2.s6 



NA TURE 



[7n/y 25. 187: 



IL is now some years since I carried out, in the case of Iceland 

 spar, the method of examinalion of the law of refraction which I 

 described in my report on Double Refraction, published in the 

 Report of the British Association for the year 1S62. A piisni, 

 approximately right-angled isosceles, was cut in such a direction 

 as to admit of scrutiny, across the two acute angles, in directions 

 comprising respectively inclinations of 90' and 45° to the axis. 

 The directions of the cut faces were referred by reflection lo the 

 cleavage planes, a'ld thereby to the axis. The light observed 

 was the bright D of a soda-llame. 



The result obtained was that Huyghens's construction gives the 

 true law of double refraction within the limits of errors of obser- 

 vation. The error, if any, could hardly exceed a unit in the 

 fourlh place of decimals of the index, or reciprocal of the \\ave- 

 velocity, the velocity in air being taken as unity. This result is 

 sufficient absoluli-ly to disprove the law resultmg from the theory 

 which makes double refraction depend on a difference of inertia 

 in different directions. 



I intend to present to the Royal Society a detailed account of 

 the observations ; but, in the meantime, the publication of this 

 preliminary notice of the result obtained may possibly be useful 

 to those engaged in the theory of double refraction. 



Paris 

 Academy of Sciences, July S. — M. Becquercl presented a 

 memoir on the influence of pressure upon the phenomena of 

 endosmose and exosmose. — M. E. Becquerel jn'escnted a report 

 upon the recent memoir by MM. F. Lucas ami A. Cazin on the 

 duration of the electric spark. — M. Wurtz communicated a note 

 by M. (;. Salet on the primary spectrum of iodine. — M. II. 

 Sainte-Claire Deville presented a note by M. L. Cailletet on the 

 compres^ibility of liquids under high pressures, giving the co- 

 efficients of compressibility of various fluids at certain tempera- 

 tures and pressures, and describing the apparatus by means of 

 which these results were obtained. — M. plammarion prcented 

 some remarks on a part of a recent note by M. de Fonvieile on 

 some observations made during the ascents of the balloon Lea, 

 relating especially to the halo observed round the shadow of the 

 balloon, and accepting the explanation of M. Tissandier. — M. 

 Becquerel presented a memoir on some effects of slow actions 

 produced during a certain number of years. In this paj^cr the 

 author described certain products, having their analogues in 

 nature, formed by slow action in a vessel hermetically closed for 

 twenty years. They include crystals of arragonite and of 

 rhombohedric carlionate of lime, crystals of arseniate of lime, 

 glauberite — with potash instead of soda, crystals of carbonate 

 of lead, and malachite. — >t. T. Schlresing presented a second 

 note on the solution of carbonate of lime by carbonic acid, and 

 M. Wurtz a note by M. C. Lauth in reply to a recent note by 

 MM. Girard and De Laireon the manufacture of anihne colours. 

 — M. Bardy also forwarded a note on the last-mentioned subject. 

 — Analyses of a new variety of amljlygonite from Montebras, of 

 amblygonite from Hebron in Maine, and of wavellite from 

 Montebras, by M. F. Pisani, were communicated by M. If. 

 Sainte-Claire Deville. — M. Wurtz communicated a note by MM. 

 C. Friedel and R. D. Silvaon a third bichlonnated propylene. — 

 M. li. J. Maumenii presented a memoir on two new acids pro- 

 duced by the oxidation of sugar, in illustration and support oi his 

 general theory of chemical action. — M. Balard communicated 

 a note by M. J. Riban on the aldanes, or aldehydes con- 

 densed with ehmination of water, the agents employed by 

 him for the removal of the water being sodium or 

 zinc. For these bodies he projioses the name of aldanes. 

 ■ — A third part of MM. Beithelot and Longuemine's ther- 

 mochemical researches upon bodies formed by double de- 

 composition was read. The substances experimented on were 

 protochloride, perchloride, oxychloride, and protobroniide of 

 phosphorus; and the results obtained by treating these bodies 

 with water and with potash are here stated. — M. C. Bernard 

 described the evolution of glycogene in the eggs of birds, in con- 

 tinuation of his previous communications on glycogenesis in ani- 

 mals. — An extract from a letter of the Abbe David to M. 

 Milne-Edwards containing some zoological observations made in 

 the province of Tche-Kiang, was read. The author notices a 

 new species of Ibis (/. sinensis), a new h'alcon (F. saciviilis) a 

 new I'Janns (E. siiii'iisis), and a new Salamander of the genus 

 Cyiiohs ( C. oricntalis). lie aLo mentions the occurrence of some 

 other birds, and of a great freshwater tortoise attaining a weight 

 of 200 to 300 pounds, supposed to be Chiria indtca, — MM. 

 Jamin and De Laures presented a note on the alterations of 

 weight undergone by the human body in baths, in which they 



confirm the results of M. Durrien, according to which the 

 weight of the body is maintained or increased by absorption so 

 long as the temperature is low or moderate, but diminished by 

 immersion in warm water. — M. Bernard presented a filth note 

 by M. Paul Bert on the influence exerted by changes •" 

 barometric pressure upon the phenomena of life. — MM. P. van 

 Tieghem and G. Le Monnier presented a ;oint note describing 

 the zygospores of yl/«(W //y'lvwjrcj- ,• and M. Duc'iartre a paper 

 by M. Duval-Jouve on a new species of the genus Athcnia {. /. 

