mmWmmmMmmm^ 7^ ^ SIMPLY WORDED-EXACTLY DESCRIBED. Founded by RICHARD A. PROCTOR. 7) 6, HIGH HOLBOFN. W.C. 6< I KNOWLEDGE, ui. INDEX. Aeronautical Annuad, The, 1897 — Review of ... ... . .. ■. 168 Airy, Sir George Biddell, Autobiograpiiy of— Edited by W. Aiby, Eeview of 28 Alchemy, Modern — ByW. E. Ord 285 Alger, T. L., LL.D., Ph.D.— The Spectrum Top 8 Andree, Herr — Balloon Expedition to the North Pole, Note on 1«7 Animal Life in Arctic Regions— By P\ W. Headley 21 Animals, Domestic. The Origin of Some— By R. Lydekker ... ... ... ... 63 Animals— List of the Vertebrate, noic or lately living in the Gardens of tlie Zoological Society, Review of ... " 31 Antivenene, More about — By Dr. J. G. McPherson 205 Letters on ; by Lionel Jervis ... 237,261 Antoniadi, E. M. — The Hourglass Sea on Mars 169 Archaeological Survey of the United Kingdom — By l3.vviD Murray, Review of ... . . 88 Aristarchus and the Sinus Iridum— By E. W. Maunder 142 Ascent of Man, The — By Henry Drumiiond, Review of ... ... 299 Astronomical Museum, A National — Letter on ; by G. E. L.w alette ... ... 188 Letter on; by E. W. Maunder 189 Astronomical Observations and Researches made at Dunsink— Review of ... ... ... ... ... 115 Astronomical Photography — By F. L. 0. Wadsworth 193,218 Astronomical Research, Sixty Years of— By Agnes M. Clerke ... ... ... ... 34 Astronomical Tables — By H. Gratt.^n Guinness, Review of ... 280 Astronomy, Elements of— By Sir Robert Ball, Eeview of ... ... 32 Astronomy, Elements of Descriptive- By Herbert A. Howe, Review of ... ... 298 Aurora Borealis — By Alfred Angot, Eeview of .. ... ... 214 Australasia, On the Vegetation and Some of the Vegetable Productions of — By W. BoiTiNG Hemsley ... 66,118,161,242 Letter on ; by F. Whittebon ... ... 212 Note on 237 Australia, The Naturalist in — ByW. S.wille-Kent, Review of .. ... 190 Bacillus in Coal — Letter on ; by G. W. Bulman ... ... 60 Backhouse, T. W.— Letters on Star Systems ... ... 51, 99, 164 Bainbridge, Reginald — Letter on Biela's Comet ... ... ... 262 Balloons, Measuring Altitude of — Note on 294 Banks, Journal of the Right Hon. Sir Joseph— By Sir Joseph Hooker, Eeview of . . . ... 68 Bartlett, A. D.— Obituary Notice of ... 139 Bears, Polar, at the " Zoo "' — By F. E. Beddard 39 Beaver in Norway, The— By R. Lydekker ... .. ... ... 295 Beddard, F. E., F.R.S.— The Polar Bears at the " Zoo " Bee, The Leaf-Cutter— Letters on ; by Fred, Enock Letters on ; by F, M. Duncan Beet Sugar Industry of France — Note on 39 13, 72 51, 99 14 Beetle Collector's Handbook, The Young— By Dr. E. HoF.MA.vx, Eeview of 238 Beetle, The Common Tiger, Life History of— By Fred. Enock 73 Besley, W. E. Letter on Mira Ceti ... ... 100 Biela's Comet- Letter on ; by Regd. Baintbridge ... ... 262 Note on ; by E. Walter Maunder ... ... 262 Bio-Chemical Laboratory, Handbook for the — By Prof. J. A. Mandel, Review of 69 Biological Experimentation : its Functions and Limits — By Sir B. W. Richardson, Review of ... 26 Biological Progress in the Victorian Era— By R. Lydekker ... ... ... ... 110 Biology, Lessons in Elementary — By T. Jeffeby Parker, Review of 298 Biology, Problems of— By G. S.\ndeman, Review of 70 Bird-Calls, Alphabetical List of— Note on 294 Bird Life— By Frank M. Ch.apm.\n, Review of 279 Bird-Song, Evolution of— By C. A. WrrcHELL, Review of 30 IV. KNOWLEDGE Bird-Songs in Autumn — By C. A. WiTCHELL Bird -Songs in Spring- By C. A. \VlTCHEI.L Bird-Songs in Summer— Bv C. A. WiTCHELL Bird-Songs in Winter — By C. A. WiTCHELL ... Letter on ; by C. A. Witchell Birds, A Dictionary of — By Prof. A. Newton, Eeview of Birds. British, A Concise Handbook of— By H. K. SwANN, Review of Birds, British, An Illustrated Manual of— By Howard Saunders, Keview of Birds. North American, Life Histories of— By Charles Bendire, Keview of Birds. International Congress on Protection of— Letter on ; by M. L. Lemon ... Birds of Oban's Isles — By Harry F. Witherby Birds of our Country — By 11. E. Stewart, Eeview of Birds of our Islands— By F. A. FuLCHER, Review of Birds, Society for Protection of— Educational Leaflets, Review of Blaine, Robert Gordon, M.E., Assoc.M.Inst.C.E.— Progress in Mechanical Science during the Queen's Reign Book Table. Our Books and Periodicals, Short Notices of — PAGE 225 81 157 17 262 190 32 298 215 292 221 214 191 29 132 25 Amateur Observer's Almanack, The, 1897 — Arthur Mee ... ... ... ... ... 48 Arch of Titus, The— William Knight ... ... 32 Art of Extempore Speakmg, The — Harold Ford ... 32 Art of Projection and Complete Magic Lantern Manual ... ... ... ... ... 97 Artistic Landscape Photography — A. H. Wall ... 49 Astronomical Chart ... ... ... ... 32 Biological Problem of To-Day, Tlie— Oscar Hertwig 70 Bond, William Cranch, Memorials of ... ... 238 British Guiana and its Resources ... ... 32 British Patent Law — Hubert Haes ... ... 71 Celestial Motions — W. T. Lynn ... ... ... 142 Cliild's History of Scotland^ A —Mrs. Oliphant ... 32 Confidences of an Amateur Gardener — A. M. Dew- Smith ... ... ... ... ... 215 Earth, The, and its Story^Angelo Heilprm ... 97 Elementary Decoration as applied to the Decora- tion of Dwelling Houses— James William Facey 32 Elements of Chemistry — Rufus P. Williams ... 299 Elements of General Philosophy — George Groom Robertson ... ... ... ... ... H7 Elements of Physics, The— Ed. L. Nichols and W. S. Franklin ... ... ... .. 70, 216 English Literature from a.d. 670 to a.d. 1832 — Stoitlord A. Brooke ... ... ... ... 169 Era of Light — I. G. Ouseley ... ... ... 71 European Architecture— Russell Sturgis ... 117 Everybody's Guide to Photography . ... 142 Exterior and Interior Photography— F. W.Mills... 142 Fruit Culture for Amateurs— S. T. Wright ... 141 Fuel and Refractory Materials — A. Humboldt Sexton ... ... ... _ 72 Geology of North-East Durham— D. A. Woolacott 238 Greenwood's Library Year Book ... ... ... 97 PA8E History of Mankind, The— F. Ratzel ... ... 141 Induction Coils and Coil-Making— F. C. Allsop ... 97 Insects and Spiders— J. W. Tutt ... ... 49 Ireland— R. Barry O'Brien ... ... ... 117 Is the Earth a Planet ?—C. Robertson ... ... 215 Italian Highways — E. Augusta King ... ... 192 Library, The, 1896 ... ... ... ... 32 Light as the Interjjretatiou of the Law of Gravity — Alexander M. Cameron ... ... ... 141 Literary Year Book, The, 1S97— F. G. Atlalo ... 117 Literature of Music, The — James E. Matthew ... 97 Manual of Ethics— John S. Mackenzie ... ... 299 Manual of Mending and Repairing, A — Charles Godfrey Lcland ... ... ... ... 33 Model Drawing and Shading from Casts- — T. C. Barfield ... ... ... ... ... 32 Model Locomotive Engineer — Michael Reynolds ... 32 Modern Optical Instruments^Henry Orford ... 71 Months, The, descriptive of the Successive Beauties of the Year — Leigh Hunt ... ... ... 169 Oiu- Place among Infinities— Richard A. Proctor... 215 Our Weights and Measures — H. J. Chancy ... 216 Outlines of Physics— Edward L. Nichols ... 299 Photogram, The (January) ... ... ... 49 Photo-Trichromatic Printing — C. G. Zander ... 32 Physics Note Book— J. C. P. Adolphus ... ... 71 Practical Astrology — Alan Leo ... ... ... 238 Practical Electricity— W. E. Ayrton ... ... 215 Practical Histology — Edward Albert Schafer ... 299 Practical Wort in Physics^ W. G. WooUcombe ... 49 Private Libraries, List of ... ... ... 97 Progi'ess in Printing and tlie Graphic Arts during the Victorian Era — John Southward ... ... 299 Queen's London, The ... ... ... ... 238 Pocks and Minerals— J. W. Tutt ... ... 49 RoQtgen Rays — Edward P. Thompson ... ... 142 Story of the Chemical Elements, The — M. M. Pattison Muir ... ... ... ... 141 Story of the Earth's Atmosphere, The — Douglas Archibald ... ... ... ... ... 215 Story of the Mine— Charles Howard Shinn ... 238 Story of the Weather, The— G. F. Chambers ... 141 Structural Botany — Dunkinfield Henry Scott ... 70 Studio, The, 1896 ... ... ... ... 32 Text-Book on Shades and Shadows and Perspective —John E.Hill ... ... ... ... 216 Theories of Magnetism and Electricity — Charles E. Curry ... ... ... ... ... 299 What to do in Cases of Poisoning — Murrell ... 117 Whitaker's Almanack, 1897 ... ... ... 32 Who's Who, 1897 ... ... ... ... 117 Winnipeg, Manitoba, To, and Back — Stephen Marriott ... ... ... ... ... 32 AVood Carving — Joseph Phillips ... ... 32 Botanical Microtechnique— By Dr. A. Zimmermann, Keview of ... ... 297 Browne, W. Lyon, Jun. — Letter on the Language of Shakespeare's Greenwood ... ... ... ... ... 213 Bulman, G. W.— Letter on Bacillus in Coal 50 Busbridge, A. W.— Letter on " Lather" and " Dilhng" 167 Calendar, The Indian— By R. Sewell and Sankara B. DIksit, Review of ... ... ... ... ... 48 Cambridge Natural History- Volume II., M'cniis, Rotifers, and Polyzoa, Review of 140 Cat, The Pedigree of the— By R. Lydekker ... ... ... ... 181 Chemical Solubilities, Inorganic, A Dictionary of- By A. M. CoMEY, Eeview of 30 KNOWLEDGE Chemical Students, Notes for — By Dr. Petek T. Austex, Review of Chemistry and the Chemical Arts, On the Progress of, during the Queen's Reign — By Prof. T. E. Thorpe Chemistry, Elements of — By RuFus P. WiLLiAjrs, Review of Chemistry, Experimental — By J. Castell-Evvxs, Review of Chess Column — By C. D. LococK 23, 55, 79, 103, 127, 175, 199, 223, 217, 271 City, A, in the Form of One Huge House — Note on Gierke, Agnes M. — Sixty Years of Astronomical Research Calcium in the Sun Clouds, The Decay of— By Dr. J. G. McPherso.v Cock Lane and Common Sense — By Andrew Laxg, Review of .. Cold, Coming — By Ales. B. MacDowall Cole, Prof. Grenyille A. J., M.R.I.A., F.G.S — Sixty Years of Geological Research ... The Edge of a Continent The Heart of a Continent Comets. Periodical, due in 1897 — ByW. T. Lynx "Commandments, The Ten" — Letter on ; by Silvanis P. Thompson Continent, The Edge of a— By Grenyille A. J. Cole Continent, The Heart of a — By Grenyille A. J. Cole Corona, An Old Record of the — By E. W. Maunder CroU, James, Autobiographical Sketch of — By James Campbell Irons, Review of Crolls, Dr., Theory of Glaciation — Letters on ; by W. H. S. Monck ... 138, Letter on ; by Jas. D. Hardy Crookes. Sir Wm., on Diamond Mining — Note on Cuckoo, Curyes of the — Letter on ; by Alex. B. MacDowall Currents, Alternating, and Alternating Current Machinery — By Profs. D. C. Jackson and J. P. Jackson', Review of Darwin, Charles, and the Theory of Natural Selection — By E. B. Poulton, Review of Darwin, Unyeiling of Statue of, in Shrewsbury^ Note on Davy Faraday Research Laboratory — Note on 69 85 278 31 151, , 303 292 34 232 18 28 241 112 208 282 55 189 208 282 ' 9 101 187 166 14 1G6 168 116 213 13 Davy, Humphry, Poet and Philosopher— By T. E. Thorpe, Review of 26 Denning, W. F., F.R.A.S.— The Approaching Shower of Leonids . . 249 Diamond, The Genesis and Matrix of the — By H. C. Le\vis, Review of 192 Dog, On the Pedigree of the— By R. Lydekker . . ... . 244 Dogs, A History and Description of the Modern, of Great Britain and Ireland — By PiA-n-DON B. Lee, Review of 280 Dragon Fly, The Metamorphosis of a— By Rev. A. East 195 Duncan, Francis M. — Letters on the Leaf-Cutter Bee ... 51,99 Dwellings, Healthy — By Sir Douglas GAiTON, Review of 116 Earth, Measurement of the — By A. Fowler ... .. 148 Earthquake, The Recent— By J. Logan Lobley ... ... ... ... 1 East, Rev. A. — The Metamorphosis of a Dragon Fly 195 Artificial Simspots . ... ... 288 Eclipse, The Total Solar, of 1898 286 Editorial . . . ... .. 281 Egg Collecting in its Relation to Science— By Leopold Field ... .. .. 266 Electro-Chemistry, Elements of— By Dr. RoBEBT LiiPKE, Review of ... ... 237 Electro-Physiology — By W. Biedermann, Review of 168 Elger, Thomas Gwyn Empey— Obituary Notice of ... ... 68 Enock, Fred, F.L.S., FES.— On Describing and Drawing Insects . . ... 5 Letters on the Leaf-Cutter Bee ... 13, 72 Life History of the Common Tiger Beetle ... 73 The Insects of a London Back-Garden 105, 153 Fairy Flies 202 The British Trap-door Spider— I., II. 250, 300 Era, The Dawn of a Brilliant — By John Mills ... ... 2 Era, The Threshold of a New 158 Ethics and Social Philosophy, A School of — Note on 293 Ethnology — Annual Reports of the Bureau of, to the Secre- tary of the Smithsonian Institution, Review of 276 Evolution, Pioneers of— From Tholes to HiLvley, by E. ClodD; Review of '.. ... 116 Field, Leopold. F.R.S.E.— Egg Collecting in its Relation to Science ... 266 VI. KNOWLEDGE. Fishes, Marine Food, Life Histories of the British — By W. C. McIntosh and A. T. Mastekmax, Review of 279 Latter on ; by A. T. Masterman ... .. 291 Fishes, Marine, of the British Islands — The Nutuml History of the MarhetaoU', by J. T. Cunningham, Eeview of ... •■■ 115 Fishing Grounds, A Survey of — Note on 46 Flammarion, Camille, F.R.A.S. — Some New Views as to the Planet Venus — I., II. 281,258 Flanery, David — Letters on Variable Stars ...72,139,236 Flies, Fairy — ByF. Enock 202 Flight, Wind as an Aid to— By F. Y>\ HE.u.LEy 188 Letter on ; by J. H. S. MoxLEY 210 Fowler, A., F.R.A.S.— The Chemistry of the Stars 77 Letters on the Chemistry of the Stars 98, 118 The Measurement of the Earth . ... 148 Fowling, First Lessons in the Art of Wild — By Abel Chapman, Review of ... 116 French, J. — Letter on Icework, Past and Present ... 12 Gases, The, of the Atmosphere — Till' Hhiory of their Discovery, by Prof. W. Eamsay, Review of ... ... ... ... 110 Gatke, Heinrich — Obituary Notice of 68 Geography, The Victorian Era in — ByH. R. Mill 60 Geological Research, Sixty Years ot— By Grenville A. J. Cole ... ... ... 112 Geology, Elementary — By G. S. BouLGER, Review of ... ... 70 Geometry, Euclid's Elements of— By H. M. Taylor, Review of 47 Glass. Utilization of Waste — Note on .. ... 109 Gold Extraction by the Wet Process — Note on 92 Gold Production, The World's— Note on 298 Gold under the Streets and Houses — Note on 263 Grahame, A. G. Moncreiff — Letter on the Mystie Number Three . . . 292 Grasses, The True — By Ed^v.^rd Hackel, Review of ... ... 278 Habit and Instinct — By C. Llovd Morg.^n, Review of ... ... 69 Hardy, Jas. D. — Letter on " The " Glacial Period ... 160 Haunt, A Well-Loved— By Harry F. WiTHERBY 130 | Headley, F. W., M.A.— Animal Life in Arctic Regions Wind as an Aid to Flight Helium and Argon as Minerals — Note on 21 183 293 Hemsley, W. Botting, F.R.S., F.L.S.— On the Vegetation and Some of the Vegetable Productions of Australasia 66, 118, 161, 242 Hill, G. F., M.A.— English Medals 82,184 Hill, G. Harcourt — Letter on thie Mystic Number Three . . . 292 Hudson, C. T., F.R.S — Letter on Sunspots .. ... 72 Hume, W. F., D.Sc— Nansen's Waymarka to the North Pole ... 33 Hygiene for Beginners— By E. S. Reynolds, Review of ... 215 Hypnotism and its Application to Practical Medicine — By ( )tto Georg Wetterstraxi), Review of . . . 275 Icework, Past and Present — Letter on ; by J. French ... ... ... 12 In Russet Mantle Clad — By George Moeley, Review of ... 297 Insects, On Describing and Drawing— By F. Enock 5 Insects, The, of a London Back Garden— By F. Enock 105,163 Jackson, E. H. — Letter on Lunar Rainbows ... ... ... 50 Jervis, Lionel — Pit-Vipers 206 Letters on More about Antivenene ... 237, 261 Jubilee Honours 158 Kinetography : the Production of " Living Pictures "' — By H. Snowden Ward 216 Klondike, Auriferous Deposits of Note on ... 213 Laboratory, A National Physical — Note on 214 Laboratory, The New State- By John Mills 268 Land and Sea, Twixt — By Harry F. Witherby . . . . ... 43 " Lather " and " Dilling "— Letter on ; by A. W. Busbridge ... ... 167 Lavalette, G. E., B.Sc — Letter on a National Astronomical Museum 188 Lead as a Reflecting Surface of Mirrors — Note on 291 Leaves, The Ministry of — By Rev. Alex. S. Wilson 197 Lemon, M. L. — Letter on the International Congress on the Protection of Birds... ... 292 Lens, Pocket, Through a— By Henry Scherren, Review of ... .. 288 KNOWLEDGE Vll. Leonids, The Approaching Shower of — By W. F. Denning 249 Life in Early Britain— By Bertram C. A. Windle, Keview of 275 Life, The Dynamics of — By Sir Willi A5I Go\\'EK, Review of ... ... 230 Literature, On the Study and Use of Scientific — By R. Lydekkeh ... ... 273 Lloyd, W. F.— Letter on the Sexual Sense and the X Eaya 12 Lobley, Prof. J. Logan, F.G.S.— The Recent Earthquake . ... ... 1 The Age of Mountains— I., II., III. 15, 92, 136 Locock, C. D., B.&.Oxon. — Chess Column 23, 55, 79, 103, 127, 151, 175, 199, 223, 247, 271, 303 Lydekker, R., B.A.Cantab., F.R.S.— The Origin of Some Domestic Animals ... 63 Biological Progress in the Victorian Era 110 An Invisible Monkey ... ... ... ... 129 The Pedigree of the Cat 181 The Pedigree of the Dog 244 EngHsh Plains and Escarpments ... ... 263 The Study and Use of Scientific Literature 278 The Beaver in Norway ... ... ... 295 Lynn, W. T., B.A., F.R.A.S.— Periodical Comets due in 1897 ... . 55 MacDowall, Alex. B., M.A.— Letter on Curves of the Cuckoo ... ... 166 Coming Cold 241 Mammals, A Geographical History of — By R. LvDEKKER, Review of ... ... ... 97 Maple Mould, The— By Rev. Alex. S. Wilson ... ... .. 89 Markwick, Lt.-Col. E. E., F.R.A.S.— The Zodiacal Light 51 Mars, The Hourglass Sea on — By E. M. Antoniadi .. 169 Masterman, A. T. — Letter on the Life Histories of the British Marine Food Fishes 291 Mathematics, Higher — By Profs. Mansfield Merkim.\n and R. S. Woodward, Review of ... ... .. 192 Matthews, Rev. Andrew- Obituary Notice of 295 Maunder, E. Walter, F.R.A.S.— An Old Record of the Corona ... ... 9 The Nebula round ?; Argus .. ... ... 120 Aristarchus and the Sinus Iridum ... ... 142 Letter on a National Astronomical Museum 189 Note on Sundials ... ... 189 Note on Biela's Comet ... 263 McPherson, Dr. J. G., F.R.S.E.— The Decay of Clouds 18 Can the Deaf appreciate Music ? ... 185 More about Antiveneue ... ... 205 Mechanical Science during the Queen's Reign, Progress in — By R. G. Blaine .. 132 Medals, English — ByG. F.Hill 82, 184 Mercury Surface, Ripples on- Note on Metals- 92 By A. K. Huntington and W. G. McMillan, Review of ... . . ... ... ... 192 Meteoric Stone, Heaviest, on Record — Note on 263 Metre and the Inch, The — Letter on ; by T. Wilson 268 Milk : its Nature and Composition — By C. M. AiKMAN, Review of 31 Mill, Hugh Robert, D.Sc, F.R.S.E.— The Victorian Era in Geography ... ... 60 Mill, John Stuart, Early Essays by- Review of ... ... ... ... ... 183 Mills, John, F.R A.S.— The Dawn of a Brilliant Era ... ... ... 2 A Pantheon of Science ... ... 41 The New State Laboratory 268 Mira Ceti — Letter on : by W. E. Besley 100 Mirror, A Gigantic — Note on .. . . 240 Miscellaneous Papers — By Prof. H. Hertz, Review of 96 Mollusca of the British Isles— A Moiiiif/niph of the Laml ami Freshwater, By .J. W. Taylor, Review of . . 96 Monck, W. H. S.— Letter on Underground Cavities and Streams in Ireland ... ... ... ... ... 49 Letters on Star Systems ... 72, 117, 165, 187 Letters on Dr. Croll's Theory of Glaciation 138, 187 Monkey, An InYisible — By R. Lydekker Monuments, The Land of the — By J. PoLL.ARD, Review of Moon, A Great Photographic Atlas of the Note on Moon, Photograph of the 129 48 213 261 Morley, George — The Superstitions of Shakespeare's Green- wood 122 The Language of Shakespeare's Greenwood 146, 172, 265 Mosses, British, The Student's Handbook of — By H. N. Dixon, Review of 28 Motor Car, Cost of Travelling by — Note on Mountains, The Age of— I., II., III.— By J. Logan Lobley ... ... 298 15, 92, 136 Vlll. KNOWLEDGE Moxley, J. H. S.— Letter on Wind as an Aid to Flight ... 210 Music, Can the Deaf appreciate ? — By Dr. J. G. McPhekson ... 135 Letter on ; by W. Alfred Pakr ... ... 167 Mystic Number Three, The 252 Mystic Number Three, The— Letter on ; by A. G. Moncreiff Grahame . 292 Letter on ; by G. Harcodkt Hill ... ... 292 Nansen's Waymarks to the North Pole^ ByW. F.Hume 33 Nansen's. Fridtjof, "Farthest North"— Keview of ; by Haery F. Witherby . ... 57 Natural History, The Royal — Edited by R. Lydekker, Eeview of ... ... 31 Natural Selection the Creator of Species, Is ? — By Duncan Graham, Review of ... ... 116 " Nautilus " Protected and Unprotected Warships ... 19 Nautilus, Pearly, Eggs of— Note on 68 Navigation and Nautical Astronomy — By F. C. Stebbing, Review of ... ... 48 Nebula, Great, in Orion, Photograph of the— By Is.^AC Roberts ... . . ... . . 100 Nebula, Herschel Y 14 Cygni, Photograph of the — By Isaac Roberts ... , . ... ... 218 Nebula Round ri Argus — By E. W. Maunder 120 •' Nitragin "— By C. F. Town SEND 201 Norwray, New Ground in— By E. J. Goodman, Review of ... 47 Norway, Wild — By Ai;el Chapman, Review of .. 278 Observatories, Reports of 11 Ord, W. E.. B.A.— Modern Alchemy ... ... .. .. 285 Ornithological Notes, British— jilbatross in Gimbridgeslurc — E. A. Butlor ... 240 Albatross, The, in tlie North Atlantic — T. Southwell 2.57 " Arti>t, Save me from my "^T. Southwell ... 239 Aquatic Warbler in Sussex and Hampshire — J. Pratt .. ... ... ... 290 Auk, Great, Discovery of Bones of, in County Water- ford — R. J. Ussher ... ... ..." .. 240 Barred Warbler, G-reenshanks and, in Norfolk — H. ir. Slater ... ... ... .. 240 Barred Warbler in Norfolk {correction) ... ... 257 Blackbirds. A Prolific Pair of— A. G. Butler ... 257 Blackbird and Song Tlirush, Unusual Nesting Site of — K. J. Kitchen ... ... .. ... 290 Black-winged Stilt in Somerset — S. Lenis ... 291 Caspian Tern on the Trent— P. B. Whitlock ... 257 Cuckoo and Hedge Span-ow-P. W. Headley ... 256 Curlew Sandpiper, The Eggs of the— H. L. Popham 290 Duck, Ferruginous, in Deron- W. B. Tegctmeier ... 291 Falcon, Red-footed, in Aberdeenshire — G.Sim ... 2.57 Ferruginous Duck in Devon— W. B. Tegetmeier ... 291 Godwits, Notes on the— E. A. S. Elliot ... ... 2.57 Great Auk, Discovery of Bones of, in County Water- ford — R. J. Ussher ... Green Sandpiper, Possible Breeding of, in Brecon- shire-E. C. Phillips Greenshanks and Barred Warbler in Norfolk — H. H. Slater Guillemot, Herring Gulls .and ... ... 239, Gulls, Herring, and Guillemot ... ... 