signals by sub- NO. 1565, VOL. 60] marine cables ; where it is necessary to prevent each signal from producing a whole series of swings of the galvanometer needle, and to obtain as rapidly as possible its return to equilibrium and rest (Fig. 2). Type 7 remains to be described: here the pendulum, after being moved from the point of equilibrium, returns only very slowly to that position ; this it does, for example, when hang- ing in a very dense medium. In this type of damping, as in B, there are no consecutive secondary and tertiary vibrations ; nay, more, the damping is here so complete that there is no negative phase, only a simple oscillation, This curve is also asymptotic, and the return never reaches the primitive state of equilibrium (Fig. 3). We see at once that the form of the wave is determined in each case by the type of its damping, and our experiments have B Fic. 2. enabled us to determine the character of the damping of the nerve-wave. We might have set type a aside @ przorz; it would have been unreasonable to suppose it. If to wave I succeeded waves 2, 3, 4, &c., a single stimulus would produce a whole series of responses ; now this is not the case with the nerve. Hence the damping must be on the type of 8 or of y. But obvious as these considerations are when once stated, we did not reach them @ frtor¢; it required actual experience to enlighten us ; so true is it that in science, at least in physio- logical science, experiment is more fertile than dialectic. VI. The following were the methods by which we determined the form of the nerve-wave. I will not describe our research in order of time ; I shall only select some of the simplest, the most demonstrative, experiments. We know that but rarely are the earlier experiments one or the other; they are complex and Type ry. A Fic. 3. slow, and it is only by degrees that one learns how to simplify them and make them direct. A dog is anzesthetised by the injection of a sufficient dose of chloralose into the veins (o°r gramme to the kilo. of live weight), and electrodes are applied to the surface of its head. We can now observe the effects of an electric stimulus on the cerebral cortex under excellent conditions. The electrodes can be fixed immovably, so that the same part of the cortex is always stimulated ; and the effects of the stimulus are always localised in the same muscles. If we repeat the same electric stimulus, supplied by a secondary current from accumulators, always of the same suitable intensity, we find that each successive electric shock, repeated at intervals of one second, calls forth a regular and equal muscular contraction in response. This regularity is complete, and if the conditions of circulation and respiration are kept satisfactory for one, two, or even three hours, we have a OcToBER 26, 1899] NATURE 629 series of regular contractions which are easy to register. But when we quicken up the succession of the stimuli, there comes atime when the responsive contractions lose their regularity : a normal contraction is followed by a small one, a large one by a small one, and soon. Thus we can determine at what rate of intermission of the successive stimulations their responses lose their regularity: we find that when the intervals between the induction shocks are less than the tenth of a second, at the normal temperature of the body (39° C. for the dog) the con- tractions are no longer regular. Matters now go on just as if, after the large normal contraction, there were a refractory period, during which the excitability of the nervous system is lowered. Marey, in his beautiful researches on the heart, had previously showed that after a contraction of the heart there is a short refractory period during which it is not excitable. So, after the stimulation of the brain, a period not exceeding 1/10” inter- venes during which it is not excitable, a refractory period. Whatever be the temperature of the animal under experiment, we always find this refractory period, which, however, becomes easier to measure when the temperature falls, for then it lengthens out enormously. It is 0-1” at 39°C. ; e718" at 35° C.; and if we chill the dog greatly, to 30° C., it rises to 0°6”. Hence it is advantageous to chill warm-blooded animals for the purpose of these observations. It is noteworthy that this refractory period can be demon- strated otherwise than by electrical stimuli; mechanical shocks will also serve the purpose. If we poison a dog with chloralose, it becomes extremely sensitive to every mechanical disturbance. The least jolt of the table on which it lies makes it start, and though insensible, and not susceptible to pain, it responds to every jolt by a start. We can register these starts; and if, working with a dog cooled to 30°, we repeat the jars at intervals of less than half a second, the starts lose their regularity. Under these conditions a big start is followed by a small one, and wice versd, though the jolts of the table are quite equal. In successful experiments we may even find the second shock absent ; so that if the times of the successive jolts be noted as a a, a’, a’, at, &c., we only get responsive shocks at a, a2, a‘, &c. The physicists have given the mathematical and mechanical explanation of this phenomenon, which they call the ‘* syz- chronisation of the oscillators”; it has recently formed the subject of an important memoir by Cornu, which, however, I cannot de- scribe even in abstract here. Suffice it to say that these refractory intervals presuppose the existence of a refractory period, of a negative phase in the nerve-wave. The synchronisation of the nervous oscillation with that of the stimulus can only be explained by the assumption of the vibra- tion of an apparatus (the nervous apparatus) possessing a proper period of its own, and with which we regulate and adjust the proper period of a second apparatus (the stimulating apparatus). Thus, by this method we have succeeded in determining the duration of the nerve-wave ; and we may state that this is 1/10’, an exceedingly slow rate as compared with electric or luminous vibrations, whose period is measured in 1I-one thousand millionths or billionths of 1”. We can also determine the form of the wave, and we find it approximate to our type 8. If we consider the period of o'1” which elapses between the stimulus and the completion of the nerve-wave, we find that it may be divided into two periods : (A) in the first part a second simulus will augment the effect ; it is the “* phase of summation” or positive phase of the wave. (B) in the second period the stimulus produces a decreased effect ; this is the ** phase of subtraction” or negative phase. Now the phase of summation is very small, scarcely more than 0°01’, while the phase of subtraction is very long, nearly 0°09” ; but I must not go into more detailon this point, lest I should enter on matters too strictly technical, which I prefer to avoid. VIL. In cold-blooded animals the phenomena are quite different ; and recent experiments have shown us how imprudent it would have been to generalise too hastily. If, indeed, we repeat the experiment on a tortoise, we find results apparently contra- dictory of those I have just related to you. A stimulus following another always appears to produce a stronger response than its predecessor. There is no refractory period, there ts a summation phase all the time. Of course I mean that the stimuli must not NO. 1565, VOL. 60] Jlickering ; that is, the images are becoming confused. be too far apart; if the interval exceeds 2”, two successive stimulations of the brain call forth equal contractions. But with intervals of less than 2” summation phenomena are always observed, the more marked as the interval between successive stimuli is decreased. Finally, as I say, there is no refractory period. Hence we may conclude that in cold-blooded animals (at least in the tortoise) the nerve-wave has a different form from that of the dog ; after the displacement from the primitive position of equilibrium there is only a slow and gradual return, without any such backward oscillation as explains the negative phase in the dog. This form of wave we have described under the third type of damping (type y) (Fig. 3). This type of wave is exceedingly slow; if the tortoise be chilled by the use of suitable stimuli, we can estimate its duration at 2”. But with normal animals at 15° C. the period may perhaps be taken as 1’’. This difference of tenfold is not surprising ; there was no ante- cedent improbability in conceiving that the nervous phenomena of a tortoise are ten times as slow as those of a dog. VIII. The fact that the nerve-wave lasts one-tenth of a second in the dog, as it probably does approximately in man, opens up a field of interesting considerations which confirm the results of direct experimental physiological observation. If the nerve-wave lasts 1/10’, it follows that two nerve-waves cannot remain completely dissociated when they follow at shorter intervals than this. Suppose that a stimulus of light calls forth a nervous reaction, a sensation ; this reaction, this sensation, will last at least one-tenth of a second ; and consequently when a fresh stimulus follows on the first, its sensory response will not be clearly distinct unlessjthis interval at least separates the two. If they follow more closely, they will blend together. Well, a classical and well-known experiment tells us that we cannot receive more than ten or eleven distinct retinal sens- ations in a second. At eleven per second, we already experience This, the persistence of retinal images, is the familiar principle of the cinematoscope, which has latterly received such elegant popular applications on a large scale. No such exact studies have been made on the confusion of acoustic or tactile stimuli. But the very remarkable and con- cordant results of retinal sensation are enough to prove that the cerebral vibration consequent on a stimulation of the retina has a period of 1/10”. If we turn to the case of a voluntary movement, determined also by a cerebral nerve-wave, we find the same figure. Schafer in 1886 determined that distinct successive muscular con- tractions, voluntary or called forth (as reflexes) by electrical stimuli, very rarely exceeded 11-12 per second. Herringham found a frequency of 9-12 in pathological tremors. In the case of shivering from cold, I have determined frequencies of 10, II, 12, 13 per second. Griffiths determined a frequency of 10 for the muscles of the thumb, and 14 for those of the arm. The Swedish physiologist, Loven, found that the electric oscillations of the cord determined by very frequent stimuli were only 8-10 per second. Yet we know that if muscles be stimulated directly by rapidly alternating currents, they will contract with much greater fre- quency. The numerous physiologists who have studied the subject are agreed that we may thus determine as many as thirty or forty muscular contractions per second. If then we can only produce some ten voluntary contractions in the time, the cause lies, not in the muscles, but in the cerebral apparatus, which cannot vibrate more rapidly. Its period is o'r"; it can only vibrate ten times in a second—can only order ten distinct voluntary movements of the same muscle in a second. It is not that the muscle cannot obey, but that the central nervous system cannot give its orders at a greater speed. Now I will give you an experiment that you can all try for yourselves, which proves most clearly that the vibration of the nerve-centres determining a psychological phenomenon lasts about one-tenth of a second. When I thought over the various modes of obtaining a very rapid muscular motion, it occurred to me that perhaps the best was the articulation of some sentence pronounced with the greatest possible rapidity. We may admit that every syllable articulated represents a distinct muscular contraction, and consequently a distinct effort of the will. On trying what was the greatest speed of articulation, I found it 630 was eleven syllables a second; and, indeed, at this speed all the syllables were not perfectly articulated. J : This experiment has no particular interest in itself, for it only confirms the results of Schafer, Lovén and Griffiths, that repeated voluntary muscular actions have a speed of some ten or twelve per second. But, if we modify it slightly, its bearings are much wider. If instead of voca//y articulating the syllables, we ¢4z7zk them and articulate them only mevdadly, we exclude muscular action from any share in the process, and the rapidity of the mental articu- lation will be the index of the cerebral rhythm, not the muscular, Well, I found, as any of you can do with the help of a good seconds watch, that the mental articulation gives exactly the same figure as the vocal; that is, ten or eleven syllables per second, We come to the interesting and relatively unforeseen conclusion that the cerebral phenomena of feeling (in the retina), volition (on the muscles), and thought (in mental articulation) cannot be repeated faster than twelve per second, and that they last about one-eleventh, or in round numbers one-tenth, of a second ; the isolated sensation, the isolated act of will, the isolated intel- lectual process, have all the same minimum duration. Placing this result next to our determination of the period of the nerve-wave, we conclude that there is here more than a mere coincidence ;iit is an @ fosterzort proof of our hypothesis as to the period of the nerve-wave. From the psychological point of view this leads us to very important deductions. Of course we can conceive the second to be divided into hundredths, millionths, billionths ; but these divisions have no relation to our direct consciousness. Our consciousness can only perceive much longer intervals. Our cerebral organisation determines narrow limits for our appre- ciation of time. We may therefore define the psychological unzt of time, the irreducible unit, as that minimum duration of time which zs appreciable to our intelligence. This is, indeed, suscep- tible of further theoretical subdivision ; but such subdivisions correspond to no real mental image. We may say, in other words, that the minimum time which our consciousness can directly apprehend is, in round numbers, one-tenth of a second. “* Swift as thought” is an everyday phrase; but you see thought is not very swift, after all, if we compare it to the enormous frequency of the vibrations of light and electricity. Sir William Crookes, one of your most illustrious presidents, spoke of the relativity of our knowledge in his recent address ; he alluded to the cruel imperfections of our animal nature. For us there exists no time-interval shorter than one-tenth of a second; and yet during this short interval, within which our gross intellectual apparatus cannot penetrate, who knows what sequences of phenomena may go on, which we could perceive if our nervous system had a shorter period of vibration ? Then would phenomena which we perceive as continuous reveal their true character of discontinuity ; those molecular vibrations which to us do not appear as vibrations would take on their real aspects. In a word, our time-unit, which is so different from the units of many phenomena of matter, makes us live in one perpetual illusion. One more point I wish to touch upon is interesting in many respects. Let us come back to the diagram I gave you above to show the mode of damping of the nerve-wave. I told you that the original level is never regained when the system is damped toa position of rest ; it approaches the level indefinitely but never reaches it. Practically speaking, equilibrium is reached at the end of the tenth of a second; physically and physiologically speaking, everything is set in order ; the nerve- wave is ended, and the return to equilibrium is total. But if we deal with infinitesimal quantities this return is not complete ; so that if we imagine an apparatus capable of appreciating infinitesimal quantities, it would show that, as the mathematical theory predicts, the return to equilibrium is never complete or absolute. Well ! we may fairly suppose that consciousness is alive to this infinitely small quantity, and that the impossibility of the complete return to the primitive equilibrium accounts for the strange phenomenon, unknown in the inorganic world, which we call Memory. After a nerve-wave, the neuron is no longer in the same state as before ; it retains the memory of the wave, and this makes it now other than what it was. I pronounce the vowel ‘* A”; one-tenth of a second later I can pronounce sone other vowel, for my nervous system has returned to equilibrium ; but this NO. 1565, VOL. 60] NATURE [OcToBER 26, 1899 return, however, is not complete, for the memory of the ‘*A”’ which I pronounced persists, and will persist indefinitely. The primitive condition will never recur, whatever happens. In time the memory of the vowel ‘‘ A” will gradually fade, but it will never be effaced. A nerve-wave of the brain is never completely extinguished. The fact is that we are here on the confines of two totally distinct worlds: the world of physics and the world of psych- ology. What is infinitesimally small in the physical world may possibly be infinitely great in the psychological world. The residues of nerve-waves, the asymptotic prolongations of curves, may be neglected by the physiologist and the physicist; they are not negligible to consciousness. Consciousness distinguishes them from the strong vibrations actually going on, which it recognises as ‘‘ the present” ; but the waves that are passed still exist for consciousness, never perhaps to be annihilated. Assuredly this is but an hypothesis, perhaps an analogy, a comparison, rather than an hypothesis; but it is none the less interesting to note how far the physiological theory of the damping of the nerve-wave is in agreement with the grand psychological fact of memory, which it is scarcely possible to explain in any other way. IX. Thus the nerve-wave in its form and period, and in the mode of its damping, is comparable with the various waves of the unbounded universe in which we live, move and have our being. But this resemblance must not lead us away from the recognition of the abyss that separates the nerve-wave from all the other phenomena within our reach. The vibrations of the forces scattered about us are—at least with the greatest prob- ability—blind phenomena, which know not themselves, which are the slaves of irresistible fatality. The nerve-wave, on the contrary, knows and judges itself; it is self-knowing or self- conscious; it can distinguish itself from the world which surrounds it and shakes it. Since it possesses intelligence—for intelligence and conscious- ness are synonymous terms—it is susceptible of perfectibility ; it is capable of right reasoning and of wrong reasoning ; it can attain a moral ideal forbidden to those brute forces which follow their fated course ; it can conceive the idea of truth and justice when it is a question of defending the innocent, of establishing brotherhood among men. Consciousness, intelligence, the making for higher perfection— these are characters that have nought in common with the char- acters of other waves ; they seem to be phenomena of another, a higher order. This vibration, whose physical conditions we have studied, enters into the domain of morals ; and this fact establishes its essential difference from all other vibrations. Assuredly the prodigiously rapid and regular undulations of light, and of electricity, appeal right justly to our admiration ; but nothing is so admirable as this disturbance of the nerve-cell, which is self-knowing, self-judging, self-transforming, which strives to amend itself, and which from the stimuli which strike it can deduce some of the laws ruling the vast universe distinct from it. The nerve-wave of man—himself the last result of evolution—is the most perfect term of the things and of the beings which it is given to us to know. Vast as is the world, mighty as are the fires of the infinite stars, the intelligence of man is of a higher order than these ; and I would fain exclaim with the great philosopher, Immanuel Kant : ‘‘ More than the starry heaven above my head, one thing fills me with admiration: the moral law in the heart of man.” ZOOLOGY AT THE BRITISH ASSOCIATION. @ the opening day (Thursday) only the President’s address was taken, and the Section then adjourned with the object of hearing addresses in other Sections which were of biological interest. The total number of papers brought before the Section this year was not as large as usual, but they extended over a wide range of zoological subject-matter, as the following outline programme shows —— Friday morning, morphological papers; Friday afternoon, papers on entomology and mimicry ; Saturday, marine biology ; Monday, morphology, &c.; Tuesday, papers on sea-fishery questions. The usual reports upon investigations in progress were also submitted. OcToBER 26, 1899] WAT URE 631 The morphological papers on Friday were as follows :— (1) J. J. Lister, on Astrosclera willeyana, the type of a new family of calcareous sponges. This remarkable new sponge was brought home by Dr. A. Willey from Lifu in the Loyalty Islands. It has a continuous calcareous skeleton formed by the union of numerous polyhedral spicules to form a branched mass, between which run the soft parts with the system of canals. There are very minute ciliated chambers, and the ciliated cells do not appear to have the usual collars. (2) Prof. Johnson Symington, on the morphology of the cartilages of the monotreme larynx. The thyroid cartilage of the monotremes (Ornithorhynchus and Echidna) agrees with that of the higher mammals in consisting of a single cartilaginous mass, but differs in the details and relations of its anterior and posterior cornua. Both the ontogeny and the phylogeny of the mammalian epiglottis support the view that it is a single median structure, and not, as Gegenbaur supposed, the result of fusion of two lateral elements. (3) N. Bishop Harman, the palpebral and oculo-motor ap- paratus in fishes. Seventy species of fishes were examined. The simplicity or complexity were not found to agree with differentiation in phylogeny, nor with any scheme of classification, nor in relation to habitat. The source of the complex muscu- lature of the eyelids of Selachians was traced to the branchial musculature of the spiracle, and this was further shown by the inverse ratio existing between the condition of spiracle and nictitating membrane. In those fish in which the latter is at its highest development the spiracle is absent, and wzce versd. The condition of the orbital sac, of the supporting rod of cartilage, of the eye-muscles, and of other neighbouring structures in the eyes of various groups of fishes was discussed. (4) Prof. R. J. Anderson, on the pelvic symphysial bone of the Indian elephant ; and a few notes on rhythmic motion. (5) C. Dawson and S. A. Woodhead, on the crystallisation of beeswax, and its influence on the formation of the cells of bees. On Saturday, when some of the zoologists from the French Association visited the Section, a few papers on marine biology likely to prove interesting for joint discussion were taken. Mr. W. Garstang brought forward a first report on the periodic in- vestigation of the plankton and physical conditions of the English Channel during 1899. These investigations have been carried out at regular quarterly intervals during the year, from a steam-tug ; and the observations were made at certain fixed localities along lines between Plymouth and Ushant,. from Ushant towards the 100 fms. line, and off the entrance to the Channel. Observations of the water temperature (with deep- sea reversing thermometers) at various depths, and of the salinity (with Mill’s water-bottle) of the water were taken ; and collections of plankton were made with an effective closing tow-net specially devised by Mr. Garstang to replace the pump and hose method, which had proved unsatisfactory. This new net, and also that of Dr. C. G. J. Peterson for the quantitative estimation of plankton, were on exhibition and with the rest of the apparatus were shown working. Mr. Garstang’s investiga- tions in the Channel are not yet completed, and two further series of observations are still to be made. The record so obtained will be of high value in both marine biological and hydrographical inquiry. Prof. Lankester and others took part in the discussion, and one of the visitors, Baron Jules de Guerne, explained the somewhat similar observations he had been making from the Prince of Monaco’s yacht Princesse Alice, and described the closing nets he employed. The reports upon the Naples and Plymouth biological stations were also submitted. On Monday the following papers were taken :— (1) J. Graham Kerr, the development of Lepidoszven para- doxa ; and a note on the hypothesis of the origin of the verte- brate paired limbs. Mr. Kerr had been sent by the University of Cambridge with an expedition in search of Lefidoszven to the rivers and swamps of Gran Chaco in Paraguay ; and he gave an interesting summary of the life-history of this important type. (2) Dr. J. F. Gemmill, on negative evidence regarding the influence of nutrition in determining sex. Dr. Gemmill shows that certain fixed species of marine animals are under very different conditions of nutrition from the very earliest period, according as they are high or low on the shore, and yet the pro- portions of the sexes remain unchanged—indicating that in such forms nutrition has no effect in determining sex. (3) F. P. Morena and A. Smith Woodhead, exhibition of NO. 1565, VOL. 60] and remarks on a skull of the extinct Chelonian A/zolanza from Patagonia, along with an exhibition of newly-discovered Veomy- /odon remains from Patagonia—a most interesting and important exhibit of these remarkable remains. (4) G. E. H. Barrett-Hamilton, the fur seals of the Bering Sea. An account of their habits and condition. The rest of the afternoon was occupied with reports of Com- mittees, which will be noticed below. On Tuesday, Sir John Murray reada paper on Dr. Peterson’s experiments in the Cattegat, with the marking and measuring of plaice in order to determine distribution and growth, and on plaice culture in the Limfjord. By transplanting young fish from the North Sea into the richer feeding grounds of the shallow fjord, it was found that from April to November they increased to five times their original weight. The cost of transportation was one-sixth of a penny per fish, and the price obtained for a fish so fattened was 4d¢.—a notably successful attempt at eco- nomic fish culture. Mr. W. Garstang gave an account o. his experiments at Plymouth on the artificial rearing of young sea-fish, In this Mr. Garstang has, so far, been very successful ; and has suc- ceeded in rearing about 50 per cent. of his larvae through their critical stages to the complete adult organisation. They are fed on plankton, and are kept in ‘‘ plunger” jars with not more than five larvee to a gallon of water. Dr. James Murie gave an account of the Thames Estuary : its physico-biological aspects as bearing upon its fisheries. These papers gave rise to some discussion on marine fish-culture. Prof. McIntosh, finally, gave a paper on the occurrence of the grey gurnard (77ig/a gurnardus, L.), and its spawning in in- shore and offshore waters. He shows by a monthly examination of the statistics that this important fish does not begin to move into the inshore waters for spawning purposes until after February, and attains its maximum in May. [Ile does not consider that a maximum as late as August in some years can be taken to indicate a second spawning migration, as supposed by the Scottish Fishery Board. Spawning goes on from April to September. The Reports of Committees submitted to the Section were as follows :— (1) The Naples Zoological Station.—The British Association table has been occupied by Dr. H. Lyster Jameson, who givesa summary of his work upon the anatomy of certain Gephyrea and allied vermiform organisms. The usual statistics and other information in regard to the station during the year are also given. (2) Investigations at the Plymouth Marine Laboratory.—This contains two short papers, one on the embryology of the Polyzoa, by T. H. Taylor, and the other on the rearing of larvee of Echinidze, by Prof. MacBride. Mr. Taylor’s observ- ations were made on the larve of Aowerbankia, which he successfully carried through their fixation and metamorphosis on strips of celloidin. MacBride found at Plymouth that the larvee of Echinids would only live in pure water brought from outside the breakwater. He discusses the difficulties, and the conditions necessary for successful rearing of larvee. (3) Zoology and Botany of the West India Islands.—This is the final report, and consists of a list of the publications of the Committee. The material which still remains unworked out has been presented to the British Museum. (4) Zoology of the Sandwich Islands.—This ninth report shows what has been published by the Committee during the year, and gives the plans for further exploration in the Islands in conjunction with the Honolulu Museum. (5) Bird Migration in Great Britain and Ireland.—The labour of working out the numerous records obtained from lighthouse- keepers is still being continued by Mr. Eagle Clarke, and a conclusive report is not yet possible. (6) Zoological and Botanical Publication.—The Secretary or the Committee is in correspondence with editors of academical and periodical publications, and the results will be reported on at a future meeting. (7) Index animalium.