 Baminditnii) from the south of France. — M. .Milne-Edwards 

 communicated a note by M. H. Filhol on the carnivora and 

 chiroptera, of which the fossil remains are found in the deposits 

 of phosphate of lime at Caylux, Fregols, and Concots. The 

 autiior describes the jaw of a cat, which he name-; Psetcdelurus 

 Edwardsii ; a jaw serving as a link between the cats and mus- 

 telida:, upon which he founds a new genus, and which he names 

 ylLluyogalc inleruudia ; and two jaws of dogs, described as 

 Canis caylitccnsis and C. Gaiidiyi. At Fregols there is a breccia 

 composed entirely of the bones of bats, which the author refers 

 to A'/iinolop/tiis, under the name of A', aniiipius. 



PAMPHLETS RECEIVED 



ENGLrsH.— Proceedings of a Joint Meeting of the Malvern, Bath, and 

 Woolliope Field Clubs. —Discussion of the Anemometrical Results furnished 

 by the Anemometer at Sandwick Manse, Orkney, 1863-68.— On the Law 

 which regulates the frequency of the pulse : A. H. Garrod — Report of the 

 Winchester and Hampshire Scientific and Literary Society, iS/o-yt. — Journal 

 of Mciual Science, July. — Memoirs of the Geological Survey of England ami 

 Wales,— Man in the Crag. — Scottish Naturalist, July.— Quarterly Journal 

 of Microscopical Science. July.— Naval Science, No. 2 — Quarterly Journal 

 of Science, )uly. — The Glacial Geology of Lancashire and Cheshire : T M. 

 Keade. — Vaccination and the Vaccination Laws: Rev. W. H. Rothery. — 

 Journal of the Society of Telegraph Engineers, No. i.— On the Change of 

 Climate during the Glacial Epoch : Jas. Geikie. — Introductory Lecture de- 

 livered at the Jniversity of Glasgow : A. Dickson. — Route for Steamers from 

 Aden to the Straits of Siinda.-On the Winds of the North Atlantic— Stric- 

 tures on Darwinism : H, H. Howorth. Part I — E.vtracts from the Opening 

 Address of the President of the Botanical Society of Edinburgh : Sir W. 

 Elliot.— Annual Address to the Victoria bistitute : Rev. J. Kirk.— Explosive 

 Agents applied to Industrial Purposes : F. A. Abel. — Remarks to accompany 

 the Monthly Charts of Meteorological Observations. — Grevillea, No. i : M. 

 C. Cooke. 



American and Colonial. — Die neue entdeckte Geyser gebiete am 

 Obcren Yellowstone u. Madison Rivers ; F. V. Hayden. — Illustrated Cata- 

 logue of the Museum of Comparative Zoology at Harvard College. No. 6 : 

 T. Lyman— Animal Report of the Trustees of the Museum of Comparative 

 Zoology at Harvard, — The Eozoon Limestone of Easteren Massachusetts: J. 

 1!, Perry.— Fiftli Annual Report to the Trustees of the Peabody Institute, 

 Baltimore.— t)n the Structure of the Skull of Mosasauroid Reptiles : Prof. O. 

 C. Marsh.— Preliminary description of Hesperoriiis regalis : Prof. O. C. 

 Marsh.— Statement relating to the Home and Foreign Trade of Canada : W. 

 J. Patterson. — Monthly Record of Results of Observation in Meteorology 

 and Terrestrial Magnetism at Melbourne, March 1872. — Supplement to Fifth 

 Annual Report of the U.S. Geological Survey of the Territories : F. V. Hay- 

 den. — Popular Science Monthly, No.s. 1-3. — Mineral Statistics of Victoria, 

 i87r. 



Foreign. — Sulla determinazione dei pesi molecolari delle sostanze saline : 

 Dr E. Paterno.— Osservazione dell'cclisse totaledel 12 Dec, t87i,a Pooda- 

 cottah neir Indostan : Prof. L. Respighi.— Zeitschrift fiir Ethnolojie, 1872. 

 No. 3. — Journal d'Anthropologie, 1872. No. 3. — Cronica Scientifica : P. 

 Tacciiini. 



CONTENTS Page 



The Last Attack ON Darwinism. By Alfred R.Wallack, F.Z.S. 237 



Our Book Shelf 240 



Letters to the Editor: — 



Ocean Currents— James Croll, F.G.S 240 



The Melbourne Telescope— Wakren De La RlE, F.R.S. ... 241 

 On the Rigidity of the Earth, and the Liquidity of Lav.as- Rev. 



O. Fisher, F.G.S 241 



The Method of Least Squares— Prof. AsaI'H Hall 241 



S.Oar R.iiiili^a-GEORGE DiNNOW 242 



IIu. V:.: Mt, hanism-WiLLiAM Earlev 242 



In; 11 s of' Lightnii\g-^B'. W. Smith, F.R.V.S.' '. .' '. 242 



.^■,•1' I ill ik;< I t.Tirn — Alex. Beazelev, C.E 242 



TeCHNR.M- KliKAtlON =43 



Volcanoes of Central France. By Henry Norton .... 243 



Water Analvsis. II 244 



The Blind Fishes of the Mammoth Cave and their Allies. 



By F. W. PUTMAN. (IVith Illustration.-) 246 



Notes 249 



Historical Eclipses. By J. R. Hind, F.R.S 251 



On Photograi-hic Irradiation in Over-Exi-osrd Plates. By 

 Lord Lindsav, F.R.A.S., and A. C. Ravnard, F.R.A.S. (fC/V/r 



Illustrations.) 253 



Scientific Serials 254 



Societies and Academies 2.S7 



Pa»iphlets Received 258 



Errata. — Vol. vi , p. 221, col. 2, line 34 from bottom, for ** Chladin," read 

 ■'Chladni ;" and p. 222, line 22 from to{>, and also in Contents, for "Allen," 