239, Han'ier, Montagu's, in Ireland — J. H. Teesdale Hedge Sparrow, Cuckoo and — F. W. Ileadlev Heron, Night, on the Exe— W. S. M. D' Urban , Herons catching Trout— J. J. Armistead... Herons, Food of — W. .J. Clarke ... Herring Gulls and Guillemot Kestrel, Lesser, in Aberdeenshire — E. Lee Kites in Wales^-W. W. Fowler ... Lesser Kestrel in .Aberdeenshii'e — E. Lee Marsh Tits and Honeysuckle — C. A. Witchell Meadow Pipit, Isabelline Variety of — ^W. S. M. D'Urban ... Melodious Warbler in Sussex — H. Saunders Montagu's Harrier in Ireland — J. H. Teesdale Night Heron on the Exe— W. S. M. D'Urban Nightingale's Nest, Strange Site for — J. H. AUchin Noddy Tern in Cheshire — F. Congreve ... Pectoral Sandpi])er, Occui-rence of, in Holderness — J. Cordeaux ... Pipit, Meadow, Isabelline Variety of — W. S. M. D'Urban ... Red-footed Falcon in Aberdeenshire— G. Sim Sandpiper, Curlew, Eggs of — H. L. Popham Sandpiper, Green, Possible Breeding of, in Brecon- shire— E. C. Phillips Sandpiper, Pectoral, Occurrence of, in Holderness — .1. Cordeaux Song, Autumn, of Birds — O. V. Apliu Song Thrush and Blackbird, Unusual Nesting Site of — E. J. Kitchen ... Song Thrush, Late Nesting of — G. Harding Sparrow, Hedge, and Cuckoo — F. W. Headley Stilt, Black-winged, in Somerset — S. Lewis Stork, White, at Horsham, Sussex — C. J. Marten ... Swallow, Nesting of — W. Dunn Tern, Caspian, on the Trent — F. B. Whitlock Tern, Noddy, in Cheshire — F. Congreve ... Thrush, Song, and Blackbird, Unusual Nesting Site of — E. J. Kitchen ... Thrush, Song, Late Nesting of — G. Harding Tits, Marsh, and Honeysuckle— C. A. Witchell ... Warbler, Aquatic, in Sussex and Hampshire — J.Pratt ... Warbler, Barred, and Greenshanks, in Norfolk — H. H. Slater Warbler, Barred, in Norfolk {correction) Warbler, Melodious, in Sussex — H. Saunders White Stork at Horsham, Sussex— C. J. Marten Oysters, Carrying of Disease by — Note on Parr, W. Alfred- Letter on Can the Deaf appreciate Music ? . . . Letter on the Berlin Urania Sternwarte Petrel, Frigate- Note on Photograph, Why do you? — By T. A. Ger.ald Strickland Photographic Record Association, The National- Note on 240 239 240 257, 290 257, 290 257 256 257 239 257 239,257, 290 291 256 291 290 256 257 257 2,57 290 291 290 256 257 290 239 290 240 290 290 256 291 240 291 257 291 290 290 290 290 240 257 2.57 240 47 167 211 92 124 187 Photography, Astronomical — By F. L. 0. Wadsworth Photography, Colour — Note on Photography in Illustration — By H. Snowden Ward 198, 218 67 253 KNOWLEDGE IX. Photography in Natural Colours— By H. Sno^\t>ex Wakd Physical Science, Short Studies in — By Vaui;hax Corxish, Review of Physics for Students of Medicine — By A. D.vNiELL, Eeview of Physiography for Beginners— By A. T. SiMiioxs, Eeview of Physiology, Elementary Practical, and Histology— By M. Foster and J. N. Langley, Review of Plains and Escarpments, English — By E. Lydekker Plants and Ferns, Flowering— A Manual anJ Dktionary of the, by J. C. Willis, Review of . . . Plants, Diseases of, induced by Cryptogamic Parasites — By Dr. Karl Freiherr vox Tubeuf, Review of Plants, Effects of Light on the Colour of— Note on Plants, Pitcher, Insect Digesting Powers of — Note on Ponds and Streams, Life in — By W. FuRXEAux, Eeview of ... Prehistoric Man and Beast — By Eev. H. N. Hutchinson, Review of Pritchard, Charles, The Life and Work of — Eeview of Proctor, Harry — Obituary Notice of Queen's Reign, The Science of the— I. The Dawn of a BrUliant Era. By John Mills n. Sixty Years of Astronomical Research. By Agxes M. Clerke III. The Victorian Era in Geography. By H. E. Mill IV. On the Progress of Chemistry and the Chemical Arts. By Prof. T. E. Thorpe V. Biological Progress in the Victorian Era. By R. Lydekker VI. Sixty Years of Geological Research. By Gren\tlle A. J. Cole .. VII. Progress in Mechanical Science. By E. Gordon Bl-uxe .. VIII. The Threshold of a New Era Rainbows, Lunar — Letter on ; by E. H. .Jackson Rainfall, 1895, British- Compiled by G. J. Symons and H. Sowerby Walter, Eeview of ... Rain, River, and Evaporation Observations made in New South Wales during 1894, Results of— By H. C. Russell, Review of Rain, River, and Evaporation Observations made in New South Wales during 1895, Results of — By H. C. Russell, Eeview of PAGE I 177 215 30 192 70 263 278 298 92 240 70 27 95 68 2 3i 60 85 110 112 132 158 50 214 48 Rawlings, Gertrude Burford— Letter on Runes and Oghams ... ... 13 Reliquary, The, and Illustrated Archaeologist- Vol. IL, Review of 29 Rheumatism : its Nature, its Pathology, and its Successful Treatment— By T. J. M-iCL.iGAx, Review of 69 Roberts, Isaac, D.Sc, F.R.S.— Evidence of the Evolution of Stellar Systems 10, 53 Photograph of the Great Nebula in Orion ... 100 Photograph of the Nebula Herschel V 14 218 13 144 212 Cygni Runes and Oghams- Letter on ; by G. B. Ra^-lings Ryves, P. M.— Day Views of Venus Letter on Venus Sadler, Herbert, F.R.A.S.— The Face of the Sky 22, 55, 78, 103, 127, 151, 174, 199, 223, 247, 271, 303 Science, A Pantheon of— By John Mills ... 41 Science Notes 13, 46. 67, 91, 109, 167, 187, 213, 240, 258, 263, 292 Seed, The Flight of a— By Eev. Alex. S. Wilson 254 Shakespeare's Greenwood— The Superstitions of, by George Morley ... 122 The Language of, by George Morley 146, 172, 265 Letter on the Language of, by Edwabd Snel- grove Letter on the Language of, by W. Lyon Browne, Jun. Shells, The Collector's Manual of British Land and Freshwater — By L. E. Ad.uis, Review of Simmonds, Peter Lund — Obituary Notice of Sky, A Study of the— By H. A. Howe, Eeview of Sky, The Face of the— By Herbert Sadler 212 213 96 295 141 2l£ 22, 55, 78, 103, 127, 151, 174, 199, 223, 247, 271, 303 Smithsonian Institution, Reports of the— Eeview of Snelgrove, Edward- Letter on the Language of Shakespeare's Greenwood ... South Pole, Belgian Expedition to the— Note on Sparrows, Havoc wrought by — Note on Spectrum Top, The— By T.L.Alger Spider, The British Trap-door— I., II.— By Fred. Enock .. Star Atlas — By WiNSLow Upton, Eeview of 274 212 214 214 250, 300 141 KNOWLEDGE. Star Constants, Tables for facilitating Com putation of — Review of Star Systems — Letters on ; by T. W. Backhouse Letters on ; by W. H. S. Monck Stars, The Chemistry of— By A. Fo^vLER ... Letters on ; by A. Fowler ... Stars, Yariable— Letters on ; by David Flanerv 298 ... 61,99,164 72,117,165,187 77 98,118 .72, 139, 236 Stellar Systems, Evidence of the Evolution of— By Is.\ac Roberts ... ... ... 10,58 Stone, Edward James- Obituary Notice of 140 Strickland, T. A. Gerald, F.E.S.— Why do you Photograph ? 124 Suicides. Analysis of — Note on .. ... ... .. ... 68 Sun, Calcium in the — By Agnes M. Clerke 232 Sundials — Note on ; by E. Walter Maunder ... ... 189 Sun spots — Letter on ; by C. T. Hudson 72 Sunspots, Artificial — By the Rev. A. East 288 Superstitions, Chinese- Note on 258 Survival, The, of the Unlike— By L. H. B.\iLEY, Review of ... ... ... 116 Swift's Night Flight, The— By C. A. WiTCHELL 145 Telegraphy, Wireless- Note on 258 Telescripter, The — Note on 294 Terrestrial and Astronomical Objects and Phenomena, Diagrams of — By R. A. Gregory, Review of ... ... 31 Thompson, Prof. Silvanus P. — Letter on " The Ten Commandments " ... 139 Thomson, Joseph, African Explorer — By J. B. Thomson, Review of ... ... 29 Thorpe, Prof. T. E., LL.D., F.R.S.— On the Progress of Chemistry and the Chemical Arts during the Queen's Reign ... 85 Thrush, Song, Shakespeare imitates Note of — Note on 240 Townsend, C. F., F.C.S.— "Nitragin" 201 Underground Cavities and Streams in Ireland — Letter on; by W. H. S. Monck 49 United States National Museum, Report of the — Review of ... ... ... ... ... 274 Urania Sternwarte, Berlin — Letter on ; by W. Alfred Paer ... ... 211 Yase, Greek, Painting in Italy — l!y U. B. \V.\LTERs 226 Vatican, Borgia Apartments in the — Note on 109 PAGE Yenus — Letter on ; by P. M. RyvEs 212 Yenus, Day Yiews of — By P. M. Ey^^es 144 Yenus, Some New Yiews as to the Planet— I., II. — By Cajiille Flammarion ... 234,258 Yertebrate Skeleton, The— By S. H. Reynolds, Review of ... .. 298 Yipers, Pit By Lionel Jer\is ... ... ... 206 Volcanoes of Great Britain, Ancient — By Sir Archibald Geikie, Review of ... 179 Volcanoes of North America — By Israel 0. Russell, Review of ... ... 280 Wadsworth, F. L. 0.— Astronomical Photography ... ... 193,218 Walters, H. B., M.A., F.S.A.— Greek Vase Painting in Italy . 226 Ward, H. Snowden, F.R.P.S.— Photography in Natural Colours 177 Kinetography : the Production of " Living Pictures" 216 Photography in Illustration . . ... 253 Warships, Protected and Unprotected — By " Nautilus " ... ... ... 19 Water Supply — By Prof. W. P. Mason, Review of 47 Waterspout seen near Cromer — Note on 240 Whitteron, F.— Letter on Vegetation of Australasia ... 212 Wilson, Rev. Alex. S., M.A., B.Sc— The Maple Mould 89 The Ministry of Leaves 197 The Flight of a Seed ... 254 Wilson, T.— Letter on the Metre and the Inch 268 Witchell, C. A.— Bird-Songs in Winter ... ... 17 Bird- Songs in Spring ... 81 The Swift's Night Flight 145 Bird- Songs in Summer . ... ... 157 Bird-Songs in Autumn ... ... ... 225 Letter on 262 Witherby, Harry F., F.Z.S., M.B.O.U.— Twixt Land and Sea Fridtjof Nansen's " Farthest North," Review of A Well-loved Haunt The Birds of Oban's Isles X Rays, The Sexual Sense and the— Letter on ; by W. F. Lloyd Year, Round the — By Prof. L. C. MiALL, Review of Zodiacal Light, The— By Lieut. -Col. E. E. Markwiok Zoology, International Congress of— Note on Zoology, Text-Book of— By Dr. J. E. V. Boas, Review of 43 57 180 221 12 69 51 294 30 KNOWLEDGE XI. INDEX OF THE PRINCIPAL ILLUSTRATIONS. PAGE Illnstrions Philosophers of a Bygone Era y.ntispiece (Banks, Dalton. Davv, Faraday, Herschel, Hunter, .Jecner, Watt, Wollaston.) Adams, Prof. J. C 39 Africa — Maps of, in 1837 and 1897 (Plate) 82 Airy, Sir George 37 Alcoholic Liquids— StiB, used in distiUing 270 AUuYlal Accumulation- Landscape in tlie Plain of the Danube, sho-n-ing ... •■• 284 Alternator at Niagara, 5000 H.P. (during construction) 13* Anodonta cygnea 96 Aristarchus and the Sinus Iridum (Plate) 1J3 Key map to Plate 143 Aspen (Popvlus tremula) — Felled by tl\e Beaver (Aamin ... 297 Australasia, Yegetation and Vege- table Products of — Glory Pea, CHanthvs Bampieri Marginatus {P\&te) fi6 Eucali/ptus globulus, A Flower of 119 Eucalyptus globulus, A Flower of, after Leaves are thrown off ... 119 Eucalyptus macrocarpa, A Flower of 119 Blue Grum, Seed-vessel or Fruit of the 162 Eucalyptus amygdalina. Cluster of Seed-vessels of ... ... ... 162 Eucalyptus cornuta. Cluster of Seed-vessels of ... ... ... 162 Eucalyptus calophylla, A single Seed-vessel of ... ... .- 163 Eucalyptus ptychocarpa, A single Seed-vessel of 163 Eucalyptus pyriformis, A Seed- vessel of ... ... . . ■•• 163 Eucalyptus Lehmanni, Cluster of Seed-vessels of ... ... .- 163 Eucaliiptus tetraptera. Seed-vessel of.: 164 BanTcsia, A Cone of a Species of ... 242 Saiea crassifolia, Open Seed- vessel of ... .■- ... --. 243 Hakea crassifolia. Seed from the Seed-vessel of ... ... ... 243 Grevillea qihhosa. Seed-vessel or Fruit of' 243 Pear. Australian Wooden, Seed- vessel or Fruit of . . . . 244 Pear, Wooden, A Seed of the ... 244 Basalt- Ejected Block of, which has fallen among Carboniferous Shales and Limestones ... ... .. 1*^" Bear, Polar, charging 41 Bears, Polar, at Play i Plate) ... 40 Beavers, Young 296 Bee- Foreleg of, with Tibial Comb ... 69 PAGB to the 1.5 Beetle, The Tiger- Larva Larva " on the watch " Larva : Act of seizing ita Prey Pupa Just evolved from Pupa ... Excavating and ascending Surface ... Boa Constrictor— TheSkuUof Butter — Apparatus for determining Eefractive Index of Cailletet's Apparatus for Liquefying Oxygen Cod- Egg and Embryo of (eight figures) Cold- Coming, Curves of Cones, Yolcanic Coral Growth, Stag's Horn- Great Barrier Reef, Queensland ... Corona, Drawings of the— Miss Kate Wolcott's Drawing ... Trouvelot's Di-awing Assyrian " Ring with Wings" ... The " Presence " on ALSsyrian Monuments Egyptian " Winged Disc " Croll, James, LL.D.. F.R.S Cuckoo — Curves of the Darwin, Charles — Portrait of (Plate) ■ ... Statue of Dragon Fly, Metamorphosis of the— Larva of the : Mask extended Larva of the Emergence of the Body (three figures) ... Emerged and hanging on the Nymph Skin (three figures) ... Duck, Nest of the Wild Duck, Wild, flying from the Land ... Eclipse — Shadow Track of the Solar (.January, 1898)... Equatorial Common in 1837 — A Form of ... I Eyepiece End of the 36-inch Equa- 1 torial of the Lick Observatory ... Faraday, Michael- Statue of. at Royal Institution ... i Fjords, Typical— Coastline in South-West of Scot- 1 land ... ; Flies, Fairy (Plate) I Flow Structure in Felsite Geological Sections — Across the JIalvems Across the Longmynds, Shropshire Through Snowdon Through Mount St. Gothard Through Mont Blanc Ghost-Dance, The 74 75 75 76 76 30 269 279 241 16 190 9 9 9 10 10 101 166 110 168 196 196 196 197 222 44 PAOB 130 221 287 39 38 42 209 202 180 93 93 94 137 137 276 277 6 Gnereza, The Gull, Nest of the Common Hahaiwiiqti, Natacka, and Soyok^ mana (Medicine Men) Hare— The Wounded 46 Herschel, Sir John 36 Insects, Drawings of — Part of Upper Wing of a minute Hymenopteron ... Photo-miorograph of Upper Wing of a minute Hymenopteron, from Nature ... ... •■. 7 Photo-micrograph of Tongue of Bee " Tongue of Bee in its natural form 7 Insects of a London Back-Garden — Empty Pupa Case and Wasp Fly 106 Willow Saw-Fly 106 Saws of A'ematus gallicola ... 106 Section through Willow Gall, with Larva of Saw-Fly ... ... 106 Parasite of WlUow" Saw-Fly ... 107 Parasite of WiUow .Saw-Flvpiercing GaU " 107 Section of GaU, showing paralyzed Larva and Egg of Parasite ... 108 Section of Gull, showing paralyzed Larva and Egg and Larva of Parasite 108 Section of Gall, showing Skin of Lai-va and Pupa of Parasite ... 108 Eulophus nemati (Female), Parasite of WUlow Saw-Fly 109 Eulophus nemati (Male), Parasite of Willow Saw-Fly 109 Twig of Black Currant in April ... 153 Black Currant Gall Mit€ 153 Twigs of Black Currant, showing . GaUs 154 Section of G^U, showing Predaceous Larva ... ■■. 154 Destroyer of GaU Mite 154 Devil's Coach-Horse Beetle taking a Meal 154 Devil's Coach-Horse Beetle ... 155 Mouth Organs of Devil's Coach- Horse Beetle 155 Earwig : wings closed ... ... 155 Earwig: wings expanded ... ... 155 Earwig: wings half closed .. 156 Earwig ; wings three-quarters closed 156 Isles- Some of the (of Oban) 223 " Laughing Jackass," North Queens- land 191 Leptoplana in the act of swimming 140 Limestone — Fold in, illustrating formation of Continental Edge LocomotiYe Engine — Forerunner of the Modern ... 4 Ly ell. Sir Charles, F.R.S 113 Maple Mould, Thi 89,90 209 xu. KNOWLEDGE. Mars— The Hourglass Sea on (Plate) ... Drawings of the Hourglass Sea on, by — Huyghens, De la Rue, Secchi, Lockyer Kaiser, Grledhill, Franzenau, Scliiaparelli, Terby Map, showing the theatre of the changes in Hourglass Sea of ... Medals — Kendal, John Mercator, Michael... Charles I., by Briot Enghsh Medals (Plate) Gold Medal presented to Dr. Nansen by the Royal Geographical Society Dayison's Nile Medal Reverse of Pistrxieci's Waterloo Medal Englisli Medals since 1660 (Plate) Megachile centuncularis, Cell of ... Meridian Column, The, at Hammerfest Moon, Tlie (Plate) Mule-Deer, Head of a Male Hansen's " Farthest North "— Observation with Sextant and Arti- ficial Horizon, July, 1895 • Movable Meteorological Station on the Ice, July, 1895 Deep-water Temperature Medal of the Eoyal Geographical Society Nebula round ij Argus (Plate) Olivine-Basalt— Section of ... Pneumatic Experiment at the Royal Institution (after Gillray) Reindeer — The Sentinel PAaE 170 170 171 173 83 83 84. 81 91 185 186 186 99 149 261 97 I 57 I 58 59 91 120 114 26 Isaac, Photographic Roberts, Dr. Plates by- Star Regions in the Constellations -Auriga, -Argo, and Cassiopojia ... Spiral Nebid(o Orion, The Great Nebula in Nebula Herschel V 14 Cygni Roman Bath at Bath- Interior of the ... Schwarzhorn— PASS Slope of the 10 54 100 218 275 283 Seed- The Flying figures) Apparatus of (five 255, 256 45 233 278 Snipe feeding in a Creek on the Snow- covered Saltings Spectra, Spark — Sliowing Effect of Density on the Lines of Calcium Spectra, Stellar- Photographed at South Kensing- ton (Plate) 78 Spider, the British Trap-door — Section of the Nest of 251 Photograph of the Male ... .'.' 251 Photograph of the Female ... 251 Jaws of Common Garden Spider... 252 I Jaws of British Trap-door Spider 252 I Mechanism of the Jaw of, showing Fang and Poison Bag ... ... 300 Large and small Spinnerets of ... 301 Blowfly on the Silken Tube of ... 301 Blowfly seized by ... ... 301 Dragging the Blowfly through Rent in Silken Tube 302 Retiring with its Prey ... ,_[ 302 Spiderlings departing, The ..." 302 Stork, Marabou — In the Zoological Gardens 126 Stream running from under the Rock near Castlebar 50 Sulphur in Steel — Estimation of ... _ 269 Sunspots, Artificial (Plate) 288 Thornton Abbey, The Gate House of 29 Toblach and the Yalley of the Rienz in Tyrol Torpedo-Boat with Guard opened— Model of Triangulation near the River Danube Vase, Greek, Painting in Italy— Bell-shaped Krater (Mixing Bowl), with scene from a farce Krater (Mixing Bowl), for use 'in funeral ceremonies, with scene representing two mom-ners bring- mg offerings to the tomb Situla (Bucket), with scene re- presenting Dionysos espousins Ariadne ^ Phiale (Saucer), painted with a figure of Ganymede Hych-ia, with painting in opaque white on black background Lekythos (Oil Flask), ornamented w-ith figures in relief Yedalia cardinalis— Imported Ladybird, Enemy of the White Scale ... ... Yenus In 1897 (Plate) Yenns — Cassini's 1666-7 Further Sketches of, by Cassini ..'. Illustrations of, by Bianchini ..'. A Sketch of, by S'chroeter, 1788 .'.'. A Sketch of, by Wm. Herschel Representations of, by Schiapareili A View of, by Schiapkrelli, 1895 ... The Planet as drawn by Lowell iii 1896 PASH 284 21 150 227 228 229 229 229 230 293 236 Original Sketches of, Yesnvian Cone— Efeects of Denudation in a Yienna Observatory Yulture— Young King, in Down Plumage Warrior's Courtship, The Woodcock Chicks (Plate) Zebus, Indian, in the Zoological Gardens 234 235 235 236 236 259 260 260 179 35 31 27 130 125 January 1, 1897.] KNOWLEDGE. ilUSTRATEp MAGAZINE JTERAT LONDON: JANUARY 1, 1897. CONTENTS. The Recent Earthquake. Bv Prof. J. Logan Loblkt.F.G.S. The Dawn of a Brilliant Era. By JoHX Mills, F.K.A.S. (Illustrated) Illustrious Philosophers of a Bygone Era. {Plate.) On Describing and Drawing Insects. B.v Feed. Exock, F.L.S., F.E.S. {Illustrated)... The Spectrum Top. By T. L. Algek, LL.D., Ph.D. An Old Record of the Corona. By E. "Walter llArNDEB, F.R.A.S. {Illustrated) Evidence of the Evolution of Stellar Systems. By Isaac BoBEBTS, D.Sc, F.E.S. {Plate) Reports of Observatories Letters : — GEETErDE Buefobd Eawlujos ; J. FEENcn ; W. F. Llotd ; Feed. Exock Literary Supplement — Que Book Table Eetiews of Booes. {Ulastrated) .. Shoet Notices ... ... ... ... Science Notes Books Received „ The Age of Mountains.— I. By Prof. J. Logan Loblet, F.G.S. {Illu.ifraied) Bird-Songs in Winter. By Chaelks A. Witchell The Decay of Clouds. By Dr. J. G. McPheesok, F.R.S.E. Protected and Unprotected Warships. By Xautilus. {Illu.ftraied) Animal Life in Arctic Regions. By F. W. Headlet, M.A. The Face of the Sky for January. By H.Sadlee, F.R.A.S. Chess Column. By C. D. Locock, B.A.Oxon. PAGE 1 10 11 12 25 26 32 13 14 1.5 17 18 19 2L 22 23 THE RECENT EARTHQUAKE. By Prof. J. Logan Lobley, F.G.S. THE British Islands have been so free, during historical times, from those violent seismic dis- turbances that have from time to time devastated other lands, that their inhabitants have very generally come to the comforting conclusion that this portion of the earth's surface enjoys an immunity from surface movements. And yet even modern history does not favour this roseate view, for, not to speak of the earthquake shock that so alarmed our ancestors two centuries ago, and others in the early part of the present century, the very recent Essex earthquake, when a spire at Colchester was thrown down and walls were fissured, sufficiently shows that this part of the world is, like all others, affected by the agencies of nature that are un- ceasingly working beneath the exterior of the globe. These agencies are very commonly all thought to be volcanic, and it is a dictum often stated as indisputable that an earthquake is an uncompleted effort of nature to establish a volcano. Such a statement, however, appears to me to be not only misleading, but even the opposite of the truth. A movement of the surface rocks of the globe may be produced by several causes, and, undoubtedly, volcanic action is one of those causes. But a volcanic earthquake takes place in volcanic regions where volcanic activity has successfully asserted itself and a volcano has been established. Thus the earthquakes of volcanic regions are consequent upon volcanic action and not the cause of it. But the causes of the earthquakes of non-volcanic regions, such as are the British Islands in this epoch, are non-volcanic, and must be consequent upon forces that are acting independently of volcanic action. The surface rocks of the globe in every region, volcanic or non-volcanic, it is obvious must be affected by those cosmic agencies that disturb the normal condition of their foundations— the underlyinir rocks. Increase and decrease of temperature, causing expansion and contraction, are such disturbing agencies ; and increase of temperature is produced by chemical action, which may be commenced, stimulated, retarded, or suppressed by decrease or increase of pressure, resulting again from meteorological or sub- terranean varying conditions. Earthquakes must con- sequently be considered to be merely the expression at the surface of deep-seated distui-bances, the normal results of normal cosmic agencies. It is, therefore, a matter almost for wonder that earth- quakes are not more frequent than they are in this and other non-volcanic regions, and their rarity here and the absence of violent or destructive shocks must be attributed to the at present favourable geological conditions of these islands. The earthquake of December 17th last affected England along the strike of the Upper Paleozoic and the Secondary rocks, the older Cambrian and Silurian areas escaping, and also the Essex Tertiary area that suffered in 1883. So far from these English earthquake shocks causing alarm or terror, or apprehension for the future stability of our country, they should have a reassuring effect, since they show that the present geological structure of our island is in accordance only with the production of non- devastating earthquake shocks. From the extensive faulting and Assuring of the older rocks we must conclude that seismic disturbances were violent and frequent in this region in Palaeozoic times ; but since that far-distant epoch surface movements have been less frequent, from which we may legitimately conclude that in the British Islands the geological conditions have become more and more favourable to that surface stability expressed by the words terra ftrma. It may be appropriate here to give briefly the conclu- sions as to the cause of earthquakes that are stated more at length in Knowledge of -July, 1895. page IGl. Earth- quakes of non-volcanic regions, which have their centres far away from any active volcanic vent, are primarily caused by chemical action when allowed by favouring local physical conditions, prominent amongst which is diminution of pressure. This chemical action, though not sufficient to produce rock-fusion, is, however, adequate to cause some. heat — with, possibly, gases and vapours — that is of necessity accompanied by local expansions and succeeding contractions, which occasion deep- seated sudden fractures, and so give rise from separate and dis- tinct dynamic foci to earth vibrations, which at the surface cause earthquakes, and earthquake shocks and tremors. KNOWLEDGE. [Janxary 1, 1897. THE |y/^|SCIENCE .|OFTHE|^ I QUEEN'S REIGN. I.