—This great piece of work is still being carried on by Mr. Sherborn, who has indexed about 1500 volumes during the last year. The first section of the Index, dealing with 1758-1800, will soon be ready for publication. (8) Pedigree Stock Records.—This report is drawn up by Dr. Francis Galton, and deals with the production of photo- graphs, under standard conditions, of prize-winners at shows of pedigree stock, in order to have exact trustworthy records of ancestry. 632 NAO E [OcroBER 26, 1899 (9) A circulatory apparatus for experimental observations on marine organisms.—The work has been carried out by Mr. F. W. Gamble at the Piel Sea-Fish Hatchery on the Lanca- shire coast ; and the observations chiefly dealt with the changes in colour, and the mechanism of ‘colour physiology in the Crustacean Hippolyte varians. On one of the afternoons Mr. J. W. Woodall took a small party of zoologists to sea in his yacht Vad/ota, to witness the trial of Mr. Garstang’s new tow net, which can be opened and closed in any depth of water. In addition to the actual pro- ceedings in Section D, it may be noted that there was a good deal in several of the other Sections that was of zoological interest. CHE SEVENTH INTERNATIONAL GEO- GRAPHICAL CONGRESS. AT the close of the Sixth International Geographical Con- gress in London in 1895 it was decided that the next meeting should be held in Berlin in 1899, under the auspices of the Berlin Geographical Society. This meeting, with its at- tendant festivities, has just been concluded, Although the actual sittings of the Congress extended only from September 28 to October 4, the proceedings began a week earlier and were con- tinued more than a week later, by a series of geographical excursions to different parts of the German Empire. Taken as a whole the Congress must be pronounced not only successful, but brilliantly so; it presents a sort of climax in respect of grandeur to the preceding meetings, and suggests that the time has now come for reconsidering the general plan of such gatherings, and starting afresh on lines of plainer living, if not of higher thinking. Here, however, we have only to sketch the work of the Congress just over, not to suggest the plan of its successor. The Council of the Berlin Geographical Society had the entire charge of the organisation, and by the usage of previous meetings the President of the Society, Baron Ferdinand von Richthofen, professor of Geography in the University of Berlin, was President of the Congress. The personal efforts of Baron Richthofen were unceasing before and during the meeting, and as no German geographer is better known or more widely respected at home and abroad, the accident of his presidency of the Society was singularly fortunate for the success and éc/at of the Congress. He was supported as secretary by Hauptmann Georg Kollm, and a number of younger geographers who formed a staff of efficient assistant secretaries, but whose names were not brought before the members. Similarly, the various honorary officials—vice-presidents, members of com- mittees, &c., whose names had appeared in circulars sent out some months before the meeting—remained unknown to most of the members, who had left their early circulars at home. There were general programmes, printed in German, English and French, detailing the work for each day, and a supplementary programme of entertainments in German only, with additions and alterations to the list of papers; but there was no daily journal giving a clear view of the work of each day, with the names of presiding officers and a summary of the work of the day before, as at the London Congress. German also was the one Janguage used in the general business, all announcements were made in German only, almost all the nocices exhibited were in German and sometimes even in the German script, which can scarcely be looked on as an international character. In London the three languages were used for every written or printed notice and every important verbal announcement. The abstracts of papers, which were circulated daily, were printed in the language of the author only. The foreigner, unversed in the German language and unused to German customs, was some- what at a disadvantage throughout, both in scientific meetings and at social functions. These minor matters apart, the organisation left nothing to desire. The grand building of the Prussian Chamber of Deputies, generously lent to the Congress by the Prussian Government, formed a perfect home for the member. A ‘* depositorium,” bearing the number of his ticket, received all communications intended for him, an admirably-conducted cloak- room relieved him of hat and coat, and restored them with a swiftness and certainty that seemed magical to the frequenter of British scientific gatherings ; a vast refreshment room could serve breakfast, lunch and supper to the whole Congress simul- NO. 1565, VOL. 60] taneously ; picture post-cards (more essential than food to the German visitor) were on sale in every room, even in the Great Hall while papers were being read ; desks were provided for issuing tickets, badges and the many offerings of books, maps, &c., presented by institutions and firms ; while the Juxurious reading- and writing-rooms of the Prussian Deputies were thrown open absolutely without reserve. As an example of international hospitality, the installation of the Congress was memorable and unique. Perhaps the best managed of all the hospitable arrangements was the Ladies’ Committee, specially charged with the care of the lady associates of the Congress, which carried out its work with most satisfactory diligence and completeness. The Congress commenced informally in true German style by the members dropping in as they arrived on the evening of Wednesday, September 27, to the restaurant of the House of Deputies, where they sat at supper or wandered through the various halls, greeting old friends and forming new acquaint- ances. Next morning at ten o’clock the formal opening took place with much dignity, the gentlemen appearing in evening dress or uniform with a profuse display of orders. Prince Albrecht of Prussia welcomed the Congress in the name of the Emperor ; Prince Hohenlohe, the Imperial Chancellor, wel- comed it in the name of the Empire; Herr Studt, the new Prussian Minister of Education, in the name of the kingdom of Prussia, the speeches of these great personages being received in solemn silence. The Burgermeister of Berlin then welcomed the members in the name of the city, and applause, which was not stinted to subsequent speakers, then began. The welcome was responded to by a few of the most distinguished foreigners. Baron Richthofen read his presidential address, on the pro- gress of geography in the nineteenth century ; Sir Clements Markham, as president of the sixth Congress, gave a short ad- dress, resigning his office and presenting the report of the London Congress. Vice-presidents and chairmen of the different sections were nominated, and the formalities were over. It is unnecessary to detail the social accompaniments of the Congress. The Imperial Chancellor gave a small dinner and a large reception to the foreigners and the more prominent German members. The city of Berlin gave an admirably conducted dinner to the whole Congress in the Zoological Gardens. The Berlin Geographical Society also entertained all the members to a reception and supper, and there was a special performance in the Opera House. It is impossible to pass without remark the magnificent hospi- tality of Hamburg, where over 500 members of the Congress were received by the local Geographical Society, and carried through two days of uninterrupted festivity. The Senate opened the State rooms of the new Town Hall, probably the finest municipal building in the world, for the first time in honour of the visitors, and an even more impressive view of the vast wealth and activity of the greatest continental seaport was afforded bya cruise through the harbour and a visit to the floating docks and ship-building works. The Hamburg-America Line entertained a thousand guests to lunch in the ‘‘’tween-decks” of the Pretoria, said to be the largest cargo steamer afloat, and this on the day before she sailed for New York with a full cargo and complement of passengers. No less hearty and no less interest- ing were the receptions accorded to the members of the various excursions to the Baltic shores, the Rhine and Central Germany by the local authorities and geographical societies. The serious business of the Congress was divided into a general meeting in the forenoon from ten to one, and three simultaneous meetings in the afternoon, commencing at two o'clock, and sitting until five or even six. A time-limit for speakers was formally announced, but rarely, if ever, enforced ; and the system of allowing one speaker to address the meeting as often as he liked on the same subject led to the degeneration of some of the debates into long-winded dialogues. The programme with its additions bore the titles of no less than 150 papers, many of which were intended to be introductory to discussions. This number might have been reduced with great advantage. A few were the work of ‘‘ cranks,” a good many were old or of no international interest ; but the great majority were new and valuable and deserving of far more complete discussion than their number made it possible for them to receive. The departments of Geography which received most attention at the Congress were, perhaps, Antarctic Exploration, Oceano- OcToBER 26, 1899] graphy and Plant-Geography. Dr. Erich von Drygalski gave a detailed account of the plans tor the German Antarctic expedition, which is to sail in 1901, and submitted the specifications for the ship and her equipments. All the preparations for the ex- pedition are in a forward state. Dr. Drygalski himself is the scientific leader, the captain of the ship being simply a sailing- master responsible for the navigation. Dr. Vanhoffen, who accompanied Dr. Drygalski in his Greenland expedition, goes as botanist, and several other members of the scientific staff, which will number at least six, have been chosen. Much stress is laid on the importance of co-operation with the British expedition. Dr. Drygalski hopes to land somewhere to the south of Kerguelen, that island being occupied by a land-party as a scientific base, and to advance towards the South Pole by the aid of dogs. Sir Clements Markham gave a full exposition of the plans of the British expedition. He said that the vessel for the expedition will be built of oak with an ice-casing of harder wood. She will be 172 feet long by 33 broad, with a dis- placement of about 1525 tons. Arrangements will be made for a magnetic observatory before the mainmast, which shall have no iron within 30 feet of it. There will be accommodation for six executive officers, including two engineers, three civilians for biology and geology, including the surgeon, and thirty-nine men. Melbourne will be the base for magnetic observations, and a party will be landed in MacMurdo Bay, near Mount Erebus, to push inland with sledges, but without dogs, the use of which involves unjustifiable cruelty. In the discussion on the Antarctic papers, Dr. Nansen strongly defended the use of dogs, the alternative being in his opinion far greater cruelty to men. Sir John Murray urged the importance of circumpolar oceanographical investigations as a preliminary to the pene- tration of the Antarctic ice-pack. M. Ar¢towski read a paper on the oceanographical and meteorological results of the Be/gzca’s voyage, and Prof. Nielsen of Christiania gave some account of Sir George Newnes’ expedition under Mr. Borchgrevink. In north polar exploration the most important papers were the first public statements regarding the scientific results of the Fram expedition, Dr. Nansen in a lecture of an hour and a half’s duration described the North Polar Basin as revealed by his soundings, and discussed the distribution of temperature and the circulation of water in it in great detail, while Prof. Mohn in another paper gave a résumé of the meteorological results. It is impossible in a few lines to summarise either of these massive contributions to knowledge. Oceanographical papers were numerous, that of Prof. Chun, the leader of the Valdevza expedition, exciting the greatest amount of interest. Sir John Murray discussed the distribution of deep-sea deposits over the ocean floor, and the Prince of Monaco described some of the results of his recent cruise to Spitsbergen. Several useful and really international discussions took place, culminating in the appointment of committees to draw up a systematic terminology and nomenclature for the forms of sub-oceanic relief, introduced by Profs. Wagner, Kriimmel, Voiekoff and Dr. H. R. Mill, and to determine a common method of expressing the density of sea-water, intro- duced by Baron Wrangell and Prof. Pettersson. There were several valuable papers on subjects involving climatology, limnology, the study of glaciers and seismology, and one on kumatology by Mr. Vaughan Cornish; indeed it would be difficult to mention any department of physical geo- graphy to which some contribution was not made. The geography of plants was discussed with particular thoroughness, both with regard to the distribution of special types of vegetation and the more general relations of nomen- clature and cartographic representation. Profs. Drude, Engler, Warburg, Krasnoff and Nehring dealt with these subjects. The geological aspects of geography produced several papers of unusual value, including one by Prof. de Lapparent on the question of peneplains, one by Prof. Penck on the deepening of alpine valleys, and one by Mrs. Gordon (Dr. Maria Ogilvie) on the basins of southern Europe. Mr. W. Obrucheff, of St. Petersburg, gave an important account of the orography and tectonic structure of the trans-Baikal region of Siberia as revealed by the most recent observations—between 1895 and 1898 ; and Prof Philippson discussed the AZgean region in a similar. way. The human and historical aspects of geography were not left in the background. Prof. Raizel discoursed on the origin and dispersal of the Indo-Germanic peoples, and Prof. Sieglin on the discovery of England in ancient times. Papers were read NO. 1565, VOL. 60] NATURE 633 on the need of fresh organisation in obtaining statistics ot population in unorganised countries by Dr. Scott Keltie, and on means of representing such statistics on maps by Prof. Hettner. Prof. Neovius, of Helsingfors, exhibited a remarkable atlas of Finland recently completed by the Finnish Geographical Society, in which all the conditions of the land, natural and economic, are mapped with a completeness that has never been attempted for any other country. It even includes a map showing in horse-power the available energy of the rivers. As was to be expected there were many papers on geography in its educational aspects. Amongst these one by Prof. Ratzel on geographical position as the central fact in geographical educa- tion was perhaps the most important. The last meeting of the Congress was to have been addressed by Prof. Hergesell on the results of international balloon in- vestigations, but the author somewhat rashly made an ascent the previous morning in a balloon, which carried him so far towards the Russian frontier that the Congress had been formally closed before the slow means of terrestrial locomotion brought him back to Berlin. No better bird’s-eye view of the work of the Congress can be given than by presenting in a condensed form the series of resolutions passed at the final meeting, which are intended to minister to more complete international co-operation in the work of scientific investigations. RESOLUTIONS OF THE SEVENTH INTERNATIONAL GEOGRAPHICAL CONGRESS. (The order is that in which the resolutions were presented. ) (1) The Congress appoints a Committee of Bio-geographers resident in or near Berlin to draw up a uniform scheme of nomenclature for plant-formations, and after consultation with non-resident specialists, to revise the same and present it to the Eighth Congress. (2) The Congress believes that the plans for international co- operation in Antarctic exploration form an excellent basis for joint research in physical geography, geology, geodesy and biology. With regard to meteorological and magnetic work, however, they appoint an international committee to determine the general scheme and methods to be employed on the expeditions, and to endeavour to organise a system of simultaneous observations in the regions surrounding, but exterior to, the Antarctic. (3) The Congress expresses the earnest desire that all maps, including those published in countries using English and Russian measures, should, in addition to the graphic scale, bear the pro- portion of lengths on the map to those in nature in the usual form I:x. (4) The Congress views it as desirable that the publication of all new geographical material accompanying accounts of travel, should be supported by details regarding the methods of survey- ing, the instruments employed, and their verification, the calcu- lation of astronomical positions with their probable error, and the method of utilising these data in preparing the map. Also that all maps published by scientific men, institutions or govern- ments should be accompanied by notes of the principal fixed points. (5) The Congress expresses the hope that a uniform system of measures will be used in all geographical researches and dis- cussions, and recommends that the metric system of weights and measures be so employed. (6) The Congress expresses the hope that in scientific public- ations the centigrade thermometer scale should, as far as possible, be employed; or, at least, the values in centigrade degrees added to those expressed on the scales of Fahrenheit or Réaumur. (7) With regard to the proposal to introduce a decimal division of time and angles, the Congress desires to preserve the present division of time and of the citcumference into 360°, but allows that the adoption of a different subdivision of the angle might be studied, and considers that in certain cases the decimal subdivision of the degree of arc presents no objection. (8) The Congress is of opinion that the Bié/iotheca Geographica, published by the Berlin Geographical Society, may be accepted as an efficient international bibliography of geography. (9) The Congress considers the construction of statistical population maps to be very desirable, and appoints an inter: national committee to draw up a scheme, at the same time expressing the hope that national committees will be formed in various countries to promote the preparation of such maps. (10) The Congress considers the collection of data as to the 634 distribution of floating ice to be very important, and appeals to the hydrographic and meteorological institutes of the countries whose ships frequent high latitudes to induce the masters of vessels to keep a regular record of the occurrence of drifting ice. The Congress believes that the Danish Meteorological Institute in Copenhagen is the best adapted as an international centre for collecting the records. (11) The Congress nominates an international committee to consider the nomenclature of the floor of the ocean, and to produce and publish at latest in time for the next Congress a chart of the ocean with revised nomenclature. (12) The Congress hopes that the names of oceanic islands, especially in the Pacific, will be revised witha view to ascer- taining and preserving the native names. Where no native names exist or can be ascertained, the names given by the discoverers should be used. The arbitrary changing of established names ought to be opposed by every means. (13) The Congress recognises the desirability of obtaining data for a more exact estimate than now exists of countries in which there is no means of taking a census, and desires to bring the matter to the notice of such Governments as have foreign possessions. (14) The Congress expresses sympathy with the proposal to equip an expedition in New South Wales, with the sole object of endeavouring to discover remains or traces of the route of the Leichhardt expedition, which perished in the interior of Australia fifty-two years ago. (15) The Congress is favourable to the foundation of an inter- national seismological society, and appoints an international committee for the study of earthquakes. (16) The Congress believes the production of a map of the world on the scale of I: 1,000,000, the sheets bounded by meridians and parallels, to be both useful and desirable. The Permanent Bureau of the Congress is instructed to deal with the question, and in the first instance to secure the preparation of a projection for the map with degree-lines on the determined scale. (17) The Congress considers the establishment of an Inter- national Cartographical Association of service, and appoints a committee to take preliminary steps. THE SCIENTIFIC CONFERENCE AT WIESBA DEN. E refer in a leading article to one of the most important developments of scientific organisation which our time has seen. The proceedings at a recent conference at Wiesbaden, dealing with this matter, are thus stated in Monday’s 7¢mes :— “* For ‘several years past there has existed an Association or Cartell of the Academies of Sciences of Munich and Vienna and of the Royal Societies of Sciences of Gottingen and Leipzig. which has met yearly to discuss matters of common interest, and the combined action of these bodies has in several ways been fruitful of results. Representatives of the Royal Society of London attended the meeting held last year at Gottingen, as well as that which took place the previous year at Leipzig, chiefly with the object of discussing the project of an inter- national catalogue of scientific literature which the society has been engaged in promoting. “*When the invitation was conveyed to the Royal Society of London to send representatives to the Gottingen meeting it was intimated that the Cartell would be glad to learn the views of the society as to the possibility of its joining the association. The delegates appointed from London were instructed to state that the Royal Society would be disposed to join provided that the organisation were so extended as to assume a truly inter- national character. This suggestion was not only accepted in principle at Gottingen, but it was agreed that the Royal Society of London should be requested to take the steps, if thought desirable, to ascertain how far the establishment of such an international association would commend itself to the leading scientific bodies of other countries. ‘*The Royal Society of Sciences of Berlin, although not in- cluded in the Cartell, has for several years past been repre- sented at its meetings. When the Royal Society of London had ascertained that the project was likely to find favour it was agreed that the Royal Society and the Berlin Academy should together issue an invitation to the Academy of Science, Paris, the Imperial Academy of Sciences, St. Petersburg, the NO. 1565, VOL. 60] NATORE [OcTOBER 26, 1899 Reale Accademia dei Lincei, Rome, the National Academy, Washington, U.S.A., as well as to the bodies included in the Cartel!l, requesting them to send delegates to a conference to be held in Wiesbaden on the roth and rith of this month. “At the conference, excepting the Reale Accademia dei Lincei, which was unable to send delegates, although in full sympathy with the movement, all the bodies invited were represented—the Berlin Academy by Messrs. Auwers, Virchow and Diels ; the Gottingen Society by Messrs. Ehlers and Leo ; the Leipzig Society by Messrs. Windisch and Wislicenus ; the Royal Society by Messrs. Riicker, Armstrong and Schuster ; the Munich Academy by Messrs. von Zittel Dyck and von Sicherer; the Paris Academy by Messrs. Darboux and Moissan ; the St. Petersburg Academy by Messrs. Famintzine and Salemann; the Washington Academy by Messrs. New- comb, Remsen and Bowditch; and the Vienna Academy by Messrs. Mussafia, von Lang, Lieben and Gomperz. “Prof. Auwers, one of the secretaries of the Berlin Academy, occupied the chair, and the success of the meeting was largely due to the extreme ability and tact, combined with judicious firmness, with which he conducted the proceedings, Besides showing himself a master of the three languages—German, French and English—used in the debates, he was thoroughly informed on every point which came up for discussion. Fortunately, all the delegates appeared to be actuated by the desire to co-operate, and there was little difficulty in framing statutes which all were prepared to accept. “The immediate outcome of the conference has been that it is resolved to found an international union of the principal scien- tific and literary bodies of the world, the object of which will be to initiate or promote scientific enterprises of general interest recommended by one or more of the associated bodies, and to facilitate scientific intercourse between different countries. It is to be known as the International Association of Academies. A number of important bodies besides those represented at Wiesbaden are to be invited to join. General meetings of delegates from the various constituent academies are to take place, as a rule, at intervals of three years, but the interval may be varied and special meetings held if necessary. The Royal Society had proposed, prior to the conference, that the first general meeting should be held in Paris next year. At the general meetings two sections will be constituted, one dealing with mathematics and the natural sciences, the other with arts and philosophy. ‘© A council is to be appointed which will carry on the business in the intervals between meetings. The formation of committees of experts to initiate and promote scientific investigations of international importance is also contemplated. “* Tt remains to be mentioned that the Berlin Academy had also arranged for the entertainment of the delegates at the close of the debates. On the Monday evening they were invited to attend a performance of Lortzing’s opera Undine, and on the Tuesday they were entertained at dinner in the Kurhaus. On the latter occasion Prof. Virchow occupied the chair, and opened the proceedings by toasting the delegates generally ; he was followed by Prof. Darboux, of Paris, who proposed the health of the Berlin Academy. In the course of the evening, in characteristic German style, every other possible toast was proposed by one or other of the delegates. “Tt is to be hoped that when the statutes framed at the con- ference are communicated to the various bodies interested they will meet with approval, and that the establishment of the organisation will soon be an accomplished fact. In times when political feeling is so strongly developed the provision of a common platform on which all nations can meet amicably and co-operate in furthering scientific enterprises must prove of the very greatest value; and if the spirit of amity which prevailed at the conference be extended to future meetings the success of the association is assured.” UNIVERSITY AND EDUCATIONAL INTELLIGENCE. CAMBRIDGE.—Sir Michael Foster has been reappointed a manager of the Balfour Fund for zoological research. Mr. Yule Oldham, reader in geography, is giving three courses of lectures this term: (1) on the Geography of Europe, for history students; (2) on Physical Geography ; and (3) on the History of Geographical Discovery. OcToBER 26, 1899 | The degree of M.A. honoris causa is to be conferred on Dr. Somerville, the recently-elected Professor of Agriculture. ' Mr. W. N. Shaw, F.R.S., is reappointed Assistant-Director of the Cavendish Laboratory. Prof. D. J. Cunningham, F.R.S., of Dublin, is appointed an Elector to the chair of Anatomy, and Prof. W. F. R. Weldon, F.R.S., of Oxford, an Elector to the chair of Zoology, in succession to the late Sir W. H. Flower. Dr. D. MacAlister, of St. John’s College, has been re-elected a representative of the University on the General Medical Council for five years. Fifteen candidates have passed the recent examination in sanitary science, and have thus qualified for the Diploma in Public Health. THE destruction of the Technical Institute at West Ham by a fire which occurred on Monday night, and was first discovered in the chemical laboratory, is a disaster to technical education in London. The Institute commenced a short time ago an admirable programme of work in science and technology, and as it was the only municipal technical institute in the metro- politan area, its career has been closely followed. The damage done is estimated at over 80,000/., only part of which is covered by insurance. THE systematic study of geography is so much neglected in this country that it is to be hoped the School of Geography recently established at Oxford will be successful. During the present term Mr. H. J. Mackinder, the University Reader in Geography, will lecture on the historical geography of the British Isles. The lecturer in physical geography (Mr. Dick- son) will lecture on the climate of the British Isles. The assistant to the Reader (Dr. Herbertson) will lecture on the geomorphology of Europe; and the lecturer in ancient geography (Mr. Grundy) will lecture on the general historical topography of Greece. Dr. Herbertson will give instruction in cartography and practical geography, with field work ; and during the term special attention will be given to the study of map projections, and of physical maps of all kinds. ANOTHER addition to the laboratory equipment of our public schools has recently been made at Felsted, where new buildings for the teaching of science were opened last week. The laboratory consists of a lecture room with raised seating and a gallery, the lecture table being provided with down draught and electricity for experimental purposes, and behind it a faced wall surface for the lantern. The chemical laboratory is a room about thirty feet square to accommodate twenty-six boys, and has an adjoining balance room. In addition there is a general physical laboratory for a like number of boys, a special laboratory for senior physics, an optical room, store room and workshop. The building is in a large measure a gift of one of the governors of the school, and has been erected under the direction of Mr. A. E. Munby. It was opened by Dr. Garnett, of the London County Council, who gave an address on science as a means of general education. Sir John Gorst recently visited the building and expressed his warm approbation of the arrangements. PRACTICAL science in rural districts, as a means of benefiting British agriculture, has, we are glad to observe, received much support lately. The meeting of the Agricultural Education Committee, held at the Society of Arts on Friday last, showed the existence of a strong feeling that active efforts should be made to secure systematic and efficient instruction, both theoretical and practical, in agricultural subjects suitable to every class engaged in agriculture ; and to diffuse among the agricultural classes a more thorough appreciation of the ad- vantages of instruction bearing directly or indirectly on their industry. The chairman, Sir William Hart Dyke, explained that the province of the committee, as a united body, was to bring pressure upon Parliament and upon public opinion to establish in rural schools rational courses of instruction bearing upon agricultural pursuits. The following resolutions were subsequently adopted :—(1) That, in the proposed organisation of the new Board of Education, due regard should be had to the interests of agricultural instruction. (2) That proper provision should at once be made at certain of the Teachers’ Training Colleges for giving to those who desire it both theoretical and practical instruction in subjects bearing on agriculture and horti- culture. (3) That, after a certain date to be named in next year’s code, instruction in the elementary branches of natural NO. 1565, VOL. 60] NATURE 635 science bearing on agriculture should be made compulsory in rural elementary schools, and that such instruction should be accompanied and illustrated by experiments, and (where possible) by practical work in plots of ground attached to the schools. (4) That county authorities be encouraged to provide experimental and school farms, and to contribute, by scholar- ships and otherwise, to some agricultural college or department of the first rank. The realisation of the conditions expressed in these resolutions should be desired by every one interested in national progress. SCIENTIFIC SERIAL. Wiedemann’s Annalen der Physik und Chemte, No. 9.— Dispersion of gypsum, by W. Konig. The author studies the dispersion of gypsum in the visible spectrum by observing the influence of wave-length upon the width of interference fringes produced by means of wedges made of that material. —Electric charge of freshly-prepared electrolytic gases, by W. Kosters. Hydrogen and oxygen are positively electrified by passing through sulphuric acid, and this may help to explain the posi- tive charge of the same gases when produced by electrolysis. In other cases, however, the gases passed through a liquid do not assume the same electrification as when generated by electro- lysis. Further experiments with Becquerel rays, by J. Elster and H. Geitel. Thinking that the radiation of uranium and thorium compounds might be influenced by the impact of kathode rays, the authors exposed a piece of Joachimsthal pitchblende to kathode rays, but they could not trace any in- fluence of the rays. The authors believe the Becquerel rays to be Réntgen rays of small intensity. They support this view by show- ing that they are not deflected by a magnet (see p. 623).—Radio- active barytaand polonium, by F. Giesel. The author describes the preparation of the radio-active bariym salts. He has not yet succeeded in isolating the active principle, whether radium or polonium,—Canal and kathode rays, by P. Ewers. The writer does not share the prevalent opinion that canal rays consist of projected anode particles, since the quantity of elec- tricity conveyed by them varies with the material of the kathode, but not with that of the anodes. He concludes that the canal rays consist of positive ions of the material of the kathode, but the matter thus conveyed to the wall is so small that it would require 288 hours of continuous working to deposit one milli- gramme of aluminium.—Law of development of Hittorf’s dark space, by H. Ebert. Hittorf’s dark space is the narrow space which immediately adjoins the luminous kathode layer. Its width increases as exhaustion proceeds, and does so in accord- ance with a geometrical series when the pressure diminishes in another geometrical series. The indices of the series are, however, generally different.—Magnetic susceptibilities of in- organic compounds, by S. Meyer. Judging from their com- pounds, the rare elements lanthanum, cerium, praseodymium. samarium, gadolinium, and especially erbium, must be strongly magnetic. Erbium oxide is four times as strongly magnetic as Fe,O3, and if the conclusion as to their bases is correct, erbium must be, weight for weight, six times as strongly magnetic as iron. This would have an important practical signification if erbium were to be found in large quantities. SOCIETIES AND ACADEMIES. Paris. Academy of Sciences, October 16.—M. van Tieghem in the chair.—On the positions of equilibrium of a ship carrying liquid cargo, by M. Appell. The author develops a problem of M. Guyou, giving a means of finding the positions of equilibrium and discussing their stability.—Method of setting a collimator, by M. G. Lippmann. The slit is observed with an auxiliary telescope, and between this and the collimator a biplate is in- serted. In general two images of the slit are observed, but on adjusting the collimating lens, at one point the two images co- incide ; the rays issuing from the collimator are now parallel. The accuracy of the adjustment is limited only by the resolving power of the telescope.—Production of ozone by the decom- position of water with fluorine, by M. Henri Moissan. _ A rapid current of fluorine, prepared in a copper apparatus, is passed 636 NATURE [OcroBER 26, 1899 into water kept at 0°. The ozonised oxygen thus set free was carefully analysed by treatment with potassium iodide and measuring the iodine set free. The percentage of ozone was on one occasion as high as 14°4 per cent., and this preparation, al- though somewhat delicate, is not costly. The ozone produced in this way is absolutely free from all trace of oxides of nitrogen, and may possibly have industrial applications.—The preventive qualities of the blood serum of an immunised heifer against contagious peripneumonia in cattle, by MM. S. Arloing and Duprez. The direct inoculation for peripneumonia suggested by M. Willems has two disadvantages: some time is required to develop the protective effects, and occasionally fatal tumours occur. A heifer was directly inoculated with gradually increasing amounts of venom until it became capable of resisting a dose five hundred times greater than would be sufficient to kill an unprotected animal. The serum of this heifer was used in the experiments, which were not alto- gether conclusive, since one of the injected animals caught the disease, whilst another, although unprotected, escaped. — Report on an earthquake at Smyrna on September 20, by the French Consul General at Smyrna.—Observations of the Giacobini Comet (September 29, 1899), made at the Observ- atory of Algiers, with the equatorial of 31°6 cm. aperture, by MM. Rambaud and Sy.—On a problem relating to the con- gruences of right lines, by M. E. Goursat.—On the classification of projective groups in space of 7 dimensions, by M. F. Marotte. —Theory of the number of roots of an algebraic equation comprised in the interior of a given circumference, by M. Michael Petrovitch.—On the reactions of induction of alter- nators, by M. A. Blondel.—Experiments in telegraphy without wires, carried out between Chamonix and the summit of Mont Blanc, by MM. Jean and Louis Lecarme. The communications were interfered with by the ice, or by the absence of water in the soil ; neither were the effects of atmospheric electricity sufficient to stop the messages, but during the time the electric lightat Chamonix was in action working was impossible. —Radio- graphic bulb with a cold antikathode, by MM. Abel Buguet and Victor Chabaud. The platinum tube forming the antikathode is fused directly to the glass, and is kept cool by cold water. Very powerful discharges from large induction coils can be used with this tube without any heating of the platinum resulting. — ‘On a new radio-active material, by M. A. Debierne. A new radio-active substance has been isolated from pitchblende. It as distinguished from polonium and radium by its chemical properties, which resemble titanium very closely, and also by the fact that itis not spontaneously luminous. The rays emitted by this substance, for which no name is as yet sug- gested, are about 100,coo times stronger than those given off by uranium. They render gases capable of discharging electri- fied bodies, excite the phosphorescence of barium platinocyanide, and affect photographic plates. —On the atomic weight of boron, by M. Henri Gautier. The author, after reviewing the earlier work of Berzelius, Abrahall, and Ramsay and Aston, attempts to prepare compounds of boron of the constancy of composition of which there can be no doubt, and selects the sulphide B,S; and carbide B,C for a preliminary study.— On anhydrous magnesium carbonate, by M. R. Engel.—On the heat of oxidisation of tungsten, by MM. Delépine and Hallopeau. The usual methods of combustion at ordinary pressure, combination with a halogen, attack by water or acid having failed for tungsten, the method of burning in the calori- metric bomb was tried, and after some preliminary experiments was found to give good results, the mean value per gram of tungsten being 1062 calories. In forming the oxides TuO, and TuQOs, each atom of oxygen has nearly the same calorific value. —Action of potassium-ammonium upon arsenic, by M. C. Hugot. With the alkaline ammonium in excess, AsKg is formed ; with arsenic in excess, As,K,.—Action of bromine in presence of aluminium chloride upon some chloro-benzenes, by M.M. A. Mouneyrat and Ch. Pouret. Bromine acts readily upon chlorobenzene in presence of aluminium chloride, and gives an excellent yield of #-bromo-chlorbenzene. The allowing compounds have been obtained by this method: Br;Cl, [1, 4] CgBr,Cly, [1, 2, 4] C,Br3Cly, [1, 2, 4, 5] CgBreCl4, fa Cc Br,Cl(CH, ).—On the constitution of the colouring matter of leaves ; chloroglobin, by M. Tsvett. —Demonstration of the disaggregation of leucocytes and the solution of their contents in the. blood plasma during hypoleucocytosis. In- fluence of intravascular leucolysis on the coagulation of the blood, by M. Henri Stassano.—Germination of the seed of the NO. 1565, VOL. 60] carob; production of mannose by a soluble ferment, by MM. Ed. Bourquelot and H. Heérissey. During the germination of the carob seed there is soluble ferment produced, which acts upon the stored albumen similarly to diastase upon amylaceous talbumens, mannose and galactose being the products.—On Aplosporidium, a new order of the class of Sporozoa, by MM. Maurice Caullery and Félix Mesnil.—Calcified suberous layers from the coal measures of Hardinghen, by M. C. Eg. Bertrand. —On the composition and food value of the principal fruits, by M. Balland.—Submarine lithology of the coasts of France, by M. J. Thoulet. DIARY OF SOCIETIES. THURSDAY, Octoser 26. at 8.15.—Illusions and Anomalies of Vision : FRIDAY, Octoser 27 Prysicat Society, at 5.—The Magnetic Properties of the Alloys of Iron and Aluminium: Dr. S. W. Richardson.—Exhibition of a Model illus- trating a Number of the Actions in the Flow of an Electric Current : G. L. Addenbrooke —Repetition of some Experiments with the Wehnelt Interrupter devised by Prof. Lecher: W. Watson INSTITUTION OF MECHANICAL ENGINEERS, at 7.30.—The Incrustation of Pipes at Torquay Water Works: William Ingham.—A Continuous Mean-Pressure Indicator for Steam Engines: Prof. William Ripper. WEDNESDAY, NoveMBER 1. EnTomo_Locicat Socigrry, at 8.—Exhibition of Lepidoptera from Bul- garia: H. J. Elwes, F.R.S., and Mrs. Nicholl. Socrety or Pustic ANALYSTS, at 8.—The Meaning of the Acetyl Value in Fat Analysis (with Lantern Illustrations) ; Dr. J. Lewkowitsch. THURSDAY, NoveMBER 2. LinnEAN Society, at 8.—On the Proliferous State of the Awn of Nepal Barley: Rev. Prof. Henslow.—On the Hyobranchial Skeleton and Larynx of the New Aglossal Toad, Hymenochirus Boettgeri: Dr. W.G. Camera C Lup, Shelford Bidwell, F.R.S. Ridewood.—On the Eye-spot and Cilium in Euglena viridis: Harold Wager. CHEMICAL Society, at 8.—The Theory of Saponification: J. Lewkowitsch. —The Action of Dilute Nitric Acid on Oleic and Elaidic Acids: F. G. Edmed.—Tetrazoline : Siegfried Ruhemann and H. E. Stapleton.—On Ethylic Dibromobutanetetracarboxylate and the Synthesis of Tetrahydro- furfuran-aa’-dicarboxylic Acid ; Dr. Bevan Lean.—(1) Camphoroxime. Part III. Behaviour of Camphoroxime towards Potassium Hypobromite ; (2) Optical Influence of an Unsaturated Linkage on certain Derivatives of Bornylamine : Dr. M. O. Forster. CONTENTS. PAGE The International Association of Academies . . . 613 A Pioneer in Telegraphy . . ono LNs} Our Book Shelf :— F.R.A.S. : ‘* The Maintenance of Solar Energy”. . 615 ‘* Official Report of the National Poultry Conference held at Reading in July 1899” . . 615 Brend: ‘* The Story of Ice in the Present and Past” 615 Letters to the Editor :— Effect of Vibration on a Level Bubble. (W27h Diagram.)—A., Mallock . . Me ol OMG Rural Education.—John C. Medd ; Prof. R. Meldola, F.R.S. . . 616 On the Distribution of the Various’ Chemical Groups of Stars. (J///ustrated.) By Sir Norman Lockyer, K.C.B., F-RIS) 2); 617 The Parent-Rock of the South African Diamond! Byserot, T. G. Bonney iakes-ee . . = Saeco Notes; . .. 0/0 OIG cco 6 (GRR Our Astronomical Column: : Eolmes’ ‘(Comet (18992) aewemeeies @ ... O Nova Sagittarii . . 50.6 Oe RARIRAIO B co | OR Orbit of Eros . ; 5 2G SOND Goat Oe Strassburg Observatory sited 2 . 625 The Nerve-Wave (La Vibration INerveuse). (With Diagrams.) By Prof. Charles Richet crooner (Ps Zoology at the British Association sy5) 1030 The Seventh International Geographical Congress 632 The Scientific Conference at Wiesbaden .. . . . 634 University and Educational Intelligence See OSH ScientiiiciSerial’ | ? 0a |. ln 635 Societies and Academies. ............ 635 Diary of Societies 50 > KUO MERMEGRED Ho cy Oo (lt{S) “© To the solid ground Of Nature trusts the mind which builds for aye.”—WORDSWORTH. No. 1540, VOL. 60] DEER OIRS IOIAYS Registered as a Newspaper at the General Post Office.] MAY 4, 1899. [PRICE SIXPENCE. [All Rights are Reserved. NEWTON -& CO.’S GARDEN SUN-DIALS. From 4 in., 20s., to 18 in., £8 10s. FULL AND DESCRIPTIVE PRICE LIST ON APPLICATION, BRASS CIRCULAR HORIZONTAL SUN-DIALS. NE co. OPTICIANS TO THE QUEEN & GOVERNMENT7, 3 FLEET STREET, LONDON. ~ BROWNING’S ‘“*PANERGETIC” BINOCULAR OPERA, FIELD AND MARINE GLASS. Has 12 Lenses, gives a very large field of view, and exhibits objects with remarkable brightness and clearness. The ‘‘ Panergetic” is the best Binocular, for general use, made; only its price has prevented it from being more widely known and used. Now it is reduced nearly half in i The medium size in_ Black Enamel being £2 5s., and in Alum- inium £38, in best Cases complete. FULL PARTICULARS BY POST. JOHN BROWNING, 63 STRAND, LONDON, W.C. BEC FE’ NEW MICROSCOPE THE “ BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Eye-piece; Double Nose- piece, Two Object-glasses, 2/3” and 1/6’, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 No. 55. R. & J. BECK, Ltd., 68 CORNHILL, LONDON, E.C. N EGRETTI & ZAMBRA'S 7 | | IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST FREE. AND MADE ONLY BY NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, 38 HOLBORN VIADUCT, E.C. Branches— 45 CORNHILL, E.C., and 122 REGENT STREET, W. INVENTED il NATOGRE | May 4, 1899 MASON UNIVERSITY COLLEGE, BIRMINGHAM. FACULTY ‘OF SCIENCE. RESEARCH SCHOLARSHIPS. 1 by the late T. Aubrey Bowen, Esq., of Melbourne, Australia.) (2) TWO BOWEN SCHOLARSHIPS in ENGINEERING, each of the value of about £96. (2) ONE BOWEN. SCHOLARSHIP in. METALLURGY value of about £096. $ (.) THREE PRIESTLEY SCHOLARSHIPS in CHEMISTRY, each of the value of about £06. The object of these SCHOLARSHIPS is to encourage Higher Work and h in Scientific Professional Engineering and in Chemical and Metal- iclence. ’, of the Resea {urgical Applications, supported by details of educational training and re- ferences to former Teachers and others, should be sent to the REGISTRAR on or before June 1, 1899. The Aw ards will be made in September next, and the Scholarships will be tenable during the Session 1899-1900. Further particulars may be obtained on application to the REGISTRAR. ZOOLOGICAL SOCIETY OF LONDON. A COURSE of EIGHT POPULAR LECTURES on AQUATIC MAMMALS will be delivered in the Lecture Room in the Society's Gardens, Regent's Pants on THURSDAYS, at 4 p.m., commencing MAY 4, by Mr. F. E. Bepparp, M.A., F.R.S., Prosector to the Society. Tickets for the whole Course, including “Wntrance to the Gardens, 8s. each, yr 1s. each Lecture, not including Entrance, can be obtained on application to the SECRETARY, 3 Hanover Square, W. : the Shilling Tickets can also be had of the CLERK, at the Kiosk in the Gardens. Fellows are admitted ifree. THE GLASGOW AND WEST OF SCOTLAND TECHNICAL COLLEGE. CHAIR OF ELECTRICAL ENGINEERING. The Professorship ot Electrical Engineering in this College is about to become vacant, and the Governors invite applications for the position. In addition to high scientific qualifications, considerable experience in Practical Electrical and Mechanical Engineering will be necessary. Minimumsalary, £400 ayear. Duties to begin from October 1 next. Applic tions, with 15 printed copies of testimonials, to be sent in to the oF THE COLLEGE, 38 Bath Street, Glasgow, not later than UNIVERSITY ORS ANDREWS. CHAIR OF PATHOLOGY. In accordance with the terms of Ordinance No. 47 (St. Andrews, No. 6) of the Commissioners, under the Universities (Scotland) Act 1889, the University Court will appoint a PROFESSOR’ OF PATHOLOGY, who shall conduct Classes at Dundee qualifying for graduation in Medicine ; 3 the appointment to date from October 1, 1899. Applications, accompanied by twenty copies of testimonials, to be lodged by 21st JUNE next, with Mr. J. E. Wixttams, Secretary of the University, from whom further information may be obtained. St. Andrews, May 1899. = INSTRUCTION IN PURE CULTIVATION OF YEAST, According to HANSEN'S Methods. Courses for Beginners, as well as tor Advanced Students, in Physiology and Technology of Fermentations—Biological Analysis of Yeast. Manual . Chr. Hansen: ‘ Practical Studies in Fermentation. London (Spon), 1896. Alfred Jérgensen: ‘‘ Micro-organisms and Ferment- ation.’ London (F. W. Lyon), 1893. Further Particulars on Application to the Director, ALFRED JORGENSEN, The Laboratory, Copenhagen. V. RESEARCH. | CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and othér Work. y;immersion for MICRO-PHOTOGRAPHY. Workshop for Ane, Apparatus. ELECTRIC MAINS, powerful Constant Currents. ““T. " g Heathcote Street, Gray's Inn Road. RESEARCH (Biological). —- COLLABOR- ATEUR (or PUPIL) WANTED by Man of Science in important york to be shortly published. Use Laboratory. Terms by arrange- ment. Good Mathematics and Physics preferred.— Write ‘‘ScreNcE,” o NATURE. wi Lady wishes to hear of Opening for 1, aged 15 (Zoology).—Mrs. BrirTEeNn, Ivyholt, New Eltham, Kent. PARTNER WANTED in a SCIENTIFIC MANUFACTURING BUSINESS, with £3000 to £5000. Would suit Scientific Man or Son; exceptional opening ; Capital wanted to plage the Business and carry out the Orders in hand, and to enable ye increasing demand to be met. Profits very large.—Address CIENTIFIC,” care of NATURE Office. BIRKBECK INSTITUTION, Breams Buildings, Chancery Lane, E.C. Principat: G. ARMITAGE-SMITH, M.A. DAY AND EVENING CLASSES. UNIVERSITY OF LONDON. —Complete Day Courses for all the Examinations. in Science, and Complete Evening Courses for all the Examinations for the Science, Arts, and Law Degrees. SCIENCE CLASSES in every Branch, with Practical Work. Well- equipped - Laboratories for Chemistry, Physics, Biology, Botany, Geology, Mineralogy, and Metallurgy. “CONJOINT BOARD : Lectures and Practical Work in Chemistry, Physics, Biology, and Practical Pharmacy. NEW TERM for Conjoint Board and Inter. M.B. Examinations has just commenced. Prospectus, Calendar (6d.), and Syllabuses of Classes on application to the Secretary. - BEDFORD GRAMMAR SCHOOL. FIVE DEPARTMENTS. CrassicaL, Civic aND Miuirary, TECHNICAL, Hight Exhibitions, eighteen Head Master’s Nominations to be competed for May 23. Apply SECRETARY. TUITION.—ALL EXAMINATIONS —MEDICAL AND SCIENTIFIC. Well-fitted Laboratories.— SoRe C9 Heathcote Street, Mecklenburgh Square. FROM WALTER SCOTT'S LIST. THE CONTEMPORARY. SCIENCE SERIES. Edited by HAVELOCK ELLIS. Crown 8vo, Cloth, 3s.°6@. ; some Volumes, 6s. NEW VOLUMES. With a large number of Illustrations and Diagrams. By A. Junior, PREPARATORY. Illustrated. Price 6s. THE NATURAL HISTORY OF DIGESTION. LockHart GILiEspre, M.D., F.R-€.P. Ed., F.R.S, Ed. Price 6s. “With Illustrations. DEGENERACY: its Causes, Signs, and Results. By Professor EuGENE.S. Tarsot, M.D., Chicago. VOLUMES ALREADY ISSUED. The Evolution of Sex. By Prof. | The Man of Genius. By Prof. Patrick Geddes and ‘J. Arthur | Lombroso. 3s. 6d., Thomson. 3s. 6d. 5 Property: Its Origin. By Electricity in Modern Life. By Letourneay. 3s, 6d. G. W. de Tunzelmann. 3s 6d. Voleanoes. By Be E. Hull, The Origin of the Aryans. By LL.D,; F.R:S. 6d. Dr. Taylor. 3s. 6a. rE Publie Health Prabloms: By Physiognomy and Expression. | Dr. Sykes. 35. 6d. : By P. Mantegazza. 3s. 6d. | Modern Meteorology. By Frank Evolution and Disease. By J. Waldo, Ph.D. 3s. 6d. B. Sutton, F.R.C.S. 3s. 6d. | The Germ-Plasm. A Theory of The Village Community. By | Heredity: By Prof Weismann. G. L. Gomme. 3s. 6d. 6s. The Criminal. By Havelock | The Industries of Animals. By Ellis. 3s. 6d. F. Houssay. 35. 6d. Sanity and Insanity. By Dr. Man and Woman. By Havelock C. Mercier. ~3s. 6d. Ellis. 6s. Hypnotism. By Dr. Albert Moll. Modern Capitalism. By J. A. Hobson, M.A. 3s. 6d. Apparitions and Thought- Transference. By Frank Pod- more, M.A. 35. 6d. Comparative Psychology. By C. L. Morgan. 6s. The Origins of Invention. By Otis T. Mason. 3s. 6d. The Growth of the Brain. Fourth Edition. 3s. 6d. Manual Training. By Dr. C. M. Woodward. 3s. 6d. | The Science of Fairy Tales. By Edwin Sidney Hartland. 3s. 6d. Baove Folk. By Elie Reclus. 38. 6¢ Evolution of Marriage. By | Letourneau. 35. 6d. | Bacteria and their Products. By Henry Herbert Donaldson. By Dr. Sims Woodhead. 3s. 6a. 3s. 6d. Education and Heredity. By | Evolution in Art. By Prof. A. J. M. Guyau. 3s. 6d. C. Haddon. 6s. The New Psychology. By Dr. Hallucinations and Illusions. E. W. Scripture, Ph.D. 6s. | Sleep: its Physiology and | Pathology. By Marie de Manaceine. 3s. 6d. Lonpon: WALTER SCOTT, A Study of the Fallacies of Per- ception. By Edmund Parish. 6s. The Psychology of the Emo- tions. By Prof. Th. Ribot. 6s. LIMITED, PATERNOSTER SQUARE. With a Map of Cheshire and a Photogravure Portrait. Crown 8vo, ros. 6a’. net. THE FLORA OF CHESHIRE. By the late Lord DE TABLEY (Hon. J. BYRNE LEICESTER WARREN). Edited by SPENCER MOORE. With a Biographical Notice of the Author by Sir MOUNTSTUART GRANT DUFF. LONDON LONGMANS, GREEN, & CO. I WEE Ke vero toil Dy | OURN AEs Ok SCIENCE. “ To the solid ground Of Nature trusts the mind which builds for aye.” —WORDSWORTH. No. 1541, VOL. 60] THURSDAY, MAY 11, 1899. > [PRICE SIXPENCE. Registered as a Nev's SraD: er at the General Post Office. L ee Rights are Reserved. ae & CO. 8 8 GARDEN SUN- DIALS. bal © Sal : zs 7 [e) q N 2 S Z QR Site = Ve Ons aS) see = can ne! xX ais Q ate SN = By co. NEV TON cite hei TO THE QUEEN & GOVERNMENT, 3 FLEET STREET, LONDON. Sek THE NO. 1“ VICTOR " HAND CAMERA. This Camera carries twelve } plates in sheaths, which ff are changed ac- gM curately by a simple lever movement, which automati- registers |i] exposures made. The lens is an fF achromatic ot best quality with Iris Diaphragm. The shutter is arranged for time and instantane- ous exposures, and can be regu- lated at varying speeds. JAMES WOOLLEY, SONS & CO., LTD, VICTORIA BRIDGE, MANCHESTER. Complete Catalogue on application. > Price, covered in best quality Morocco, £1 15 0. DOUBLE-SURFACE CONDENSER (CRIBB’S PATENT). Large Condensing Surfaces. Small size of Condenser. Small weight, Great mee EQUAL TO A LIEBIG CONDENSER FIVE TIMES ITS SIZE. SOLE MAKERS of the Metal Condensers : JOHN J. GRIFFIN & SONS, LE 20-26 SARDINIA STREET, LONDON, W.C. IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST FREE. INVENTED AND MADE ONLY BY NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, 38 HOLBORN VIADUCT, E.C. Branches—45 CORNHIL1, E.C., and 122 REGENT STREET W, The Worstupfal Company Spectacle Makers. CERTIFICATION OF OPTICIANS. The next Examinations for the Diploma will be held at the- Northampton Institute on the 6th, 7th, and 8th of June next. The Syllabus can be obtained from Colonel T, Davies Sewell, F.R.A.S., Clerk of the Company, Guildhall, London, E.C. Applications for Examination should reach the CLERK not later than Saturday, 2oth May. BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. Principal—Miss ETHEL HURLBATT. -SESSION The Easter Half Term begins on Thursday, May 25. ENTRANCE SCHOLARSHIPS. One Arnott Scholarship in Science, Annual Value £48, and one Reid Scholarship in Art, annual value 30 Guineas, each tenable for three years, will be aw arded ¢ on the result of the Examination to be held at the College on June 27 and 2 Names to be sent to the PriNcirat not later than June 15. F. MABEL ROBINSON, Secretary. ROYAL INSTITUTION OF GREAT BRITAIN, 1898-94 ALBEMARLE STREET, PICCADILLY, W. Prof. Witt1aM J. Sotras, LL.D., D.Sc., F.R-S., will on Tuesday next, May 16th, at Three o'clock, begin a Course of Three Lectures on ‘‘ Recent Advances in Geology. Course, Half-a-Guinea. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. | Subse ription to this C NAT ORE Well-fitted LABORATORIES can be used for RESEARCH atany hour | convenient to Workers. Dark Room for PHOTOGRAPHIC and other | Work. yeimmersion for MICRO-PHOTOGRAPHY. Workshop for | making Apparatus. ELECTRIC MAINS, powerful Constant Currents. “” go Heathcote Street, Gray's Inn Road —ST. RESEARCH (Biological). - COLLABOR- ATEUR (or PUPIL) WANTED by Man of Science in important Use Laboratory. Terms by arra Z work to be shortly published | ment. Good Mathematics and Physics preferred.—Write ‘‘ Sc1eNcE,)’ NATURE. BEDFORD GRAMMAR SCHOOL. FIVE DEPARTMENTS. p Mirirary, TECHNICAL, Jt eighteen Head Master's Nominations to be competed ARY. H NIOR, PREPARATORY. | Cuassicat, Civit Fight Exhibitions for May 23. Apply SECRE [May 11, 1899 INDIAN GEOLOGICAL SURVEY. Required for the Geological Survey of India, a Specialist, who should have a thorough training in Field Geology, and experience in carrying out Geological Surveys, as well as in conducting economic inquiries in connection with Coal-fields. Candidates, under 4o years of age, are invited to apply to the Under- Secretary ofState, India Office, Whitehall, London, not later than the sth June, with Certificates of Qualifications : and of Age. The Salary of the Post is goo Rupees a month ; and the Appointment will be for a term of five years. Further particulars will be furnished on written application to the REVENUE SECRETARY, India Office, Whitehall. A. GODLEY, India Office, 3rd May, 1890. UNIVERSITY COLLEGE, LONDON. JODRELL PROFESSORSHIP OF ZOOLOGY. This Chair will be vacant by the resignation of Prof. Weldon at the close of the present Session. Applications, accompanied by such testimonials as Candidates may wish to submit, should reach the Secretary by Monday, June 5, 1899. Further information will be sent on application to the SECRETARY. The new Professor will enter on his duties in the October following. J. M. HORSBURGH, M,A., Secretary. SWANSEA MUNICIPAL TECHNICAL SCHOOL. G. S. TURPIN, M.A., D.Sc., Principal. Applications are invited for the Post of ASSISTANT LECTURER in MECHANICAL ENGINEERING. Candidates must have had Workshop experience and a Scientific training; : proved ability to teach would be a strong recommendation The Salary offered is £120 per annum. A Statement of Duties may be obtained on application from the SECRETARY OF THE SCHOOL. Applications, with one set of copies of testimonials, should be received not later than Wednesday, May 24th. L. COLLWYN LEWIS, Secretary. "BOROUGH OF SWAN SEA. INTERMEDIATE AND TECHNICAL SCHOOL FOR BOYS. An ASSISTANT MASTER will be required in September to teach Puysics (fHEoRericaAL and PRacricaL) and some MaTHEMATICS. Candidates must have had experience in teaching, and be well acquainted with Laboratory Work in Physics, as taught in Schools. The Salary offered is £150 per annum. Further particulars may be obtained on application from the SECRETARY. Applications, with one set of copies of testimonials, should be addressed tothe Heap Master, and should reach him not later than Wednesday, May 24th. Under-Secretary of State. L. COLLWYN LEWIS, Secretary. VICTORIA INSTITUTE, “WORCESTER. The Committee invite Applications for the HEADMASTERSHIP of the SCHOOL OF ART Candidates should possess special qualifications in Industrial Application of Art. The Headmaster will general direction of the Principal of Victoria Institute. 