-THE DAWN OF A BRILLIANT ERA. By John Miils, F.E.A.S. *' Not in V.Tin the distance beacons. Forward, forward, let ws raus:e ; Let the great world spin for ever down the ringing grooves of change." THE year upon which we have just entered completes the sixth decade of Queen Victoria's reign — a reign which for fulness of time, virtuous and enlightened policy, and glorious conquest in the arts of peace, has no parallel in the annals of this realm. Could one but draw true word-pictures of social England as it was in the year 1837, and as it is to-day, after the lapse of sixty years — years teeming with the fruits of genius in every walk of life — the contrast between the two periods would form a convincing proof of the intellectual development and the amplification of the resources of the people — advantages won by a bloodless victory of mind over matter. Yet there is in reality no gulf between the past and the present. The men whose doings have laid the foimdatiou of our commercial prosperity belong to a past age, and we who carry on the appointed work of improvement and civilization are their progeny and belong emphatically to past times. Theirs was the understanding at once penetrating and vigilant, but more distinguished, perhaps, for the caution and sureness of its march than for the brilliancy or rapidity of its movements. It is our object in this short sketch to convey some idea of the condition of science when the Queen ascended the throne in 1837. Other papers will follow dealing with the development of the several branches of science during the past sixty years. The mind of man in its progress towards its higher destiny is confronted, in the main, with the physical earth as a problem which, within the Umits of a life, it must struggle to solve. The intellectual spirit is capable of embracing all finite things. Science alone can interpret their mysterious whispers. It requires an effort of the imagination to the great bulk of people now living to realize what the condition of life must have been in 1837. Divested of the luxuries which science has heaped upon us since that auspicious epoch, we should relapse into a state of civilization which would more nearly resemble that of ancient Greece and Rome than that to which we have attained at the present time. One of the factors too important to ignore in the grand sum of scientific progress during the unique reign of our gracious sovereign lady is the Soyal Institution, which was founded in the year 1800. " Its aim and objects were to diffuse the knowledge and facilitate the general introduc- tion of useful mechanical inventions and improvements, and to teach by philosophical lectures and experiments the application of science to the useful purposes of life." Count Eumford, to his lasting credit be it said, was the chief promoter of this temple of science, which can boast of having given in its early days employment to Youug, Davy, Brande, and Faraday. This institution may, with some regard for truth, be looked upon as the nursery in which the plants that have yielded so much fruit in their maturer years were tended in their infancy. By whom ? By men who were our progenitors in science — patient, indomitable, calmly and wisely bold, modestly self-reliant, ever watching, ever toiling, ever adding to the store of knowledge that was to benefit not them alone but the great human race ; each guided by his own perceptions of what is great in humanity and fitting in a nation — men whose instinct it was to work for the world and fight against misery. About the year 1887 what has been called the " old astronomy " may be said to have culminated. The elder Herschel, almost equally famous as optician and astronomer, had, so to speak, put on the coping stones of the fabric. His magnificent speculations on the Milky Way, the constitution of nebuht, etc., first opened the way to the conception that what was called the universe was in all probability but a detached and minute portion of that fathomless series of similar formations which ought to bear the name. In a word, he assigned to the earth its true position — an ignoble one — among the vast array of worlds revolving in the depths of infinitude ; made clear to the thoughtful student of nature that the vastnesa of created worlds extends beyond the confines of imagini- tion ; that the phenomena of reality are more startling tban the phantoms of the ideal. It is true that the younger Herschel, who continued the labours of his illustrious father, made some experiments in spectrum analysis as early as the year 1835; and Niepce, in 1824, by fixing images produced by the camera obscura, invented photography ; but the part which these two branches of science were to play in the " new astronomy " was not so much as conceived at the commencement of the present reign. That the prism should be the touchstone of worhls, the markings in the spectra of celestial bodies teUmg the story of the composition of these denizens of outer space with sometbing like the precision with which a jeweller determines the quality of gold by comparing its colour with the markings of specimens of known quality on the touchstone, is a chapter in the romance of science which belongs to the Victorian era ; as is also the part played by photography in reveahng the existence of stellar and nebular systems far beyond the reach of telescopic and spectroscopic power, and its useful application to Doppler's principle as regards the speed and direction of the motion of stars. In the domain of geology, a great awakening to a true knowledge of the history of our planet had been effected in the early part of the century by the teachings of William Smitb, the "father of English geology," Agassiz, JIurchison, and others. In February, 1831, the Geological Society, which had hitherto passed him over with a sort of silent contempt, was at length roused to an impartial estimate of Smith, which resulted in the passing of a resolution — " That the first Wollaston medal be given to Mr. William Smith in consideration of his being a great original discoverer in English geology, and especially for his having been the first in this country to discover and to teach the identification of strata, and to determine their succession by means of their embedded fossils." This shrewd observer pointed out that rocks were deposited in successive order, and thus carried the doctrine of evolution into the domain of geology ; and he proved that whatever stratum was found in any part of England, the same remains would be found in it and no otber. Agassiz, about the same period, was working out his theory of glaciers, great boulder deposits, striation of rocks, and so John Dalton. 1766 1844. Sir Humphry Davy. 1778-1829. William Hyde Wollaston 1766—1828. Edward Jenner 1749—1823. Sir William Herschel. 1738—1822. Sir Joseph Banks. 1743—1820. (I'rcsiih:a,ijthc J.'mu.i! S":-:.!,, fur /■i.-ty-lm i/cars.) John Hunter. 1728—1793. James Watt. 1736—1819. Michael Faraday. 1791—1867. ILLUSTRIOUS PHILOSOPHERS OF A BYGONE ERA. Januaky 1, 1897.] KNOWLEDGE, on. These results, combined with those of other contem- porary workers, were slowly but surely producing a great transformation in the minds of thinking men. The universal belief in a six-thousand-year period as the age of the world had started on its retrograde course into dim antiquity, to which all the light of subsequent discovery can assign no limit, But to the great mass of the people, at the time of which we write, all this was a vast igno- rance. Popular opinion of that time (1837) was almost uniform in favour of the belief that all living things left the hands of the Creator just as we now see them. That environment — variations dependent upon food, climate, habitat, and other conditions — had any- thing to do with the form, size, or colour of an animal, or that insects had any con- nection with the scent, colour, and form of flowers, was a plane of thought too elevated for the circumscribed under- delicate injections, and by the practice of vaccination be- queathed to the whole civilized world a preventative for a disease the ravages of which formed one of the most terrible scourges to which ihe human race was ever subject. Erasmus Darwin (the grandfather of the greater Darwin) bad foreshadowed the theory of evolution in these words : " When we revolve in our minds the great simi- larity of structure which obtains in all the warm-blooded animals, mankind included, one is led to conclude that they have alike been produced from a similar living filament." Von Baer had, in 1828, shown that the embryo of a fish, a lizard, a bird, and an ox are not distin- guishable from one another, and continue growing so until a certain stage, when their characteristic forms become apparent. Animals could, therefore, be differentiated according to the special characters they assume from the beginning. Geoffrey St. Hilaire had demonstrated Faraday's Tube for Licniefving Cli'orine, etc. standing of the masses of that day. But the little leaven which has in the interim transformed the whole lump had begun to operate. John Hunter had pointed out the necessity of embracing and connecting all the studies relating to life, instead of limiting the science of biology to the study of simple forms through anatomy and physiology only. He raised surgery from a poor empirical art to a noble science, and founded the Hunterian Museum, where the organs of the animal body are displayed in all their morphological aspects. His illustrious pupil, Jenner, had displayed unrivalled skill in minute dissections and the unity of plan of the animal kingdom, and was one of those who believed all species to be derived by modification from primitive types. Sir Joseph Banks brought much influence to bear on the progress of science by diffusing the products cf other climates over each portion of the globe. He brought into Europe the seeds of the South Sea Islands, having previously distributed to the latter those of Europe. I'ut although evolution was then in what may be called the incipient stage, it remained to be proved and worked out in detail by the classic researches of Darwin. 4 KNOWLEDGE. [January 1, 1897. Most of the chemical elements were discovered before the year 1837. Five elements were discovered from the year 1839 to 1844, and five others were subsequently added after the general introduction of spectrum analysis. Dalton, in 1808, published the first volume of his new system of chemical philosophy, in which he placed the atomic theory on a firm basis, and established once for all the law of multiple proportions. Before Dalton's time chemistry consisted of a heterogeneous mass of separate chemistry became for the first time an exact science. Davy had laid down the laws of electro-chemical decom- position, and by their application discovered metals of the alkalies and alkaline earths ; while in 181G he bequeathed to the mining world his safety-lamp, which has served the double purpose of preserving life and increasing commerce. In 1828 Wohler broke down the barrier which was long supposed to exist between inorganic and organic substances. It was thought that organic substances could George Stephenson's " Rocket" (1829), the Forerunner of the Modern Locomotive Engine. {Hcijioditcf.d fi-oin the Ci^inji-i'jht Coloured Plate hu ^ermisr.ion of the Leadenhall Pixss^ Ltmited.) facts. The truth that chemical union between dissimilar bodies will only take place in absolutely unalterable pro- portions, as distinct from mechanical mixtures, is as imposing in grandeur as the law of gravitation itself. To follow the bearintrs of this great discovery in chemical science would be to reveal all the operations of the analytical chemist, and to exhibit the disparity between a scientific chemical manufacturer and the rule-of-thumb operator. By the promulgation of Dalton's views only be produced in the living bodies of plants and animals requiring for their construction not only chemical affinities, but a supposed rltnl force. But Wohler opened the way to a new field of scientific investigation by producing urea synthetically — that is, by building it up from its inorganic constituents. Allen had proved the identity of the diamond with charcoal ; while quite recently, it may be mentioned, Moissan has accomplished the extraordinary feat of trans- forming carbon from the amorphous to the crystalline January 1, 1897.] KNOWLEDGE. condition — that is to say, he has succeeded in making diamonds artificially. About the year 1837 electric telegraphs were first established as commercial speculations in three different countries. Steinheil's system was carried out at Munich, Morse's in America, and Wheatstone and Cooke's in England. The wires were buried in the earth, and were five in number, each acting on separate needles, the first telegraph line being on the Great Western Railway from Paddington to West Drayton. These initial attempts at telegraphy, clumsy enough when compared with the refined methods of our own time, were inspired chiefiy by the work of Faraday, who established the connection between magnetic and electric currents ; though Oersted, Ampere, and Schweizzer, by their respective discoveries of the deflection of a magnetic needle by an electric current, the foundation of electro-dynamics, and the electric coil, come in for a share of the credit ; while Sturgeon, who constructed the first electro magnet, should not be forgotten. Faraday, prior to the Victorian era, had succeeded in converting gases into liquids by subject- ing them to pressure in sealed tubes, and thus led the way in that series of grand experiments which later, in the hands of CaiUetet and Pictet, were to prove that there is no such thing as a permanent gas. In the domain of invention or mechanical science the contrast between the present time and the year 1837 is most striking. Sixty years ago the great railways were all begun, but not one of them was completed. The line between Liverpool and Manchesterwas opened in September 1830. In 183C it was carrying four hundred and fifty thousand passengers m the year. There were also a great many lines projected, which afterwards settled down into the present great trunk lines. At that time a writer in the Atht-n-cewii says : " When these lines are completed, letters and passengers will be conveyed from Liverpool to London in ten hours. Little attention has yet been given to calculate the effects which must result from the establish- ment throughout the kingdom of great lines of intercourse traversed at a speed of twenty miles an hour." There were no hansom cabs, and no Parcels Delivery Company, There was a twopenny post, but no penny post and no book post. It was not till 1888 that the .'Sirius and Great ]\'estcrn first steamed across the Atlantic. In the main, however, there was no means of transporting man, merchandise, or message quicker than a horse could take them. The result was an isolation of town from town, and of the country from London, which made between the England of that day and the England of our own time a difference which will be appreciated by all. There was no single daily newspaper published outside London. It was a society unfurnished with these things that Queen Victoria began to rule over in 1H37. The electric telegraph, making, as it now does, the whole civilized world all of a-piece, through which it ramifies like a vast nervous system, had not then linked the sovereign with every part of her dominions. America and Australia were then practically unknown to the bulk of our people. In short, the nineteenth century actually began with steam communica- tion by sea, with steam machinery, with railways, with telegraphs, with the development of the colonies ; but all these transforming influences were in reality nothing more than the dawning of the brilliant Victorian era, which has made its indelible imprints on the scroll of history. The men pourtrayed on the plate accompanying this article are representatives of the philosophers of the latter part of the eighteenth and the first half of the nineteenth centuries, who, by the impetus they gave to science, pre- pared the way for those grand generalizations which have lent to the Victorian era such a glorious halo. John Dalton was born at Manchester of a Quaker family, and the chief work of his life was a clear enimciation of the theory of atoms — known as the atomic theory. Sir Hum- phry Davy hailed from Cornwall, and while still very young discovered nitrous oxide (laughing gas), which led to his appointment as the first Professor of Chemistry in the Royal Institution. Michael Faraday, as Davy's assistant, exhibited great ingenuity, which ultimately led to his appointment as his chiefs successor. His discovery of the production of an electric current by the rotation of a magnet has led to many applications of electricity. Sir Joseph Banks was a man of private means, and went round the world, as botanist, with Captain Cook, in the years 1768-1771. He bequeathed his valuable library and herbarium to the British Museum. James Watt, born in Greenock, became a mathematical instrument maker in London, but his chief work was the improvements which he introduced in the construction of the steam engine. Sir Wm. Herschel, born at Hanover, came to England in 1757. He was by profession a musician, being organist at Halifax parish church at one time and at the Octagon Chapel, Bath, at another. But, later, astronomy attracted his attention, and, after making his own tele- scope, he discovered the planet Uranus in 1781. John Hunter, born at Long Calderwood, was the greatest anatomist and surgeon of his time. At his death 10,563 specimens and preparations illustrative of anatomy, physiology, pathology, and natural history were found in his museum. Edward Jenner, Hunter's pupU, was born at Berkeley, in Gloucestershire. He was first led to study vaccination by hearing a countrywoman remark that she could not take the small-pox because she had had the cow-pox. ^ - ON DESCRIBING AND DRAWING INSECTS. By Fred. Enock, F.L.S., F.E.S. IT is not until an entomologist takes upon himself to study, or work up any one of the many neglected families, so plentiful among the Parasitic Hymen- optera, that he finds how difticiilt it is to identify his captures, either from published descriptions or drawings. If his dwelling-place be in London he has many advan- tages over his brother entomologist in the country. In Greater London there is no lack of species ; some of the rarest and most beautiful can be found in almost any back garden — in fact, the number that can be obtained in such places by the process of sweeping is astonishing. As soon as we have " set " our captures and numbered each specimen, our next desire is to name them. Now we find this decidedly a difiicult matter, and many of our specimens continue to be known only by the number written on each card. Our next effort towards naming is made by visiting the Natural History Museum, South Kensington, where we vainly endeavour to find named representatives of our captures in the glazed cases of insects in the " British Gallery " ; but, alas ! we are soon doomed to disappointment, the covers are replaced, and we return home wondering why there are so few British insects there. I have frequently found young naturalists engaged in a simOar hopeless task, and directed them to the Insect Room, where students of either sex, old or young, are always welcome to examine the vast collections of insects, brought from all parts of the globe. Gorgeously coloured foreign insects of all orders, tens and hundreds of thousands of named species, in the most 6 KNOWLEDGE, [January 1, 1S97. exquisite order, over which our eyes wander, fascinated by their wondrous beauty, so apparent to the naked eye. But these are not the insects which we desire to see. We have our treasures in a very small bos, and we ask one of the obliging "staff" to allow us to examine the British Parasitic Hymenoptera, which are contained in a few drawers, comprising the collections (or part) of such ento- mologists as A. H. HaUday, lo whom we are indebted for most of the drawings published. Francis Walker, too, has added greatly to our knowledge of British Chalcididir, and will always be gratefully remembered for the kindly help which he so readily and ably gave when at the old museum. Many specimens there are, too, collected by Frederick Smith, to whom I am personally indebted for much help. To these must be added the name of J. O. West- wood, who was, without doubt, the most wonderful entomological draughtsman. These grand old naturalists have all passed away, and we look around in vain for those who can fiU their vacant places. The enormous influx of foreiiin specimens of all orders appears to have entirely swamped our indigenous collections, the amount of study and attention devoted to this branch of British entomology being in strict proportion to the size, viz., microscopic. After spending some hours in examining and comparing specimens we find our time is up, and the result of our labour in naming very small. Subsequent visits to these collections did not prove very helpful, for we were like the old farmer, who, when sipping claret at a dinner, was asked how he was getting on, replied, " I don't get no forarder ! "' This sage remark reminds me that I must endeavour to go forward with the object I had in view when first taking up my pen, and to impress upon all naturalists the im- portance of keeping a daily journal of observations upon insect life, noting down in black and white every fact connected with the economy and habits of such insects as we are studying or which pass under our observation. There are many ways of keeping such journals. For my own part I use a manuscript book, six and a half inches wide by eight inches deep, each page cross-ruled into quarter- inch squares, which give invaluable help when drawing to any scale, and which can be decreased or increased by again dividing the squares or doubling them. Each page is headed with the year, the first two columns are occupied by the day of the month, followed by a consecutive number to each observation. These numbered paragraphs are duly indexed under the various subjects to which they refer. Specimens for the cabinet are labelled with a corresponding number, while, in the case of such mounted in balsam for the microscope, the number is scratched on the glass with a writing diamond. When some such plan of recording daily observations is kept, the amount of information stored is astonishing. This, when systematically arranged, often reveals the life history of some insect almost complete, with only one or two missing links, which should be specially marked to receive extra attention during the next season. Owing to the irregular methods which some authors adopt in their descriptions of insects, the task of naming is made more difficult. No two insects are described in the same order. Head, thorax, abdomen, legs and wings, in one: then in the