4200, rising to ; ). i testimonials should be sent, on or before Monday Applications and ) June 5, 1899, to the undersigned, from whom further particulars may be obtained. aq OM DUCKWORTH, Design and the work under the Yearly salary Sec ety: (W.R.) “UNIVERSITY OF “sT. “ANDREWS. The UNIVERSITY COURT OF ST. ANDREWS will, at a meeting to be held in the month of July, appoint an ADDITIONAL EXAMINER for Graduation in the subject of NATURAL SLORY. Applications, with testimonials, to be lodged by 21st June next with the undersigned, from whom further information ma ay be obtained. JNO. E. WILLIAMS, Secretary. St. Andrews, May, 1809 LONDON (ROYAL FREE HOSPITAL) | SCHOOL OF MEDICINE FOR WOMEN. APPLICATIONS invited for the POST of LECTURER in PHYSICS. Particulars on Square, W.C. are application to the SEcRETARY, 8 Hunter Street, Brunswick | PARTNER WANTED in a SCIENTIFIC MANUFACTURING BUSINESS, with £30¢ o. Would suit Scientific Man or Son; exceptional opening ; Capital wanted to enlarge the Business and carry cut the Orders in hand, and to enable the increasing demand to be met. Profits very large.—Address ‘*ScIENTIFIC,’ care of NaTuRrE Office A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. “© To the solid ground Of Nature trusts the mind which builds for aye.”—WORDSWORTH. No. 1542, VOL. 60] THURSDAY, MAY 18, 1899. [PRICE SIXPENCE. Ree as a Newspaper at the General Post Office.] [All Rights are Reserved. INDUCTION COILS. APPS’ PATENTED INDUCTION COILS are now manufactured concurrently by NEWTON & CO., 3 FLEET STREET, LONDON. ye HH wm room “xX” RAY “FOCUS” TUBES, 25s. FLUORESCENT SCREENS, 68s. and 90s. Complete Apparatus for Réntgen ‘‘ X”’ Rays, with Coils and Fluorescent Screens, &c. - - HIGHEST QUALITY: ONLY. Detatled List on Application. , BROWNING’S ‘*PANERGETIC” BINOCULAR OPERA, FIELD AND MARINE GLASS. Has 12 Lenses, gives a very large field of view, and exhibits objects with remarkable brightness and clearness. The ‘‘ Panergetic” is the best Binocular, for general use, made ; only its price has prevented it from being more widely known and used. Now it is reduced nearly half in price. The medium size in_ Black Enamel being £2 5s., and in Alum- inium £8, in best Cases complete. FULL PARTICULARS BY POST. JOHN BROWNING, 63 STRAND, LONDON, W.C. BEC FE’ NEW MICROSCOPE THE “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Eye-piece; Double Nose- piece, Two Object-glasses, 2/3” and 1/6”, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 R. SS J. 68 CORNHILL, No. 55. BECK, Ltd., LONDON, E.C. NEGRETTI & ZAMBRAS IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST(FREE. AND MADE ONLY BY INVENTED NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, 38 HOLBORN VIADUCT, E.C. Branches—45 CORNHILL, E.C., and 122 REGENT STREED, W. Xxil ROYAL INSTITUTION OF GREAT BRITAIN, ALBEMARLE STREET, PICCADILLY, W. Prof. L. C. Mraz, F.R.S., will on Thursday next, May 25th, at Three o'clock, begin a Course of Two Lectures on ‘‘ Water Weeds.”” Subscription for this Course, Half-a-Guinea. INDIAN GEOLOGICAL SURVEY. Required for the Geological Survey of India, a Specialist, who should have a thorough training in Field Geology, and experience in carrying out Geological Surveys, as well as in conducting economic inquiries in connection with Coal-fields. Candidates, under 40 years of age, are invited to apply to the Under- Secretary ofState, India Office, Whitehall, London, not later than the asth June, with Certificates of Qualifications and of Age. The Salary of the Post is g00 Rupees a month; and the Appointment will be for a term of five years. Further particulars will be furnished on written application to the REVENUE SECRETARY, India Office, Whitehall. A. GODLEY, Under-Secretary of State. India Office, 3rd May, 1890. SWANSEA MUNICIPAL TECHNICAL SCHOOL. G. S. TURPIN, M.A., D.Sc., Principal. Applications are invited for the Post of ASSISTANT LECTURER in MECHANICAL ENGINEERING. Candidates must have had Workshop experience anda Scientific training ; proved ability to teach would be a strong recommendation The Salary offered is £120 per annum. A Statement of Duties may be obtained on application from the SECRETARY OF THE SCHOOL. Applications, with one set of copies of testimonials, should be received not later than Wednesday, May 24th. L. COLLWYN LEWIS, Secretary. BOROUGH OF SWANSEA. INTERMEDIATE AND TECHNICAL SCHOOL FOR BOYS. An ASSISTANT MASTER will be required in September to teach Puysics (THEORETICAL and PRacTICAL) and some MATHEMATICS. Candidates must have had experience in teaching, and be well acquainted with Laboratory Work in Physics, as taught in Schools. The Salary offered is 4150 per annum. Further particulars may be obtained on application from the SECRETARY. Applications, with one set of copies of testimonials, should be addressed tothe Heap Master, and should reach him not later than Wednesday, May 24th. L. COLLWYN LEWIS, Secretary. UNIVERSITY COLLEGE, LONDON. JODRELL PROFESSORSHIP OF ZOOLOGY. This Chair will be vacant by the resignation of Prof. Weldon at the close of the present Session. Applications, accompanied by such testimonials as Candidates may wish to submit, should reach the Secretary by Monday, June 5, 1899. Further information will be sent on application to the SECRETARY. The new Professor will enter on his duties in the October following. J. M. HORSBURGH, M.A., Secretary. ~ UNIVERSITY OF ST. ANDREWS. CHAIR OF PATHOLOGY. In accordance with the terms of Ordinance No. 47 (St. Andrews, No. 6) of the Commissioners, under the Universities (Scotland) Act 1889, the University Court will appoint a PROFESSOR OF PATHOLOGY, who shall conduct Classes at Dundee qualifying for graduation in Medicine ; ‘the appointment to date from October 1, 1899. Applications, accompanied by twenty copies of testimonials, to be lodged by 21st JUNE next, with Mr. J. E. Witttams, Secretary of the University, from whom further information may be obtained. St. Andrews, May 1899. UNIVERSITY OF ST. ANDREWS. The UNIVERSITY COURT OF ST. ANDREWS will, at a meeting to be held in the month of July, appoint an ADDITIONAL EXAMINER for Graduation in the subject of NATURAL HISTORY, Applications, with testimonials, to be lodged by 21st June next with the undersigned, from whom further information may be obtained. JNO. E. WILLIAMS, Secretary. St. Andrews, May, 1899. RESEARCH. CHEMISTRY. PHYSICS. — BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. ysimmersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Constant Currents. —“ 'T.” 9 Heathcote Street, Gray's Inn Road. NATURE [May 18, 1899 BIRKBECK INSTITUTION, — Breams Buildings, Chancery Lane, E.C, Principat: G. ARMITAGE-SMITH, M.A. DAY AND EVENING CLASSES. UNIVERSITY OF LONDON.—Complete Day Courses for all the Examinations in Science, and Complete Evening Courses for all the Examinations for the Science, Arts, and Law Degrees. SCIENCE CLASSES in every Branch, with Practical Work. Well- equipped Laboratories for Chemistry, Physics, Biology, Botany, Geology, Mineralogy, and Metallurgy. CONJOINT BOARD : Lectures and Practical Work in Chemistry, Physics, Biology, and Practical Pharmacy. NEW TERM for Conjoint Board and Inter. M.B. Examinations has just commenced. Prospectus, Calendar (6d.), and Syllabuses of Classes on application to the Secretary. EGYPTIAN GOVERNMENT SCHOOLS. FIVE ASSISTANT MASTERS REQUIRED, to begin work in October, in Cairo Secondary School, under Ministry of Public Instruction. Masters to teach in English exclusively—one of them principally Physics and Chemistry, two of them principally Mathematics, and the two others principally English. Over three hundred boys. English Head Master. Teaching hours on an average, three daily—Fridays excepted. Summer vacation not less than two months annually. Graduates of Oxford or Cambridge preferred. Salary about £295 per annum (L. Eg. 288), rising to about £393. Civil Service Pension Scheme. Allowance for passage out to Egypt. ; : Z Applications, accompanied by copies only of testimonials, must be sent in before June 30, 1899, marked outside “* English Masterships,” and addressed to the SECRETARY-GENERAL, Ministry of Public Instruction, Cairo, Egypt, to whom Candidates may apply for further information. MUNICIPAL TECHNICAL SCHOOLS, PLYMOUTH. WANTED, an ASSISTANT MASTER (Undergraduate in Science preferred), mainly for School of Science work. Must have good teaching experience. Salary £roo per annum, rising by annual increments of £10 to 4120. Full particulars from T. W. BYFIELD, Secretary. RESEARCH (Biological). — COLLABOR- ATEUR (or PUPIL) WANTED by Man of Science in important work to be shortly published. Use Laboratory. Terms by arrange- ment. Good Mathematics and Physics preferred.—Write ‘‘ ScrENCE,” c/o NATURE. TUITION._ALL EXAMINATIONS —MEDICAL AND SCIENTIFIC. Well-fitted Laboratories.— **R.C.," 9 Heathcote Street, Mecklenburgh Square. PALAZARCTIC MOLLUSCA.— One of the largest Collections in Europe, containing many Types, together with an extensive Malacological Library, for Sale.—For particulars and price apply to ‘“*G. W.,” c/o of Goutp's Advertising Offices, 54 New Oxford Street. ‘ Sale by Huction. TUESDAY, MAY 30. . A VALUABLE COLLECTION OF BRI'tISH AND FOREIGN BIRDS AND EGGS. MR. J. C. STEVENS will Sell the above by Auction, at his Great Rooms, 38 King Street, Covent Garden, as above, at 12.30. s On view the Day prior, 10-4, and Morning of Sale, and Catalogues had. FREDK. JACKSON & Go. (Late MOTTERSHEAD & CO.), [44 CROSS STREET, MANCHESTER, Goods Entrance: 10 Half-Moon Street, LABORATORY FURNISHERS, Importers, Manufacturers, and Dealers in CHEMICAL AND PHYSICAL APPARATUS Of every Description. Fine Chemicals, Volumetric Solutions, Plain and Stoppered Bottles, AND EVERY LABORATORY REQUIREMENT. Illustrated Catalogue of Apparatus, with Price of Chemicals, free on application. Telegraphic Address—‘‘ APPARATUS, MANCHESTER.” Telephone Number—2038. Apparatus for estimation of sulphur in spent oxide. A WEEKLY ILEUSHRATED:) JOURNAL OF. SCIENCE. “To the solid g O; Nature trusts the mind which builds for aye.’ ryvouna >_-WORDSWORTH. z bo 43 PaviOllu: 60] ENOARNSIDAYY-, MAY 25; 1899. [PRICE SIXPENCE. Rezistered asa SESS at the General Post Office.] [All Rights are Reserved NEWTON FC eee | THE NO..1 “ TS ean CAMERA. SCIENTIFIC INSTRUMENT | MAKERS TO HER MAJESTY THE QUEEN AND THE GOVERNMEN' PHILOSOPHICAL INSTRU- MENT MAKERS BY SPECIAL APPOINTMENT TO THE Royat INSTITUTION OF GrEaT BritTAIn. Makers of every descrip- tion of OPTICAL and PHYSICAL APPARA- TUS of the highest class, for Colleges, Institutions, &e. Catalogue ot OPTICAL LANTERNS, PROJECTION APPARA- TUS, and SLIDES, 6¢. WIMSHURST ELECTRICAL MACHINES. Best Quality, 12 in., 70s. ; ; 18 in., 4610s. Multiple-Plate Machines, £20 to £150. jade for the Science and Art Depart- ment, and the Universities of Oxford, Cambridge, London, Sydney, N.S.W., McGill, Montreal, &c 3 FLEET STREET, TEMPLE BAR, LONDON, E.C. SHORT BEAM BALANCES. CHEAP, QUICK-ACTING, ACCURATE, KNIFE EDGES AND PLANES OF AGATE Compensating Stirrup Suspenders. To carry-200, 500 grammes. Price £7. £9 9s. ASSAY BALANCES. ALUMINIUM BEams. 5 Grammes in each Pan. ‘Indicate J; m.g. £10 10s. and £7. CHEMICAL BALANCE. ALuMINIUM BEam. New design Sliding Rider. Tocarry 100 250 grms. Indicates 5 “yo m. _ £8 15s. _ £10 one WRITE for BALANCE CATALOGUE JOHN J. GRIFFIN & SONS, E 20-26 SARDINIA STREET, LONDON, W.C. This Caner carries twelve +) pillaiteismin sheaths, which are changed ac- curately by a simple lever movement, which automati- registers also cally the made. exposures The lens is an achromatic ot quality with Diaphragm. The shutter arranged for time instantane- best Iris and ous exposures, and can be regu- lated at varying speeds. JAMES WOOLLEY, SONS & CO., LTD., VICTORIA BRIDGE, MANCHESTER. Complete Catalogue on application. £1 15 0.5 Price, covered in best quality Morocco IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST FREE. INVENTED AND MADE ONLY BY NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, 38 HOLBORN VIADUCT, E.C. Branches— 45 CORNHILI, E.C., and 122 REGENT STREET, W. XXX NAT ORL [| May 25, 1899 BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. Principal—Miss ETHEL HURLBATT. SESSION 1898-9. The Easter Half Term begins on Thursday, May 2s. ENTRANCE SCHOLARSHIPS. One Arnott Scholarship in Science, Annual Value £48, and one Reid Scholarship in Art, annual value 30 Guineas, each tenable for three years, will be awarded on the result of the Examination to be held at the College ‘ on June 27 and 28. Names to be sent to the PriNciPAL not later than June 15. F. MABEL ROBINSON, Secretary. THE ELECTRICAL GENERAL ENGINEERING COLLEGE, EXPERIMENTAL ENGINEERING WORKS, 2 and 4 PENYWERN ROAD, EARL’S COURT, LONDON, S.W., (rains Students for Electrical, Mechanical and Mining Engineering. Develops Electrical and Mechanical Patents. Constructs Experimental and Special Machinery and Models to Specification. UVERNM RE LONDON BRANCH at a 24 CHANCERY LANE, W.C. Tuition by JOHN GIBSON, M.A. (First Class, Camb.), and G. LOLY, B.A (First Class, London), for all Public Examinations. Special Instruction in Scientific Agriculture for successful practical Agriculture and Forestry in the British Islands or the Colonies; also in Geology, Botany, &c., Practical, Chemical, and Physical Laboratories. The ‘‘State Corre- spondent” and Higher Examination Journal gives up-to-date particulars of all the leading C.S. and other Examinations. Price 24d., post free. Prize of One Guinea for competition each month; Special Prize of Five Guineas each June and December. RESEARCH. CHEMISTRY. PHYSICS. — BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. yxsimmersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Constant Currents. —‘‘T. "9 Heathcote Street, Gray's Inn Road. WALSALL SCIENCE AND ART INSTITUTE. Wanted for September next :— 1. A Teacher of Evening Classes in Chemistry and Metallurgy. Salary, £120 per annum. . i . A Teacher of Evening Classes in Physics and Mathematics. Salary, 4120 per annum. The selected Candidates will be expected to devote their chief attention to the work ; but a limited number of private appointments will be allowed. 3. A Second Art Master to take charge of the Day Classes and to assist in the Evening Work. Salary, £150 per annum. Copies of the duties will be forwarded on receipt of a stamped and addressed envelope. Apply, stating age and qualifications, and forwarding o¢ #zove than three testimonials, not later than Monday, June 12th, to JOHN TURNER, Director of Technical Instruction. INDIAN GEOLOGICAL SURVEY. Required for the Geological Survey of India, a Specialist, who should have a thorough training in Field Geology, and experience in carrying out Geological Surveys, as well as in conducting economic inquiries in connection with Coal-fields. Candidates, under 40 years of age, are invited to apply tu the Under- Secretary ofState, India Office, Whitehall, London, not later than the r5th June, with Certificates of Qualifications and of Age. The Salary of the Post is goo Rupees a month; and the Appointment will be for a term of five years. Further particulars will be furnished on REVENUE SECRETARY, India Office, Whitehall. A. GODLEY, Under-Secretary of State. written application to the India Office, 3rd May, 1899. THE YORKSHIRE COLLEGE, LEEDS. DEPARTMENT OF AGRICULTURE, Applications for the Appointment of a LECTURER on AGRI- CULTURAL CHEMISTRY, at a stipend of £250 a year, will be received upto June 26th, 1899, by the REGISTRAR OF THE COLLEGE, from whom Jurther particulars of the Appointment may be obtained. EGYPTIAN GOVERNMENT SCHOOLS. FIVE ASSISTANT MASTERS REQUIRED, to begin work in October, in Cairo Secondary School, under Ministry of Public Instruction. Masters to teach in English exclusively—one of them principally Physics and Chemistry, two of them principally Mathematics, and the two others principally English. Over three hundred boys. English Head Master. ‘Leaching hours on an average, three daily—Fridays excepted. Summer vacation not less than two months annually. Graduates of Oxford or Cambridge preferred. Salary about £295 per annum (L. Eg. 288), rising to about £393. Civil Service Pension Scheme. Allowance for passage out to Egypt. Applications, accompanied by copies only of testimonials, must be sent in before June 30, 1899, marked outside ‘‘ English Masterships,”’ and addressed to the SECRETARY-GENERAL, Ministry of Public Instruction, Cairo, Egypt, to whom Candidates may apply for further information. COUNTY BOROUGH OF WEST HAM. Applications are invited for the following Appointments on the Teaching Staff of the Municipal Technical Institute :— ASSISTANT LECTURER in MATHEMATICS (41s0 per annum), DEMONSTRATOR in ENGINEERING (£100 per annum). The above are commencing salaries. Full particulars can be obtained by sending a fully addressed foolscap envelope to the Principat, Municipal Technical Institute, Romford Road, West Ham, E., before June 29th, 1899. By order of the Council, FRED. E. HILLEARY, Town Clerk. Town Hall, West Ham, E., May 18th, 1899. UNIVERSITY COLLEGE, LONDON. JODRELL PROFESSORSHIP OF ZOOLOGY. This Chair will be vacant by the resignation of Prof. Weldon at the close of the present Session. Applications, accompanied by such testimonials as Candidates may wish to submit, should reach the Secretary by Monday, June 5s, 1899. Further information will be sent on application to the SECRETARY. ‘The new Professor will enter on his duties in the October following. J. M. HORSBURGH, M.A., Secretary. TUITION.—_ALL EXAMINATIONS —MEDICAL AND SCIENTIFIC. Well-fitted Laboratories.— “*R-C.," 9 Heathcote Street, Mecklenburgh Square. From CHAPMAN & HALL’S NEW BOOKS. ANIMALS IN MOTION. An Electro - photographic Investigation of consecutive Phases of Progressive Movements. _ Illus- trated with 95 full-page Photo-Mezzotint Engravings, reproduced from the Original Negatives, and containing more than 1600 half-tone figures of Horses, Dogs, Elephants, Lions, and other animals, while engaged in Walking, Galloping, Leaping, or some other act of motion, and of Birds while flying. By EADWEARD MUYBRIDGE. Oblong, 20s. net. TRUE TALES OF THE INSECTS. by L. N. BADENOCH, Author of ‘*Romance of the Insect World.” With Frontispiece and 43 Illustrations by Marcarer J. D. BapEeNnocn. Large crown 8vo, res. The S/ectatory says :—‘‘ One of the most interesting books of popular entomology that we have seen for some time.”’ The Daily Telegraph says:—‘'Excellently written, and brings the wonders and possibilities of the higher entomology very clearly home to us." CHAPMAN & HALL, Lrp., Lonpon. ANNALS OF BOTANY. The JUNE Number (Vol. XIII., No. I.), containing the following Papers, will be issued shortly ; price 14s. :— Snow, J. W.—Pseudo-Pleurococcus, Nov. gen. (With Plate XI.). Warp, H. M.—Thames Bacteria, IfI. (With Plates XII.-XIV.). " DarsisHireE, O. V.—On Actinococcus and Phyllophora. (With Plate XV. and Seven Figures in the Text). a Dixon, H. H.—The Possible Function of the Nucleolus in Heredity. Lanc, W. H.—The Prothallus of Lycopodium clavatum, L. (With Plates XVI. and XVII.). LONDON : HENRY FROWDE, AMEN CORNER, E.C. OXFORD: CLARENDON PRESS DEPOSITORY, 116 HIGH STREET. Sale by Huction. TUESDAY, MAY 30. y A VALUABLE COLLECTION OF BRITISH AND FOREIGN BIRDS AND EGGS. MR. J. C. STEVENS will Sell the above by Auction, at his Great Rooms, 38 King Street, Covent Garden, zs above, at 12.3c. 7 On view the Day prior, 10-4, and Morning of Sale, and Catalogue had. PO WRE KL Y WeeUS@VvAD HD [OURNAIE OK SCIENCE: “ To the soltd ground O) Nature trusts the mind which burlds for aye.” —WORDSWORTH. No. 1544, VOL. 60] THR SAW. UNE ay sisoe: [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] {All Rights are Reserved. -SUN-DIALS ON PEDESTALS. ___ BROWNING’S vase oreuan | “PANERGETIC” BINOCULAR HORIZONTAL SUN-DIAL, | i425 ee . on oo ihe i es and exhibits objects with remarkable brightness and clearness. i ii h Complete on ° TERRA-COTTA.PEDESTAL. 12” Diameter, £6 10s. NEWTON & CO., OPTICIANS TO THE QUEEN | ite AND GOVERNMENT, : 3 FLEET STREET. LONDON. Full Descriptive Price List SY ow teewe _JQHN BROWNING, 63 STRAND, LONDON, W.C. =o = NEGRETTI & ZAMBRAS The ‘‘ Panergetic” is the best Binocular, for general. use, made; only Its price has prevented it from being more widely known and used. Now it is reduced nearly half in price. The medium size in Black Enamel being £2 5s., and in Alum- NE UU usec : inium £8, in best Cases BF SEES a complete. FULL PARTICULARS BY POST. NEW MICROSCOPE | a IMPROVED Te Pim, SELF-RECORDING “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, RAIN GAUGE. One Eye-piece; Double Nose- DESCRIPTIVE piece, Two Object-glasses, 2/3” PRICE LIST and 1/6”, adjusted to be in POST FREE. about focus, and the whole packed in polished Mahogany Case, £6:8:6 INVENTED AND MADE ONLY BY NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, R. & J. BECK, Ltd., 38 HOLBORN VIADUCT, E.C. 68 CORNHILL, LONDON, E.C. Branches—45 CORNHILL, E.C., and 122 REGENT STREET, W. XXXVIL INZLTAO LL [June 1, 1899 NOTICE. N Ae Oe i Of THURSDAY, JUNE §, will contain the INDEX Its price will be ONE SHILLING. Advertisements for Number must reach the Publishers not later than by the morning of VoLtuME LIX. intended insertion in this WEDNESDAY, JUNE 7. “NATURE” OFFICE, Sia IMeASTR TaN ier S ia O)laiReEs selec IV Ven Gre BIRKBECK INSTITUTION, — Breams Buildings, Chancery Lane, E.C. DAY AND EVENING CLASSES. UNIVERSITY OF LONDON.—Complete Day Courses for all the Examinations in Science, and Complete Evening Courses for all the Examinations for the Science, Arts, and Law Degrees. SCIENCE CLASSES in every Branch, with Practical Work. Well- equipped Laboratories for Chemistry, Physics, Biology, Botany, and Metallurgy. LECTURES on Political Economy, Commercial Geography, Common Law, Bankruptcy, Equity and Conveyancing, Logic, Psychology, and Ethics. CLASSES in Languages, Literature, English and Commercial Subjects. CONJOINT BOARD : Lectures and Practical Work in Chemistry, Physics, Biology, and Practical Pharmacy. Prospectus, Calendar (6d.), and Syllabuses of Classes on application to the Secretary. ENGINEERING AND CHEMISTRY. CITY AND GUILDS OF LONDON INSTITUTE. SESSION 1899-1900. The Courses of Instruction at the Institute's CentTraL TECHNICAL COLLEGE (Exhibition Road) are for Students not under 16 years of age; those at the Institute’s TECHNICAL COLLEGE, Finspury, for Students not under 14 years ofage. The Entrance Examinations to both Colleges are heldin September, and the Sessions commence in October. Particulars of the Entrance Examinations, Scholarships, Fees, and Courses of Study, may be obtained from the respective Colleges, or from the Head Office of the Institute, Gresham College, Basinghall Street, E.C. CITY AND GUILDS CENTRAL TECHNICAL COLLEGE. (Exursition Roap, S.W.) A College for higher Technical Instruction for Students not under 16 pre- paring to become Civil, Mechanical, or Electrical Engineers, Chemical and other Manufacturers, and Teachers. Fees for a full Associateship Course, 425 per Session. Professors :— Civil and Mechanical Engineering W.C Unwin, F.R.S., M.Inst.C.E. Filech stn ion eaHee oe { W. E. Ayrton, F.R.S., Past Pres. LLECTIICA mugineering eee \ Inst. EE. jH. E. ArmstronG, Ph.D., LL.D., aed F.R.S., Dean of the College for the \ Session. Mechanics and Mathematics O. Hewrici, Ph.D., LL.D., F.R.S. CITY AND GUILDS TECHNICAL COLLEGE, FINSBURY. (LEonarD STREET, City Roan, E.C.) Provides Courses of Intermediate Instruction for Day Students not under tq years of age, preparing to enter Engineering and Chemical Industries. Fees, £15 per Session. Professors :— Physics and Electrical Engineering { S. (eeeeer iecalas x S. Chemistry Mechanical Engineering and\ r NIST atic = a) W.E. Dacsy, M.A., B.Sc., M.I.M.E Chemistry R. Mevpora, F.R.S., F.I.C. JOHN WATNEY, Hon. Secretary. City and Guilds of London Institute, Gresham College, Basinghall Street, E.C. “ROYAL GEOGRAPHICAL SOCIETY. The ANNIVERSARY MEETING will be held (by permission of the Senate) in the Hall of the University of London, Burlington Gardens, W., on Monday, June 5, at 3 p.m., Sir Clements Markuam, K.C.B., F.R.S., President, in the chair. During the Meeting the Council and Officers will be elected for the ensuing year, the President will give his Address, and the Gold Medals and other Awards of the Society will be presented. The ANNUAL DINNER of the Society will be held on the evening of the Anniversary Meeting, at the Hétel Métropole, Whitehall Rooms, Whitehall Place, S.W., at7 for 7.30pm. Dinner Charge £1 1s. Friends of Fellows are admissible to the Dinner. “WALSALL SCIENCE AND ART INSTITUTE. Wanted for September next :— 1. A Teacher of Evening Classes in Chemistry and Metallurgy. Salary, £120 per annum. A Teacher of Evening Classes in Physics and Mathematics. Salary, 4120 per annum. The selected Candidates will be expected to devote their chief attention to the work ; but a limited number of private appointments will be allowed. . A Second Art Master to take charge of the Day Classes and to assist in the Evening Work. Salary, £150 per annum. Copies of the duties will be forwarded on receipt of a stamped and addressed envelope. Apply, stating age and qualifications, and forwarding ot ove than three testimonials, not later than Monday, June rzth, to JOHN TURNER, Director of Technical Instruction. EGYPTIAN GOVERNMENT SCHOOLS. FIVE ASSISTANT MASTERS REQUIRED, to begin work in October, in Cairo Secondary School, under Ministry of Public Instruction. Masters to teach in English exclusively—one of them principally Physics and Chemistry, two of them principally Mathematics, and the two others principally English. Over three hundred boys. English Head Master. ‘Leaching hours on an averege, three daily—Fridays excepted. Summer vacation not less than two months annually. Graduates of Oxford or Cambridge preferred. Salary about £295 per annum (L. Eg. 288), rising to about £393. Civil Service Pension Scheme. Allowance for passage out to Egypt. Applications, accompanied by copies only of testimonials, must be sent in befure June 30, 1899, marked outside ‘‘ English Masterships,” and addressed to the SECRETARY-GENERAL, Ministry of Public Instruction, Cairo, Egypt, to whom Candidates may apply for further information. COUNTY BOROUGH OF WEST HAM. Applications are invited for the following Appointments on the Teaching Staff of the Municipal Technical Institute :— ASSISTANT LECTURER in MATHEMATICS (£150 per annuum). DEMONSTRATOR in ENGINEERING (£100 per annum). The above are commencing salaries. Full particulars can be obtained by sending a fully addressed fo Iscap envelope to the Principat, Municipal Technical Institute, Romford Road, West Ham, E., before June 19th, 1899. By order of the Council, FRED. E. HILLEARY, Town Clerk. Town Hall, West Ham, E., May r8th, 1899. UNIVERSITY COLLEGE OF NORTH WALES. (A CONSTITUENT COLLEGE OF THE UNIVERSITY OF WALES.) Applications are invited for the Post of ASSISTANT LECTURER IN AGRICULTURE. Salary 4120. Competent knowledge of Forestry desirable but not essential. Ability to Lecture in Welsh will be considered an additional qualification. For particulars apply to the undersigned, to whom applications must be sent not later than June 2oth. J. E. LLOYD, M.A., Secretary and Registrar. Bangor, June ist, 1899. MUNICIPAL TECHNICAL SCHOOLS, PLYMOUTH. WANTED, an ASSISTANT MASTER (Undergraduate in Science preferred), mainly for School of Science work. Must have good teaching experience. Salary £100 per annum, rising by annual increments of £10 to 4120. Full particulars from DEPARTMENT OF AGRICULTURE, Applications for the Appointment of a LECTURER on AGRI- CULTURAL CHEMISTRY, at a stipend of £250 a year, will be received up to June 26th, 1899, by the REGISTRAR OF THE COLLEGE, from whom further particulars of the Appointment may be obtained. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room fgr PHOTOGRAPHIC and other Work. j:immersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Constant Currents. —‘ fT. "' 9 Heathcote Street, Gray's Inn Road. INDEX NUMBER. we WIE EK IG Y; ILLUSTRATED “JOURNAL OFWSCIENCE- ‘* To the solid ground Of Nature trusts the mind which builds for aye.’ °>—WORDSWORTH. No. 1545, VOL. 60] THURSDAY, JUNE 8, 1899. PRICE ONE SHILLING. General Po: ot Ofinezl) Registered as a Newspaper at the NEWTON & CO,, Scientific Fnustrument Makers to the Queen. 3 FLEET STREET, LONDON. CHEAP ASTRONOMICAL TELESCOPES. From £5. I/lustrated Catalogue 4 stamps. GRIFFINS NEW FORM OF APPARATUS For the ABSOLUTE EXPANSION OF SOLIDS (Weedon’s Patent). fone great merit in the design of this ApoMane is that itis a cls Mechanical method, and does not depend at all upon Optical methods ei magnification that so frequently are a difficulty in early Practical Physic we ork. The measurement reduces itself to the readings of two Micrometer Sere "A DIRECT MECHANICAL METHOD. ABSOLUTE READINGS OBTAINED. SIMPLEST DESIGN. Write for Particulars and Specimen Curves obtained. SOLE MAKERS: JOHN J. GRIFFIN & SONS, LE 20-26 SARDINIA STREET, LONDON, W.C. ’ ‘Victoria Phow ati ean Rights are Reserved. From £1 1s. to £10 10s. HICH GRADE CAMERAS AT POPULAR PRICES. PHOTO- GRAPHIC CATALOGUE BACKGROUNDS ON APPLICATION. JAMES WOOLLEY, SONS & CO., Lt. VICTORIA BRIDGE, MANCHESTER, NEGRETTI & ZAMBRA'S IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST FREE. INVENTED AND MADE ONLY BY NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, 38 HOLBORN VIADUCT, E.C. xlvi NATURE [JUNE 8, 1899 BALLIOL COLLEGE, CHRIST CHURCH, AND TRINITY COLLEGE, OXFORD. NATURAL SCIENCE SCHOLARSHIPS AND EXHIBITIONS. A Combined Examination for Natural Science Scholarships and Exhibi- tions will be held by the above Colleges, beginning on TUESDAY, NOVEMBER 21, 1899. Three Scholarships and Two Exhibitions will be offered, the Scholarships being worth £80 a year. The Subjects for Examination will be Physics, Chemistry, and Biology ; but Candidates will not be expected to offer themselves in more than two of these. Particulars may be obtained by application to Christ Church, Oxford. A. VERNON HARCOURT. ~ WALSALL SCIENCE AND ART INSTITUTE. Wanted for September next :— 1. A Teacher of Evening Classes in Chemistry and Metallurgy. Salary, £120 per annum. 