next some other plan, making com- pariaon of parts most confusing, whereas a little more thought would make examination far easier to both author and student. So convinced am I of the advantages of thus doing, that I have written out upon a piece of card the following " instructions," which I place close to my microscope whenever I am detcribing some new capture. Thorax. M'ings. Legs. Obdee of Description. Read. Size, shape, and sculptiu-e. Colour. Ocelli. Positiou. Eyes. Colour, shape, and position. Maudihles. Colour and shape. Troplii. Shape. Joints in palpi. Antennse. Comparative length. „ Number of joint i. ,, Scape, colour, and shape. „ Pedicel, colour, and shape. „ Ring joints. ,, Funicular joints. „ Club. ,, Position when at rest, etc. Width and shape. Colour, markings. Sculpture. Under side. Size, shape, neuration, colom*, cilia. General length. Colour. Coxie, trochantei's, colour, hairs, etc. Femora, colour, hairs, etc. Tibiie, colour, hairs, etc. Tarsi. Xiimher of joints. Abdomen. Petiolate, sessile or sub-sessile. Colour and sluipe. Pose. Ovipositor. Genitalia. I venture to give these " instructions " to those who are desirous of becoming something more than mere collectors, and though such may, at first sight, appear somewhat dry and monotonous, I can assure all young naturalists that they will find such work most fascinating as the eye becomes more highly educated in its power of observation. These examinations must be carried on under the microscope, with an inch and a half-inch objective. Whenever it is possible, make out your descriptions from livini/ insects, when so much more purpose can be seen in the various parts, many of which contract and dry up out of sight in a dead specimen. I often think that much of the dryness or dulness of de- scriptive entomology is attribut- able to the fact that it has been made from lifeless creatures. No doubt such work will try the patience and temper of most of us ; but the immense advantage gained, enabling us to follow out the movement and purpose of almost every hair or peculiarly formed spine, fully repays us for the extra trouble. The pleasure and instruction received when watchinga minute fly confined in a small glass- topped pill-box is most delightful. The first operation engaged in is to free itself from every particle of dust and dirt. It is when so occupied that we are able to jot down our notes as to the form and colour of some of the most minute parts. The pose, too, of the antennas, head, and whole creature can only be observed in a living insect ; the mysterious light in the eyes and the ever-changing prismatic colours on the gauze- like wings, all can be seen, and all appeal to our suscepti- bilities. We feel that we have looked a little way above and beyond such things as " the point of a needle highly Fio. 1. — Drawing of part of the upper wing of a minute Hymenopteron. JANUARY 1, 1897.1 KNOWLEDGE. Fio. 2. — Pboto-iuicrograph of tbo upper wiug of a miuute Hynicnopteron, from Nature. magnified," with which so many are charmed, apparently unable to grasp anything not made by human hands. Great as the pleasure is which we obtain from minutely ex- amining and describing an insect, it can- not compare with that derived from making a drawing of one of these marvels of creative skill, and those who desire to increase their power of ob- servation I recommend to place a small insect in position under an inch objective, and then to make an ed-(ict drawing of it. This should be made on the sectional paper, or, best of all, in the journal, where the squares can be either divided or doubled according to the scale. We must, when thus engaged, bear in mind that we are not making a freehand drawing or one in which we can put in any of our own ideas, for the insect is not like a weed, say, of grass, where the leaves turn and twist about in all directions. We shall find before we have been di awing for an hour that every hair and spine has its place and peculiar form ; some perfectly straight, others bent over in a graceful curve; another on the oppo- site side bend- ing over to- wards it in exactly the same curve. In a freshly emerged fly, or even in a tiny larva just hatched, and before it has received any rough hand- ling, can be seen numerous hairs on each segment, every one placed most exactly to cor- respond with those on the other side of the centre line, over which some of them cross in graceful form, meeting exactly over the centre ; others bending forward and away again in such marvellous order that no one can fail to be convinced of the evidence of design in cvsry hair and spine, each one of which is so exquisitely fitted into and held by the skin tbat the desired movement and allotted function can be performed with the greatest ease. Fig. 3. — Photo-uiicrograpli of tongue of Bee wliieh lias been soaked in liquorpotassa, squeezed Hat between two pieees of glass, washed uud dried, then mounted in Canada balsam. All engineers' draughtsmen, when designing any mechani- cal work, know the vital importance of allotting to each bolt and rivet its place, so that from foundation to finish all work together without confusion. So it is with every insect, any one of which, as we go on drawing, draws out our wrapt attention, until we feel spellbound with the \\\)^tf Fio. -1. — Tongue of Bee as seen in its natural form. inexpressible and marvellous manner in which it is put together. With such a copy no liberty ought to be taken, but faithful representation made, to the best of our ability, of these works of creation. All drawings should be carefully inked in and the scale marked under each. To show how necessary it is that greater care be taken in drawing minute insects, I give a few instances, without names of either author or insect. On comparing Figs. 1 and 2, it is at once apparent that the artist has not studied his subject, but simply noticed that the wings have long hairs all rouud, the photo- micrograph proving that the drawing has almost twice the correct number of these characteristic hairs, which I havo found constant in over sixty specimens. These peculiar paddle-shaped wings are unique, so that anyone capturing this insect would recognize it from the incorrect drawing. Fig. 3 is a specimen of "wicked distortion" to which insects are subjected, showing the various parts utterly ruined, with little or no resemblance to the original form. Drawings or photo-micrographs of these flattened prepara- tions convey but a poor idea of the original insect. Drawings made of minute insects, mounted in the usual 8 KNOWLEDGE. [January 1, 1897. method on pieces of cardboard, are liable to serious error unless the greatest care be taken to prevent the Fig. 6. Fig. 5. — An insect witli its wings on the riglit hand properly set, those on the left showing contraction due to careless setting. ■wings from being drawn up towards the thorax as the gum dries, the consequence being considerable shortening and distortion of one or both wings. Fig. 5 shows an insect with its wings on the right-hand side properly expanded and " set," the tips just touching the card. The left-hand wings have been drawn in by the contraction of the gum, thus not only fore- shortening the wing, but preventing the short costal nerve from being seen. This is the cause of many mistakes. Figs. G and 7 repre- sent two minute Hy- menoptera, upon whose structure so little detail has been shown that most strange errors have crept in concerning their identity, and handed down and copied by authors, who, by so doing, prove howvery little attention they give to studying these creatures, except from books. In conclusion, I would urge upon all entomologists and others the vast importance of acquiring and pursuing the habit of making most careful observa- tions anddra wings of these small in- sects, about which we Icnow so Uttle when we ought to know so much. They are our best insect friends, without whose help, by keeping in check noxious pests, we should scarcely be able to exist. In future articles I propose to describe some of our common insects whose life-histories have not yet appeared in print. Fig. 7. THE SPECTRUM TOP. By T. L. Alger, LL.D., Ph.D. AS I look around me, and into the sayings and doings of workers in the fundamental principles of Ught, I do not find that a perfect synthesis of white light has been obtained so as to embrace the law of the combination of pigments. The principle of selective absorption does not appear to me to entirely settle the matter. It is patent that the crossing of the elementary beams of the solar spectrum — the red, the green, and the violet rays — can be made to coalesce on a screen and form a patch of Ught which has more or less a bluish or greenish fringe ; but that, when the same colours as pigments, or their nearest approach, are marked out on a disc, and set revolving by means of a multiplying wheel, the effect pro- duced is not pure white, but the grey of a combination similar to that of a disc divided according to the same law in black and white, and set revolving in a similar manner. Now, the question occurred to me, was it possible to place a tricolour painted disc under circumstances that could produce a pure white light ? I first took a disc of white cardboard about two inches in diameter, and divided it into two equal portions by a line passing through the centre of the disc, and painted one-half of the disc black. I then divided a similar disc into four quadrants, and blackened the alternate ones, and another similar disc into eight half-quadrants. On ap- plying the multiplying wheel in all these cases, I produced the same tint of grey as would be produced by mixmg in equal proportions black and white pigments. I therefore came to the conclusion that the equal distribution of black and white on the disc, under different arrangements, pro- duced the same effect — the grey. In these experiments I failed to trace the slightest prismatic colour. On covering other and larger discs with red and blue, red and yellow, and other combinations of what in Newton's days were known as primary colours, I found a similar effect, /.('., the red and blue produced violet, the red and yellow, orange, and the blue and yellow, green : (.-•-. — The process of vulcanizing india-rubber by means of bisulphide of carbon, and the operations incidental thereto, have been condemned by the Home Secretary as dangerous or injurious to health. 14 KNOWLEDGE. [January 1, 1897. Iron ore is plentiful in Sussex, -whicli, until the year 1720, was the principal centre of iron manufacture in England, the iron rails round St. Paul's Cathedral having been cast there. The fuel used was wood, but the country became denuded of timber, and Parliament prohibited smelting operations, the last furnace being extinguished in 1828. Now it appears, in view of the development of a coalfield at Dover, the re-establishment of ironworks on a large scale is contemplated. — t » I A Victorian Era exhibition, under the auspices of the Associated Chambers of Commerce, is to be held during the present year. Its object is to bring together exhibits illustrative of the progress effected in different branches of British trade during Her JIajesty's reign, as well as the present condition of the manufactures of the United Kingdom. An exhibition is to be held early this year at the Imperial Institute illustrating the great progress which has been made in carrying on the sea fisheries of the United Kingdom, the advance made in yachting, and the perfection to which life-saving apparatus has been brought during the sixty years of Her Majesty's reign. Agriculture in the West Riding of Yorkshire is said to be seriously retarded through the havoc wrought by sparrows, which at present fairly consume the produce of the field, and are preparing for the farmers a highway to bankruptcy. As remedial means, it has been suggested that the old sparrow clubs shoiild be revived, a halfpenny per head to be offered for every sparrow killed. Wm. Crookes, F.R.S., of thallium and radiometer fame, in lecturing on " Diamonds" at the Imperial Institute on the 7th December, disclosed some interesting facts. He mentioned that the four principal mines (Kimberley) em- ployed about eight thousand persons. From two to three million carats of diamonds were turned out in a year, and up to the end of 1802 ten tons of diamonds, valued at £60,000,000, had come from those mines. In 18i»5 there were found 2,135,541 carats of diamonds, realizing £'3,105,058, at an expenditure of £1,701,813, and leaving a profit of £1,401,145. The largest known diamond, weighing 970 carats, was found at .Jagersfontein Mine, and was now being cut at Amsterdam. But even diamond mining has limitations, for Mr. Crookes said the mines were capable of yielding more, but they were limited to a certain output in order to maintain the price. The eleventh German Geographical Congress will be held at Jena on April 21st, 22nd, and 23rd. The principal subjects to be discussed are Polar investigations, physical questions, biological geography, the topography and natural history of Thuringia, and the teaching of geo- graphy in schools. Referring to the beet sugar industry of France, the United States Consul at Havre says, in a recent report, the crop pays the farmer better than wheat or any other agricultural product, and hence a large acreage is under beets. In 1894 the area was one million seven hundred thousand acres, and the production nearly eighteen and a half mOlion tons, or nearly eleven tons to the acre ; fifty to sixty per cent, of all this is used for the production of sugar. It is said that the leaves of the plant are used for adulterating tobacco. The pulp, after the juice has been expressed for sugar, is eaten by cattle. At the London Institution, on December 4th, Mr. Fred. Enock, F.L.S., delivered a most interesting lecture on " The Wonders and Romance of Insect Life" as pourtrayed in the life histories of some of the insects common in every London back garden. The fifty illustrations shown upon the screen were the handiwork of Mr. Enock, each one a study from nature, showing the metamorphoses of the various insects. Many of the marvellous insect egg parasites have been discovered by the lecturer, who is engaged upon a monograph of this most interesting but neglected family. •-•-• Rumour has it that a scheme is on foot for the furnishing of electric power to the city of Mexico from peat beds nine miles distant. Some idea of the great activity of the inventive faculty at the present time may be formed from the fact that in the week ending November 28th the number of applications for patents filed at the Patent Office amounted to seven hundred and seven. An analysis of this great muster of things new and, alas ! old, shows that, eliminating the vast number which relate to cycles, thirty-nine aim at improvements in the applications of electricity, including the electric lighting of cycles and motor cars. BOOKS RECEIVED. Zoolofjical Socieftf of London, List of flip Vertehraied Aninwls now or latehi Living in the Gardens. Ninth Edition. (Longmans.) Illustrated. Journal of the Might Hon. Sir Joseph Sanhs during Captain Coot's First Voyage in S.3I.S. " Endeavour." Edited by Sir Joseph D. Hooker. (Macmillan.) Illustrated. 17s. Autohiographical Sketch of James Croll, LL.D., F.S..S., with Memoir of his Life and Work. By James Campbell Irons, M.A. (Stanford.) 12s. Botanical Microtechnique. By Dr. A. Zimmermann. Translated from the German by James Ellis Humphrey. (Constable.) Illustrated. 12s. net. Practical PhgsioJogy and Hisfologg. By M. Foster, M.D., F.R.S., and J. N". Lang'ley, M.A., E.R.S. (Macmillan.) Illustrated. 7s. 6d. The Aurora Borealis. By Alfred Angot. (Kegan Paul.) Illus- trated. 5s. Roentgen Sags and Phenomena of the Athode and Cathode. By Edw. P. Tliompson. (D. Yan Nostrand Company ) Illustrated. 7s. 6d. European Architecture. By Riissell Sturgis, A.M., Ph.D., F.A.I.A. (Macmillan.) Illustrated. 18s. Memoirs of the late Prof. Charles Pritchard. Compiled by his Daughter, Ada Pritchard ; with an Account of his Theological Work by tlie Bishop of Worcester, and of his Astronomical Work by Prof. H. H. Tu]-ner. (.'ecley & Co.) 10s. 6d. The True Grasses. By Edward Hackcl. Translated from " Die Naturlichen Peflanzenfamilien " liy F. Lamson-Seribner and Efiie A. Soutbworth. (Constable.) Illustrated. 10s. 6d. net. Practical Electricitg. By W. E. Ayrton, F.E.S. (Cassell i Co.) Illustrated. 9s. Electro-Physiology. By W. Bicdermann. Translated from the Grerman by Frances A. Welby. (Macmillan.) Illustrated. 17s. Marletahle Marine Fishes of the British Islands. By J. T. Cunningham, M.A. ; with a Preface by E. Eav Laukester, M.A., LL.D., F.R.S. (Macmillan.) Illustrated. 7s. 6d. net. Elements of General Philosophy. By Groorge Croom Robinson. Edited from notes of Lectui-es delivered at the University College, London, 1S70-1892, by C. A. Foley Rhys Davids, M.A. (Murray.) 3s. 6d. The Earth and its Story. By Angelo Heilprin. (SUver, Burdett, & Co., New York.) Illustrated. 5s. The Story of the Chemical Elements. By M. M. Pattison Muir, M.A. (Ncwncs.) Illustrated. Is. ll'ood Carving. By Joseph Phillips. (Chapman & Hall.) Illus- trated. E.rperiments vpon the Contraction of the Liquid Vein. By II. Bazin. (Chapman & Hall.) Ss. 6d. net. A Te.rt-Boo/c on Shades and Shadows, and Perspective. By John E. Hill. (Chapman & Hall.) Illustrated. 83. 6d. net. Januaey 1, 1897.] KNOWLEDGE. 15 Elements of Differential Calculus, By Edgar W.Bass. (Chapman & Hall.) 17s. net. Notes for Chemical Students. By Peter T. Austen, Ph.D. (Chapman & Hall.) 6s. 6d. net. Diagrams of Terrestrial and Astronomical Objects and Phenomena. Bj K. A. Gregory, F.E.A.S. (Chapman & HaU.) 21s. net. Whitaler's Almanack; 1897. (Whitaker.) 2s. 6d. Light as the Interpenefration of the Law of Graviti/. By Alexander M. Cameron. (Angus & Kobinson, Sydney.) Confidences of an Amateur Gardener. By A. 11. Ilewsmith. (Seeley & Co. ) Illustrated. 6s. Charles Danciii and the Theory of Natural Selection. By Edward B. Poulton, M.A., F.E.S. (CasseU & Co.) Illustrated. 3s. 6d. Smithsonian Contributions to Knowledge. (Wesley & Son.) — " Life Histories of Jforth American Birds"; "Oceanic Ichthyology"; " Argon : a Jfew Constituent of the Atmosphere " ; " On the Methods for the Determination of Organic Matter in the Air." (Smithsonian Institute.) Illustrated. London University Guide and University Correspondence Calendar, 189S-7. (Cliye.) Hygiene for Beginners. By Ernest Septimus Reynolds, M.D. (Maemillan.) Illustrated. 23. "6d. The Story of Forest and Stream. By James Eodway, F.L.S. (NcMTies.) Illustrated. Is. A Handhool- of the Game Birds. Vol. II. By W. R. OgUyie- Grant. (Allen & Co.) Illustrated. THE AGE OF MOUNTAINS.-I. By Prof. J. Logan Lobley, F.G.S. THE marvellous foldings and plications of rocks observable in mountain and hill ranges, which were lately described in Knowledge, »- suggest an inquiry as to when they were produced. To reply to this inquiry a knowledge must be obtained of the geological age of the elevations exhibiting these great and wonderful phenomena. " The everlasting hills " is a phrase with which we are aU familiar; indeed, we are so accustomed to look upon a mountain as a type of all that is stable and enduring, that it would to many be somewhat startling to be told that the hnis and the mountains of the globe are constantly changing and being worn away, and much more so to be informed that, compared with the age of the oldest rocks, many are but things of yesterday. But it is well known to all observers of nature that every rainstorm, every torrent, carries away from the summits and sides of hills and mountains a large amount of solid material ; that ice, and snow, and frost, and thaw, take from the peaks and the higher regions of lofty mountains enormous quantities of the hardest rocks ; that these are hurled down to the base of the precipices, and carried to the rivers of the plains. The " screes " of our own Cumberland Lake District, and the broad desert of stones derived from the summi's of the Alps, which in the dry season extends as the wide bed of the River Po for hundreds of miles , are but obnous illustrations of the rapid waste of hUls and moun- tains. The great plain of Lombardy itself has been formed by the filling up of a shallow sea with the debris brought from its bounding mountains. It is not, however, to the wearing away or destruction of mountains to which attention is now invited, but to their various ages and the comparatively recent elevation of many of the mountain ranges of the globe. By the " age of a mountain,'' it must be borne in mind, is not meant the age of the rocks of which it is composed, but the age of the mountain as the elevation we now see it, or, in other words, the geological period in which it assumed that prominence and importance as a feature of the earth's surface which is given to it by a considerable elevation above the level of the sea. The maximum geological age of a mountain can be approximately fixed by ascertaining the age of the most recent of the rocks occurring at a considerable height above its base, since ihese rocks must have been formed under water at a low level, and so must be older than the elevation which placed them at the level they now occupy. In order to determine the geological age of a mountain it is requisite, therefore, to ascertain the most recent or newest strata forming any part of its summit or flanks. It can then safely be said that elevation, and to that extent, has taken place since the period of the deposition of those recks. But it cannot be safely said that the range is of later date than the geological epoch of the formation to which the most recent strata belong, because the periods during which the " formations" of the sedimentary rocks were individually deposited were each of such long duration. As was well shown by Sir Charles Lyell in reply to Mr. Elie de Beaumont's arguments in support of the theory of the sudden rise of mountain chains, it was quite possible for a mountain range to be partly composed of Cretaceous strata, and yet to have been upheaved in the Cretaceous epoch. The period indicated by that phrase was of sufficient duration to allow of deposition, accumulation, consolidation, upheaval, and great elevation, and even of subsequent sub- sidence beneath the waters of the ocean. And the same might be said of the other great geological epochs of the earth's history. Unless there be other evidence, therefore, it can only be said that the elevation took place since the commencement of the epoch of the latest rock, or subse- quent to the close of the preceding period. There may be other evidence, however, which will enable a more positive statement to be made, since we can, by a knowledge of the geology of a district, even assert that an elevation within its area is of later date than the close of the epoch of the rock of which it is composed. An example is not far to seek, and one on a small scale is in the im- mediate neighbourhood of London. In the Thames Valley there are several elevations rising to the dignity of hills. Those which attain a certain elevation, as Hampstcad and Harrow hills, are capped by sands, which cappings are outliers of the Bagshot Sands, the hiUs below these sands being composed of the London Clay. From this it cau be asserted that the lower hUls, as the Norwood hills, although not capped by Bagshot Sauds, are also newer as separate elevations than the deposition of the sands of the higher hills, since they have all been the result of cu-cum- denudation during the same period. V0LC.