2. A Teacher of Evening Classes in Physics and Mathematics. Salary, 4120 per annum. The selected Candidates will be expected to devote their chief attention to the work ; but a limited number of private appointments will be allowed. 3. A Second Art Master to take charge of the Day Classes and to assist in the Evening Work. Salary, £150 per annum. Copies of the duties will be forwarded on receipt of a stamped and addressed envelope. Apply, stating age and qualifications, and forwarding xo¢ #zove than three testimonials, not later than Monday, June 12th, to JOHN TURNER, Director of Technical Instruction. ‘UNIVERSITY COLLEGE OF NORTH WALES. (A CONSTITUENT COLLEGE OF THE UNIVERSITY OF WALES.) Applications are invited for the Post of ASSISTANT LECTURER IN AGRICULTURE. Salary 4120. Competent knowledge of Forestry desirable but not essential. Ability to Lecture in Welsh will be considered an additional qualification. For particulars apply to the undersigned, to whom applications must be sent not later than June 2oth. J. E. LLOYD, M.A., Secretary and Registrar. Bangor, June rst, 1899. COUNTY BOROUGH OF WEST HAM. Applications are invited for the following Appointments on the Teaching Staff of the Municipal Technical Institute :— ASSISTANT LECTURER in MATHEMATICS (4150 per annum). DEMONSTRATOR in ENGINEERING (100 per annum). The above are commencing salaries. Full particulars can be obtained by sending a fully addressed foolscap envelope to the Principat, Municipal Technical Institute, Romford Road, West Ham, E., before June 19th, 1899. By order of the Council, FRED. E. HILLEARY, Town Clerk. Town Hall, West Ham, E., May 18th, r8qo. BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. Principal—Miss ETHEL HURLBATT. ENTRANCE SCHOLARSHIPS. One Arnott Scholarship in Science, Annual Value £48, and one Reid Scholarship in Art, Annual Value 30 Guineas, each tenable for three years, will be awarded on the result of the Examination to be held at the College on June 27 and 28. Names to be sent to the PRINCIPAL not later than June 15. F. MABEL ROBINSON, Secretary. BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. The LECTURESHIP in BACTERIOLOGY will be Vacant at the end of this Session. Applications, together with thirteen copies of Testimonials, must be sent by Monday, June 19, to the SECRETARY at the College, from whom all information may be obtained. F. MABEL ROBINSON, Secretary. BATTERSEA POLYTECHNIC, BATTERSEA PARK ROAD, S.W. The Governing Body require the Services of an ASSISTANT SCIENCE MASTER for Day School. For particulars send stamped and addressed envelope to the SECRETARY not later than June 14. B.A., PRELIMINARY SCIENTIFIC, B.Sc., and all other EXAMS. QUERNMORE. London Branches—(1) 24 CHANCERY LANE, W.C.; (2) 115 EBURY STREET, EATON SQUARE, S.W. Special Preparation by JOHN GIBSON, M.A. (First Class, Cambridge), and G. LOLY, B.A. (First Class, London), assisted by large Staff of Specialist Tutors. Practical Laboratories. Write for particulars to Messrs. Gisson & Lory, 24 Chancery Lane, W.C. THE ELECTRICAL AND GENERAL ENGINEERING COLLEGE, EXPERIMENTAL ENGINEERING WORKS, 2 and 4 PENYWERN ROAD, EARL’S COURT, LONDON, S.W., Trains Students for Electrical, Mechanical and Mining Engineering. Develops Electrical and Mechanical Patents. Constructs Experimental and Special Machinery and Models to Specification. ROYAL TECHNICAL INSTITUTE, SALFORD. PRINCIPAL W. WILSON, M.A. WANTED, an ASSISTANT LECTURER IN PHYSICS, with attainments in Mathematics. Salary, £100 per annum. Further particulars and forms of application may be obtained up to the 24th inst. upon application. RICHARD MARTIN, Secretary. June 6, 1899. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. jsimmersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Constant Currents. — T. "9 Heathcote Street, Gray’s Inn Road. MUNICIPAL TECHNICAL SCHOOLS, PLYMOUTH. WANTED, an ASSISTANT MASTER (Undergraduate in Science preferred), mainly for School of Science work. Must have good teaching experience. Salary 4100 per annum, rising by annual increments of £10 to 4120. Full particulars from T. W. BYFIELD, Secretary. TUITION._ALL EXAMINATIONS —MEDICAL AND SCIENTIFIC. Well-fitted Laboratories.— “*R.C.,” 9 Heathcote Street, Mecklenburgh Square. For Photography, Unsurpassed for fine definition. (COOKE TAYLOR, TAYLOR, & HOBSON, Slate Street Works, Leicester; and18 Berners Street, London, W. OPTICAL & SCIENTIFIC INSTRUMENTS, Spectrometers, Spectroscopes, Goniometers, Cathetometers, Optical Benches, &c., &c. Instruments for special purposes constructed to Clients own designs. Price List on application. W. WILSON (formerly Foreman at Messrs. ELLIOTT BRos.), 56 Crogsland Road, Chalk Farm, London, N.W. ContTrRAcTOoR TO H.M. GOVERNMENT. Sale by Huction, TUESDAY NEXT. A COLLECTION OF SHELLS FORMED BY A. W. LANGDON, Eso., M.A. MR. J. C. STEVENS will Sell the above by Auction, at his Great Rooms, 38 King Street, Covent Garden, as above, at 12.30 precisely. ‘ On view the Day prior, 10-4, and Morning of Sale, and Catalogues had THE LATE enV EK LY (eS Real DD! LOURNAILY OE SCIENCE. “© To the solid ground Of Nature trusts the mind which builds for aye.” —WORDSWORTH. No. 1546, VOL. 60] PEROHRS IDA, JUNE 15, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] NEWTON & covs NEW SCIENTIFIC INSTRUMENT FACTORY. | WE beg to announce that owing to increase of business | we have found it necessary to start a New Factory at i LIDGE JAMES STREET, W.c. where our well known ‘* Apps-Newton ” Multiple-plate Wimshurst Electrical Machines for work and Wireless Telegraphy will in future be manufactured, as well as the Scientific Instruments and Apparatus which we now make so largely. Our Optical Lanterns will still continue to be manufactured at-our Fleet Street workshops, and. the Lantern Slides at our Dalston and Islington works as heretofore. The different floors of the New Factory have been carefully arranged for securing a large output, and Electric Motive Power is being fitted to the machine tools, so that we shall hope to execute orders more expeditiously in future ; and every effort will be made to sustain and improve the reputation of the Firm for thoroughly sound and accurate: Wi orkmanship. NEw Ton & Co., Makers to the Queen, the Prince of Wales, and the Government, 38 FLEET STREET, LONDON, E.C. BEC FE’ NEW MICROSCOPE THE “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Eye-piece; Double Nose- piece, Two Object-glasses, 2/3” and 1/6”, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 R. & J. No. 55. BECK, Ltd., 68 CORNHILL, LONDON, E.C. Induction Coils and | X-Re Ay Philosophical [All EER S are Reserved. BROWNINQG’S ‘*PANERGETIC” BINOCULAR OPERA, FIELD AND MARINE GLASS. Has 12 Lenses, gives a very large field of view, and exhibits objects with remarkable brightness and clearness. The ‘‘ Panergetic” is the best Binocular, for general use, made; only its price has’ prevented it from being more widely known and used. Now it is reduced nearly half in price. The medium size in Black Enamel being £2 5s., and in Alum. inium £8, in best Cases complete. FUEL PARTICULARS BY POST. ~ JOHN BROWNING, 63 STRAND, LONDON, W.C. NEGRETTI & ZAMBRAS IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST FREE. INVENTED AND MADE -ONLY BY N EGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Teen. 38 HOLBORN VIADUCT, E.C. Branches—45 CORNHILL, E.C., and 122 REGENT STREET, W liv NATURE [JUNE 15, 1899 INTERNATIONAL CONGRESS OF WOMEN. (CONVENED BY THE INTERNATIONAL COUNCIL OF WOMEN.) WESTMINSTER TOWN HALL, JUNE 26th to JULY ath. Papers will be presented by experts on Education, Professions for Women, Legislative and Industrial Questions, Political and Social Work, INTERNATIONAL CONGRESS OF WOMEN. President: COUNTESS OF ABERDEEN. Tickets of Membership of the whole Congress, 75. 6d., to be obtained from Miss TERESA WILSON, Hon. Sec. International Council of Women, 36 Victoria Street, S.W. INTERNATIONAL CONGRESS OF WOMEN. SCIENCE SECTION. Westminster Town Hall, Thursday, June 29th, 10.30 a.m. THE WORK OF WOMEN IN THE PHYSICAL AND BIOLOGICAL SCIENCES. INTERNATIONAL CONGRESS FUND. Donations for the entertainment of Foreign Guests and for publication of the 7yazsactions, will be gratefully acknowledged by Mrs. BeproRD Frnwick, Hon, Treasurer, 20 Upper Wimpole Street, London, W. ENGINEERING AND CHEMISTRY. CITY AND GUILDS OF LONDON INSTITUTE. SESSION 1899-1900. The Courses of Instruction at the Institute's CENTRAL TECHNICAL CoLLeGE (Exhibition Road) are for Students not under 16 years of age; those at the Institute's TeEcHNICAL COLLEGE, Finspury, for Students mot under rq years ofage. The Entrance Examinations to both Colleges are held in September, and the Sessions commence in October. Particulars of the Entrance Examinations, Scholarships, Fees, and Courses of Study, may be obtained from the respective Colleges, or from the Head Office of the Institute, Gresham College, Basinghall Street, E.C. CITY AND GUILDS CENTRAL TECHNICAL COLLEGE. (ExHIBITION Roap, S.W.) A College for higher Technical Instruction for Students not under 16 pre- paring to become Civil, Mechanical, or Electrical Engineers, Chemical and other Manufacturers, and Teachers. Fees for a full Associateship Course, 425 per Session. Professors :— Civil and Mechanical Engineering W.C. Unwin, F.R.S., M.Inst.C.E. (ee E. Ayrton, F.R.S., Past Pres. Inst. E.E. jH. E. Armstronc, Ph.D., LL.D., Chemistry Sp 5 0 «. 4 F.R.S., Dean of the College for the \ Session: Mechanics and Mathematics O. Henrici, Ph.D., LL.D., F.R.S. CITY AND GUILDS TECHNICAL COLLEGE, FINSBURY. (Leonarp Street, City Roap, E.C.) Provides Courses of Intermediate Instruction for Day Students not under <4 years of age, preparing to enter Engineering and Chemical Industries. fees, £r5 per Session. Professors :— S. P. THompson, D.Sc., F.R.S. (Principal of the College.) £lectrical Exgineering ‘Physics and Electrical Engineering { Mechanical Exgineering and\w ow Darpy. M.A.. B.Sc., M.I.M.E Mathematics ste on ove Bae Sr age? > ae race Chemistry R. MEvpora, F.R.S., F.I.C. JOHN WATNEY, Hon. Secretary. City and Guilds of London Institute, Gresham College, Basinghall Street, E.C. LONDON (ROYAL FREE HOSPITAL) SCHOOL OF MEDICINE FOR WOMEN, 8 Hunter Street, Brunswick Square, W.C. Applications are invited for the Posts of LECTURER on BIOLOGY and LECTURER on PUBLIC HEALTH. _ Applications to be sent in by June 2zst. SECRETARY OF THE SCHOOL. Particulars on application to the BIRKBECK INSTITUTION, — Breams Buildings, Chancery Lane, E.C. DAY AND EVENING CLASSES. UNIVERSITY OF LONDON.—Complete Day Courses for all the Examinations in Science, and Complete Evening Courses for all the Examinations for the Science, Arts, and Law Degrees. SCIENCE CLASSES in every Branch, with Practical Work. Well- equipped Laboratories for Chemistry, Physics, Biology, Botany, and Metallurgy. LECTURES on Political Economy, Commercial Geography, Common Law, Bankruptcy, Equity and Conveyancing, Logic, Psychology, and Ethics. CLASSES in Languages, Literature, English and Commercial Subjects. CONJOINT BOARD : Lectures and Practical Work in Chemistry, Physics, Biology, and Practical Pharmacy. Prospectus, Calendar (6d.), and Syllabuses of Classes on application to the Secretary. NORTHAMPTON INSTITUTE, CLERKENWELL, LONDON, E.C. The following appointments are vacant : PHYSICAL LABORATORY ASSISTANT, for Optical work, one evening per week, 415 per Session. PHYSICAL LABORATORY ASSISTANT, for Electrical work, two evenings per week, £30 per Session. Particulars of any of the above appointments can be obtained by intend- ing candidates on application to the PRINCIPAL. Applications for the appointments should be received not later than noon on Monday, June 26, 1899. R. MULLINEUX WALMSLEY, D.Sc., Principal. UNIVERSITY COLLEGE OF NORTH WALES. (A CONSTITUENT COLLEGE OF THE UNIVERSITY OF WALES.) Applications are invited for the Post of ASSISTANT LECTURER IN AGRICULTURE. Salary 4120. Competent knowledge of Forestry desirable but not essential. Ability to Lecture in Welsh will be considered an additional qualification. For particulars apply to the undersigned, to whom applications must be sent not later than June 2oth. J. E. LLOYD, M.A., Secretary and Registrar. Bangor, June 1st, 1899. BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. The LECTURESHIP in BACTERIOLOGY will be Vacant at the end of this Session. ; ‘ i P Applications, together with thirteen copies of Testimonials, must be sent by Monday, June 19, to the SECRETARY at the College, from whom all information may be obtained. F. MABEL ROBINSON, Secretary. CITY OF BIRMINGHAM. MUNICIPAL TECHNICAL SCHOOL. The Corporation require the Services, in September next, of a LEC- TURER and DEMONSTRATOR in ELECTRICAL ENGINEER- ING and ALLIED SUBJECTS. Salary, 4125 per annum. : Full particulars and form of application will be forwarded on receipt of a stamped addressed foolscap envelope. x GEO. MELLOR, Secretary. Offices of the School, Suffolk Street, 7th June, 1899. | §$T. BARTHOLOMEW’S MEDICAL SCHOOL. The Post of ASSISTANT DEMONSTRATOR of CHEMISTRY will be vacant at the end of the Summer Session. Full particulars can be obtained from the undersigned, to whom all applications must be forwarded on or before Saturday, 8th July. JAMES CALVERT, M.D., Warden. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. p:immersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Constant Currents. —T." g Heathcote Street, Gray's Inn Road. A WEEKLY ILLUSTRATED JOURNAL. OF SCIENCE. “< To the solid ground Of Nature trusts the mind which builds Sor aye. Ww ORDSWORTH. NO. 1547, VOL. 60] THURSDAY, JUNE 22,, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] le RIES are Reserved. | ‘Victoria’ ato Outhes _ From £1 1s to £10 10s. “NEWTON & CO.'S TOURISTS’ a” & FIELD GLASSES. Tourist’s Telescope, with Caps and Strap, £2 ros. to £3 35. Race Giass, in Sling Case, £1 10s. Dirto, with changing Eye Lenses, £3 10s. to £5. Opera GiasseEs, in Case, from 155. AtuMiInium TELESCOPE, Portable, with Caps and Strap, from £4 4s. ALUMINIUM FieLD or Race Gtiass, in Case, with Strap, from 43 ros. A.tumiNniuM Ditto, with 3 Sets of Eye Lenses, in Case, from £5 5s. ALUMINIUM OPERA GLASSES, from £2 15s. NEWTON & CO. OPTICIANS TO THE QUEEN AND GOVERNMEN7, °3 FLEET STREET, LONDON. A NEW GAS FURNACE (Holloway’s Patent) FOR CHEMISTS AND ASSAYERS. POPULAR PRICES. C GATALOCUE BACKGROUNDS ON APPLICATION. JAMES sriath SONS & CO., LtD., VICTORIA BRIDGE, MANCHESTER. THE = _ ANEROO. oii ote -COOK’S. .) | For Measuring Altitudes ‘without Calculation. (New ItiustraTED Price List FreE By Post.) Made only by NEGRETTI & ZAMBRA, LESS CRACKING. PARTS SEPARATE. a) Se _ All particulars from SOLE MAKERS: JOHN J. GRIFFIN & SONS, LoD. 20-26 SARDINIA STREET, LONDON, W.C. SCIENTIFIC INSTRUMENT MAKERS to THE QUEEN, 38 HOLBORN VIADUCT, E.C. BRANCHES : 46 CORNHILL; 122 REGENT STREET. Ixul UNIVERSITY OF GLASGOW. ASSISTANT EXAMINER. The University Court of the University of Glasgow will shortly proceed ‘to appoint an EXAMINER for DEGREES in MEDICINE, with special -qualifications to Examine in Zoology. ane appointment will be from date of appointment till 31st December, 190. "The Annual Salary attached to the Examinership is £30. Candidates should lodge twenty copies of their application and testi- monials with the undersigned on or before 8th July next. ALAN E. CLAPPERTON, Secretary of the Court. gt West Regent Street, Glasgow. VICTORIA UNIVERSITY. UNIVERSITY COLLEGE, LIVERPOOL. ASSISTANT LECTURER IN MATHEMATICS, An ASSISTANT LECTURER will be appointed in July to assist the Professor of Mathematics. The Assistant Lecturer will be subject to the provisions of the Charter and Statutes of the College, and his duties will include :— (x) Lecture and class work in the day, averaging ten or twelve hours per week. (2) Lecture work in the evening of one or two hours per week. The appointment will be for three years, terminable at any date by three months’ notice, and may be extended by the Senate to not more than five years. Fe A The Salary is £150 per annum, together with a share of the fees of the evening classes. Applications, with testimonials, should be sent as soon as possible to the REGISTRAR, University College, Victoria University, Liverpool. June 1899. ST. BARTHOLOMEW’S MEDICAL SCHOOL. The Post of ASSISTANT DEMONSTRATOR of CHEMISTRY will be vacant at the end of the Summer Session. Full particulars can be obtained from the undersigned, to whom all applications must be forwarded on or before Saturday, 8th July. JAMES CALVERT, M.D., Warden. CITY OF BIRMINGHAM. MUNICIPAL TECHNICAL SCHOOL. The Corporation require the Services, in September next, of a LEC- TURER and DEMONSTRATOR in ELECTRICAL ENGINEER: ENGand ALLIED SUBJECTS. Salary, 4125 per annum. Full particulars and form of application will be forwarded on receipt of a stamped addressed foolscap envelope. GEO. MELLOR, Secretary. Offices of the School, Suffolk Street, 7th June, 1899. DEWSBURY AND DISTRICT TECHNICAL SCHOOL. WANTED, an ASSISTANT SCIENCE MASTER (Chemistry; Physics, and Physiography) for Session 1899-1900, five evenings per week. Must have had experience in teaching Practical Physics. Apply, stating Salary required, not later than sth July, to P. F. LEE, Secretary. LONDON MATRICULATION AND HOSPITAL SCHOLARSHIPS. QUERNMORE. Special Preparation for the above, Privately, in Class, or by Corre- spondence, by Messrs. JOHN GIBSON (First Class, Cambridge) and G. ‘LOLY (First Class, London), with large Staff of Specialist Tutors, Resident Pupils received at Upper Norwood. Long list of successes on application. N.B.—The London Matriculation Gude, with Examination Papers and Solutions (price rs.), isissued each January and June. Address: Messrs. GIBSON & LOLY, 24 Chancery Lane, W.C. NWALORE [JUNE 22, 1899 HANDSWORTH TECHNICAL SCHOOL (STAFFS.). WANTED an ASSISTANT MASTER, Mechanical Engineering’ Subjects. Must be capable of taking Practical Mechanics, and to assist } in Elementary Physics. Teaching experience very desirable. Com- mencing Salary, £100. Apply, with copies of testimonials, not later than | July 4th, to W. J. HARRIS (Hon, Sec.). TECHNICAL COLLEGE, HUDDERS- FIELD.—Principal, S. G. Rawson, D.Sc. The ASSISTANT LECTURESHIPin ENGINEERING is Vacant. Salary, £120 per annum. Further information and Statement of Duties may be obtained upon application. T. THORPE, Secretary. BRADFORD GRAMMAR SCHOOL.— ASSISTANT MASTERSHIP. A Graduate in Honours is required in September for Chemistry and Physics in Schoolof Science. Salary 4200, non-resident. Apply at once to HEap MASTER. Now Ready. No. 13. Price 1s. THE SCIENTIFIC ROLL. Climate: Baric Condition, To be completed in Sixteen Numbers. Conducted by ALEXANDER RAMSAY. Prospectuses and Subscription Forms Free by Post on application to the Publishers. A few of Nos. x to 12 still in print, price 1s. each. THE GEOLOGICAL TIME PAPERS AND CHARTS. No. 1. The ‘‘R” Geological Time Scale, price 1¢@. Nos. 0 to 3 Charts, 3d. each. Post free rd. extra. Now ready. London: O'DRISCOLL, LENNOX, & CO., Printers and Publishers,” ro & r2 Elephant Road, Elephant and Castle. THE ELECTRICAL GENERAL ENGINEERING COLLEGE, AND EXPERIMENTAL ENGINEERING WORKS, 2 and 4 PENYWERN ROAD, EARL’S COURT, LONDON, S.W., Trains Students for Electrical, Mechanical and Mining Engineering. Develops Electrical and Mechanical Patents. Constructs Experimental and Special Machinery and Models to Specification. TUITION.—ALL EXAMINATIONS —MEDICAL AND SCIENTIFIC. Well-fitted Laboratories.— “*R.C.,” 9 Heathcote Street, Mecklenburgh Square. THE MAINTENANCE OF SOLAR ENERGY ; or, Preliminary Notes on the Evolution and Devolution of the Solar System. By F.R.A.S. Price 3s. net. THE SOUTHERN PUBLISHING COMPANY, Lrp., 130 North Street, Brighton; and 62 Fleet Street, London, E.C. «Sale by Auction. STEVENS’ NEXT CURIO SALE, On TUESDAY, JULY 4th, will contain An extraordinary MUSICAL INSTRUMENT made out of a Human Skull from Paraguay, several splendid Bronzes from Benin, Nelson Relics, King George the Third’s Dressing Gown, War Trophies from Omdurman, a shrunk ucts Head from Ecuador, War Medals, Lord Cardigan’s Sword worn by him at Balaclava, &c.—38 King Street, Covent Garden. NOTICE. — Advertisements and business letters for NATURE should be addressed to the Publishers Baronial communications to the Editor. SUBSCRIPTIONS TO ‘*NATURE.”’ 4 s. a. VWearlys.f ic) en oaten tcl so/mteh cure seis saiopt eR Halfsyearlysy aces) owes) Ol ao eacino ce LEO Quarterly . . foie ean OY O To ALL PLACES ABROAD :— Yearly citety sivoh city ise ue foe oie eT OBA Half-yearlys §/c ecm) secs < AVN ise 5 6 Quarterly c= sn. eee fo) fe) The telegraphic address of NATURE zs “PHUSIS,” LONDON. CHARGES FOR ADVERTISEMENTS. PENIS CH *Three LinesinijGolumnmyey = .. . \. seen OnNZanO Per Line after . . « 0.1059 One Eighth Page, or ‘Quarter Column | 0 18 6 Quarter Page, or Half aColumn ... 115 oO Half a Page, oraiGolumny. . ... 2093) 5 0 Whole Page .. . 5a 8 6 60 * The first line being in heavy type is chaegedl for as Two Lines. Cheques ane Money ii aa payable to MACMILLAN & CO., Limited. OFFICE: ST. MARTIN’S STREET, LONDON, W.C. SSS A WEEKLY. [LLUSYPRAT =D JOURNAL OF SCIENCE. “To the solid ground Of Nature trusts the mind which butlds for aye.” —WORDSWORTH. No. 1548, VOL. 60] THURSDAY, JUNE 29, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] NEWTON & CO.’S CHEAP TELESCOPE. Look-out Telescope, having a 3-in. Object-Glass, Body Tube of Brass, 34 feet long, fitted with Rack and Sliding Tubes for Adjustment, mounted Altazimuth with Metal Cradle and Bearings on Mahogany Stand, 5 feet high. The Terrestrial fye-piece will show a church clock at 10 miles distance, and the Astronomical Eye-piece the Moon, Jupiter, Saturn, and divide many of the Double Stars. £7 10s. CATALOGUE OF TELESCOPES ON APPLICATION. NEWTON & CO. OPTICIANS TO THE QUEEN AND GOVERNMENT, 3 FLEET STREET, LONDON. BEC F’S NEW Z MICROSCOPE THE “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Eye-piece; Double Nose- piece, Two Object-glasses, 2/8” and 1/6’, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 R. & J. BECK, Ltd., 68 CORNHILL, LONDON, E.C. [All Rights are Reserved: BROWNING'S PLATYSCOPIC LENS. With Larger Angles, Increased Field, and Improved Definition Engraved Real Size. AN ACHROMATIC COMBINATION, COMBINING THE DEFINITION OF A MICROSCOPE WITH THE PORTABILITY OF A POCKET LENS, “Tf you carry a small Platyscopic Pocket Lens (which every observer of Nature ought to do).""—GranT ALLEN in Knowledge. The Platyscopic Lens is invaluable to botanists, mineralogists, or ento- mologists, as it focuses about three times as far from the object as the | Coddington Lenses. This allows opaque objects to be examined easily. The Platyscopic Lens is made of four degrees of power, magnifying respectively 10, 15, 20, and 30 diams. ; the lowest power, having the largest field, is the best adapted for general use. The Lenses are set in Ebonite Cells, and mounted in Tortoiseshell Frames. Price of the Platyscopic Lens, mounted in Tortoiseshell, magnifying either 10, 15, 20, 07 30 diameters, each power, 15s. r In nickelised German Silver, each power, 17s. 6d. Illustrated Description sent free. | JOHN BROWNING, 63 STRAND, LONDON, W.C. NEGRETTI & ZAMBRAS IMPROVED SELF-RECORDING RAIN GAUGE. DESCRIPTIVE PRICE LIST POST FREE. INVENTED AND MADE ONLY BY NEGRETTI & ZAMBRA, Scientific Instrument Makers to Her Majesty the Queen, 38 HOLBORN VIADUCT, E.C. Branches— 45 CORNHILL, E.C., and 122 REGENT STREET, W. Ixx ENGINEERING AND CHEMISTRY. CITY AND GUILDS OF LONDON INSTITUTE. SESSION 1899-1900. The Courses of Instruction at the Institute's CentTrat TECHNICAL ‘CoLieGE (Exhibition Road) are for Students not under 16 years of age ; those at the Institute’s TECHNICAL COLLEGE, Finspury, for Students motunder 14 years of age. The Entrance Examinations to both Colleges are held in September, and the Sessions commence in October. Particulars of the Entrance Examinations, Scholarships, Fees, and Courses of Study, may be obtained from the respective Colleges, or from the Head Office of the Institute, Gresham College, Basinghall Street, E.C. CITY AND GUILDS CENTRAL TECHNICAL COLLEGE. (EXHIBITION Roap, S.W.) A College for higher Technical Instruction for Students not under 16 pre- @aring to become Civil, Mechanical, or Electrical Engineers, Chemical and other Manufacturers, and Teachers. Fees for a full Associateship Course, 425 per Session. Professors :— Civil and Mechanical Engineering W.C. Unwin, F.R.S., M.Inst.C.E. ie E. Ayrton, F.R.S., Past Pres. Inst. E.E. jH. E. ArmstTRONG, Ph.D., LL.D., +. 4 F.R.S., Dean of the College for the \ ‘Session. O. Henricr, Ph.D., LL.D., F.R.S. Electrical Engineering ‘Chemistry Mechanics and Mathematics CITY AND GUILDS TECHNICAL COLLEGE, FINSBURY. (LeonarpD STREET, City Roan, E.C.) Provides Courses of Intermediate Instruction for Day Students not. under £4 years of age, preparing to enter Engineering and Chemical Industries. ®ees, £15 per Session. Professors :— S. P. THompson, D.Sc., F.R.S. (Principal of the College.) Engineering and\ we Datpy, M.A., B.Sc., M.I.M.E. R. Mecpora, F.R.S., F.1.C. JOHN WATNEY, Hon. Secretary. City and Guilds of London Institute, Gresham College, Basinghall Street, E.C. Physics and Electrical Engineering { Mechanical Mathematics Chemistry as aed an oo 4 VICTORIA UNIVERSITY. UNIVERSITY COLLEGE, LIVERPOOL. ASSISTANT LECTURER IN MATHEMATICS. An ASSISTANT LECTURER will be appointed in July to assist the Professor of Mathematics. The Assistant Lecturer will be subject to the provisions of the Charter and Statutes of the College, and his duties will include :— (x) Lecture and class work in the day, averaging ten or twelve hours per week. (2) Lecture work in the evening of one or two hours per week. The appointment will be for three years, terminable at any date by three ‘months’ notice, and may be extended by the Senate to not more than five "years. The Salary is £150 per annum, together with a share of the fees of the evening classes. Applications, with testimonials, should be sent as soon as possible to the REGISTRAR, University College, Victoria University, Liverpool. June 1899. UNIVERSITY OF ST. ANDREWS. The University Court of the University of St. Andrews will, at a meet- ing to be held in the month of July, appoint an ADDITIONAL EX- AMINER for Graduation in the subject of BOTANY. Applications, with testimonials, should be lodged on or before Saturday, 15th July, r899, with the undersigned, from whom further information may be obtained. JNO. E. WILLIAMS, Secretary and Registrar. St. Andrews, June 1899. ST. BARTHOLOMEW’S MEDICAL SCHOOL. The Post of ASSISTANT DEMONSTRATOR of CHEMISTRY will be vacant at the end of the Summer Session. Full particulars can be obtained from the undersigned, to whom all applications must be forwarded on or before Saturday, 8th July. JAMES CALVERT, M.D., Warden. SCIENCE MASTER Wanted in September for a First Grade School. Candidates should be Graduates of either Oxford, Cambridge, or London, with previous experience of Tuition. Subjects required, Chemistry and Physics. Salary up to £200 per annum. Apply personally, or by letter, to Messrs. GABBITAS, THRING, & Co., 36 Sackville Street, London, W. NATURE [JUNE 29, 1899 . BIRKBECK INSTITUTION, Breams Buildings, Chancery Lane, E.C. DAY AND EVENING CLASSES.| UNIVERSITY OF LONDON.—Complete Day Courses for all the Examinations in Science, and Complete Evening Courses for all the Examinations for the Science, Arts, and Law Degrees. SCIENCE CLASSES in every Branch, with Practical Work. Well- equipped Laboratories for Chemistry, Physics, Biology, Botany and Metallurgy. LECTURES on Political Economy, Commercial Geography, Common Law, Bankruptcy, Equity and Conveyancing, Logic, Psychology, and Ethics. CLASSES in Languages, Literature, English and Commercial Subjects. CONJOINT BOARD : Lectures and Practical Work in Chemistry, Physics, Biology, and Practical Pharmacy. Prospectus, Calendar (6d.), and Syllabuses of Classes on application to the Secretary. BRUNTS’ TECHNICAL SCHOOL, MANSFIELD. A SCIENCE MASTER required in the above School of Science after the Midsummer Holidays, Experience in teaching Practical and Theo- retical Physics and Chemistry essential. Salary, £110 per annum. Apply, stating age, qualification and experience, with copies of recent testi- monials, to C. E. STACEY, B.A., B.Sc. Lond., Head Master. ST. THOMAS’S HOSPITAL MEDICAL SCHOOL. The Vacancy in the Post of LECTURER on PHYSIOLOGY will be filled up in July. Duties to commence on October 3rd, 1899. Applications, with testimonials (copies), should be sent in not later than July rth. Particulars may be obtained from the undersigned. H. P. HAWKINS, Dean. Albert Embankment, London, S.E. MATHEMATICS. Temporary DEMONSTRATOR in MATHEMATICS wanted at once. Apply to the SUPERINTENDENT of the Heathcote Science Laboratories, Heathcote Street, Gray’s Inn Road. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. y;immersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Constant Currents. —T.," 9 Heathcote Street, Gray’s Inn Road. TUITION.—ALL EXAMINATIONS —MEDICAL AND _ SCIENTIFIC. Well-fitted Laboratories.