\NIC .MOUNT.UNS. Volcanoes are so distinctly different from all other mountains in form, structure, and origin, that they should obviously be considered separately, and placed quite apart in any consideration of mountain age, although they are -See KxowLEDGE, July. 1896. Eio. 1. — Prehistoric Vesuvius : a Single Cone. often, parasitically, as it were, situated on a mountain range. In many cases these volcanoes are lofty mountains, with beautifully regular conical summits. These thus attract the eye even when surrounded by still greater elevations, and often give much beauty and great interest to the scenery from amidst which they rise. The origin and 16 KNOWLEDGE. [January 1, 1897. formation and structure of volcanoes are by no means obscure. Von Bucb, Humboldt, and others held the opinion that they have been formed by upheaval, and have their upper portions only composed of ejected matter. It is now, however, conclusively established by observation of sections of cones, and especially by the formation of Monte Xuovo, near Baice, which was actually observed in the year 1588, that a volcano is simply an accumulation of ejectamenta around a central orifice. All the active volcanoes of the world are, therefore, mountains in course of formation at the present time, and, so to speak, not yet completed. Many of them, too, were only commenced in very late geological time. The best-known of all volcanoes, Tesunus and Etna, may be taken as types of the present day active volcanoes of the world. Vesuvius, including the old crater ridge of Monte Somma and the gigantic cone of Sicily, had a late Pliocene beginning. One very interesting fact in connection with the formation of mountains by volcanic action is that such action sometimes destroys as well as builds up, and often lowers the height of a volcano. This is strikingly exem- plified in the history of Vesuvius, for in prehistoric times this mountain was, there is little reason to doubt, at least double its present elevation, and in historical and even in recent times the present cone has been greatly reduced in height by unusually great or paroxysmal eruptions. Small eruptions increase the elevation of a volcanic cone, whOe great eruptions lessen it by blowing ofi" its upper- most part and so increasing the size of the crater, as is shown by the accompanying illustrations.* But perhaps the most conspicuous illustration of the destroying action of volcanic energy was that afforded only about twelve years ago at the island volcano, Krakatoa, in the Sunda Straits, an interesting account of which terrific eruption appeared in Knowledge for December, 1895. The volcanic mountains next in age are those which have been quiescent for many centuries and so are thought to be extinct, but yet have been in eruption during the historic period. Monte Epomeo, in the Island of Ischia, in eruption in 1302, is an instance of this class, as is also the lofty mountain in the North-West of Arabia, con- sidered by some to be the true Mount Sinai, and which is Flo. 2.— Cone Truncated bv C4reat Eruptions. stated by the Arabs to have been in eruption in ancient times. The singularly regular and beautiful cone of Fusi Yami, in Japan, is, too, an excellent example, as is also the Solfatara of the classic Phlegrean Fields. The many mountains that have been built up by volcanic action since Pliocene times, and have yet never been active since the commencement of the historic period, constitute a still older class. Nowhere furnishes better examples of the prehistoric volcanoes than Auvergne in Central France, where volcanic cones and craters are exceedingly numerous, and no less than forty cluster around the Puy de Dome and form the beautiful district near Clermont. These have been made extensively known by the admirable and profusely illustrated work of Poulett Scrope, " The Volcanoes of Central France." * From "Moimt. Vesuvius," by J. L. Lobley. Although the Puys of Auvergne are undoubtedly pre- historic as active volcanoes, yet some of their craters are so perfect that they cannot belong to a period more remote than that immediately preceding the present epoch. That the greater portion of the mass of these mountains is of post-Pliocene age is obvious from their lavas covering Pliocene strata, though the volcanic action here com- menced, probably, in that period of great volcanic dis- turbance, the Miocene. Doubtless some ceased their activity long before others, as the craters of a few of the Puys are much worn and wasted. To the same era may be assigned the great volcanic mountain of Cantal, and the other extinct cones of Central France. Of this general age, too, are the beautiful and interesting volcanic hills in the district of the Eifel, near the Ehine, the crater of one of which forms the Lake Maare. Better known are the extinct volcanoes near Eome, displaying fine examples of lakes of placid water occupying craters once the scene of violent volcanic action. Lago di Bolsena, occupying one of the largest craters in the world. Fig. 3. —Vesuvius after Eruption of 1G31. Lago di Braceiano, and the well-known Lake of Albauo, are perfect examples. From the volcanoes of the Alban Hills the material was ejected that now forms the tufa constituting the " Seven Hills " of Eome. The famous Lake Avernus and the Lago Agnano are lakes in craters of this age near Naples; and the hills, and indeed the whole site of that great city, are formed of the ejectamenta of those and other neighbouring craters. The great volcanic mountain of Tatra in the North of Hungary, and other volcanic elevations on the flanks of the Carpathians and in Transylvania, may be ascribed to the earlier Oligocene period, and the high basaltic lands of South AustraUa and Victoria to Eocene volcanic action. One of the greatest outpourings of lava the world has seen occurred in Cretaceous times, and formed the high plateau of the Deecan in India, where volcanic rocks, covering an area of two hundred thousand square miles, have a maximum thickness of no less than six thousand feet. To this period also belong vast uplands of volcanic rocks in the West of the North American continent. Though in the older geological periods volcanic activity gave vast thicknesses of rocks now occupying elevated positions, and sometimes forming hills and even the sum- mits or parts of the summits of lofty mountains, yet the Fig. I. —Vesuvius as at Present. hills and mountains of which they now form portions were elevated in most cases subsequently to the outpouring of the lava, since it is interbedded with sedimentary rocks. Conspicuous examples of this are seen in the Welsh Januasy 1, 1897.] KNOWLEDGE, 17 mountains of Snowdon, Cader Idris, the Arenigs, and others, and in the Scotch districts of Skye, Aran, the Pentlands, the Ochils, the Sidlawg, and many other hills, including the well-known Arthur's Seat. The age of such mountains and elevated lands must be fixed obviously by the geological considerations applicable when we approach the determination of the age of ordinary or non-volcanic moimtains. There is, however, one very striking example in our own country of a lofty mountain mass being formed of volcanic rocks that have never been interbedded. This grandly towers above Borrowdale and the beautiful Derwent Water of the Enghsh Lake District, and is of the Lower Silurian age. One of the vents of this old volcanic area, now filled with hard volcanic rock, was probably what is at present known as Castle Head, near Keswick. Still older volcanic rock forms a part of the Wreckin, in Shropshire, which has been ascribed to pre-Cambrian or Archcean times. BIRD-SONGS IN WINTER. By Ch.\rles a. Witchell. THE astronomical date of the commencement of winter being so much later than that popularly assumed for this event, it may be well to state that for the present purpose the former interpreta- tion has been adopted. The songs of birds will, therefore, be discussed as they may be observed during practically the three first months of the year ; for the con- cluding days of December do not induce any vocal variation from what was audible immediately prior to the shortest day, unless, indeed, the weather be remarkably nuld. It is quite possible that birds perceive the lengthening of the last days of the year ; but I have never detected anything in their behaviour indicating an appreciation of this circumstance as foretelling the spring. A few warm days, even in the darkest period of the year, wiU have more eflect in calling forth their songs than several additional hours of sunshine on a very cold March day. On the other hand, a few nipping frosts will silence the robin, thrush, wren, and hedge sparrow, although the starling will often sing on through the cold, especially if sure of obtaming food. If the weather at the beginning of January be fairly even, however, and not too cold, the lark will indicate the change of season by attempting a song. Year after year I have noticed that under these climatic conditions the bird renews its vocal efforts within a few days after New Year's Day. Some of the larks — probably old birds which were singing in October and November — now give songs which are coherent and varied, though not nearly so continuous and diversified as the notes heard in ^larch and April. For this reason the songs of the lark in January are a very interesting study, since their gradual elaboration from simple to complex modulations may be easily observed. The song is uttered more particularly during the first hour or two of morning sunshine ; and this habit is continued throughout the season of song. The bird does not now often sing while rising from the ground, as is customary in JIarch and later. One will fly hoveringly, and with a kind of lilt, in an aimless manner, at a slight elevation, and will then repeat its ordinary call-note, which sounds like u-orrij you pronounced very quickly. It may then utter another call — the cry of the young, which may be suggested by tieuu, and then change the other cry to iiorry u-orrij tvomjijuu, uttered very rapidly, and so on. That is how the bird begins to sing. The distinguishable mode of flight employed during song (except in a strong breeze) is now always exhibited before the song is commenced. In autumn the lark often employs the ordinary call-note singly while flying, and at such times the note is uttered at the moment corresponding to that in which the wings are flapped. It is possible that this may account for the hovering kind of flight being now emplo\-ed when the call-note is frequently repeated. The lark appears to be the first bird which begins to sing in the new year. Others may have been vocal during warm weather in December, such as the robin, thrush, starling, bro\\Ti wren, hedge sparrow, and, occasionally, the blackbird ; but the lark is less likely than any of these to sing at Christmastide. At the time when it is beginning to sing, or a week or two before, some of the hedge sparrows, probably birds of the last season, utter the simple call-squeak of their species twice or more times together, and thus make a little song. But this seems to be only a transitory accomplishment, and is soon varied by the introduction of other notes, the whole being very rapidly uttered. On a warm day in December or January the nuthatch repeats his short, low-pitched, and full-toned cry, tuuttutt, several times very rapidly in succession, and thus pro- duces a song which may be represented by ticuttuttuttutt. Although these repetitions do not, in December and early in January, generally exceed from three to six in number, uttered at the rate of about four per second, in February and later the repetition is often prolonged and executed with much greater rapidity, so that ten or twelve notes per second are produced, the general character of the whole reminding one of the whistling of a railway guard. In this development the nuthatch exceeds the degree of repetition observable in the lark and hedge sparrow. Early m January, however, he may also be detected in developing another cry from the ordinary call-note. Instead of the dissyllabic cry above described, a single full note ! (ticutt) is given, and is prolonged, sounding like a very [ short full whistle. As days pass the bird wiU prolong i this more and more, untO we hear long slurred whistles of much the same character as those we produce with the mouth when whistling to a dog. At the same period the tree-creeper may be heard repeating his somewhat plaintive call-squeak several times together, and he does this in any weather ; but the single note, though often prolonged, never attains so great a development as the whistle of the nuthatch. About March, however, the bird will repeat his squeaks so rapidly as to make a little song, which increases in quickness of utterance towards the termination, and may well be quoted as proving how pleasant a result can be attained by the simple reiteration of one cry. The above birds are mentioned as to some extent com- mencing their songs in January ; but, as already stated, there are others which, like the lark, have been singing in the autumn, but have not also ceased in December. If winter arrives with a spell of severe frost, however, these birds are silenced, and afterwards, when the thaw arrives, they begin to "record" or slowly recover their songs. The wren is rather exceptional, for it sings much the same song at any favourable time of the year, although in the season of nesting it will greatly prolong its little melody by repeating the same strain several times in one song. Early in January the thrush sings only brief songs — totee totec tceuu treuu, and other simple cries, which may be considered as the most widely prevalent in the species, and as probably representing the ancestral song. The rapid musical strains, some of tbem beautiful roulades, which the bird gives later in the season, are never heard now, nor are many cries uttered which resemble those of other species ; but in regard to the latter point it should 18 KNOWLEDGE. [January 1, 1897. be noticed that even now a tbrush will often have a note closely like aery of the tawny owl, or the evening cry of the partridge, or the prominent note of yet another species. Especially does it produce brief but loud whistles re- sembling those of the nuthatch. If persons who are blessed with a thrush in the garden will listen attentively to its song, they will perceive that while the first three months of the year are passing away their bird is extending its powers of variation and mimicry, so that the songs heard at the end of this period will be hardly comparable, as performances, with the primitive utterances of early January. The same feature of extended variation, but without mimicry, may be noticed in the blackbird, whicli sings in January short and simple strains, with a tendency to repeat them ; so that its songs then resemble not only those of a young blackbird commencing vocalization in October, but also those of its ally the missel-thrush. In fact, when both species begin to sing, their utterances are approxi- mately equal in barbaric simplicity as well as similar in tone ; but, while the blackbii-d progresses week by week towards the attainment of the long musical strains which form a sort of bass to the chorus of May, the missel-thrush seems to remain content with a repetition of two or three notes — very full, indeed, but hardly exceeding the interval of a third, and repeated many times with hardly a varia- tion at all. This bird is supposed to sing especially in stormy weather, and it sometimes does so ; but it sings most continuously in fine warm weather. In February it should be in full song. The rattling alarm of the blackbird is particularly noticeable in the first two months of the year, durmg which the bird betrays an increasing tendency to utter this remarkable strain on the slightest alarm, or when there is no alarm at all ; and then the cry — like the single clicking note so often repeated at evening — seems to be employed merely to make a fuss. The starling is, perhaps, the most persistent of all our singers, for the only time when it ceases to pour forth from our roofs its curious medley of original and bcrrowed notes is when the young leave the nest, from which period till August it is absent ; yet the noisy choruses of its assemblies in the fields prove that it sings while abroad as much as or more than at home. In the winter it often concludes its song with harsh squealing notes. These are uttered with increasing frequency as the season advances, and are often addressed to the mate. They are worth noticing. At morning and evening in December and January the chaffinch gives its cry, jiiik or tirik, sometimes with con- siderable frequency; but it never produces a continuous cry like the alarm of the blackbird or the long cry of the nuthatch. The bird has, nevertheless, a tendency to repeat this note rapidly, and the extent to which this prevails should be observed. In February the bird will begin to sing. Then also the greenfinch will begin to repeat its call-note for a song, both when on the wing and when perched; and towards the end of the month, or in March, the peculiar guttural song-note will be noticed. In these two months the flocks of linnets wiU sometimes be heard singing in a sort of chorus. In February we shall notice the song of the marsh titmouse. This has been described as resembling the words if he, but the best mode of suggesting the sound is by striking two notes alternately in the interval of a third, high on the piano — say, at an octave above G over the treble stave — and repeating them at the rate of about three couples per second. That gives a good idea of tlie song, which is obviously as simple as the common call of the cuckoo, and is repeated by the whole species, with wearying monotony. At the same period the pied wagtail will be heard singing a jumbled kind of song consisting of hardly any sounds except call-notes. In March the first warbler will arrive with cheery song. Besides the M[t-chaif', whence the bird is named, there is a cricket-hke chirp, which is given less often when the bird has first arrived than later in the season, when also it is sometimes varied in extent of repetition. Last mentioned and least necessary of our list, the house sparrow will be observed to immediately commence its seemingly noisy combats. The purpose of these assem- blies, which often consist of several males and one female, may be diflicult to determine ; but the cries employed at them appear to exhaust the vocabulary of the species. It will be noticed that the call-note of the male, chissick, though uttered hardly at all at the beginning of the year, occurs with increasiug frequency as the season advances. THE DECAY OF CLOUDS. By Dr. J. G. McPherson, F.R.S.E., late Mathematical Examiner in the Universitij of St. Andrew's. UNTIL Mr. John Aitken proved by experiment that cloud - particles are formed by the adhesion of water vapour to the dust-particles invisibly floating in the atmosphere, little was known about the real nature of clouds. The lowest stage in the formation of clouds is in the once little-understood pheno- menon of haze. The cleai-est air has some haze, and as the moisture increases the thickness of the air increases. In this case condensation takes place on dust-particles, even when the air is comparatively dry, before the tempera- ture comes down to the dew-point. The sultry haze, the suflbcating fogs, the drizzling mists, and the thin rain, as well as the great thunder rain and pelting hail, and the feathery snow, are now all known to be diflerent stages of the formation of the vapour in the air on the minute dust- particles at difl^erent grades of heat and cold. The forma- tion of clouds is now distinctly understood. But the attention of the meteorologist has not been so much directed to the decay of clouds. Now the processor decay in clouds takes place in various ways. A careful observer may discern the reverse process of the formation of clouds. In May (1896) my attention was particularly drawn to this in Strathmore, in Scotland. In the middle of that exceptionally sultry month I was arrested by a remarkable phenomenon. It was the hottest May for seventy-two years, and the dryest for many years. The whole parched earth was thirsting for rain. All the morning my eyes were turned to the clouds in the hope that the much-desired shower should fall. Till ten o'clock the sun was not seen, and there was no blue in the sky. Nor was there any haze or fog. The sky was full of clouds of varied thickness and form. But, suddenly, the sun shone through a thinner portion of a cloud, and to the north the sky began to open. In a quarter of an hour there was more blue to be seen than clouds. At the same time, near the horizon a haze was forming, gradually getting denser as time wore on. In an hour the whole clouds were gone, and the moisture returned to its thin air form. This was a pointed and rapid illustration of the decay from cloud form to haze, and then to the blue vapoury sky. It was an instance of the reverse process. As the sun cleared through, the temperature in the cloud-land rose, and evaporation took place on the surface of the cloud-particles, until by an untraceable but still a gradual process through fog the haze was formed. Even then the heat was too great for a definite haze, and the water vapour returned to the air. Januaky 1, 1897.] KNOWLEDGE 19 leaving the dust - particles in invisible suspension. Of I course, the water vapour was there ; otherwise I could not have seen in the sky the varied shades of blue, from the i horizon to the zenith, deepening as one looked upwards. Though this was a striking illustration on account of the particular temperature and drought, still it was only a practical instance of the theory of cloud decay thus indi- cated. Clouds decay in another way. Whenever a cloud is formed it begins to rain, and the drops shower down in immense numbers, though most minute in size. No doubt it is only in certain circumstances that these drops are attracted together so as to form large drops, which fall to the earth in genial showers to refresh the thirsty soil, or in a terrible deluge to cause great destruction. But when the temperature and pressure are not suitable for the for- mation of what we commonly know as rain, the line drops fall into the air under the cloud, where they immediately evaporate from their dust-free surfaces, if the air is dry and warm. AVhenever a cloud overhangs, fine rain is falling, so that the cloud is in the process of decay ; but this rain may not reach the earth on account of the dryness of the stratum of air beneath the cloud, and the heat of the air over the earth. So that on a summer day, with the gold- fringed fleecy clouds sailing overhead, it is really raining, but the drops, being very small, evaporate long before reaching the earth. It rains, but much of this melting of the clouds is reproduced by a wonderful circularity, the moisture evaporating, seizing other dust-particles in a cooler stratum, forming cloud-particles, falling again, and so on '"/ iiiiiiiitiiiii during the existing circumstances. That is the reason why surfaces may be exposed to a cloud on a mountain-side without being wetted. Radiant heat is the cause of the remarkable result. The rays of the sun, which strike the upper part of the cloud, not only heat that surface, but also penetrate the cloud and fall on the surface of bodies, generating heat there. These heated surfaces, again, radiate heat into the superincumbent air. This warm air receives the fine raindrops from the decaying cloud, and dissolves the moisture from the dust-particles before the moisture can reach the surfaces exposed. That a vast amount of radiant heat rushes through a cloud is clearly shown by exposing a thermometer with black bulb //( vm-wi. On some occasions a thermometer would indicate from forty degrees to fifty degrees above the temperature of the air, thus rendering the surface quite dry. Hence seats, walls, posts, etc., may be dry, though in the middle of a cloud which is gradually decaying. To the decay of clouds Mr. Aitken has lately been directing his attention. His observations, made in the clouds themselves, have shown that there is a difference of structure in clouds which are in the process of formation and those which are in the process of decay. In clouds in formation the water-particles are much smaller and far more numerous than in clouds in decay ; and, while the particles in clouds in decay are large enough to be seen with the unaided eye, when they fall on a properly lighted micrometer, they are so small in clouds in formation that, if the condensation is taking place rapidly, the particles cannot be seen without the aid of a lens of considerable magnifying power. The form of some clouds cannot be explained by the processes going on in the ordinary formation of clouds. We must look on the processes going on in decay for an explanation of these forms. Most authorities have made a wrong assumption as to the difi'erent shapes of clouds, as classified by Mr. Luke Howard in 1802, viz., the primary forms — cirrus, cumulus, and stratus; the intermediate — cirro-cumulus, cirro- atratus, and oumulo-atratus ; and the compound form, nimbus. They have assumed that these different shapes are in the process of formation, and that the whole explanation of the shapes taken by the clouds is founded on this supposition. Now, Mr. Aitken has pointed out that ripple-marked clouds, for instance, have been clouds of decay. It was generally understood that these ripple markings are due to the general movements of the air giving rise to a series of eddies, the axes of the eddies being horizontal and roughly parallel to each other. Now, according to Mr. Aitken, " it is very evident that the air revolving round these horizontal axes — that is, in a vertical plane — will at the lower part of its path be sub- jected to compression, and at the upper part to expansion. The natural result of this will evidently be, suppos-ing the air to be nearly saturated with moisture, a tendency for cloudy condensation to take place in the air at the upper part of its path, and it is this cloudy condensation in the upper part of the eddies that is supposed to produce the ripple-like cirrus, each ripple mark indicating the upper part of an eddy." Now, it is diflioult to imagine that the small amount of elevation and consequent expansion and cooling could give rise to so dense an amount of clouding as is generally observed, for any clouding produced in this way would likely be very thin and filmy. Accordingly another explanation must be given for the production of ripple -marked cirrus clouds, and that is in the decay of clouds. These are generally formed out of some cirro- stratus or similar cloud. When these are observed in fine weather it will be found that they frequently change to ripple-marked cii-rus in the process of decay to vanishing. The cirro-stratus gradually thins away till it attains such a depth that if there are any eddies at their level, the eddies break the cloud up into nearly parallel masses, the clear air being drawn in between the eddies. The eddies here do not produce the clouding, but break up the uniform cirro-stratus cloud into the ripple- marked cirrus. Mr. Aitken points out, in support of this theory, that lenticular cirrus clouds are fre- quently observed with ripple markings in one or more sides of them, just where the cloud is thin enough to be broken through by the eddies. The ripple marking? get nearer and nearer the centre as the cloud decays ; and at last, when nearly dissolved, these markings are extended quite across the cloud, in the peculiar " mackerel " appear- ance so gloriously seen on the 1st of November. Of course ripple clouds may be producad by formation, but this seems exceptional : and the decay theory is the more probable. Whether, then, we consider the cases of clouds gradually melting away back into their primil state of blue water vapour, or the constant fine raining from clouds and re-formation by evaporation without wetting any extended bodies on the surface of the earth, or the transformation of such clouds as the cirro-stratu? into the ripple cirrus, we are forced to the inevitable conclusion that in clouds there is not always develop- ment but sometimes degeneration ; not always formation, but sometimes decay. To this subject meteorologists must direct more attention. PROTECTED AND UNPROTECTED WARSHIPS. By Nautilus. THE comparative numbers and eSiciency of the pro- tected and unprotected battleships of the British Navy, and those of her rivals, have of late inspired much discussion among experts. The difference between a protected and an unprotected battleship consists in the first-named being fitted with a narrow belt 20 KNOWLEDGE. [Janhaky 1, 1897. of armour, about five feet wide, on her sides, in the wake of the water line, and her batteries and turrets are also armour-plated ; the last-named being without such protection. The most vulnerable part of a ship is that of her hull below the water line, for here are located the boilers, engines, magazines, and furnaces, on each of which the life, power, and movement of the vessel entirely depends. One shot, or one hundred, or even one thousand shots, might pass through the upper parts of a battleship without bringing about her destruction, or even without disabling her. What, then, is the need of such extravagant provision for protecting the upper works of a battleship by attempts to render them invulnerable, whilst the most vital under- water portion is left unprotected ? It has been proved beyond doubt that after the hundreds of millions of pounds sterling expended by our own and foreign Powers on the offensive and defensive merits of guns versus armour, thsy are no nearer a solution as to the superiority in the one case or the other than they were thirty years ago, and for many years past the idea of one ship destroying another by standing off and exchanging shots from a distance, has been recognized as an absolute impossibility. Lord Armstrong, on this point, has well stated that these stupendous warships " cannot be made inndnerable," and that their cost is so enormous that we cannot have a numerous Navy with such vessels. Whilst all the great naval Powers are busily engaged in bringing submarine warfare to a perfect system of attack by means of diving torpedo-boats, England has apparently neglected this means of marine attack. We hear of torpedo-boats, torpedo-boat catchers, and torpedo-boat destroyers, and we know that the so-called catchers are inferior in speed to the boats they are supposed to catch ; and as to the ''destroyers," their special destructive powers are not very apparent. It may very well be said that so far as these types are concerned, and also as regards first and second class battleships and cruisers, it is quite problematical as to which will destroy or be destroyed in a fair, above-board sea fight. The destroyers, attacking in large numbers under cover of darkness, owing to their speed and handiness, might by chance get a torpedo in contact with the side of an enemy. Then, of course, the battleship, devoid of underwater protection, would inevit- ably be destroyed. This result could not be achieved in broad daylight, as the light construction of the torpedo craft necessary for speed leaves them with very thin plating, averaging only about a quarter of an inch in thickness, that could be riddled through and through from the rapid discharge of quick-liring machine guns. The term " destroyer," in its fullest and truest sense, is only applicable to the modern diving torpedo-boat. So sure as one of these submarine ship destroyers, in a state of suspension at a regulated depth below the surface of the water, is navigated to within striking distance of a twenty-ton torpedo-launch, or a fifteen-thousand-ton battleship, so surely will that torpedo- launch or ponderous battleship be destroyed immediately on being struck by the missile aimed by her unseen sub- marine foe. There is no give-and-take about this what- ever, as the submarine torpedo-boat when deeply immersed is out of reach of its opponent, whilst at the same time it strikes at the most vital and unprotected part of the hull of the monster floating above it. Seeing that our battleships, as sea fortresses, form our first line of defence and our most powerful engine of offence, from an above-water point, and that all that practice could suggest, or that science could devise, has been provided for offensive or defensive operations either against land fortresses, hostile armour-clads, cruisers, torpedo-boats, or torpedoes, it is passing strange that our naval architects and marine engineers should have been so lax as to neglect to devise a form of protection against the scientific advances of submarine warfare. The following extracts from a report by C'apt. S. Eardley Wilmot, R.N., late chief torpedo expert of the Admiralty, respeating the defence of ships, will be read with interest ; — " The development of the ' Whitehead ' torpedo, with which now nearly all nations are supplied, renders the question of protecting ships against this attack one of the gravest consideration. " The torpedo of to-day travels at the rate of thirty knots an hour, and carries two hundred pounds of explosive com- pound directed against the most vulnerable part of a ship — that of her hull under water. " We have been enabled, by the addition of large masses of armour, to fairly protect the water line, and above it; against the eflects of artillery fire, but cannot extend this to the submerged portion of the hull as a defence against torpedo attack. We have, therefore, been obliged to restrict our endeavours, as far as structural arrangements are concerned, to give ships of war a double bottom, and subdividing them internally into a number of watertight compartments, thus seeking to diminish the effects of an explosion, and restrict the inflow of water to that point. " As, however, these arrangements could only give very partial protection at a time when torpedoes carried a com- paratively small charge, it was considered desirable to stop them before they could reach the ship, and for this purpose the present system of net defence was devised. " This consists of wire netting suspended vertically from steel or wooden booms attached to the hull of the ship, from which they project from twenty-five to thirty-five feet. The nets hang down to a depth of twenty feet, and are connected together in sections so as to then form a continuous crinoline of netting. " Being only suspended from the upper side, they hang loosely down and remain in this position when the ship is stationary. " But sho'Jd the ship move through the water, the nets are more or less impelled towards the surface, according to the speed of the ship. For these reasons naval officers do not consider nets can be used at sea. " Thus it is evident that if external protection is to be relied upon, it must be in a different form, and Dr. Jones has devised a torpedo guard which is not only novel, but free from most of the objections inherent to the net defence. His plan is to have steel shields made to the form of the ship, and ordinarily resting against the hull. They are, however, capable of being projected outwards when required to a distance of twenty feet from the hull, and this cushion of water, together with the resistance offered by the steel plating, should secure a ship from material injury in the event of a torpedo exploding against the guard. It is obvious that the plate could not be cut through like a net, nor would it be forced out of position by a current, or the ship moving through the water. " An advantage of this system is that all the appliances for working this protection are above the water line, and always in position, thus enabling the protection to be put in position at the shortest notice, while it overcomes the difliculty attached to supporting steel booms or rams if projected to a distance of twenty or thirty feet. " This plan now proposed by Dr. Jones is, in my opinion, the best which has yet been put forward for guarding against the terrible effects of locomotive torpedo attack ; January 1, 1897.] KNOWLEDGE. 21 and looking to the gi-ave issues involved, I consider that expenditure would be wisely incurred in giving it a thorough trial." The accompanying illustration is taken from a model showing one of Dr. Jones's modes of protection against torpedo attack. This illustration gives a foreshortened view taken off the port bow, and represents the vessel with the improved torpedo-guard expanded to its protective position. It is well known that the net system, which is the only one adopted by all countries, is at the same time universally condemned. A torpedo-guard of any practical utility would readily be preferred to the nets, and the guard shown in our illustration is a plausible means of defence. The value of Dr. Jones's torpedo defence for protecting our costly warships and our gallant seamen from the appalling dangers of torpedo attack, is emphasized by the approval before the eyes of our officials were opened to the fact of their now acknowledged universal supremacy. This fact should be an incentive to our naval rulers of to-day, and it should urge them not to repeat such a suicidal system of delay in the adoption of the latest and only known form of complete defence against torpedoes. ANIMAL LIFE IN ARCTIC REGIONS. By F. W. Headley, M.A. ON first thoughts it seems wonderful that there should be any life in regions near the North Pole; still more so that there should be large mammals living there, able to find food sufficient even in winter, when the thermometer sometimes sinks 90° below the freezing point. But the cold is not the only evil that they have to contend against. In the latitude in Model of Torpedo-boat with Uuard Opened. of the highest expert authorities in the United Kingdom. In the front rank of these is Sir E. J. Reed, K.C.B., well known as having designed and constructed warships for all the naval Powers of the world. The notorious and absurd delay accorded by our Govern- ment officials, both in the Army and Navy departments, to the adoption of the Whitehead torpedo and the Maxim gun (the two most destructive weapons of modern science for land and sea service) is lamentable to state, for tliey were in use for several years by the Continental Powers which Sir George Nares' expedition wintered, four hundred and fifty-three rnUes from the Pole, for one hundred and forty days the sun does not appear above the horizon — from October 13th to March 1st. It is true that they were not entirely without sunlight. On November 30th, at noon, the sky was so clear that the stars were hardly visible. On December 2'2ad there was an indistinct greenish tint at noon. On December 31st there was an increase in the duration and intensity of the twilight. On February 1st they were able to take considerable walks. KNOWLEDGE. [January 1, 1897. and by the middle of February, a fortnight before the reappearance of the sun, to go out shooting. It must be added that the moon shines very brightly in the clear air of the North, but, unfortunately, from November 19th till New Year's Day there is no moon. For more than forty days, therefore, there is nothing but starlight and a glimmer of sunlight at noon. Among the living things that'inhabit the Polar regions are not a few plants. Plants there must be if there is to be animal life, for animals cannot live on inorganic food. It is only that which gives plants their green colour, the chlorophyll, that can by a chemical process convert the radiant energy of sunlight into potential energy. And thus animals depend for their existence, directly or indirectly, on vegetables. Among the plants that thrive in these regions of great cold are a small saxifrage (Sarifraga oppnsitifdlia) — a low-growing plant with a handsome purple flower — dwarf willows a few inches high, dwarf birches, and the lichen called reindeer moss. These are, perhaps, the most important food plants, but there are many others that sometimes make a patch of ground gay in summer, such as the dwarf wallflower {Cheirantlms pygnuvus) and the yellow poppy. Dependent for life directly upon vegetables are the hares, the lemming, the musk ox, the reindeer. Those that prey upon these vegetable feeders are the ermine, the Arctic fox, and the wolf. There are, besides these, some that depend on the sea for their food — the seal, a fish-eater ; the Polar bear, that lives on seals, and in default of seals on vegetable food ; and the walrus, whose food consists of molluscs, etc. The lemming is a small rodent, its length about five inches, its ordinary colour a yellowish brown ; but during the Arctic winter, Colonel Feilden found that this turned to a greyish white. Its food is grass, Saxifnuia oppositi- folia, reindeer moss, and so forth. It makes galleries in the snow, and, apparently, the plants that it finds as it burrows are suflicient food for it. The Arctic hare in the extreme North is — at any rate, in many cases^white, not only in winter but the whole year round. It, too, feeds on the minute saxifrage mentioned above. The musk ox has long dark-brown hair, with a fine yellow far beneath. It is about the size of an ox of the Scotch breed, but in appearance is more like a long-haired sheep. Its teeth, too, resemble those of the sheep. Like sheep, too, the musk oxen form square to defend themselves when molested by dogs or hunters. Their chief food is the dwarf willow, and on this diet they manage to accumulate an enormous amount of fat in summer. In winter this becomes reduced, as we might expect. Besides man and the climate they have only one enemy, the wolf. They are found as far north as lat. 88°, and as far south as lat. 00°. The reindeer is familiar to everyone. It browses on the dwarf birch, on bilberry and crowberry bushes ; in winter time on reindeer moss, in autumn on seaweed. Brehm maintains that under stress of circumstances it will eat lemmings — not an impossi- bility, certainly, as red deer in Scotland have in hard winters been known to eat rabbits. We come now to the carnivores. The Arctic fox preys upon lemmings all the year round, and in the summer on birds. But sometimes he is found on islands where lemmings and all the smaller mammals are wanting. What, then, is there for him to live upon? He picks up dead seals, fish, molluscs, and crustaceans, and hopes for the return of the bu-ds with the spring-time. And some authorities believe that he stores food for the winter. * See the A ppendix to Mr. Trevor Battyc's book, " Icebound in Kolguer." The ermine is only a stoat whose coat has turned white with the coming of the snowtime. The process of change is this : the hairs that come at the time of the trans- formation are white, those already grown become blanched. And it has been found that cold :ilone will not produce the change, but that it comes with the snow, thus showing that natural selection has given to the northern stoat this wonderful means of protection. The Arctic hare, the Arctic fox, and to some extent the lemming in Arctic regions, change their dress to match the snow. Of all these Arctic animals none hibernate, with the possible exception of the Polar bear. The marmot, it is true, sleeps through the winter ; but though it is found well within the Arctic Cirnle in Eussia, yet it is not one of those that range very near the Pole. I have said little about the birds that in summer fly to the far North, and find countless bilberries and crowberries that have been preserved for them by the cold of the Arctic winter. Their habits are generally known. But this cannot be said of the fish that Baron Nordenskiold found in early spring in a lagoon in which the water had been frozen solid all the winter, and which had no outlet to the sea. How had they worn through the Arctic winter ? At Gape Hayes, lat. 76°, where the average temperature is four degrees below zero, and where snow falls in the height of summer. Colonel Feilden found a butterfly. In this icy climate how had it developed to the imago state ? There are problems about life in Arctic regions that are far from being settled yet. And much that we do know is full of wonder. Much information on this subject is to be found in various papers bv Colonel U. W. Feilden, wlio has clearly set forth all the problems involved and the facts which helji to solve them. See especially the ZoologUt for 1877, 1878, 1879, and the "Transactions of the Norfolk and Norwich Natur.alists' Society, 1886." THE FACE OF THE SKY FOR JANUARY. By Herbert Sadler, F.E.A.S. SUNSPOTS have not been very evident of late. Conveniently observable minima of Algol occur at 2h. 40m. a.m. on the 13th, at llh. 29m. p.m. on the 15th, at 8h. 18m. p.m. on the 18th, and at 5h. 7m. P.M. on the 21st. Mercury is practically invisible during the month in these latitudes. He is in inferior conjunction with the Sun on the 22nd. Venus is an evening star, and is now getting into a better position for observation, and becoming a very fine object in the western sky after sunset. On the 1st she sets at 7h. 45m. p.m., or about three and three-quarter hours after the Sun, with a southern declination (at noon) of 15° 19', and an apparent diameter of 16i", yV^hs of the disc being illuminated. On the 15th she sets at 3h. 20m. P.M., with a southern declination of 8° 52', and an apparent diameter of 18", VV'u''^^ °^ ^^^ ^^^'^ being illuminated. On the 31st she sets at 9h. 10m. p.m., or about four and a half hours after the Sun, with a southern declinatiou of 0° 40', and an apparent diameter of 20^", |';,ths of the disc being illuminated. During the month she describes a direct path through Aquarius into Pisces. Mars is an evening star, and is well situated foi observation. On the 1st he sets at 6h. 33m. a.m., and souths at Oh. 57m. p.m., with a northern declination of 25° 22', and an apparent diameter of 15-0 ', the phasis on the following limb amounting to J^". On the 11th he sets at 5h. 45m. a m., with a northern declination of 25° 12', and an apparent diameter of ISf. On the 21st ho sets at January 1, 1897.] KNOWLEDGE. 