— “"R.C.," 9 Heathcote Street, Mecklenburgh Square. SWINDON AND NORTH WILTS TECHNICAL SCHOOL. PRINCIPAL—F. W. SHURLOCK, B.A. (Lond.), B.Sc. The Committee invite Applications for the appointment of LECTURER in ENGINEERING SUBJECTS. Commencing Salary, £150 per annum. To conduct Evening Classes during the months from September to May in Engineering Subjects and the Sciences connected therewith, and to assist in the Day Technical School. Practical workshop experience essential. Forms of application, which must be returned not later than July 6, may be obtained from the S—crETARY, Technical School, Swindon. June 16, 1899. UNIVERSITY COLLEGE, LONDON. JODRELL PROFESSORSHIP OF PHYSIOLOGY. This Chair will shortly be Vacant by the resignation of Prof. E. A. Schafer. Applications, accompanied by such testimonials and references as Candi- dates may wish to submit, should reach the SecreTARY by Monday, July 17th, 1899. Further information will be sent on application to the SECRETARY. The new Professor will enter on his duties next October. J. M. HORSBURGH, M.A.,, Secretary. / \S A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. “To the solid ground Of Nature trusts the mind which builds Jor aye.’ —WORDSWORTH. No. 1549, VOL. 60] THURSDAY, JULY 6, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] ee Rights are Reserved. NEWTON & CO.’S | [ Victoria’ Hote Guta HEAP TELESCOPE. From £1 1s to £10 10s. HIGH Look-out Telescope, having a 3-in. Object-Glass, Body | ube of Brass, 34 feet long, fitted with Rack and Sliding | ubes for Adjustment, mounted Altazimuth with Metal Cradle ad Bearings on Mahogany Stand, 5 feet high. The Terrestrial tye-piece will show a church clock at ro miles distance, and | 4e Astronomical Eye-piece the Moon, Jupiter, Saturn, and | ivide many of the Double Stars. £7 10s. CATALOGUE OF TELESCOPES ON APPLICATION. CATALOGUE ___ NEWTON Vi ce: 8 pS | : es CAE 3 ove awo coveesrex” | VAMES WOOLLEY, SONS & 6O.. LTO, 3 FLEET STREET, LONDON. VICTORIA BRIDGE, MANCHESTER. A NEW DEPARTURE in CHEMICAL BALANCES. NEGRETTI & ZAMBRA’S BALANCE on Poisiec BINOCULARS AND TELESCOPES. POPULAR PRICES. Mahogany Base, Three Makers of the ‘OFFICER OF THE WATCH” TELESCO egies Makers ; oR OF a Wé UESCOPE, Levelling Screws, &c., in use on all the vessels of H.M. Navy. Plummet for levelling. Adjusting Screws for counterpoising Be Steel Knife Edges. Will carry 100 grms. i each pan and turn with 1-2m.g. 24/- —Fr =: bea) Nickel-plated, covered with Brown Leather. PRITIGH qos cst pre aehOS. BeRnece.D DERN ITION & Hig H POWE 2} 12 p Se 2-2, | - i “ Ls i Pe As supplied by NEGREDM| & ZAMBRA to ulate War Office. Length, when closed, 11 inche Combining high px and portability. BALANCE as above, with Agate Badges bound in Brass. Will carry 100 NEGRET TEP Rg 2 AMBRA, Eros, andeuemWwith 0-5 29/6 SCIENTIFIC INSTRUMENT MAKERS to the QUEEN, eae ed = HOLBORN VIADUCT, E.C. JOHN J. GRIFFIN & so NS, Lo, see 45 Senn p 122 Cee ie STREET. 20-26 SARDINIA STREET, LONDON, W.C. IvLusTRATED Price Lists FREE BY Post. Ixxvill mea TURE " (Jury 6, 18 : FIRST ANNOUNCEMENT TO READERS OF “NATURE.” HE proprietors of Tue Times have, within recent years, greatly ex- tended the scope of that newspaper's operations. The impression of Tue Times which appears at four o'clock in the morning is now followed not only by a second edition, published at half-past one in the afternoon, chiefly for circulation in the City; by THe Mart, published three times a week, and by THe Times Week Ly Epition; but also by LIrERATURE, a critical review which appears every Saturday. The publication of occasional biographies, annual summaries, and other monographs, reprinted from the columns of THe Times, has been followed by the publication of a series of periodical law reports and digests of cases, as well as by the half-yearly ‘‘ Issues,” an acconnt of newly-organised public companies. Four years ago THE Times Atlas was published, to which THE Times GAZETTEER has recently been added. Andin March, 1898, Tue Times Reprint of the Encyclopedia Britannica (oth edition) was offered to the public. In the course of only one year, more than 18,000 copies—450,000 volumes—of this standard work have been sold by Tue Times. A NEW WORK OF REFERENCE. The undertakings of Tue Times are now further extended by the issue of Tue Century Dictionary, a word-book and fact-book combined, at once the most complete lexicon of the English language and the most convenient encyclopedic work of reference for the purpose of quickly arriving at isolated facts, Peculiarly useful as a dictionary to the possessors of the Encyclopedia Britannica (which indeed contains not less than 10,000 words which no pre- vious dictionary had defined) THe Century Dictionary is alsoa most con- venient adjunct to the Encyclopzedia Britannica from another point of view. The exhaustive treatises in the Encyclopedia Britannica discuss groups of facts. They are the best monographs in the language, and the reader who has an hour's time to spend will always find in the Encyclopedia Britannica a clear and agreeably written account of any branch of art, science, or history which he desires to investigate. FOR BUSY MEN AND WOMEN. Tue Century Dicrionary, on the other hand, divides the vast structure of knowledge in greater number of compartments, enabling the reader to find, with the least loss of time, any one item of information at which he may desire toarrive; to examine, so to speak, the contents of any one pigeon- hole without handling the papers in any other pigeon-hole. The Ency- clopedia Britannica invites the reader to contemplate broad gardens of knowledge, while WHE Century Dscrionary presents to his hand which- ever one of the individual flowers he happens at the moment to want. Such is the relation between the two books, if Tue CenTurY DICTIONARY be regarded as a fact-book. As a word-book, it is incomparably the best dictionary in existence. The New English Dictionary will no doubt be of very great value, and especially to philologists, when it is completed, ten years hence ; but, meantime, THE Cenrury Dictionary is the largest as well as the most comprehensive and beautifully illustrated lexicon of the English language. It completes, in the most admirable fashion, THE Times Library of Reference, and it will no doubt find its way to the shelves of every well-chosen library, however modest NOW, RATHER THAN LATER. There is, however, in this connection, a very relevant question, as to the desirability of procuring the work as soon as possible. Book-buyers have learned by experience, that most books are at first offered in an expensive form, and later, ina cheaper guise, at reduced prices. ‘The novel published last year in three volumes, at a guinea and a half, may be had this year for six shilli the book of travel which cost fifteen or eighteen shillings a few months ago, isto be procured to-day, by those who waited patiently, for half the pric Tue Times has, however, in its issue of the Encyclopedia Britannic d of THe Century Dictionary, broken away from this tradi- tion. It offered the first few thousand copies of the Encyclopedia Britannica 1 hundred letters from purchasers of the Century DicTioNaRy. ~ Che Cimes THE CENT@RY DIGHIONARY A FACT-BOOK AND WORD-BOOK COMBINE A NEW WORK ON A NEW PLAN—GIVING, FOR THE FIRST TIME, EVERY FORM USAGE KNOWN, WHETHER ENGLISH, AMERICAN, AUSTRALIAN, PROVINCIAL OR COLLOQUIAL. Eight sumptuous volumes; '7,000 large quarto pages; 500,000 definitions; 7,500 illustrations; 300,000 quotati a work of which the editorial cost, alone, was more than £200,000: OF SPELLING, PRONUNCIATION, 1 | at 20 per cent. less than the price at which many thousands of copies ¥ subsequently sold. Those who promptly ordered their copies had the bes| of the minimum prices. They took the trouble to act assoon as the offer | made, and those who waited were compelled either to do without the or to pay more for it. THE SECRET OF THE BARGAIN. In the case of THE Cenrury Dicrionary, a limited edition was offere few weeks ago, for £13, in half Morocco binding, or thirteen monthly ments of one guinea each: little more than half the publishers’ price. price still obtains, and any reader who at once applies to THE Times fe copy of the work may benefit by this temporary arrangement. The best 1 to introduce a really good work of reference is to sell as quickly as possi without regard to immediate profits, a limited edition of it; for, if the b will speak for itself, every copy that finds its way to any house supplie| most eloquent and unanswerable advertisement. This is what is now bi done with THe Century Dictionary. But the price will be increase soon as the remaining copies of this first edition have been exhausted, ; there is now so little time to lose that those who intend to procure the w) at the present prices will do well to make immediate use of the order form A ROYAL ROAD, The old saying that there is no royal road to learning is a wholese) maxim for nursery use. The first marches upon that laboured route m- necessarily be difficult, for the power of rapid and accurate comprehens_ can only be acquired by vigorous preliminary discipline. The long way league upon league of cube root, irregular verbs, and the catalogue of ki and queens—hardens the muscles once for all, and those who shirk in 1 shady by-paths never acquire a sturdy gait. When, however, the end of {| broad high road is reached, the conditions of the journey are greatly alter¢| The professional man has his mountain to face: the distant summit to attained by the few, the hill pastures of moderate success by the many. F all the rest of us, further progress is not obligatory. If we read books wor reading, and read them intelligently, we get more out of life than if « confine our energies to the gaining or spending of money, but no very stro incentives impel us. ‘'GENERAL INFORMATION.” In the course of the more or less desultory progress toward the positi occupied by what one calls ‘well informed ’” men and women, we are all liberty to select our own itineraries. And good books of reference u questionably offer us a royal road to this supplementary sort of learnin Once at the end of the prescribed routé, there is no reason why we shou not stray at will, and be the better for our little excursions, if only we pau to examine what we see about us. It is this habit of observing, of questionin of verifying that we’ need to cultivate. But it is a habit which those wh have completed the tasks of routine education are not likely to acquir unless the way is made very smooth for them. NEW WORDS AND NEW FACTS. It is in this connection that Tur Century DicTioNaRY may be fairl considered to provide a royal road tolearning—to that sort of learning whic enables us to think intelligently and to talk intelligently about the currer topics of the day. ‘The occurrence in one’s newspaper of an unfamilic word, the mention of an unknown substance or an unknown proces: arouses in the average reader’s mind enough of curiosity to mak him turn to a work of reference, if he knows that the informatio he desires will easily be found. But such casual invitations to th pursuit of knowledge are hardly strenuous enough to draw him amon the bristling difficulties of special text-books. He will learn a little if he i not afraid of having to learn too much; he will spend five minutes ver: profitably, if he is not afraid that he will be led to make too good a use o half an hour. With all the good will in the world one cannot learn every thing there is to learn, and if, when we are confronted by any new fact, we learn only enough about it to understand a paragraph in a newspaper, or < page ina review, we are at any ratea little better off than if we had remainec WHAT SOME EARLY PURCHASERS SAY ABOUT THE “ CENTURY DICTIONARY.” THE NEW WORK ISSUED BY The Times, AR HERE have been published, in the columns of THE TIMES, since its issue of the Century DieTionary was first announced on May 8th, more than a It is impossible to reproduce them all in the limited space of this one advertise- in outer darkness. nt, but a few representative letters from different classes of subscribers will show how general is the usefulness of the work. 1ese letters are not empty compliments. worth. The point of view from which they hey are quite prepared to find fault if there is fault to be found. heir money than they had hoped to get. is these show, too, how the id magazines are, necessarily, the opinions of specialists. ed to the needs of the g ral reader. more for t Suc for new. directly Here we have the direct expression of the possessor's judgment upon the work—the opinion of the man who bought it to use, They are written by people who sent money to THE TIMEs, expecting to receive from THE TIMEs full regard the volumes of the Cenrury Dictionary There is none. is not an indulgent one. When they unpack the They see that they made a good bargain; that they got even public use the Century Dictionary, and what they find in it. The opinions of the critics who review books A work of reference may be of the utmost interest to them, and yet not be Iu < and finds it useful. Pe ERK TeetisiRaArED JOURNAL OF SCIENCE: “© To the solid ground Of Nature trusts the mind which builds for aye.” —WORDSWORTH. No. 1550, VOL. 60] THURSDAY, JULY 13, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] {All Rights are Reserved. EWTON & CO.’S GARDEN SUN-DIALS. = = SUN-DIALS. ON APPLICATION, From 4 in., 20s., to 18 in., £8 10s. BRASS CIRCULAR HORIZONTAL FULL AND DESCRIPTIVE PRICE LIS‘ —< A ATT I0, 15, 20 07 30 diameters, each power, Ss OPTICIANS TO THE QUEEN AND GOVERNMENT, In nickel German Siiver, each power, 17s. 6d. Illustrated Description sent free. ——— eee JOHN BROWNING, 63 STRAND. LONDON, W.C. Paks - NEGRETTI & ZAMBRA’S BEC K’S TRAVELLER'S SCIENTIFIC COMPANION. NEW 25 : — MICROSCOPE THE “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Eye-piece; Double Nose- piece, Two Object-glasses, 2/3” and 1/6’, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 gat OES ee ae =e a “NEGRETTI & ZAMBHA, B K | SCIENTIFIC INSTRUMENT MAKERS TO THE QUEEN R. SS J. EC o) Ltd., | 38 HOLBORN VIADUCT, E.C. 2 68 CORNHILL, LONDON, E.C, Brancnes—45 CORNHILL; 122 REGENT STREET. Consisting of Aneroid Barometer with Altitude Scale, Compass with Patent Dial ana Thermometer for Air Temperatures (or a Clinical Thermometer may be substituted), PRICE £4 10s. to £7 10s. Can also be had Mounted in Gold and Silver \{/ases. Useful Present for Gentlemen visiting the Colonies and Officers on Foreign Service. y* clxx BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, BURLINGTON HOUSE, LONDON, wW. DOVER MEETING, SEpremMBerR 13 TO 20, 1899. PRESIDENT-ELECT : SIR MICHAEL FOSTER, K.C.B., D.C.L., LL.D., Sec.R.S. The JouRNAL, Prestpent’s Appress, and other Printed Papers issued by the Association during the Annual Meeting will be forwarded daily by post to Members and others unable to attend, on application and prepay ment of 2s. 6¢. to the Clerk of the Association, Mr. H. C. STEWARDSON, Reception Room, The College, Dover, on or before the first day of the Meeting. G. GRIFFITH, Assistant General Secretary. ENGINEERING AND CHEMISTRY. CITY AND GUILDS OF LONDON INSTITUTE. SESSION 1899-1900. The Courses of Instruction at the Institute's CENTRAL TRCHNICAL Co.vecE (Exhibition Road) are for Students not under 16 years of age; those at the Institute's Tecunicat CoLveGe, Frnspury, for Students notunder 14 years ofage. The Entrance Examinations to both Colleges are held in September, and the Sessions commence in October. Particulars of the Entrance Examinations, Scholarships, Fees, and Courses of Study, may be obtained from the respective Colleges, or from the Head Office of the Institute, Gresham College, Basinghall Street, E.C. CITY AND GUILDS CENTRAL TECHNICAL COLLEGE. (Exuisition Roan, S.W.) A College for higher Technical Instruction for Students not under 16 pre- paring to become Civil, Mechanical, or Electrical Engineers, Chemical and other Manufacturers, and Teachers. Fees for a full Associateship Course, 425 per Session. Professors :— Civil and Mechanical Engineering W.C. Unwin, F.RS., M.Inst.C.E. Electrical Engineering * ee, oes ENETON, F.R.S., Past Pres. jH. E. ArmMstTrRoNG, Ph.D., LL.D., F.R.S., Dean of the College for the \ Session. O. Hewrict, Ph.D., LL.D., F.R.S. CITY AND GUILDS TECHNICAL COLLEGE, FINSBURY. (Leonarp Srreet, City Roap, E.C.) Chemistry Mechanics and Mathematics Provides Courses of Intermediate Instruction for Day Students not under 14 years of age, preparing to enter Engineering and Chemical Industries. Fees, £15 per Session. Professors :— S. P. Tuompson, D.Sc., F.R.S. Physics and Electrical Engineering \ (Principal of the College.) Mechanical Engineering and D , Gees ae ering @n' | W.E. Dacay, M.A., B.Sc., M-ILM.E. Chemistry R. Mevpora, F.R.S., F.1.C. JOHN WATNEY, Hon. Secretary. City and Guilds of London Institute, Gresham College, Basinghall Street, E.C. THE DAVY FARADAY RESEARCH LABORATORY OF THE ROYAL INSTITUTION. DIRECTORS: The Right Hon. LORD RAYLEIGH, M.A., D.C.L., LL.D., F.R.S. Professor DEWAR, M.A., LL.D., F.R.S. SUPERINTENDENT OF THE LABORATORY: Dr. ALEXANDER SCOTT, M.A., D.Sc., F.R.S! This Laboratory, founded by Dr. Ludwig Mond, F.R.S., as a Memorial of Davy and Faraday for the purpose of promoting original research in Pure and Physical Chemistry, will be open during the following Terms :-— Michaelmas Term.—Monday, October 2, to Saturday, December 16. Lent Term.—Monday, January 8, to Saturday, Apri! 7. Easter Term.— Monday, April 30, to Saturday, July 28. Under the Deed of Trust, workers in the Laboratory are entitled, free of charge, to Gas, Electricity and Water, as-far as available, and, at the discretion of the Directors, to the use of the apparatus belonging to the Laboratory, together with such materials and chemicals as may be authorisec, All persons desiring to be admitted as workers, must send evidence of Scientific training, qualification, and previous experience in original research, along with a statement of the nature of the investigation they propose tc undertake. Candidates must apply for admission during the course of the preceding Term. | Forms of Application can be had from the AssISTANT SECRETARY, Royal Institution, Albemarle Street, W, NATURE [SEPTEMBER 7, 1899 UNIVERSITY COLLEGE, LONDON. ENGINEERING AND ARCHITECTURAL DEPARTMENT. ASSISTED BY TECHNICAL EDUCATION BOARD OF LONDON COUNTY COUNCIL AND BY THE CARPENTERS’ COMPANY. SESSION 1899-1900. The COURSES of INSTRUCTION in Mechanical, Civil, Municipal, and Electrical Engineering and Architecture COMMENCE on OCTOBER 3. They are arranged to cover periods of two and three years. Particulars of the Courses, of Entrance Scholarships, of the Matriculation Examination, and of the Fees, may be obtained from the SECRETARY. : PROFESSORS. MECHANICAL ENGINEERING, T. Hupson Beare, M.I.C.E. ELECTRICAL ENGINEERING, J. A. FLEMING, F.R.S. MUNICIPAL ENGINEERING, Ospert Cuabwick, M.I.C.E., C.M.G. x CIVIL ENGINEERING, L. F. Vernon Harcourt, M.I.C.E. ARCHITECTURE, T. RocGer Smiru, F.R.1.B.A. PHYSICS, H. L. Catcenpar, F.R.S. CHEMISTRY, W. Ramsay, F.R.S. = APPLIED MATHEMATICS, K. Pearson, F.R.S. ECONOMIC GEOLOGY, T. G. Bonney, F.R.S. MATHEMATICS, M. J. M. Hitt, F.R.S. The new Wing of the College, opened by H.R.H. the Duke of Connaught in May 1893, contains spacious Mechanical and Electrical Engineering Laboratories, Workshops, Drawing-Office, Museum, and Lecture Theatres. The Laboratories are fitted with all the best appliances for Practical Work and for Research Work of the most advanced character. UNIVERSITY COLLEGE OF NORTH WALES (BANGOR). SESSION 1899-1900 will open on TUESDAY, OCTOBER 3. DEPARTMENTS of PHYSICS, CHEMISTRY, and BIOLOGY. f Prof. A. Grav, M.A., LL.D., F.R.S. \ BIO LCS eve svecse Assistant Lecturers and Demonstrators, T. C. Baivuig, M.A., B.Sc., and E. TayLor Jones, D.Sc. { Prof. J. J. Dosppiz, M.A., D.Sc. CHEMISTRY... | Assistant Lecturer and Demonstrator, F. MARSDEN, M.Sc., Ph.D. (Heidelberg). Botany—Prof. R. W. PHILLirs, ae D.Sc. J avy ce Assistant Lecturer - and emonstrator, J. BIOLOGY, (css. ; MGGUOENVILL AMS. Zoology—Prof. Puitip J. WHITE, M.B., F.R.S.E. The Classes and Laboratory Courses of this College are arranged to suit the requirements of Students of Practical Science, as well as of Students preparing for University and other Examinations. The Lectures in Chem- istry, Physics, Botany, and Zoology are recognised by the Universities of Edinburgh and Glasgow as qualifying for the Medical Degrees of those Universities. One Annus Medicus may be taken at this College. The extensive Laboratories (Physical, Chemical, and Biological) are fully equipped for Study and Research, and in the Physical Department special provision has been inade for the teaching of Electrical Engineering. A Special Course has been arranged in this subject. Inclusive Tuition Fee, £11 1s. LABORATORY FEES (per Term) on the scale of £1 rs. for six hours a week, in each Department. A considerable number of Scholarships and Exhibitions are open for com- petition at the beginning of each Session, and several are awarded at the close of each Session on the result of the year's work. For full information as to Science and Arts Courses, apply for Prospectus to the Secretary and Registrar, J. E. LLOYD, M.A. UNIVERSITY COLLEGE, LIVERPOOL (VICTORIA UNIVERSITY). SCIENTIFIC DEPARTMENTS. SESSION 1899-1900 will openon MONDAY, OCTOBER 2° PHYSICS ... ... ... .. Prof. OLivER LopceE, D.Sc., F.R.S. CHEMISTRY ... ... Prof. J. CAMeBELL Brown, D.Sc. ZOOMOGY wescosrvene Prof. W. A. HErRpMaNn, D.Sc., F.R.S. BOTANY ... ... ... 4. Prof. R. J. Harvey Gipson, M.A., F.L.S. PHYSIOLOGY ... :.. Prof. C. S. SHERRINGTON, M.A., M.D., F.R.S. In addition to Courses preparing for Victoria and London University Degrees, the Laboratories in the above Departments are open to Male and Female Students alike for Study and Research at scales of Fees which can be obtained on application. 2 5 4 For full information as to Courses in the Science, Arts, and Medical Departments, apply to the Registrar, E. LONDINI, D.C.L. BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. HYGIENE AND PUBLIC HEALTH. The Course of Scientific Instruction, Practical and Theoretical, will begin on Thursday, October 5th, and extend over Three Terms. Further information on application to the Principat at the College. A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. ‘© To the solid on Of Nature trusts the mind which butl >_ WORDSWORTH. 5 for aye. No. 1559, VOL. 60] THURSDAY, SEPTE MBER 14, 1899. PRICE SIXPENCE. pecetcret as a Newspaper at the General Post Office.] NIRELESS S$. TELEGRAPHY. 2 | “‘ THE APPS- NEWTON’ “ "INDUCTION COILS made entirely in the London Workshops of NEW TON & CoO., 3S FLEET STREET, E.C., are now used by all the principal experts in Wireless Telegraphy, as w as well as in Radiography. \ NEW DEPARTURE in CHEMICAL BALANCES. BALANCE on Polished Mahogany Base, Th z Levelling Screws, &c. v Plummet for levelling Adjusting Screws counterpoising E Steel Knife E | Will carry 100 grms. each pan and turn with 1-2m.g. 24/- ALANCE as above, with Agate Edges bound in Brass, Will carry 10 grms. and turn with o.5 m.g- 29/6 OHN J. GRIFFIN & SONS, 20-26 SARDINIA STREET, LONDON, W.C. LD., All Rights are Reserved. STROUD AND RENDALL’S UNIVERSAL SCIENCE LANTERN has been devised for the projection of experiments. A hinged mirror is so placed that by the movement of a stud it may be intro- ducéd and placed at an angle of 45 degrees with the parallel beam. The beam is thus sent upwards through a horizontal conver- gent lens, on which slides or apparatus can be placed. Above this is the objective mounted ona brass pillar and the ob jective intended to send the image in anapprox- imately horizontal direction to the screen. Slides can also be directly pro- jected. PRICE £9 O 0 COMPLETE. REYNOLDS & BRANSON, Ltd., NEGRETTI & ZAMBRA’S TRAVELLER'S SCIENTIFIC COMPANION. 14 Commercial Street Leeds. Consisting of Aneroid Barometer with Altitude Scale, Compass with Patent Dial and Thermometer for Air Temperatures (or a Clinical Thermometer may be substituted). PRICE £4 10s. to £7 10s. Can also be had Mounted in Gold and Silver Cases. 1 Present for Gentlemen visiting the Colonies and Ofiicers or Foreign Service. NEGRETTI & ZAMEB RA, SCIENTIFIC INSTRUMENT MAKERS TO THE ()UEEN, 38 HOLBORN VIADUCT, E.C. BRANCHES—45 CORNHILL; 122 REGENT STREET Usefu clxxxil THE MIDDLESEX HOSPITAL MEDICAL SCHOOL. The WINTER SESSION, 1899-1900, will commence on MONDAY, OCTOBER 2. Mr. Joun Murray, F.R.C.S., will deliver an Intro- ductory Address, after which the prizes gained during the previous year will be distributed. Two ENTRANCE SCHOLARSHIPS (value £100 and £60) will be open for competition on September 21 and 22. One Entrance Scholarship (value £60), open to Students of the University of Oxford and of the University of Cambridge, will be competed for on September 21 and 22. Notice in writing to be sent to the Dean on or before September 14. Besides Scholarships and Prizes, there are annually EIGHTEEN RESIDENT Hospital Appointments open to Students, without extra fee. The Composition Fee for general Students for the whole Medical Curriculum is 135 guineas. Special provision is made for Dental Students and for Candidates for the Preliminary Scientific (M.B.) Examination. Special terms are made in favour of University Students who have already commenced their medical studies, and of University of London Students who have passed the Preliminary Scientific Examination, The New School Buildings, which provide large and fully-equipped laboratories for Physiology, Pathology, and Bacteriology, as well as a new dissecting room and chemical department, are now in regular use. The Residential College adjoins the Hospital, and provides accommo- dation for thirty Students. Prospectuses and all particulars may be obtained from W. PASTEUR, M.D., Dean.” UNIVERSITY COLLEGE, LONDON. The Session of the Faculty of Medicine will commence on October 2. Introductory Lecture, at 4 p.m., by Dr. G. F. BLackeEr, Assistant Obstetric Physician to the Hospital. The Examinations for the Entrance Scholarships and Medical Exhibitions will commence on September 26, Scholarships, Exhibitions, and Prizes of the value of £800 are awarded annually. In University College Hospital about 3000 In-patients and 35,000 Out- patients are treated during the year. Thirty-six Appointments, eighteen being resident (as House Surgeon, House Physician, Obstetric Assistant, &c.), are filled up by competition during the year, and these, as well as all Clerkships and Dresserships, are open to Students of the Hospital without extra fee. Resident Officers receiye free board and lodging. Prospectuses, with full information as to Classes, Prizes, &c., may be obtained from University College, Gower Street, W.C. H. R. SPENCER, M.D., F.R.C.P., Dean, J. M. HORSBURGH, M.A., Secretary. ST, BARTHOLOMEW’S HOSPITAL AND COLLEGE. PRELIMINARY SCIENTIFIC CLASS. Systematic Courses of Lectures and Laboratory Work in the subjects of the Preliminary Scientific and Intermediate B.Sc. Examinations of the University of London will commence on October 2 and continue till July, 1900, Attendance on this Class counts as part of the Five Years’ Curriculum, Fee for the whole Course £21, or £18 18s, to Students of the Hospital or single Subjects may be taken. There is a Special Class for the January Examination, For further particulars apply to the WARDEN OF THE COLLEGE, St. Bartholomew's Hospital, London, E.C. A Handbook forwarded on application THE LONDON SCHOOL OF TROPICAL MEDICINE, CONNAUGHT ROAD, ALBERT DOCK, E. (IN CONNECTION WITH THE HospITALs OF THE SEAMEN ; HosPITAL SOCIETY.) UNDER THE AUSPICES OF HER MAJESTY’S GOVERNMENT. The WINTER SESSION will commence on Monday, 2nd October, when the new School will be formally open for Students. A Travelling Scholarship of £300 will be offered to Students of the School. The Laboratories, Museum, Library, &c., are open daily. Lectures on Tropical Medicine, Tropical Hygiene, and Surgery in the Tropics, are delivered during the Winter, Summer and Autumn Sessions. Clinical Instruction is given daily in the Wards of the Hospitals. Special arrangements for Board will be made for those who may desire to weside on the premises. MEDICINE IN CONNECTION WITH UNIVERSITY COLLEGE AND ROYAL SOUTHERN HOSPITAL. MAJOR ROSS, late I.M.S. For prospectus and all particulars, apply to A. H. MILNE, B.A., Hon. Sec. Chamber of Commerce Liverpool. Lecturer NATURE SEPTEMBER 14, 1899 UNIVERSEIDY (COLLEGE, LIVERPOOL. (VICTORIA UNIVERSITY.) DEPARTMENT OF ENGINEERING. Session 1899-1900 commences October 2. Complete Courses of Instructio are arranged in (1) CiviL ENGINEERING, (2) MecHaNnIcAL ENGINEERING, (3) ELEcTRICAL ENGINEERING. These Courses enable Students to qualify for University Degrees, and fo the College Certificates in Engineering. They comprise, in addition t) special Engineering Lectures and Laboratory Work, Instruction in Mathe) matics, Physics, Electrotechnics, and Chemistry. Harrison Professor of Engineering (#45, CR -LL.D., F-R.S. Lyon Jones Professor of Experi- fOtiver J. Lopcr, D.Se., F.R.S. mental Physics... ace peas. eRe aA - ay * JF. S. Carey, M.A., late Fellow o Professor of Mathematics .., “-\. Trinity College, Cambridge. Grant Chair of Chemistry ... +. J. CamMpBELt Brown, D.Sc., F.1.C. The special Engineering Prospectus can be obtained on application to th REGISTRAR. =i UNIVERSITY OF GLASGOW. COURSES IN ENGINEERING SCIENCE. The Session opens on October 19. EnGINEERING—Prof. ARCHIBALD BARR, D.Sc., M.Inst.C.E. Nava. ARCHITECTURE AND MARINE ENGINEERING—Prof, J. HARVARD BILES, M.I.N.A. ELEcTRICAL ENGINEERING—Mr. JOHN D. CORMACK, B.Sc.,M.1.E.E Cuemistry—Prof. JOHN FERGUSON, M.A., LL.D. Natrurat PuitosopHy—(New Professor to be appointed before openin;: of Session.) Matuematics—Prof. WILLIAM JACK, LL.D. / Geo.ocy—Prof, JOHN YOUNG, M.D. Prospectuses of the Courses, with regulations for the Degrees of B.Se. anc D.Sc. in Engineering Science, and a List of Bursaries and Scholarship npen to Science Students, can be had from the Assistant CLERK. KING’S COLLEGE, LONDON. STUDENTS in ARTS and SCIENCE, ENGINEERING, ARCHI TECTURE, and APPLIED SCIENCES, MEDICINE, and _ othe branches of Education will be ADMITTED for the NEXT TERM Tuesday, October 3. Evening Classes commence Thursday, October 5. Students are classed on entrance according to their proficiency, and ter minal reports of the progress and conduct of Matriculated Students are sen to their parents and guardians. ‘There are Entrance Scholarships anc Exhibitions. Students may join either for the full Courses at a composition fee, or be admitted for the separate Classes. There are a few vacancies for Resident Students. For Prospectus and all information apply to the SECRETARY, King’ College, London, W.C. UNIVERSITY COLLEGE OF NORTH WALES, BANGOR. ELECTRICAL ENGINEERING. Professor ANDREW GRAY, LL.D., F.R.S., will begin, in OCTOBE! next, a Systematic COURSE of INSTRUCTION in Electrical Measure ment and Practical Electricity. The Physical Laboratory is fully equippec with a Compound Steam Engine, Dynamos, Transformer, Secondar: Battery, and the most approved modern Measuring Instruments for al Branches of Electrical Engineering. Laboratory Fees at the rate of £115 per Term for six hours per week. Composition Fee for all College Lecture for the Session, £10. Applications for Calendar, Prospectus, and general information to b: made to J. E. LLOYD, M.A., Secretary and Registrar. VICTORIA UNIVERSITY. THE YORKSHIRE COLLEGE, LEEDS. The 26th Session of the Department of Science, Technology, and Art: will begin on October 3, and the 69th Session of the School of Medicine or October 2, 1899. The Classes prepare for the following Professions: Chemistry, Civil Mechanical, Electrical, and Sanitary Engineering, Mining, Textile In dustries, Dyeing Art, Leather Manufacture, Agriculture, School Teaching aw, Medicine, and Surgery. , University Degrees are also conferred in the Faculties‘of Arts, Science Law, Medicine, and Surgery. Lyddon Hall has been established for Students’ residence. Prospectus of any of the above may be had from the REGISTRAR. SHEFFIELD. SESSION 1899-1900. The Departments commence as follows :— TECHNOLOGY SEPTEMBER 4. MEDICINE a in OCTOBER 2. ARTS AND SCIENCE OCTOBER 4. Prospectuses are now ready, and may be had on application. The College is open from ro to 2 during the Vacation. 4 A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. “To the solid ground Of Nature trusts the mind which budlds for aye.’—WORDSWORTH. No. 1560, VOL. 60] THURSDAY, SEPTEMBER 21, 1899. [PRICE SIXPENCE Registered as a Newspaper at the General Post Office.] WIRELESS TELECRAPHY. “ THE APPS-NEWTON” INDUCTION COILS made entirely in the London Workshops of NEW TON & CoO., 3S FLEET STREET, E.C., are now used by all the principal experts in Wireless Telegraphy, as well as in Radiography. BEC KH’sS NEW MICROSCOPE THE “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Hye-piece; Double Nose- piece, Two Object-glasses, 2/3” and 1/6”, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 No. 55. R. & J. BECK, Ltd., 68 CORNHILL, LONDON. E.C, | With Larger Angles, Increased Field, and Improved Definition | Engraved Real Size. | AN ACHROMATIC COMBINATION, | COMBINING THE DEFINITION OF A MICROSCOPE WITH THE | PORTABILITY OF A POCKET LENS. | _ ‘If you carry a small Platyscopic Pocket Lens (which every observer of | Nature ought to do)."—GraANT ALLEN in Knowledge. ; The Platyscopic Lens is invaluable to botanists, mineralogists, or ento | mologists, as it focuses about three times as far from the object as the Coddington Lenses. This allows opaque objects to be examined easily. The Platyscopic Lens is made of four degrees of power, magnifying respectively 10, 15, 20, and 30 diams. ; the lowest power, having the largest field, is the best adapted for general use. The Lenses are set in Ebonite Cells, and mounted in Tortoiseshell Frames. Price of the Platyscopic Lens, mounted in To rtotseshell, magnifying either 10, 15, 20, 0” 30 diameters, each power, 15s. In nichelised German Silver, each power, 178. 6d. Illustrated Description sent free. JOHN BROWNING, 63 STRAND, LONDON, W.C. NEGRETTI & ZAMBRA’S TRAVELLER'S? SCIENTIFIC ‘COMPANION. Consisting of Aneroid Barometer with Altitude Scale, Compass with Patent Dial and Thermometer for Air Temperatures (or a Clinical Thermometer may be substituted). PRICE £4 10s. to. £7 10s. Can also be had Mounted in Gold and Silver Cases Useful Present for Gentlemen visiting the Colonies and Officers on Foreign Service. NEGRETTI & ZAMERA, ScIENTIFIC INSTRUMENT MAKERS TO THR QUEEN, 38 HOLBORN VIADUCT, E.C. Brancues—4s5 CORNHILL; 122 REGENT STREET CXCIV NATURE (SEPTEMBER 21, 1899 THE DAVY FARADAY RESEARCH LABORATORY OF THE ROYAL INSTITUTION. DIRECTORS: The Right Hon. LORD RAYLEIGH, M.A., D.C.L. De) Hekas. Professor DEWAR, M.A., LL.D., F.R.S. SUPERINTENDENT OF THE LABORATORY: Dr. ALEXANDER SCOTT, M.A., D.Sc., F.R.S. This Laboratory, founded by Dr. Ludwig Mond, F.R.S., as a Memorial of Davy and Faraday for the purpose of promoting original research in Pure and Physical Chemistry, will be open during the following Terms :— Michaelmas Term.—Monday, October 2, to Saturday, December 16. Lent Term.—Monday, January 8, to Saturday, April 7. Easter Term.— Monday, April 30, to Saturday, July 28. Under the Deed of Trust, workers in the Laboratory are entitled, free of charge, to Gas, Electricity and Water, as far as available, and, at the discretion of the Directors, to the use of the apparatus belonging to the Laboratory, together with such materials and chemicals as may be authorisea. All persons desiring to be admitted as workers, must send evidence of scientific training, qualification, and previous experience in original research, along with a statement of the nature of the investigation they propose to undertake. qpesnaidates must apply for admission during the course of the preceding erm. Forms of Application can be had from the AssisTaNT SECRETARY, Roval Institution, Albemarle Street, W. UNIVERSITY COLLEGE, LONDON. ENGINEERING AND ARCHITECTURAL DEPARTMENT. ASSISTED BY TECHNICAL EDUCATION BOARD OF LONDON COUNTY COUNCIL AND BY THE CARPENTERS’ COMPANY. SESSION 1899-1900. The COURSES of INSTRUCTION in Mechanical, Civil, Municipal, and Electrical Engineering and Architecture COMMENCE on OCTOBER 3. They are arranged to cover periods of two and three years. Particulars of the Courses, of Entrance Scholarships, of the Matriculation Examination, and of the Fees, may be obtained from the SECRETARY. PROFESSORS. MECHANICAL ENGINEERING, T. Hupson Beare, M.I.C.E. ELECTRICAL ENGINEERING, J. A. FLemine, F.R.S. MUNICIPAL ENGINEERING, Ossert Cuapwick, M.I.C.E., C.M.G. CIVIL ENGINEERING, L. F. Vernon Harcourt, M.I.C.E. ARCHITECTURE, T. Rocer Smiru, F.R.I.B.A. PHYSICS, H. L, CaLLtenpar, F.R.S. CHEMISTRY, W. Ramsay, F.R.S. APPLIED MATHEMATICS, K. Pearson, F.R.S. ECONOMIC GEOLOGY, T. G. Bonney, F.R.S. MATHEMATICS, M. J. M. Hirt, F.R.S. The new Wing of the College, opened by H.R.H. the Duke of Connaught in May 1893, contains spacious Mechanical and Electrical Hngineering Laboratories, Workshops, Drawing-Office, Museum, and Lecture Theatres. The Laboratories are fitted with all the best appliances for Practical Work and for Research Work of the most advanced character. UNIVERSITY COLLEGE, LONDON. The Session of the Faculties of Arts and Laws and of Science will begin on Tuesday, October 3rd. The Prospectuses of the following departments are now ready, and may be had on application to the SECRETARY :— FACULTY OF ARTS. FACULTY OF LAWS. FACULTY OF SCIENCE. THE INDIAN SCHOOL. THE DEPARTMENT OF FINE ART. THE ENGINEERING DEPARTMENT. THE DEPARTMENT OF ARCHITECTURE. Students of both sexes are admitted to Classes without previous examin- ation, provided there is room. Scholarships of the value of £2000 are offered for competition annually. J. M. HORSBURGH, M.A., Secretary. UNIVERSITY OF GLASGOW. COURSES IN ENGINEERING SCIENCE. ion opens on October 19. ENGINEERING—Prof. ARCHIBALD BARR, D.Sc., M.Inst.C.E. Nava ARCHITECTURE AND Marine ENGINEERING—Prof. J. HARVARD BILES, M.I.N.A. ELECTRICAL ENGINEERING—Mr. JOHN D. CORMACK, B.Sc.,M.1.E.E. ikmastrRy—Prof. JOHN FERGUSON, M.A., LL D. Naturat PurtosopHy—(New Professor to be appointed before opening of Session.) Matuemarics—Prof. WILLIAM JACK, LL.D. GroLocy—Prof. JOHN YOUNG, M.D. Prospectuses of the Courses, with regulations for the Degrees of B.Sc. and DSc. in Engineering Science, and a List of Bursaries and Scholarships opeh to Science Students, can be had from the AssIstTANT CLERK. BIRKBECK INSTITUTION, Breams Buildings, Chancery Lane, E.C. DAY AND EVENING CLASSES. NEW SESSION commences SEPTEMBER 25. UNIVERSITY OF LONDON.—Complete Day Courses for all the Examinations in Science, and Complete Evening Courses for all the Examinations for the Science, Arts, and Law Degrees. SCIENCE CLASSES in every Branch, with Practical Work. Well- equipped Laboratories for Chemistry, Experimental Physics, Biology, Botany, and Metallurgy. LECTURES on Political Economy, Commercial Geography, Common Law, Bankruptcy, Equity and Conveyancing, Logic, Psychology, and Ethics. CLASSES in Languages, Literature, English and Commercial Subjects, and Civil Service. CONJOINT BOARD : Lectures and Practical Work in Chemistry, Physics, Biology, and Practical Pharmacy. SCHOOL OF ART (Day and Evening),—Drawing; Painting, Designing, Modelling, Life Classes, &c. Prospectus and Calendar (6d.), on application to the Secretary. MERCHANT VENTURERS’ TECHNICAL COLLEGE, BRISTOL. PRINCIPAL—Prof. J. WERTHEIMER, B.Sc., B.A. CIVIL AND MECHANICAL ENGINEERING—Prof. J. Munro A.R.S.M., M.I.Mech.E. ELECTRICAL ENGINEERING—Prof. Arnotp Puttip, B.Se., A.R.S.M. CHEMISTRY—Prof. J. WerTHEIMER, B.Sc., B.A. Lecturer—G. P. Darnett SmitH, B.Sc. MATHEMATICS—E. S. Bourton, M.A. In addition to the above the College Staff includes forty Assistant Lecturers, Demonstrators, and skilled Artisans. There are nine labor- atories, seven workshops, a dynamo room, and a large electric light installation. COURSES CIVIL, MECHANICAL, ELECTRICAL AND SANITARY ENGINEERING, AND IN PREPARATION FOR THE BUILDING TRADE. UNIVERSITY OF LONDON—COURSES FOR MATRICULATION AND INT. AND FINAL B.Sc. FEE—TEN GUINEAS A YEAR. Calendar, 6¢., or Short Prospectus (free), on application to the REGISTRAR, HERIOT-WATT COLLEGE, EDINBURGH. Principal, F. GRANT OGILVIE, M.A., B.Sc., F.R.S.E. DAY CLASSES—SESSION 1899-1900. The Session extends from Tuesday, October 3, 1899, to Friday, June 1, 1900. *These Classes provide Courses of Study extending over one or more years, suitable for Students who have previously passed through the Curriculum of a Secondary School. The principal Courses are :—Physical and Chemical, Mechanical Engineering and Electrical Engineering. There are also Classes in French, German, Drawing, and Practice of Commerce. Class Fees, from 41 1s. to £4 4s. Session Fee, £10 ros. There is also a Preparatory Course of Instruction for Agricultural Students. Session Fee, 45 5s. An extract from the Calendar of the College, giving particulars of the Day Classes, and of the various Appliances, Laboratories, and Workshops available for instruction, may be had on application to the LipraRIAN, at the College, or to the TREASURER of George Heriot’s Trust. DAVID LEWIS, Treasurer. Treasurer's Chambers, 20 York Place, Edinburgh, August 1, 1899. THE GLASGOW AND WEST OF SCOTLAND TECHNICAL COLLEGE. The Diploma of the College is granted in the following Departments :— CIVIL ENGINEERING. CHEMICAL ENGINEER- MECHANICAL ENGINEER- ING. ING METALLURGY. NAVAL ARCHITECTURE. MINING. ELECTRICAL ENGINEER- CHEMISTRY. ING. MATHEMATICS AND ARCHITECTURE. PHYSICS. The Courses of Study or the Diploma extend over three Sessions. The Average Fee per Sessionis £rq 14s. Special Courses for individual Students are arranged as required. The Laboratories for Practical Instruction in Physics, Chemistry Technical Chemistry, Metallurgy, Mechanical Engineering, and Electrical Engineering are fully equipped with the most approved Apparatus. The Session opens SEPTEMBER 26. Entrance Examinations begin SEPTEMBER 18. The Calendar (price by Post 1s. 4d.) and Prospectuses (free) will be sent on application to the SECRETARY, 38 Bath Street, Glasgow, ee bi iY sUeeUSiivackn D JOURN OFS Cle NCE. “To the solid ground Of Nature trusts the mind which builds for aye.” —WORDSWORTH. No. 1561, VOL. 60] THURSDAY, SEPTEMBER 28, 18o9. [PRICE SIXPENCE. Registered as a pal at the General Post Office.] [All Rights are Reserved WIRELESS TELEGRAPHY. 1x: wns inh mu il “ THE APPS-NEWTON” INDUCTION COILS made entirely in the London Workshops of NEWTON & CoO., 3S FLEET STREET, E.C., are now used by all the principal experts in Wireless Telegraphy, as well as in Radiography. NEW DOUBLE-SURFACK CONDENSER (CRIBB’S PATENT). Large Condensing Surfaces. Small size of Condenser. Great Efficiency. EQUAL TO A LIEBIG CONDENSER FIVE TIMES ITS SIZE. Small weight. SOLE MAKERS of the Metal Condensers : JOHN J. GRIFFIN & SONS, LE 20-26 SARDINIA STREET, LONDON, W.-C. THE UNIVERSITY EXTENSION MANUALS. Edited by Prof. KNIGHT, of St. Andrews. A SHORT HISTORY OF ASTRONOMY. By ARTHUR BERRY, M.A., Fellow of King’s College, Cambridge ; Secretary to the Cambridge Univers sity Extension Syndicate. With numerous Illustrations. _ 6s. CHAPTERS IN MODERN BOTANY. By PATRICK GEDDES, eter of Botany, University College, Dundee. With Illustrations. 38. 6: THE STUDY OF ANIMAL LIFE. By Ve ARTHUR THOMSON, Lecturer on Zoology, School of Medicine, Edinburgh. With mary Illustrations. 5S. THE REALM OF NA TURE: A Manual OF PiYSIOGRAPHY. By Dr. HUGH ROBERT MILL, Librarian to the Royal Geographical Society. With Nineteen Coloured Maps and Sixty-eight Illustrations. AN INTRODUCTION TO i; MODERN GEOLOGY. By R. D. ROBERTS. With Coloured Maps and Illustrations. THE PHYSIOLOGY OF THE SENSES. By JOHN M‘KENDRICK, Professor of Phys iology i inthe U niversity of Glasgow, and Dr. SNODG RASS, Physiological Labcratory, Glas gow. 45. 6d. A List of the above Series can be obtainec a post free on application. 2 MURRAY, -ALBEM ARLE STREET, W. SPECTACLES FOR ELECTRIC LIGHT, INCANDESCENT GAS, And other Powerful Illuminants. PAX Sew \ | LNE GRE EL) &-Z ANE RAs THERMOSCOPIC LENSES Protect the Eyes from Glare, and RENDER THE LIGHT SOFT AND COOL. Illustrated Price Lists of Optical and Meteorological Instruments Free by Post to all parts af the World. NEGRETTI AND ZAMBRA, SCIENTIFIC INSTRUMENT MAKERS to THE QUEEN, 38 HOLBORN VIADUCT, E.C. BRANCHES : 46 CORNHILL; 122 REGENT STREET, eevi NATURE SEPTEMBER 28, 1899 MASON UNIVERSITY COLLEGE, BIRMINGHAM. DIPLOMA COURSES IN CIVIL, MECHANICAL, AND ELECTRICAL ENGINEERING. Proressor F. W. BURSTALL, M.A. (Camb.), A.M.I.C.E. LecrureER ON TecHNnicAL E.ecrriciry—D. K. MORRIS, Ph.D., A.I.E.E. AssIsSTANT LecTURER AND DEMoNSTRATOR—F. H. HUMMEL, A.M.I.C.E. The Technical Engineering Classes include :— LECTURES on the Strength of Materials, Theory of Steam, Gas, and other Heat Engines, Hydraulics, Machine Design, Strength of Structures, Distribution of Power DRAWING.—Design of Tools, Prime Motors, Dynamos, and other forms of Machinery. FIELD WORK.—Practical Surveying in the Field throughout the Summer Term. ENGINEERING LABORATORY.—Determinations of the Strength of Materials, including Compressive, Bending, Tensile, and Torsion Tests ; Experimental Study of the Steam Engine and Boiler, Frictional Efficiency Tests, the Flow of Water over Weirs and through Orifices, &c. LECTURES and DEMONSTRATIONS on all branches of Electrical Engineering. ELECTRICAL LABORATORY.—Testing of Continuous and Alter- nate Current Machinery, Electrical Instruments, Meters, Lamps, and Batteries, Insulation and Magnetic Testing Work. The Courses also include :— MatHematics—Principal R. S. Hearn, M.A., D.Sc. Puysics—Professor J. H. PoyntinG, D.Sc., F.R.S. CueEmistRY—Professor P. F. FRANKLAND, B.Sc., Ph.D., F.R.S. GroL_oGy—Professor C. Lapwortu, LL.D., F.R.S., F.G.S. Meratturcy—Lecturer, G. MELLAND, B.Sc., A.R.S.M. The DIPLOMA, which carries with it the Associateship of the College, may be obtained at the end of ¢h7ee years’ study. The SESSION 1899-1900 commences on Tuesday, October 3. Professor BURSTALL will attend to consult with intending Students on October 2, from 10 a.m. to 1 p.m. For DETAILED SYLLABUS, with Particulars of Fees, Scholarships, &c., apply to the SECRETARY, QUEEN’S COLLEGE, GALWAY. The Matriculation Examination of Session 1899-1900 commences on OcToBER 20. Matriculation Certificates of any University within the United Kingdom are accepted. All Lectures, Scholarships, Exhibitions, and Prizes are open to Students of either sex. The Scholarship Examinations in Arts, Medicine, and Engineering com- mence on OCTOBER 19. ¥ DEPARTMENTS OF SCIENCE, MEDICINE, AND ENGINEERING. { Prof. ALFRED C. Dixon, .M.A., Sc.D., «1 F.R.U.L, late Fellow of Trinity \ College, Cambridge. { Prof. A. Anperson, M.A,, late Fellow ot +») Sidney Sussex College, Cambridge, \ President of the College. MATHEMATICS PHYSICS ... CHEMISTRY Prof. ALFRED SEnikErR, Ph.D., Berlin. NATURAL HISTORY, ) prog. RicHarp J. ANDERSON, M.A., MINERALOGY, and } Pfc Rican, J: As GEOLOGY... ...J. M-D., M-R.CS., Eng. ENGINEERING... Prof. Epbwarp TownseEnpD, M.A., D.Sc. ANATOMY and BES EO JoserH P. Pye, M.D., M.Ch., OLOGY ... seo aus D.Sc., F.R.U.I. PRACTICE or MEDI-j Prof. Joun Isaac Lynuam, M.D., CINE te are cA M.Ch., M.A.O., F.R.U.I. SURGERY ... a oo)? Ne BreErETON, L.R.C.S.1., MATERIA MEDICA .. (ee eee W. Coroxan, M.D., Prof. RicHarp J. Kuinxkeap, B.A., GYN®COLOGY .. cl RE TEEGIan Prospectus of the Courses and Regulations for Scholarships, &c., can be had on application to the REGISTRAR, Queen’s College, Galway. UNIVERSITY OF GLASGOW. COURSES IN ENGINEERING SCIENCE. The Session opens on October 19. ENGINEERING—Prof. ARCHIBALD BARR, D.Sc., M.Inst.C.E. NAVAL ARCHITECTURE AND MARINE ENGINEERING—Prof. J. HARVARD BILES, M.I.N.A. ELECTRICAL ENGINEERING—Mr. JOHN D. CORMACK, B.Sc.,M.1.E.E. Cuemistry—Prof. JOHN FERGUSON, M.A., LL.D NaTuRAL PuiLosopHy—(New Professor to be appointed before opening of Session.) MatHematics—Prof. WILLIAM JACK, LL.D. GrqLiocy—Prof. JOHN YOUNG, M.D. Prospectuses of the Courses, with regulations for the Degrees of B.Sc. and D.Sc. in Engineering Science, and a List of Bursaries and Scholarshi Qpen to, Scien¢2 Students, can be had from the AsstsTANT CLERK. j _ BIRKBECK INSTITUTION, Breams Buildings, Chancery Lane, E.C. Science Classes with Practical Work. Day and Evening Classes for University of London B.Sc. ; Prelim. Scientific, Inter. M.B. Examination and for Con- joint Board, Dental and Pharmaceutical Examinations. Evening Classes in all stages for Science and Art Depart- ment Examinations. Highly-equipped Laboratories. Chemistry, Physics, Biology (Zoology and Botany), Metal- lurgy, Geology and Mineralogy, Microscopy. Prospectus free. Calendar 6d., Post 8d., on application to Secretary. UNIVERSITY OF ST. ANDREWS. COURSES IN ENGINEERING AT UNIVERSITY COLLEGE, DUNDEE. The Winter Session will commence on October 11. Applicants for Bursaries and Scholarships should give in their names by September 23. ENGINEERING, Prof. T. CLAXTON FIDLER, M. Inst. C.E. Assistant Lecturer in Drawing: Mr. W. A. Tuan, M.I.M.E. PHYSICS. Prof. J. P- KUENEN, Ph.D. Assistant Lecturer and Demonstrator: Mr. J. M‘Cowan, M.A, D.Sc (Electrical Engineering is taken in this Department.) MATHEMATICS. Prof, J. E. A. STEGGAL, M.A., Cambridge. CHEMISTRY. Prof. JAMES WALKER, D.Sc., Ph.D. The Calendar, which can be obtained on application, contains the regu- lations for the degrees of B.Sc. and D.Sc in Engineering, and a list of the Bursaries, which are open to Students of the rst, 2nd, and 3rd year, as well as a Prospectus of the Courses and Laboratory Work. R. N. KERR, Secretary. University College, Dundee, September 5, 1890. UNIVERSITY COLLEGE, LIVERPOOL. (VICTORIA UNIVERSITY.) DEPARTMENT OF ENGINEERING. Session 1899-1900 commences October 2. Complete Courses of Instruction are arranged in (1) Civit ENGINEERING, (2) MECHANICAL ENGINEERING, (3) ELEcTRICAL ENGINEERING. These Courses enable Students to qualify for University Degrees, and for the College Certificates in Engineering. They comprise, in addition to special Engineering Lectures and Laboratory Work, Instruction in Mathe- matics, Physics, Electrotechnics, and Chemistry. H. S. HeLe-Suaw, LL.D., F.R.S., M.Inst.C. E. Lyon Jones Professor of Experi- fOLiver J. Lopcr, D.Sc., F.R.S., iy a S. Carey, M.A., late Fellow of mental Physics... 6 .. (_ M.Inst.E.E. Trinity College, Cambridge. Grant Chair of Chemistry ... +. J. CamprsELt Brown, D.Sc., F.I.C. The special Engineering Prospectus can be obtained on application to the REGISTRAR. Harrison Professor of Engineering { Professor of Mathematics ... UNIVERSITY COLLEGE, LIVERPOOL (VICTORIA UNIVERSITY). SCIENTIFIC DEPARTMENTS. SESSION 1899-1900 will openon MONDAY, OCTOBER 2. PHYSICS ... ... ... .. Prof. Otiver Lopce, D.S§c., F.R.S. CHEMISTRY ... ... Prof. J. CAMPBELL Brown, D.Sc. ZOOLOGY .. Prof. W. A. HErpMaN, D.Sc., F.R.S. BOTANY ... ... ... ... Prof. R. J. HARVEY Gizson, M.A., F.L.S. PHYSIOLOGY ... ... Prof. C. S. Suerrincron, M.A., M.D., F.R.S In addition to Courses preparing for Victoria and London University Degrees, the Laboratories in the above Departments are open to Male and Female Students alike for Study and Research at scales of Fees which can be obtained on application. For full information as to Courses in the Science, Arts, and Medical Departments, apply to the Registrar, E. LONDINI, D.C.L. For other Advertisements of thts character see pages ccvii., ccviil, and ccx, —— A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE, “© To the solid ground Of Nature trusts the mind which builds for aye.” —WORDSWORTH. No. 1562, VOL. 60] THURSDAY, OCTOBER 5, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] (All Rights are Reserved. IRELESS TELEGRAPHY. SS = in HN sl LONGON —= ‘6 THE “APPS-NEWTON” INDUCTION COILS made entirely in the London Workshops of NEVTON & CoO., 3 FLEET STREET, E.C., are now used by all the principal experts in Wireless Telegraphy, as well as in Radiography. BEC K’S | NEW MICROSCOPE THE “BRITISH STUDENTS.” 42a Microscope Stand No. 55, as igured, with Iris Diaphragm, Ine Eye-piece; Double Nose- jiece, Two Object-glasses, 2/3” nd 1/6’, adjusted to be in yhout focus, and the whole yacked in polished Mahogany . £6:8:6 No. 55- R. & J. BECK, Ltd., 68 CORNHILL. LONDON. E.C,. BROWNING’S PLATYSCOPIC LENS. With Larger Angles, Increased Field, and Improved Definition Engraved Real Size. AN ACHROMATIC COMBINATION, COMBINING THE DEFINITION OF A MICROSCOPE WITH THE PORTABILITY OF A POCKET LENS. “Tf you carry a small Platyscopic Pocket Lens (which every observer of Nature ought to do).”—GranT ALLEN in Knowledge. The Platyscopic Lens is invaluable to botanists, mineralogists, or ento | mologists, as it focuses about three times as far from the object as the Coddington Lenses. This allows opaque objects to be examined easily. The Platyscopic Lens is made of four degrees of power, magnifying respectively 10, 15, 20, and 30 diams. ; the lowest power, having the largest field, is the best adapted for general use. The Lenses are set in Ebonite Cells, and mounted in Tortoiseshell Frames. | Price of the Platyscopic Lens, mounted in Tortoiseshell, magnifying either 10, 15, 20, 0” 30 diameters, each power, 15s. In nickelised German Silver, cach power, 17s. 6d. Illustrated Description sent free. JOHN BROWNING, 63 STRAND, LONDON, W.C. SPECTACLES ELECTRIC LIGHT, INCANDESCENT GAS, And other Powerful Illuminants. NEGRETTI & ZAMBRA’S THERMOSCOPIC LENSES Protect the Eyes from Glare, and RENDER THE LIGHT SOFT AND COOL. Illustrated Price Lists of Optical and Meteorological Insty.oréuts Free by Post to all parts of the World. NEGRETTI AND ZAMBRA, SCIENTIFIC INSTRUMENT MAKERS to tHE QUEEN, 38 HOLBORN VIADUCT, E.C. BRANCHES : 46 CORNHILL; 122 REGENT STREET. CCXXil THE DAVY FARADAY RESEARCH LABORATORY OF THE ROYAL INSTITUTION. DIRECTORS: The Right Hon. LORD RAYLEIGH, M.A., D.C.L. LL.D., F.R.S. Professor DEWAR, M.A., LL.D., F.R.S. SUPERINTENDENT OF THE LABORATORY: Dr. ALEXANDER SCOTT, M.A., D.Sc., F.R.S. This Laboratory, founded by Dr. Ludwig Mond, F.R.S., as a Memorial of Davy and Faraday for the purpose of promoting original research in Pure and Physical Chemistry, will be open during the following Terms :— Michaelmas Term.—Monday, October 2, to Saturday, December 16. Lent Term.—Monday, January 8, to Saturday, April 7. Easter Term.— Monday, April 30, to Saturday, July 28. Under the Deed of Trust, workers in the Laboratory are entitled, free of charge, to Gas, Electricity and Water, as far as available, and, at the discretion of the Directors, to the use of the apparatus belonging to the Laboratory, together with such materials and chemicals as may be authorised. All persons desiring to be admitted as workers, must send evidence of scientific training, qualification, and previous experience in original research, along with a statement of the nature of the investigation they propose to undertake. Toes must apply for admission during the course of the preceding erm. Forms of Application can be had from the AssisTaNnT SECRETARY, Roval Institution, Albemarle Street, W. MERCHANT VENTURERS' _ TECHNICAL COLLEGE, BRISTOL. PRINCIPAL—Prof. J. WERTHEIMER, B.Sc., B.A. CIVIL AND MECHANICAL ENGINEERING—Prof. J. Munro A.R.S.M., M.I.Mech.E. ELECTRICAL ENGINEERING—Prof. ArNnotp Pui tp, B.Sc., A.R.S.M. CHEMISTRY—Prof. J. WerTHEIMER, B.Sc., B.A, Lecturer—G. P. DARNELL SmiTH, B.Se. MATHEMATICS—E. S. Boutton, M.A. In addition to the above ithe College Staff includes forty Assistant Lecturers, Demonstrators, and skilled Artisans. There are nine labor- atories, seven workshops, a dynamo room, and a large electric light installation. COURSES IN CIVIL, MECHANICAL, ELECTRICAL AND SANITARY ENGINEERING, AND IN PREPARATION FOR THE BUILDING TRADE. UNIVERSITY OF LONDON—COURSES FOR MATRICULATION AND INT. AND FINAL B.Sc. FEE—TEN GUINEAS A YEAR. Calendar, 6d@., or Short Prospectus (free), on application to the REGISTRAR. GOLDSMITHS’ INSTITUTE, NEW CROSS, S.E. : DEPARTMENT OF CHEMISTRY. EVENING CLASSES, providing complete Courses of Instruction in various branches of Pure and Applied Chemistry, are held at this Institute, under the direction of Mr. WiLL1am Jackson Pope, F.I.C., &c. The Courses of Lectures and Practical Laboratory Teaching are suitable for Students desiring to qualify in Chemistry at the Examinations of the London University, the Pharmaceutical Society, the Science and Art Department, and other Public Bodies. The equipment of the Chemical Laboratories has been recently considerably augmented, and exceptional facilities are offered to Advanced Students who desire to engage in Chemical Research Work during the day or evening. The New Session commences on September 25. For further particulars apply to the Secretary. J. S. REDMAYNE, B.A., Secretary. BALLIOL COLLEGE, CHRIST CHURCH, AND? LRINITY (COLLEGE, OXFORD. NATURAL SCIENCE SCHOLARSHIPS AND EXHIBITIONS. A Combined Examination for Natural Science Scholarships and Exhibi- tions will be held by the above Colleges, beginning on TUESDAY, NOVEMBER 21, 1890. Three Scholarships and Two Exhibitions will be offered, the Scholarships being worth £80 a year. The Subjects for Examination will be Physics, Chemistry, and Biology ; but Candidates will not be expected to offer themselves in more than two of these. Particulars may be obtained by application to Christ Church, Oxford. A. VERNON HARCOURT. CHEMICAL LABORATORY and LEC- TURE ASSISTANT Wanted at once.—Apply Hreap Master, Grammar School, Wolverhampton. NATURE [OcTOBER 5, 1899 | BIRKBECK INSTITUTION. Breams Buildings, Chancery Lane, E.C.} Science Classes with Practical Work. Day and Evening Classes for University of London B.Sc. Prelim. Scientific, Inter. M.B. Examination and for Co} joint Board, Dental and Pharmaceutical Examinations. Evening Classes in all stages for Science and Art Depar ment Examinations. Highly-equipped Laboratories. Chemistry, Physics, Biology (Zoology and Botany), Meta lurgy, Geology and Mineralogy, Microscopy. Prospectus free. Calendar 6d., Post 8d., on application to Secretary. UNIVERSITY OF GLASGOW. COURSES IN ENGINEERING SCIENCE. The Session opens on October 19. ENnGIneEr1inG—Prof. ARCHIBALD BARR, D.Sc., M.Inst.C.E. Nava ARCHITECTURE AND MARINE ENGINEERING—Prof. J. HARVAR BILES, M.I.N.A. ELecrricaL ENGINEERING—Mr. JOHN D. CORMACK, B.Sc.,M.1.E.1 Cuemistry—Prof. JOHN FERGUSON, M.A., LL.D. Naturat PuitosopHy—(New Professor to be appointed before openir of Session.) Matuematics—Prof. WILLIAM JACK, LL.D. Gro.tocy—Prof. JOHN YOUNG, M.D. Prospectuses of the Courses, with regulations for the Degrees of B.Sc. ar D Sc. in Engineering Science, and a List of Bursaries and Scholarshiy open to Science Students, can be had from the Assistant CLERK. THE JENNER INSTITUTE OF PREVENTIVE MEDICINE, CHELSEA GARDENS, CHELSEA BRIDGE, LONDON, S.W. Chairman of Council: Lorp LISTER, P.R.S. The Winter Session will open on Monday, October g, at 4 p.m., whe Dr. ALLAN MacrabyYEN will deliver an Introductory Address. oe. Particulars as to the arrangements for Investigation and Instruction 1 Bacteriology, Chemistry, Hygiene and Technical Bacteriology may t obtained on application to the SECRETARY. INSTRUCTION IN PURE CULTIVATION OF YEAST, According to HANSEN'S Methods. Courses for Beginners, as well as tor Advanced Students, in Physiolo and Technology of Fermentations—Biological Analysis of Yeast. - Manuals:—E. Chr. Hansen: ‘“‘ Practical Studies in Fermentation London (Spon), 1896. Alfred Jérgensen : ‘‘ Micro-organisms and Ferme ation.’” London(F. W. Lyon), 1893. Further Particulars on Application to the Director, ALFRED JORGENSE The Laboratory, Copenhagen. V. BEDFORD COLLEGE, LONDON (FOR WOMEN), YORK PLACE, BAKER STREET, W. HYGIENE AND PUBLIC HEALTH. The Course of Scientific Instruction, Practical and Theoretical, wi begin on Thursday, October 5, and extend over Three Terms. Further information on application to the Principat at the College. B.A. ano B.Sc. MATRICULATION, INTERMEDIATE, FINAL. PREPARATION by CORRESPONDENCE and ORAL TUITIO} ona THOROUGHLY INDIVIDUAL SYSTEM. Fees based on success The STAFF includes Graduates of Oxford, Cambridge, London, an Royal Universities, Science Medallists, Prizemen, Scholars, &c. Lt SINGLE SUBJECTS TAKEN: Latin, Greek, French, German Mathematics, Science, Logic, Psychology, Political Economy, &c. For Terms, &c., address Mr. J, CHARLESTON B.A. (Lond. and Oxon.) The Burlington Classes, 27 Chancery Lane, London, W.C. COACHING. Preliminary Scientific and Inter. M.B., an all other Examinations, MEDICAL and SCIENTIFIC. Well-fittet Laboratories.