23 5h. 5m. A.M., with a norlhern declination of 25'^ 9 , and an apparent diameter of 12^'. On the 31st be sets at 41i. 32m. A.M., with a northern declination of 25° 14', and an apparent diameter of 11|", the phasis amounting to ~-,-j". He is stationary in Taurus on the 16th, and after that describes a short direct path in that constellation. •Jupiter is an evening star, and is now becoming well situated for observation. He rises on the 1st at 9h. 12m. P.M., with a northern declination of 8° 51', and an apparent equatorial diameter of 41 1 On the 11th he rises at 8h. BOm. P.M., with a northern declination of 9° 2', and an apparent equatorial diameter of 42|". On the 21st he rises at 8h. 80m. p.m., with a northern declination of 9 21', and an apparent equatorial diameter of 43". On the 31st he rises at 7h. 2m. p.m., with a northern declination of 9° 44', and an apparent equatorial diameter of 44^". During the month he describes a short retrograde path in Leo. Both Saturn and Uranus are, for the purposes of the amateur observer, invisible. Neptune is an evening star, rising on the 1st at 2h. 20m. p.m., with a northern declination of 21° 30', and an apparent diameter of 2-7". On the 31st he rises shortly after mid-day. He describes a very short retrograde path in Leo during the mouth. January is a favourable month for shooting stars, the most noted shower being that of the Quadrandtids, the radiant point being in E.A. 19h. 12qi., and 53' north declination, the greatest display being visible during the morning hours of January 1st to 3rd. The Moon is new at Oh. Bm. a.m. on the 3rd ; enters her first quarter at 6h. 46m. p.m. on the 10th ; is full at 8h. 17m. p.m. on the 18tli ; and enters her last quarter at 8h. 9m. p.m. on the 25th. By C. D. LooocK, B. A. Oxen. Communications for this column should be addressed to C. D. LococK, Burwash, Sussex, and posted on or before the 10th of each month. Solutions of December Problems. No. 1. (By J. T. Blakemore.) Key-move. — 1. Q to Ktsq. . . . K to K3, 2. Q to K4ch, etc. . . . K to B5, a. QxP, etc. ... K to Q5, 2. g to Kich, etc. . . . P to Q4, 2. Q to QKtO, etc. . . . Anything, 2. Q mates. No. 2. (By E. Henry.) 1. R to Esq, and mates next move. Solutions of both problems received - from C. Willis, Captain Forde, J. T. Blakemore, H. Le Jeune, H. F. Biggs, E. W. Brook. Of No. 2 only from W. Clugston, A. E. Whitehouse, J. E. Gore, A. P. Hyatt, A Norseman, J. M-Robert, Dr. Quilter. Of No. 1 only from L. Pfuugst (K — B5 variation incorrect). G. G. Beadi'ij and others.— U 1. R to B3, B to Q5ch. A. C. Tappemlen.— Atter 1. Q to Kt5ch, you have over- looked the defence P to Bl in some variations. ^ A. P. Hyatt— Aitei 1. Q to B2, P to Q4 ; 2. B xPcb, K to K3, there is no mate. It is a near try. If 1. 1. I. 1. 1. Correct Alpha, E. W. C?M^sfo».— Shall be glad to send one or two problems. Many thanks for the extracts. Tl'. /'. J. Kihcards. — Sec answer to G. G. Beazley and others. The game referred to is rather long for this column. (See Urithh Clu'sx Mayaune, September Number). T. Butty.— 1. Q to B2 is met by 1. ... P to Q4. In No. 2, If 1. R to B3, B to Q5ch, and there is no mate. J. T. Blakemore. — Many thanks for your prompt reply. Crt?!frti.— An abstract of your ingenious system is given on the nest page. Unfortunately we have no space for the whole. PROBLEMS. No. 1. By W. Clugston (Belfast). Black (;i). ■ t m mm. p p pTp ^'■'imr^^^'mS ■mm ^^ I^B White (fl). White mates in two moves. No. 2. By J. T. Blakemore. Black (10). White (11). White mates in three moves. We give below one of I\Ir. Pollock's best games. It was played in the Hastings International Tournament last year :— " French Defence." White. Biack. (W. H. K. Pollock.) (Dr. Tari-asch.) 1. P to K4 1. P to K3 2. P to K5 («) 2. P to KB3 3. P to Q4 - 3. P to QB4 4. B to Q3 (/-) 4. P to KB4 (r) 5. P to KKt4 ! 5. P X QP 6. P X P ■ C. (.) to R4ch 7. P to B3 7. OxKPch 8. Kt to K2 8. Kt to QB3 9. Castles {d) 9. B to B4 24 KNOWLEDGE. [January 1, 1897. 10. E to Ksq 10. Q to B3 11. Kt to Q2 11. KPxP(f) 12. PxP 12. B to K2 13. Kt to KB3 13. K to Qsq (/) 14. B to KKt5 14. Q toB2 15. BxBcb 15. KKt X B 16. QtoQ2 16. P to KE3 (r/) 17. Kt to K5 17. Kt X Kt 18. PxKt 18. P to QKtB 10. Kt to B4 19. B to Kt2 (/() 20. B to Kt5 20. Kt to B3 21. P to K6 21. Q to K2 (/) 22. Kt to Kt6 22. Q to Ktlch 23. Q X Qch 28. PxQ 24. KtxE 24. Kt to Q5 25. P to K7ch 25. Resigns. Notes, (a) Introduced by Steinitz in the Vienna Tournament of 1882. His idea originally was to exchange the advanced Pawn at once, and then by keeping pressure on the point at K.5 to rest the game on the confinement of Black's Queen's Bishop. Subsequently, however, he supported the Pawn instead. The first three moves on both sides follow the celebrated tie-game (Steinitz v. Winawer, June 23rd, 1882). (h) In the game referred to Steinitz played 4. PxP, B X P ; 5. QKt to B3. (c) Very weak. He should play 4. . . . BPxP, and if 5. Q to E5ch, K to K2. Black threatens then Q to R4cb (Steinitz). White's reply is excellent. ((/) Again good. White judiciously refrains from driving away the Queen from a spot where she is badly posted. ((') To prevent Kt to K4. But he would do better to make this move on his own account. ( /') Too slow. He cannot play 13. . . . P to Q4 be- cause of 14. Kt to B4 ; but he might try Kt to E3, or P to KE3, followed by P to KKt4. {//) Waste of time now. He should develop his QB at all hazards. In any case, having made the move, he should play 18. ... P to KKt4. (/() If now 19. ... P to KKt4, 20. P to K6 wins easily. (i) Q to Ksq was better ; but the game is lost in any case. Mr. Pollock played throughout with great skill and vigour. His final move threatens (if 25. ... K to Ksq) 26. BxPch! CHESS INTELLIGENCE. The score in the Lasker- Steinitz Match at Moscow is now — Lasker G, Steinitz 0, drawn 4. It is stated that M. Tchigorin intends to challenge Lasker, and that the latter will accept provided the stakes are high enough. The second Cable Match between England and America is fixed for February 12th and 13th, 1897. A preliminary tournament now in progress at the British Chess Club will help the committee in deciding on the constitution of the English team. The number of players on each side will this year be increased from eight to ten. We notice with regret the report of the death of Mr. A. C. Mackenzie, of Jamaica, one of the most successful problem composers of the day. His speciality was the three-move direct mate, and ho took an extraordinary number of prizes in international tournaments for this class of composition. Mr. Mackenzie was chess editor of the Jamaica Wackhj Gleaner, and the author of " Chess : its Prose and Poetry." A correspondent sends an ingenious mnemonic device for application to games or problems. His method is as follows ; — He designates the King K, the Queen Q or L, the Eook R or M, the Bishop B or N, the Knight O, and the Pawn P. The files are denoted, as in the German notation, by the letters a, b, c, d, e, f, g, h. But the ranks, instead of 1, 2. . . . 8, are denoted by o, tw, th, fo, fi, si, se, e. Thus 1. P to K4, becomes Pe fo, while 2. Q to E5 would be L (or Q) h ti. The possessor of a bad memory for chess (but a good one for poetry) now selects any poem with which he is familiar, and proceeds to associate the moves of a game, reduced to his private notation, with the lines, or, at least, the spirit, of the poem. An extract from a game sent by our correspondent, and associated with Goldsmith's " Elegy on the Death of a Mad Dog," will explain the method — 11. 12. Kt to Qo Q to Qsq PxP BxP O d fi _ ()ne '/octory/nding L d e ~ Life (in) (/anger (?xclaimed — P t. P _ Paris ! to Pasteur ! NTP ~ iVevertheless take (a) Pill." Problems may be adapted in the same way. For instance, a problem in which the White King is at K2 and the Queen at Q2 associates itself naturally with " 0 Lady, twine no wreath for me " ; c.//., " Lady, don't twine ; kindly eschew twine." Perhaps some of our readers might care to construct these mnemonic devices, though, practically, most would find it easier to learn a game by heart than to adapt it to a poem and commit the adaptation to memory. KNOWLEDGE, PUBLISHED MONTHLY. Contents of No. 134. PAQE Forecasting Famines in India. By Donglas Archibald 265 Greek Vases. — IV. C. — Red- Fi;?ured Vases (Finest Pei'iod.) By 11. B. Walters, M.A., F.S.A. (/Iliisfralfd) 26" Some Curious Facts in Plant Distribution.— VI. By W. Hot- ting Hemsley, F.E.S 270 Our Fur Producers. — VI, Ro- dents, Uni^nlates, and Mar- supials. By R. Lydekker, B,A., F.R.S. (liiustrated) 271 Letters:— W. H. S. Monck ; E. Brown ; E. E. Markwick ; David Flauery; J. M. Wadinore: C. Robinson ; A Spiderman; Clias. A, Schott 275 Notices of Books 277 A Possible Cause of Change on the Moon's Surface. By Charles Davison, Sc.D., F.G.S The Lunar Metropolis. -Bv E. Walter Maunder, F.E.A.S. {IUti.!.tratfd) Science Notes Waves.— XII. Earthquakes, the Pulse, Nerve Waves, and Tele- patliv. Bv Vaughan Cornish, M.Sc. (niiLslrated) The Beech. By George Paxton. (Blitstrated) Helium and Parhelium. By E. Walter Maunder, F.R.A.S. {lUustraUd) The Faceof tile Sky forNoyember. By Herbert Sadler. F.R.A.S. ... Chess Column. By C. D. Locock, B.A.Oxon 278 279 280 281 282 2St 287 287 Two Plates. — 1. Greek Vases. 2. The Lunar Metropolis. NOTICES. Bound volumes of Knowledge, New Series, can be supplied as follows ; — Vols. I.. II.. III., and VIII., 10a. 6d. each ; Vols. VI., VII., IX., X, and XI. (189)!), 8s. 6d. each. Binding Cases, Is. 6d. each ; post free, la. 9d, Subscribers' numbers bound (including case and Index), 2s. 6d. each volume. Index of Articles and lUuatrations for 1891, 1892, 1894, 1895, and 1896 oan be supphed for 3d. each. TERMS OF SUBSCRIPTION, Annual Subscription, Ss., Post Febe. •• Knowledge" as a Monthly Magazine cannot be registered as a Newspaper for transmission abroad. The terms of Subaoi-iption per annum are therefore as follows : — To any address in the United Kingdom, the Continent, Canada, United States, Egypt, India, and other places in the Postal Union, the Subscription is 8 ahillinga, including postage; or 2 dollars; or 8 marks; or 10 francs. For all places outside the Postal Union, 6 shillings in addition to the postage Commimications for the Editors and Books for Review should be addi-essed Editors, " Knowledoe," 326, High Holbom, London, W.C. OUR BOOK TABLE. IT is, perhaps, superfluous to draw the attention of readers of Kxowledge to the fact that the output of the press is, year by year, an increasing quantity — an increase or progression more alsin to the geometrical function than the arithmetical. At the present moment we ourselves are particularly impressed with the fact, because a great number of books are still heaped up on our table, waiting to be reviewed, and this in face of the fact that we have so far exerted ourselves as to issue a special supplement in order to begin the new year with a conscience void of offence in this matter. On the top of the heap is a volume labelled " Differential and Integral Calculus," a title, by the way, which, both orally and visually, strikes one as being no mere empty phrase ; but the one thing it recalls to us on the instant is that " necessity is the mother of invention." Newton, the greatest philosopher and mathematician of modern times, felt the need of some means of dealing with the limiting values of the ratios of small quantities in exact physical science, and his inventive faculty evolved the method of ihtxions. It is therefore two hundred years since the progenitors of this class of books were first launched into the world, and now the number of such books is legion. The next book is a little treatise on the X rays. There are already many books on this subject, which is truly marvellous in its revelations of the heretofore impenetrable recesses of the living animal organization ; but the fascination with which it has held the popular mind seems to have been inspired chiefly by a morbid curiosity — a curiosity the gratification of which certain enterprising individuals have not been slow in recognizing as a short cut to wealth. Prof. Eontgen's discovery, however, affords an excellent illustration as to the way in which scientific literature is propagated. During the short period which has elapsed since Eontgen first enunciated his achieve- ments in this new departure, hundreds of ephemeral articles have appeared in the papers. In the same way, by other books, we are reminded of the drastic changes and new developments in scientific literature by the introduction of the conservation of energy and the correlation of forces. It is to such men as the late James Prescott Joule that the fountain head of a very large portion of the deluge of modern literatiure may be traced. The investigations of these men have taught us that to do work is merely to transform energy; that whatever process is employed to change the form of matter, it cannot change the total quantity of matter ; that the total quantity of electricity — which may, of course, be transformed into energy so as to do work — in the universe is invariable, its distribution alone varying. But why multiply instances of this kind ? Indeed, the pressure on our available space forbids further dilation in this direction. It is, however, plain that scientific books, like rivers in the drainage system of a country, have, comparatively speaking, a few main sources and an immense number of tributaries which flow into and swell the principal streams. While the great mass of books drop from the press still- born, and many others are mere compilations for specific purposes, and often produced without any claims to ability on the part of their authors, but solely on account of the prestige of their position, it is quite impossible to estimate the influence exercised on the world by such books as Adam Smith's "Inquiry into the Nature and Causes of the Wealth of Nations,'' which established the law of supply and demand— made labour, not land or precious metals, the source of wealth. In a word, Smith's writings laid the foundation of political economy. And what is the fate of this great product of the press ? Is there a demand equal to the supply, and if so, how ? To answer these questions satisfactorily would be to trace the history of education during the Victorian era. In 1837 two-thirds of the working population of England were unable to read and write, and those who did possess acquisitions of this kind knew nothing of science. Previous to 1839 the poor received their education mainly in Simday schools, but in that year, in spite of much opposi- tion from the upper classes, a little State aid was first given to lift the masses above the mists of intellectual gloom. Working from five in the morning till seven or eight at night, what opportunity, or even inclination, could there be for intellectual employments among the workers ? A little space, in early years, was afl'orded chiefly by the generosity of private indinduals for acquiring the rudiments of education, but it has been said that the teachers were generally persons who were either unfit for anything else, or who could find no other means of obtaining a hving. Books, to be of any use, must be read, and ignorance therefore does not lend itself to their distribution. _ In these days, however, of State-aided schools, technical institutions, and free libraries distributed all over the country like parish churches, there is, perhaps, not one individual in twenty who is unable to read, and there is, moreover, a large proportion of the people who cull their chief pleasures in life from books. Education has also enabled people to recognize in it a lever, and in many cases the only lever, which can raise them in the social scale. And so it is that the book producers have in these latter days a constituency to cater for which resembles that in former years in a way comparable to that which obtains between the acorn and the oak ; and the vast avalanche of books which, taken collectively, are enough to overwhelm any single individual, are after all only commensurate with the increased demand — an index of the progi'ess of tlie nation. 20 KNOWLEDGE [Januaby 1, 1897. REVIEWS OF BOOKS. Himphn/ Davy, Poel and Philosopher. By T. E. Thorpe, LL.D., F.K.S. (The Century Science Series. Cassell & Co.) 8s. 6d. This is one of the very best short biographies that we ever remember to have read. Prof. Thorpe is well known in the scientific world as possessing a singularly clear and attractive style of writing, and we may say with confidence that this gift has never been shown to greater advantage than in the little volume now before us. The book is based for the most part on the well-known memoirs of Davy by Dr. Paris and Dr. John Davy, especially upon that of the latter ; and in his preface the author specifies in detail the further sources from which he drew his information. From the variety and extent of this list of references it is easy to infer that no pains have been spared, and — to put it shortly — the impression left upon Institution as it was in Davy's time, a drawing which tells its own moral in these days of elaborate apparatus and fittings. In nothing was Davy's genius more clearly shown than in the precision with which he almost intui- tively seized upon the true lines of a research — upon the analogy of iodine to chlorine in the case just mentioned. And lest anyone should imagine from what has just been said that his work was hasty and incomplete, let him but read Davy's classical papers on chlorine, and marvel at the closeness and accuracy of reasoning which they exhibit. An interesting account is given of the safety lamp, together with drawings of the various forms of lamps which Davy tried before he arrived at the one we all know so well ; while a portion of the concluding chapter is devoted to )avy's presidency of the Pioyal Society. The book is lightened up by pleasant side-touches, such as the des- cription given byLockhart in his " Life of Scott " of that famous night during one of Davy's visits to Abbotsford, including the remark which it drew from honest William Laidlaw. Space will not permit of a reference here to Davy's real poetic power. That he was a great chemical genius, and that his work was of immense benefit to mankind at large, everyone will allow. And.ifhepermittedhisambition for scientific fame to acquire an undue influence over him, let us rather turn aside from that and dwell on some of his many good qualities, such as the disinterestedness he showed wherever money was concerned, and the unchanging love and affection which throughout his life he bore to his mother and the other members of his family. Pueumatic Experiment at the Koyal Institution. (From " Humphry Davy, Poet and Pliilosoph the mind after reading the book is that the author has given us an impartial and unbiased, but at the same time a sympathetic, account of the great chemical philosopher. The rapid, almost meteoric, rise of Davy was of course one of the most striking points in his career. He was but twenty-one years of age when he left the Pneumatic Insti- tution at Bristol for the Iloyal Institution, and barely twenty-nine when he reached the summit of his scientific fame by the isolation of the metals of the alkalies. Another characteristic was the marvellous rate at which he got through his investigations ; thus, in the spare time of a fortnight spent in Paris, in 1813, he worked out the broad outlines of the chemistry of iodine, partly in Chevreul's laboratory and partly in his hotel with the aid of the chemical apparatus which he was in the habit of carrying about with him on his travels. Not the least interesting thing in the book, by the way, is the illustra- tion on page 91 of the chemical laboratory of the Koyal (After Gillray.) er.''J Biological Experimentation : its Functions and Limits. By Sir Benjamin Ward Eichardson, M.D., F.R.S. (George Bell & Sons.) 2s. Gd. No fairer statement on the subject of experimentation on living animals could be made than that contained in this little volume. The crux of the matter appears to be whether in learning the art of prevention it is requisite to produce pain, and, if so, whether the results justify the means. The general conclusions to which Sir Benjamin Ward Eichardson appears to arrive are that painful experiment may be expedient but is not indispensable ; that experiment on animals played no indispensable part in the discovery of either general or local anaesthesia ; that they should only be performed for a definite object, should not be made a matter of demonstration to students in schools of physiology, and should bo conducted, as far as possible, painlessly. Vivisectionists and anti-vivisectionista would be brought to view their differences in a better state of mind by reading this testimony of an investigator capable of taking a broad survey of a difficult subject and of giving an honest opinion. Januabt 1, 1897.] KNOWLEDGE 27 Prehistoric Man and Beast. By Rev. Ji. N. Hutchinson, B.A., F.G.S. With Illustrations by CecO Aldin. (Smith, Elder, & Co.). lOs. 6d. The author of this book is favourably known to readers of popular scientific literature as a lucid interpreter of the language of specialists, and one who can put life into the dry bones of science. He has in previous volumes traced the course of development of animal life upon the earth, and now naturally crowns his work with the story of our prehistoric ancestors, constructing from the outline sketched by geologists and ar- chaeologists a striking picture of living men and conditions as they once existed. To his literary products may thus very appropriately be applied the words of the late Poet Laureate : — First the monster, then the man : Tattooed or woaded, winter clad in skins Raw from the prime, and crushing down his mate; As yet we find in barbarous isles, and here Among the lowest. The present work is in every respect worthy of the author. It com- bines graphic description with scientific accuracy, and is an admirable ex- ample of what a j udicious use of the imagination can achieve upon a basis of established facts. Even in this epoch of rush and bustle, many people find interest in reading about the early history of mankind, and a number of excellent works have been pub- lished upon this subject. Nevertheless, there is ample room for the vol- ume before us, and we have no doubt Mr. Hutchinson's latest con- tribution to the literature of general readers will meet with the recognition it deserves. If it succeeds in increasing the interest in prehistoric man and remains, it may add to the number of workers m anthropology, so that eventually the Anthro- pological Institute, instead of being one of the smallest of the British learned societies, would become the greatest of them all. chapter of Genesis as to a science primer, but rather regard it as a grand poetical account of the origin of things, containing primitive interpretations of natural appearances accommodated to the high type of religion of the .Jewish people. The view that " the word ' day ' may be understood to mean any period of time," in the Hebrew record of creation, is another vestige of the period when forced interpreta- tions were put upon a majestic narrative in order to adapt the Bib- lical cosmogony to the facts of modern science. A large part of the chapter on "The An- tiquity of Man" is taken up with a description of the theory that the signs of the zodiac originated in Egypt, and that their designations are derived from the phenomena of the seasons in the Nile Valley. Here and there Mr. Hutchinson ap- parently confuses the signs with the constel- lations of the zodiac, the result being conclusious of very doubtful quality. The sign Leo probably owes its name to the ap- pearance of lions on the borders of the Nile when the sun entered, or was in the middle of, one of the twelve equal spaces into which the ecliptic was divided for conve- nience. The sizes of the constellations could not, we think, have anything to do with the names given to the signs, and certainly not in the way suggested on page 138. The views of Sir Henry Howorth (who contri- butes a preface to the book) on glacial periods and the causes of them, find expression and sup- port in the two chapters on "The Myth of the Great Ice Age and Theories of the Flood," and " Changes of Climate their Causes." In stars of the Mira due to eclipses by The Warrior's Courtship, Denmark. All the Clothing, Weapons, Ornaments, taken from Actual DiscoTeries in the Peat of Denmark. Bronze Age. {Ffom " Preliistoric Man and Be.ist.'') and the latter chapter the variability of Ceti type is erroneously said to be dark bodies revolving roimd them. Other chapters deal with rude stone monuments, abodes of the living and dead, the " little folk," or fairies and mermen, and ancient cave-dwellers. The ten full-page illustrations have some hfe in them, though one or two are rather comical ; the frontispiece, representing a cave bear, sabre-toothed tiger, and a hyffina, together at the entrance of a cave occupied by a man of the Stone Age, being avowedly an incongruous picture. Attractive as the volume is, there are a few minor points which invite criticism. In the introduction the view is favoured that the account of creation in the opening chapters of Genesis implies evolution. This was the opmion about twenty years ago, but we believe the fore- most thinkers in the Church to-day do not go to the first 28 KNOWLEDGE [January 1, 1897. Autobiof/raphy of Sir George Biddell Ain/, K.C.B., M.A., LL.D., b.C.L., F.n.S., F.B.A.S. Edited by WUfred Airy, B.A., M. Inst. C.E. (Cambridge University Press.) This is a disappointing book. Tliose who knew Sir George Airy, and were aware of his strongly- marked character, scientific eminence, and diversified public service, would naturally expect that his biography would be one of deep interest. It may seem ungracious to criticize so strongly a son's tribute to his father, but we fear that the verdict on the book of the general reader will be that it is " deadly dull." Those, alone, will find it interesting who, having known Airy himself, or who, having been brought into close connexion with his work, can clothe the " dry bones " of mere catalogues of papers, meetings, and journeys with living memories of the man, or with associations with the Eoyal Observatory, on which he stamped so vividly his own personality. It is easy to explain how this undesirable effect has been produced. The book consists for the most part of clippings from Airy's diary — that is to say, from the memorandum book of a most methodical business man— and from his annual reports to the Board of Visitors, with but very little explanatory or connecting remarks by the editor. The annual reports are, of course, as dull as official reports usually are, and such systematic quotation might well have been spared us, as the reports themselves are readily accessible to the student. The notes of private history are even less satisfying, and run generally in some such fashion as this : — " I was at Playford for a large part of January. On March 26th I went to Beading to visit Mr. Sheepshanks, and afterwards to Silchester and Hereford. On June 21st I went with my wife and two eldest sons to Edinburgh and other places in Scotland, but residing principally at Oban, where I hired a house." The chief relief to this dry catalogue is afforded by the admirable and discriminating " personal sketch " of his father which Mr. Wilfred Airy has given in the first chapter, and by the letters of Sir George which are scat- tered far too sparingly throughout the book. A complete list of all his books and papers is given in the appendix, which makes one the more inclined to grudge the space occupied by mere references to them in the body of the work. The result of the method adopted is that the book is in no true sense a biography or an autobiography of Sir George Airy. It exhibits but only a portion of his chara3- ter, and that by no means always the most pleasing. It shows him to be a strong, egotistical, self-centred man. His son speaks of him as " invulnerable to hero-worship "; the book suggests that this was because outside worshippers could not excel him in his keen appreciation of his own merits. This, however, is mostly due to what we must hold to be the unfortunate form in which the book is cast, for Airy, though by no means prone to self-depreciation, could register his mistakes and failures with great im- partiality. His greatest mistake, however, escaped him. This was that devotion to system and detail which he carried to a disastrous excess. The result was, that for the forty-six years during which he directed Greenwich Observatory, a fatal proportion of his time and powers was devoted to purely mechanical and routine work. And yet the work Airy did was stupendous, both in value and amount, and by no means in astronomy alone ; and this the book brings home to us with clearness and preci- sion. As a storehouse of dates and facts relating to the progress of science during the sixty years that followed his taking his degree at Cambridge, it will be invaluable to the student. TJie Student's Handbook of British Mosses. By H. N. Dixon, M.A., F.L.S. With Illustrations and Key to the Genera and Species by H. G. Jameson, M.A. (Wheldon & Co.) 183. 6d. This practical handbook ought to be in the possession of everyone taking up the study of the mosses of our islands. Hitherto there has been really no work which supplied the needs of bryological collectors and students within comparatively modest dimensions. No question can, therefore, be raised as to the opening for a volume such as that under notice. The work begins with a brief introduction, following which come a glossary, a key to the genera, systematic descriptions of the orders, genera, and species ; a good index, with synonyms ; and sixty full-page plates, each representing characteristic structures of ten or twelve species. All the information required to identify and thence to classify mosses is thus contained in the book, and it is presented in a form which renders identification comparatively easy. The book needs no further recommendation to the notice of students. Cock Lane and Common Sense. By Andrew Lang. New Edition. (Longmans, Green, & Co.) 83. 6d. There is such an enormous mass of fraud and trickery carried on under the name of spiritualism that no wonder the great majority of scientific men stand aloof from the subject. Dr. A. E. Wallace, Mr. Crookes, and Prof. Oliver Lodge have devoted their attention to psychical manifestations ; but the chief conclusion to which their testimonies lead, in many cases, is that the investigation of material things does not necessarily endow men with the ability to discover deception. But if there is a solid nucleus of truth amidst the mass of falsehood classified as spiritualistic phenomena, it is worth investigation, for every undiscovered fact is a reproach to science. Mr. Andrew Lang urges that such matters as wraiths, ghosts, corpse-candles, crystal-gazing, haunted houses, fire-walking, and all the other branches of " spookism " deserve to be studied, not so much because a grain of reality might be found in them as because of their anthropological bearings. Such things are recorded and compared by folk-lorists and anthropologists so long as they are part of vague rural tradition or savage belief, but when the evidence is furnished by civilized people little interest is taken in it. This position certainly does not seem logical, and what Mr. Lang endeavours to do in the present volume is to reconcile anthropology and folk-lore with psychical research. Respectable evidence exists as to the occurrence of abnormal physical phenomena ; and though the facts may be the result of conjuring, and of more or less hallucinatory experience, they are, Mr. Lang holds, none the less proper subjects of anthropological inquiry. But whether this is conceded or not, and whether the reader is interested in the object in view or merely in accounts of more or less inexplicable experiences, he will derive pleasure from the perusal of " Cock Lane and Common Sense." Mr. W. Trueman Tucker, F.G.S., has issued in pamphlet form a paper read by him before the Leicester Literary and Philosophical Society. The paper is an account of " Some Supposed British Remains from Rothley, Leicester." These remains consist of human skeletons (some cremated) found in shallow graves, pottery, bronze gilt fibula, coins, keys, a wooden image, and stone grinding miUs. The pamphlet is illustrated with photographs of several of the objects found. The author suggests that these remains are of Ancient British origin, but the evidence is slender, and needs confirmation. Januaby 1, 1897.] KNOWLEDGE 29 Joseph Thomson, African Explorer. By J. B. Thomson. (Low, Marston, .^- Co.) Illustrated. 7s. Gd. Among the roll of African explorers there is no name more revered than that of the brilliant young scientist, -Joseph Thomson, ■who, alas! passed over to the great majority only too soon. The volume under consideration is a biographical sketch, together with a rrsumeoi the expeditions which this worthy follower in the footsteps of such men as Park, Bruce, Moffat, and Livingstone, led into hitherto unknown regions of the Dark Continent. The reading of his exploits among the savage tribes of the interior, and sometimes amid the semi-bar- baric splendours of powerful states — travelling through lands blasted and barren, where, through the quiver- ing heat-haze, every- thing is seen with a spectral glamour upon it ; wearily tramping for days at one time over great waterless plains, and at another through vast swamps up to the knees in mud :| now engaged in a life-and-death struggle with fever; at another time brought to death's door by misadven- ture with wild beasts ; and ever carrying life in one's hands, so to speak, among the aggres- sive and ferocious warriors : all this reads with as much interest as the exploits of any fabled knight of chivalry in his quest for the Holy Grail. But Thomson's career was some- thing more than a series of Quixotic adventures. He not only pioneered the way into unknown lands and opened up a highway for the worshippers of Mammon, but he also made valuable science. He brought with him from Atlas Moiintains, Tanganyika Basin, etc tions of the fauna and flora geologist himself, he was of the formations in Tlie Reliquary and Illustrated Archaologist. Vol IL (Bcmrose.) Illustrated. 123. Those whose delight it is to contemplate the conditions of life in bygone ages as it is revealed to the keenly imaginative mind by all manner of interesting objects gathered from diverse sources, and, as regards age, extending backwards into hoary antiquity, will do well to interest themselves in this periodical — a quarterly journal and review. Here " Old Mortality" will find abundant material to satiate the cravings of the most romantic, and the arm-chair antiquary may study excellent presentments of such objects at his own fireside. The Gate House of (From "The contributions to Masailand, the , valuable collec- and, being an accomplished able to render an account the lands which he traversed. But it is fortunate for the reading public that the compiling of these pages should have been entrusted to the care of the Eev. J. B. Thomson, brother of the explorer, for he has a most facile pen, picturesque imagination, and consummate skill in bringing into prominence the humorous as well as the pathetic aspects of the explorer's life. The Society for the Protection of Birds is now issuing a very useful series of educational leaf- lets. These leaflets are edited by H. E. Dresser, FIl.S., F.Z.S., and are written for the most part by well-known ornithologists. Two have already been published, one on owls, the other on woodpeckers, and we understand that a number more will be published very shortly. Taking the owl as an example, we find the following points clearly and briefly set out : — Names of owls found in the British Isles ; description of each ; where, when, and in what numbers found ; food , characteristics , protection, and a few remarks on general habits. The plan is excellent, and the leaflets are certain to spread a know- ledge of our birds. In an educational series like this, how- ever, the utmost care should be taken to have every detail correct, and these leaflets have not been very carefully revised. For instance, we are surprised to read that the tawny owl [Symium uluco) is a constant resident in Ireland, when we know that it has never yet been found there. Again, we are told that aU three species of woodpecker " are resident throughout the British Islands, but rare in the North of England, Scotland, and Ireland." Since the green woodpecker has only twice been found in Ireland, and the spotted woodpecker (Dendrocopus major) has never been known to breed there, the statement that all the three woodpeckers are reaident in the British Islands is ob- viously incorrect. In fact, the descriptions of the range of the birds are altogether loose and require careful revision. lliornton Abbey. Eelifiuiu'y.") 30 KNOWLEDGE. [January 1, 1897. The Evolution of Bird Song. By Charles A. Witchell. (A. ct C. Black.) 5s. For the last ten years or more Mr. Witchell has been studymg bird song, and the present book is the result of his work. We must at the outset heartily congratulate and thank the author for this very valuable addition to ornithological literature. The facts related in the book before us could only have been collected by one who was a keen observer and withal a skilled musician, and we are sure that a number of the author's observations will be new to most ornithologists, and will delight them and all who are interested in our birds. Mr. Witchell puts forward a number of theories in relation to the origin and evolution of bird song. Some of these are plausible enough, and most deserve consideration. We think, how- ever, that the author has overstepped the bounds of com- mon sense in some instances, as, for example, when he leads us to infer that the origin of the landrail's " creaking" note is the imitation of the soimd produced by cattle feeding. Some very startling facts concerning the power of mimicry in certain birds are brought out at the end of Chapter IX. For instance, about seventy thrushes under observation were heard, in all, to imitate the songs or call notes of no fewer than twenty-nine different species of birds. The robin, skylark, starling, sedge warbler, and other birds appear also to mimic to a surprising degree. A>'e have all noticed, on occasions, marked instances of mimicry in the notes of different birds, but the imitations here described are often imperfect and mingled with the bird's usual song. The detection of this class of imitation is by no means within the reach of all : it requires a listener who possesses, besides a very accurate and retentive memory for sounds, a trained ear. The last chapter in the book is devoted to the music of bird song, and an appendix is added containing several songs written in musical notation. Altogether Mr. Witchell's book is of great value, for very little has been written of the songs of buds, and never before has the subject been treated in such an exhaustive and masterly fashion. Physies for Students of Medicine. By Alfred Daniell, M.A., LL.B., D.Sc. (Macm'dlan.) Illustrated. 4s. 6d. Partly through the pioneer work of Dr. Daniell in the Edinburgh School of Jlediciue, physics is now part of the extended course of professional study regulated by the General Medical Council. The recognition of the subject was an act of wisdom, for physics is the only sound foundation for scientific knowledge, and is as essential to students of medicine as to students of engineering. To provide the former class with a manual on physical principles, with special reference to the applications of these principles met with in medical science, this book has been written. The result is a fairly satisfactory course of general physics — rather diffuse, perhaps, in parts, but one which will interest and be of service to every practitioner, and which every medical student would do well to follow, if he can find time. How very helpful a knowledge of physics is to medical men may be gathered fi-om the work that has been done this year in Rontgen photography. Practitioners with such a foundation have been able to apply at once their knowledge, while those who are deficient in that regard are mourning that the subject was not included in their studies. Many other instances might be cited, but we believe it is now generally agreed that physics should form part of the professional curriculum ; and if there be any who doubt whether its bearings upon medicine are real, they have only to glance through this book to be convinced of their error. One blemish, to which attention mast be drawn, is the absence of an index. Te.vt Book of Zoology. By Dr. J. E. V. Boas. Trans- lated by J. W. Kirkaldy and E. C. Pollard, B.Sc. (Sampson Low). Illustrated. This is an English trans- lation of a work which has appeared in two Danish and two German editions. It is intended primarily to assist beginners in the study of zoology. The book is divided into a general part, treating of the structure and history of animals as a whole, and a special part, treating of the anatomy and shortly of the habits of different orders of animals. Lists are also added of the more important forms of the fauna of the British Isles. The anatomical portions of the book are excellent and well helped out by the numerous illustrations. A glossary of the scientific terms used would, however, have been a valuable addition for the beginner. It would have been better, we think, to have left out the lists of fauna, since they are incomplete. Creatures rare in this country have a place in the lists while others more common are left out, and the lists are thus of very little value. The short reviews of the habits of the animals are also by no means valuable, since they are not altogether correct. For instance, we notice several incorrect statements with regard to the migration of birds. For these reasons we can only recommend the book as an excellent and valuable treatise on zoological anatomy. Left Half of Skull of Bua Constriftor. (From "Text Book of Zoolog-j-.") A DictioiKiry of Chcinical SDlubilities, Inorijanic. By Arthur Messinger Comey, Ph.D. (Macmillan.) 1.3s. A chemical library will now not be complete without this monumental work on the solubility of chemical substances, and every practical chemist should endeavour to obtain it. The labour involved in the production of such a dictionary, containing data obtained by investigators in many parts of the world, must have been immense. All analyzed inorganic substances are included, the solubility in water being first given, then the specific gravities of the aqueous solutions, and the boiling-points, and, following this, the solubility of the substance in other solvents. The arrange- ment of chemical compounds in alphabetical order was a difficult task, but an intelligent plan has been followed, and cross references are used to obviate to some extent the confusion arising from the want of uniformity in chemical nomenclature. Chemists are thus provided with a volume capable of furnishing them with the results of all important researches on solubility, arranged in a form for ready reference. The great disparity among the sub- stances with which the chemist has to deal, as regards the amount any solvent will take up, is a matter altogether too much for the memory, and it strikes us that students generally, and analytical chemists in particular, will heartUy welcome the volume ; and we trust that it will meet with that best evidence of appreciation — a large circulation. January 1, 1897.] KNOWLEDGE Bl Diagrams of Terrestrial and Astronomical Objects and Phenomena. By E. A. Gregory, F.R.A.S. (Chapman & Hall.) 21g. net. These sheets, twelve in number, and forty inches by thirty inches in size, are intended as aids to lecturers on that comprehensive subject, physio- graphy. Hence it is that a very diverse collection of the most striking terrestrial and astronomical phenomena which cannot be experimentally demonstrated or easily observed, are figured. Each chart contains several figures which are grouped under appropriate headings, such as — Form and Rotation of the Earth ; The Sun's Family of Planets ; Eclipses of the Sun and Moon ; Isotherms and Isobars ; The Sea and Circulation of Water ; Volcanoes and Earthquakes ; Peat, Coal, and Coral. Great discre- tion has been exercised in the choice of sub- jects, and the author's claim to praise in this direction is further em- phasized by the pains he has taken to select