—" R. C.,” g Heathcote Street, Gray's Inn Road. | A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. ‘© To the solid ground Of Nature trusts the mind which builds Jor aye.” —WORDSWORTH. No. 1563, VOL. 60] THURSDAY, OCTOBER 12, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] va Rights are Reserved. WIRELESS| TELEGRAPHY. THE QUARTERLY REVIEW, . THE FEDERATION OF 7 AG BIGACE LN . PITT AND THE 7. MATTHEW 7. LEONARDO DA VINCI. . THE PENYCUIK EXPERIMENTS. VII. VIII. IX. X. No. 380, WILL BE PUBLISHED ON THE 78th. Price 6s. CONTENTS. AUSTRALIA. THE COUNTRY. FAMILY COMPACT. PRIOR. ((ilustrated.) SCOTT AND HIS PUPILS. NEW LIGHTS ON THE ’45. THE FOOD OF LONDON. WILLIAM MORRIS. “ THE © APPS-NEWTON ” INDUCTION coILs made entirely in the London Workshops of NEW TON & Co., 3S FLEET STREET, are now used by all the principal experts in Wireless Telegraphy, as well as” in Radiography. SHORT BEAM BALANCES > CHEAP, QUICK-ACTINC, ACCURATE, KNIFE EDGES AND PLANES OF AGATE Compensating Stirrup Suspenders. To carry 200, 500 grammes. Price £7. £9 9s. P ASSAY BALANCES. ALUMINIUM BEams. 5 Grammes in each Pan Indicate 7, m.g. £10 10s. and ‘41. CHEMICAL BALANCE. ALUMINIUM BEAM. New design Sliding Rider. To carry 100 250 grms. Indicates 5 qs M.g- £8 15s. _£10 10s. & WRITE for y BALANCE CATALOGUE ‘JOHN J. GRIFFIN & “SONS, [o- 20-26 SARDINIA STREET, LONDON, W.C. E.C., THE NEXT CONCLAVE. A NOTE ON THE PEACE CONFERENCE. THE EMPIRE AND THE TRANSVAAL. XI. XII. XIII. JOHN MU RRAY, ALBEM. ARLE STREET, W. SPECT A CUES. ELECTRIC LIGHT, INCANDESCENT GAS, And other Powerful Illuminants. \NEGRETTI & ZAMBRA’S THERMOSCOPIC LENSES | Protect the Eyes from Glare, and RENDER THE LIGHT SOFT AND COOL. Illustrated Bes Lists of Optical and Meteorological Instruments Free by Post to all parts of the W orld. NEGRETTI AND ZAMBRA, | SCIENTIFIC INSTRUMENT MAKERS to THE QUEEN, 38 HOLBORN VIADUCT, E.C. BRANCHES : 46 CORNHILL; 122 REGEN T STREET. CCXXX1V BACTERIOLOGIST TO THE JOINT COMMITTEE OF THE GLAMORGAN COUNTY COUNCIL, AND CARDIFF CORPORATION, AND LECTURER IN BACTERIOLOGY IN THE UNI- VERSITY COLLEGE, CARDIFF. The Joint Committee is desirous of engaging a Competent BACTERI- OLOGIST who will work in their Laboratory at Cardiff under the direction of the Medical Officers of Health of the Borough and County. Candidates must be able to undertake the Chemical and Bacteriological Examination and Analysis of water, air, soil, sewage, and other effluents ; milk, tuberculous meat, diseased tissues, pathological substances, specimens for the purposes of diagnosis, &c., and other examinations of a like nature. Preference will be given to Candidates with practical experience in the work and management of a Public Health Laboratory and to those pos- sessing high-class qualifications in the various branches of science that are requisite in such a Department. The Appointee’s duties will include all such duties under the said Medical Officers as the Joint Committee may from time to time direct. As Lecturer on Bacteriology in connection with the Medical School of the University College of South Wales and Monmouthshire he must be prepared to undertake the necessary teaching work. For this work he will be responsible to the Joint Committee through the College Authorities. It is the intention of the Joint Committee shortly to provide the Bac- teriologist with an Assistant. The successful Candidate will be required to devote the whole of his time to the duties of the above offices, and will not be entitled to hold any other appointment without the express written permission of the Joint Committee. The Salary as Bacteriologist and Lecturer in Bacteriology is £300 a year. No pension is attached and no payment will be made on account of fees received either for work done in the Laboratory or for teaching work. The Appointment will be terminable at any time by three months’ nctice on either side. Applications, stating age, qualifications, and previous experience, accompanied by copies of not more thad 6 recent testimonials, are :to be received by the undersigned by 10 o'clock a.m. on November 6, 1899. Personal canvassing, direct or indirect, will be a disqualification. W. E. R. ALLEN, Clerk of the Joint Committee. Glamorgan County Offices, Cardiff, October 5, 1890. COUNTY BOROUGH OF GRIMSBY. APPOINTMENT OF LIBRARIAN. The Town Council of the Borough of Grimsby require the services of a HEAD LIBRARIAN for the Public Free Library of the Borough, about to be established, the salary being £105 per annum. Applicants must be experienced men, who have had a training in a Public Library, and they are requested to state their age, qualifications and past ene present occupations, and the earliest date at which they can commence duty. Applications, endorsed ‘‘ LipraRIAN,” accompanied by copies of recent testimonials, not exceeding three in number (which will not be returned), are to be addressed to the Town CLERK, and sent in -not later than Tuesday, the 31st day of October, instant. W. GRANGE, Town Clerk. Town Clerk's Office, Great Grimsby, October 9, 1899. PHILOSOPHICAL SOCIETY OF GLASGOW. THE GRAHAM MEDAL, Awarded for original research in any branch of Chemical Science, IS NOW OPEN TO COMPETITION. Information regarding the conditions under which the award will be made, can be had on application to the SecrETARY of the Philosophical Society, 207 Bath Street, Glasgow. UNIVERSITY OF MELBOURNE. CHAIR OF GEOLOGY AND MINERALOGY. The Council of the University of Melbourne will shortly proceed to the Election of a PROFESSOR of GEOLOGY and MINERALOGY. Applications for the Post, accompanied by testimonials, must be sent to the Office of the AGE? =NERAL FOR Vatenietiey 15 Victoria Street, Westminster, by October 2 1899. Salary. £1000. Further information m: ay be had on applic ation to the AGENT-GENERAL. TRINITY COLLEGE, UNIVERSITY OF DUBLIN. There is a Vacancy for a JUNIOR ASSISTANT and DEMON- STRATOR in the University Chemical Laboratory. The chief duties are preparation of Lecture Experiments and Demon- strations. Salary begins at £100 per annum. Applications, with certificates of experience in work of the same kind, should be sent to Prof. Emerson REYNOLDS, F.R.S., at the Laboratory: the County Must have practical experience in the A gentleman with some knowledge of 4150 per annum.—Apply by letter to Hall, Worcester. REQUIRED.— Assistant “to Analyst for Worcestershire, Analysis of Food and Drugs. Bacteriology preferred. Salary, Mr. Ceciz Duncan, The Shire INAMBOTRE {[OcToBER 12, 1899 BIRKBECK INSTITUTION, Breams Buildings, Chaneery Lane, E.C. Science Classes with Practical Work. DAY AND EVENING CLASSES for University of London B.Sc. ; Prelim. Scientific, Inter. M.B. Examination and for Conjoint Board, Dental and Pharmaceutical Examinations. . EVENING CLASSES in all stages for Science and Art Department Examinations, HIGHLY-EQUIPPED LABORATORIES, Chemistry, Physics, Biology (Zoology and Botany), Metal- lurgy, Geology and Mineralogy, Microscopy. Prospectus free. Calendar 6d. (Post 8d.) on application to Secretary. UNIVERSITY COLLEGE, LONDON. THE MANIPULATION OF GASES, BY MORRIS W. TRAVERS, D.Sc. A Course of Six Lectures will commence on Friday, November 10, at 5-30 o'clock. Syllabus on application to the SEcrerary, University College, London, Gower Street, W.C. LIVERPOOL SCHOOL OF TROPICAL MEDICINE IN CONNECTION WITH UNIVERSITY COLLEGE AND ROYAL SOUTHERN HOSPITAL. MAJOR ROSS, late I.M.S. For prospectus and all particulars, apply to A. H. MILNE, B. As Hon. Sec., ORES of Cops Liverpool. B.A. ano B.Sc. MATRICULATION, INTERMEDIATE, FINAL. PREPARATION by CORRESPONDENCE and ORAL TUITION ona THOROUGHLY INDIVIDUAL SYSTEM. Fees based on success. The STAFF includes Graduates of Oxford, Cambridge, London, and Royal Universities, Science Medallists, Prizemen, Scholars, &c. SINGLE SUBJECTS TAKEN: Latin, Greek, French, German, Mathematics, Science, Logic, Psychology, Political Economy, &c. For Terms, &c., address Mr. J. CHARLESTON B.A. (Lond. and Oxon.), The Burlington Classes, 27 Chancery Lane, London, W.C. Lecturer B.A., PRELIMINARY SCIENTIFIC, B.Sc., and all other EXAMS. QUERNMONRE. London Branches—(1) 24 CHANCERY LANE, W.C.; (2) 115 EBURY STREET, EATON SQUARE S.W Special Preparation by JOHN GIBSON, M.A. (First Class, Cambridge) and G. LOLY, B.A. (First Class, London), assisted by large Staff of Specialist Tutors. Practical Laboratories. Write for particulars to Messrs. Gisson & Lory, 24 Chancery Lane, W.C. Telegrams—‘‘ Tunzelmann, London. THE ELECTRICAL AND GENERAL ENGINEERING COLLEGE. PRESIDENT-G. W. DE TUNZELMANN, B.Sc. Lond., M.I.E.E. PrincipaL—J. H. REEVES, M.A. Cantab. Next SESSION begins WEDNESDAY, SEPTEMBER 27. Particulars on application to the SECRETARY, 2 and 4 Penywern Road, Earl's Court, S.W. RESEARCH. CHEMISTRY. PHYSICS. — BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. y,immersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Currents, both Con- stant and Alternating ; also Experimental Motor and Dynamo.—“ T.,’ g Heathcote Street, Gray's Inn Road. A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. “ To the solid ground Of Nature trusts the mind which builds for aye.” —WORDSWORTH. No. 1564, VOL. 60] THURSDAY, OCTOBER 19, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.) {All Rights are Reserved. et OF EW LANTERN SLIDES. SEASON 1899-1900. The Transvaal and the War. St. Paul’s Cathedral The Thames. Flower Studies. Australia—up Country. Meteorology. Lang's Fairy Tales. Alice through the Looking-glass. Stations of the Cross from Wood Vireless Telegraphy. ,stronomical- Works in the Solar Physics Observatory. dlements of Agriculture—Cattle and Wheat. , . 3irds and Animals, by R. B. LopceE. jpiders, Insects, and Butterflies. -anterbury—the City and Cathedral Shina—Burma. a Malay Archipelago. Carvings 3 National and Tate Gallery. Chinese Illustrations of Bible 3elgium. Stories. &c., &c. Knowledge Series, Astronomy. Full detailed List of Lanterns and Slides on application, Six Stamps. NEWTON & CO., BEC kX’ NEW MICROSCOPE THE “BRITISH STUDENTS.” Microscope Stand No. 55, as figured, with Iris Diaphragm, One Eye-piece; Double Nose- piece, Two Object-glasses, 2/3” and 1/6”, adjusted to be in about focus, and the whole packed in polished Mahogany Case, £6:8:6 No. 55. R. & J. BECK, Ltd., 68 CORNHILL. LONDON. E.C, BROWNING’S PLATYSCOPIC LENS. With Larger Angles, Increased Field, and Improved Definition Engraved Real Size. AN ACHROMATIC COMBINATION, COMBINING THE DEFINITION OF A MICROSCOPE WITH THE PORTABILITY OF A POCKET LENS. ‘© Tf you carry a small Platyscopic Pocket Lens (which every observer of Nature ought to do).”—GraNnT ALLEN in Knowledge. The Platyscopic Lens is invaluable to botanists, mineralogists, or entc- mologists, as it focuses about three times as far from the object as the Coddington Lenses. This allows opaque objects to be examined easily. The Platyscopic Lens is made of four degrees of power, magnifying respectively 10, 15, 20, and 30 diams. ; the lowest power, having the largest field, is the best adapted for general use. The Lenses are set in Ebonite Cells, and mounted in Tortoiseshell Frames. Price of the Piatyscopic Lens, mounted in Tortoiseshell, magnifying either 10, 15, 20. or 30 diameters, each power, 15S. In nickelised German Silver, each power, 17s. 6d. Illustrated Description sent free. JOHN BROWNING, 63 STRAND, LONDON, W.C > SPECTACLES ELECTRIC LIGHT, INCANDESCENT GAS, And other Powerful Illuminants. NEGRETTI & ZAMBRA’S THERMOSCOPIC LENSES Protect the Eyes from Glare, and RENDER THE LIGHT SOFT AND COOL. Illustrated Price Lists of Optical and Meteorological Instruments Free by Post to all parts of, the World. | NEGRETTI AND ZAMBRA, | SCIENTIFIC INSTRUMENT MAKERS to THE QUEEN, 38 HOLBORN VIADUCT, E.C. \ | BRANCHES: 45 CORNHILL; 122 REGENT STREET. { r ecxlvi THE DAVY FARADAY RESEARCH LABORATORY OF THE ROYAL INSTITUTION. DIRECTORS: The Right Hon. LORD RAYLEIGH, M.A., D.C.L. LL.D., F.R.S. Professor DEWAR, M.A., LL.D., F.R.S. SUPERINTENDENT OF THE LABORATORY : Dr. ALEXANDER SCOTT, M.A., D.Sc., F.R.S. This Laboratory, founded by Dr. Ludwig Mond, F.R.S., as a Memorial ef Davy and Faraday for the purpose of promoting original research in Pure and Physical Chemistry, will be open during the following Terms :— Wichaelmas Term.—Monday, October 2, to Saturday, December 16. Lent Term.—Monday, January 8, to Saturday, April 7. Easter Term.— Monday, April 30, to Saturday, July 28. Under the Deed of Trust, workers in the Laboratory are entitled, free of charge, to Gas, Electricity and Water, as far as available, and, at the discretion of the Directors, to the use of the apparatus belonging to the ‘Laboratory, together with such materials and chemicals as may be authorised. AJl persons desiring to be admitted as workers, must send evidence of scientific training, qualification, and previous experience in original «esearch, along with a statement of the nature of the investigation they propose to undertake. meter must apply for admission during the course of the preceding erm. Forms of Application can be had from the Assistant SECRETARY, Roval Institution, Albemarle Street, W. BACTERIOLOGIST TO THE JOINT COMMITTEE OF THE GLAMORGAN COUNTY COUNCIL, AND CARDIFF CORPORATION, AND LECTURER IN BACTERIOLOGY IN THE UNI- VERSITY COLLEGE, CARDIFF. The Joint Committee is desirous of engaging a Competent BACTERI- ‘OLOGIST who will work in their Laboratory at Cardiff under the direction of the Medical Officers of Health of the Borough and County. Candidates must be able to undertake the Chemical and Bacteriological Examination and Analysis of water, air, soil, sewage, and other effluents ; milk, tuberculous meat, diseased tissues, pathological substances, specimens for the purposes of diagnosis, &c., and other examinations of a like nature. Preference will be given to Candidates with practical experience in the work and management of a Public Health Laboratory and to those pos- sessing high-class qualifications in the various branches of science that are requisite in such a Department. The Appointee’s duties will include all such duties under the said Medical “Officers as the Joint Committee may from time to time direct. As Lecturer on Bacteriology in connection with the Medical School of ithe University College of South Wales and Monmouthshire he must be prepared to undertake the necessary teaching work. For this work he will be responsible to the Joint Committee through the College Authorities. It is the intention of the Joint Committee shortly to provide the Bac- teriologist with an Assistant. The successful Candidate will be required to devote the whole of his time to the duties of the above offices, and will not be entitled to hold any other appointment without the express written permission of the Joint Committee. The Salary as Bacteriologist and Lecturer in Bacteriology is £300 a year. No pension is attached and no payment will be made on account of fees received either for work done in the Laboratory or for teaching work. The Appointment will be terminable at any time by three months’ nctice on either side. Applications, stating age, qualifications, and previous experience, accompanied by copies of not more thad 6 recent testimonials, are to be received by the undersigned by 10 o'clock a.m. on November 6, 1899. Personal canvassing, direct or indirect, will be a disqualification. W. E. R. ALLEN, Clerk of the Joint Committee. Glamorgan County Offices, Cardiff, October 5, 1899. UNIVERSITY OF MELBOURNE. | CHAIR OF GEOLOGY AND MINERALOGY. ® The Council of the University of Melbourne will shortly proceed to the Election of a PROFESSOR of GEOLOGY and MINERALOGY. Applications for the Post, accompanied by testimonials, must be sent to the Office of the AGENT-GENERAL FoR Victoria, 15 Victoria Street, Westminster, by October 20, 1899. Salary, £1000. Further information may be had on application to the AGENT-GENERAL. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. ysimmersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Currents, both Con- stant and Alternating ; also Experimental Motor and Dynamo.—“ T.,’ 9 Heathcote Street, Gray's Inn Road. NATURE [OcTOBER 19, 1899 BIRKBECK INSTITUTION, Breams Buildings, Chaneery Lane, E.C Science Classes with Practical Work. DAY AND EVENING CLASSES for University London B.Sc. ; Prelim. Scientific, Inter. M.B. Examinatii and for Conjoint Board, Dental and Pharmaceuti Examinations. EVENING CLASSES in all stages for Science and Department Examinations. HIGHLY-EQUIPPED LABORATORIES. | Chemistry, Physics, Biology (Zoology and Botany), Metal lurgy, Geology and Mineralogy, Microscopy. . Prospectus free. Calendar 6d. (Post 8d.) on application to Secretary. CITY AND GUILDS TECHNICAL COLLEGE, LEONARD STREET, FINSBURY, E.C. A Special Course of Seven Lectures on LENSES and PRISMS will bi delivered by Prof. Sy_vanus P. THompson, 1).Sc., F.R.S., on Frida Evenings, at 8 o'clock, beginning on Friday, October 27. Fee for the Course, 7s. Apprentices under 20 years of age admitted ati} half fees. Syllabus of the Lectures and Programme of the College may be obtainee at the College, Leonard Street, City Road, or at the Head Office of the Institute, Gresham College, Basinghall Street, E.C. JOHN WATNEY, Honorary Secretary of the Institute. B.A. ano B.Sc. MATRICULATION, INTERMEDIATE, FINAL. PREPARATION by CORRESPONDENCE and ORAL TUITION ona THOROUGHLY INDIVIDUAL SYSTEM. Fees based on success. The STAFF includes Graduates of Oxford, Cambridge, London, and Royal Universities, Science Medallists, Prizemen, Scholars, &c. SINGLE SUBJECTS TAKEN: Latin, Greek, French, German, Mathematics, Science, Logic, Psychology, Political Economy, &c. For Terms, &c., address Mr. J. CHarteston B.A, (Lond. and Oxon.), The Burlington Classes, 27 Chancery Lane, London, W.C. Telegrams—*‘ Tunzelmann, London.” THE GENERAL ENGINEERING COMPANY, LTD., 2 and 4 PENYWERN ROAD, LONDON, S.W. G. W. p—E TUNZELMANN, Managing Director. Mechanical, Electrical and Chemical Patents experimentally developed and Models constructed for Inventors. Special Machinery and Apparatus designed and carried out to Specification. Every description of Accurate work. Repetition work with all parts interchangeable. REQUIRED.— Assistant to the County Anaiyst for Worcestershire. Must have practical experience in the Anzlysis of Food and Drugs. A gentleman with some knowledge of Bacie‘iology preferred. Salary, £150 per annum.—Apply by letter to Mr. Ceci, Duncan, The Shire Hall, Worcester. WANTED, an ASSISTANT and DEMON- STRATOR for the Laboratory of the EDINBURGH ACADEMY. Knowledge of Physics as well as Chemistry important. Salary, £80,— Apply, by letter, to J. TupoR CunpALL, Academy, Henderson Row, Edinburgh. COACHING. Preliminary Scientific and Inter. M.B., and all other Examinations, MEDICAL and SCIENTIFIC. Well-fitted Laboratories.—‘‘ R. C.,"’ g Heathcote Street, Gray's Inn Road. Demonstratorship of Physiology.—Appli- cations to Dr. WaLLer, St. Mary’s Hospital Medical School, For Sale, 42 Vols. of ‘‘ Nature,” xvii.-lvi., bound Cloth ; lvii. and lviii., unbound.—Offers to Dr. Jones, Wath yg) Rotherham. Paddington, W. a WEEKLY ILEUSTRATED JOURNAL OF SCIENCE. “< To the solid Of Nature trusts the mind which grouna builds for aye.”’—WORDSWORTH. No. 1565, VOL. 60] THURSDAY, OCTOBER 26, 1899. [PRICE SIXPENCE. Registered as a Newspaper at the General Post Office.] [All Rights are Reserved. ‘LIST OF NEW LANTERN SLIDES. SEASON 1899-1900. The Transyaal and the War. St. Paul’s Cathedral. The Thames. Flower Studies. Australia—up Country. Meteorology. ang’s Fairy Tales. Alice through the Looking-glass. Stations of the Cross from Wood Carvings Chinese Bible Stories. Wireless Telegraphy. Astronomical Works in the Solar Physics Observatory. Elements of Agriculture—Cattleand | Wheat. Birds and Animals, by R. B. Lopce. Spiders, Insects, and Butterflies. Canterbury—the City and Cathedral China—Burma. Malay Archipelago. National and Tate Gallery. Belgium. Illustrations of Knowledge Series, Astronomy. Full detailed List of Lanterns and Slides on application, Six Stamps. NEWTON & CO., SRERET STREET, E:G; GRIFFIN’S NEW FORM OF APPARATUS For the ABSOLUTE EXPANSION OF SOLIDS— (Weedon’'s Patent). One great merit in the design of this Apparatus is that it is 2 Teas Mechanical method, and do ot depend at all upon Optical methods of magnification that so frequently are a difficulty in early Practical Physics work, The measurement reduces itself to the readings of two Aficrometer Scrvews. A DIRECT MECHANICAL METHOD. ABSOLUTE READINGS OBTAINED. SIMPLEST DESIGN. Write for Particulars and Specimen Curves obtained. SOLE MAKERS: JOHN J. GRIFFIN & SONS, 20-26 SARDINIA STREET, LONDON, W.C. |THE REALM OF NATURE: A SELECTION FROM THE UNIVERSITY EXTENSION MANUALS. Edited by Prof. KNIGHT, of St. Andrews. A SHORT HISTORY OF ASTRONOMY. By ARTHUR BERRY, M.A., Fellow of King’s College, Cambridge ; Secretary to the Cambridge University Extension Syndicate. With numerous Illustrations. 6s. CHAPTERS IN MODERN BOTANY. By PATRICK GEDDES, Professor of Botany, University College, Dundee. With Illustrations. © 3s. 6d. THE STUDY OF ANIMAL LIFE. By J. ARTHUR THOMSON, Regius Professor of Natural History in the University of Aberdeen. With mary Illustrations. 5s. A Manual HUGH ROBERT MILL, With Nineteen of PHYSIOGRAPHY. By Dr. Librarian to the Royal Geographical Society. Coloured Maps and Sixty-eight Illustrations. 58+ /AN INTRODUCTION TO MODERN Fee es: ey R. D. ROBERTS. With Coloured Maps and THE PHYSIOLOGY OF THE SENSES. By JOHN M‘KENDRICK, Professor of Physiology in the University ot Glasgow, and Dr. SNODGRASS, Physiological Laboratory, Glasgow. 4s. 6d. A List of the above Serie JOHN MURRAY, ALBEMARLE STREET, W. SPECTACLES FOR ELECTRIG LIGHT, INCANDESCENT GAS, And other Powerful Illuminants. Fy s can be o ined post free on application. . ) aN S \ 'NEGRETTI & ZAMBRA’S | THERMOSCOPIC LENSES Protect the Eyes from Glare, and RENDER THE LIGHT SOFT AND COOL. Illustrated Price Lists of Optical and Meteorological Instruments, Free by Post to all parts of the World. NEGRETTI AND ZAMBRA, | SCIENTIFIC INSTRUMENT MAKERS to THE QUEEN, 38 HOLBORN VIADUCT, E.C. BRANCHES ; 46 CORNHILL; 122 REGENT STREEY. ccliv BACTERIOLOGIST TO THE JOINT COMMITTEE OF THE GLAMORGAN COUNTY COUNCIL, AND CARDIFF CORPORATION, AND LECTURER IN BACTERIOLOGY IN THE UNI- VERSITY COLLEGE, CARDIFF. The Joint Committee is desirous of engaging a Competent BACTERI- OLOGIST who will work in their Laboratory at Cardiff under the direction of the Medical Officers of Health of the Borough and County. Candidates must be able to undertake the Chemical and Bacteriological Examination and Analysis of water, air, soil, sewage, and other effluents ; milk, tuberculous meat, diseased tissues, pathological substances, specimens for the purposes of diagnosis, &c., and other examinations of a like nature. Preference will be given to Candidates with practical experience in the work and management of a Public Health Laboratory and to those pos- sessing high-class qualifications in the various branches of science that are requisite in such a Department. The Appointee’s duties will include all such duties under the said Medical Officers as the Joint Committee may from time to time direct. As Lecturer on Bacteriology in connection with the Medical School of the University College of South Wales and Monmouthshire he must be prepared to undertake the necessary teaching work. For this work he will be responsible to the Joint Committee through the College Authorities. It is the intention of the Joint Committee shortly to provide the Bac- teriologist with an Assistant. The successful Candidate will be required to devote the whole of his time to the duties of the above offices, and will not be entitled to hold any other appointment without the express written permission of the Joint Committee. The Salary as Bacteriologist and Lecturer in Bacteriology is £300 a year. No pension is attached and no payment will be made on account of fees received either for work done in the Laboratory or for teaching work. __ The Appointment will be terminable at any time by three months’ notice on either side. 9 Applications, stating age, qualifications, and previous experience, accompanied by copies of not more thad 6 recent testimonials, are to be received by the undersigned by 10 o'clock a.m. on November 6, 1899. Personal canvassing, direct or indirect, will be a disqualification. W. E. R. ALLEN, Clerk of the Joint Committee. Glamorgan County Offices, Cardiff, October 5, 1809. APPLICATIONS (addressed to the MINISTER OF EpucaTIoN, Toronto, Ontario, Canada) will be received up to January 1, 1900, for the position of PROFESSOR of CHEMISTRY in the University of Toronto. The Salary attached to the position is 2500 dols., rising by annual increments to 3200 dols, For further particulars address Dr. W. H. Pike, care of the High Com- missioner for Canada, London, E.C., or the PRESIDENT, University of Toronto, Toronto. October, 1899. CIVIL SERVICE COMMISSION. FORTHCOMING EXAMINATION. ASSISTANT in the NAUTICAL ALMANAC OFFICE of ADMIRALTY (1&-25), DECEMBER 14. The date specified is the latest at which applications can be received. They must be made on forms to be obtained, with particulars, from the SECRETARY, Civil Service Commission, London, S.W. TECHNICAL COLLEGE, HUDDERSFIELD. PRINCIPAL—S. G. RAWSON, D.Sc. Applications are invited, not later than November 13, for the newly- founded Lectureship in Latin and Greek. Salary 4150 per annum. Further particulars may be obtained upon application. THOS. THORP, Secretary. ASSISTANT WANTED FOR PRIVATE PHYSICAL LABORATORY in Glasgow. Mechanical and Theo- retical Qualifications desirable. Facilities for Research.—Apply, stating experience and remuneration expected, to ‘ X.Y.Z.,” Byres ROR OEE Ss PRACTICAL PLANE AND SOLID GEOMETRY. MACHINE CONSTRUCTION AND DRAWING. A Firm of Publishers invites Offers from Specialists in the above subjects for the preparation of Text-books to meet the requirements of the Science and Art Department,—Apply, stating qualifications fully, to ‘‘S. W. N.,” c/o Hart's Advertising Offices, Maltravers House, Arundel Street, Strand. RESEARCH. CHEMISTRY. PHYSICS. BACTERIOLOGY. Well-fitted LABORATORIES can be used for RESEARCH at any hour convenient to Workers. Dark Room for PHOTOGRAPHIC and other Work. yximmersion for MICRO-PHOTOGRAPHY. Workshop for making Apparatus. ELECTRIC MAINS, powerful Currents, both Con- stant and Alternating; also Experimental Motor and Dynamo.—‘“‘T.,” 9 Heathcote Street, Gray's Inn Road. the For Sale, 42 Vols. of ‘‘ Nature,” xvii.-lvi., bound Cloth ; lvii. and lviii., unbound.—Offers to Dr. Jones, Wath, Rotherham. \ ¥B1 0% NADUKE [OCTOBER 26, 1899 LONDON COUNTY COUNCIL. TECHNICAL EDUCATION BOARD. LECTURES ON SEWAGE AND ITS PURIFICATION. A Course of Twelve Lectures, by Dr. S. Ripeat, #.1.C., will be de livered at University College, Gower-street, W.C., on Mondays at 5.3 commencing November 6. 3 _ For particulars apply to the SECRETARY of the College or to the unde: signed. WM. GARNETT, Secretary of the B: 7 116 St. Martin’s Lane, W.C. i ashen psc UNIVERSITY COLLEGE, LONDON. THE MANIPULATION OF GASES, BY MORRIS W. TRAVERS, D.Sc. A cones of Six Lectures will commence on Friday, November 10, i 5-30 OCIOCK. Syllabus on application to the SEckETARY, University College, Londo: Gower Street, W.C. St y ge, 1 B.A. ano B.Sc. MATRICULATION, INTERMEDIATE, FINAL. PREPARATION by CORRESPONDENCE and ORAL TUITIO on a THOROUGHLY INDIVIDUAL SYSTEM. Fees based on succes The STAFF includes Graduates of Oxford, Cambridge, London, an Royal Universities, Science Medallists, Prizemen, Scholars, &c. | SINGLE SUBJECTS TAKEN: Latin, Greek, French, Germai Mathematics, Science, Logic, Psychology, Political Economy, &c. For Terms, &c., address Mr. J. CHARLESTON B.A. (Lond. and Oxon.) The Burlington Classes, 27 Chancery Lane, London, W.C. a LONDON MATRICULATION AND HOSPITAL SCHOLARSHIPS. QUERNMORE. Special Preparation for the above, Privately, in Class, or by Corr spondence, by Messrs. JOHN GIBSON (First Class, Cambridge) and G LOLY (First Class, London), with large Staff of Specialist Tutors. Resider Pupils received at Upper Norwood. Long list of successes on applicatior N.B.—The London Matriculation Guide, with Examination Papers an Solutions (price 1s.), is issued each January and June. Address: Messrs. GIBSON & LOLY, 24 Chancery Lane, W.C. Telegrams—‘‘ Tunzelmann, London.”’ THE ELECTRICAL AND GENERAL ENGINEERING COLLEGE. PRESIDENT—G. W. pE TUNZELMANN, B.Sc. Lond., M.I.E.E. Principat—J. H. REEVES, M.A. Cantab.? Next SESSION begins WEDNESDAY, SEPTEMBER 27. articulars on application to the SECRETARY, 2 and 4 Penywern Roa Earl's Court, S.W. - COACHING. Preliminary Scientific and Inter. M.B., an all other Examinations, MEDICAL and SCIENTIFIC. Well-fitter Laboratories.—‘‘ R. C.,”. g Heathcote Street, Gray’s Inn Road. PATENTS. JAMES G. LORRAIN, M.LE.E., M.I.MECH.E., &c., CHARTERED PATENT AGENT, Norfolk House, Norfolk Street, LONDON, W.C. Speciality-PHYSICAL PATENTS, OPPOSITIONS, AND AMENDMENTS Charges on Application. Telephone No. 2511 GERRARD. Telegrams: ‘‘ LorRAIN, LONDON! “*Patentees’ Handbook”’ Post free on application, GLASS BLOWING. Blowing carried out for Scien- tific Men, Laboratories, &c. INVENTORS’ InEAS Workeo OUT AS PER __ INSTRUCTIONS. COSSOR, 67 Farringdon Road, E.C. 7S if ‘ on, vag a i t in iii | vt 3 9088 01359 ole | | | ee eetines Seleleeactesenet amen hnt eee O88