20 



NA TURE 



{Nov. 2, 1 8; I 



mathematical theory of dynamical electricity, and a memoir 

 by M. E. Mathieu on the intearation of equitions to the partial 

 differences of mathem'atical physics. — M. ilu Moncel presented 

 some observations relating to a recent C'immnnication liy M. 

 Ruhmkorff upon some exi>eriments \a magneto-electric ii\Juc- 

 tion, In which he claimed to have already ascertained and pub- 

 lished facts analogous to those of the German author — M. P. 

 A. Favre read a continuation of hi; tliermic researches upon the 

 electrolysis of the hydracids. — A fifth letter from Father Secchi 

 on the variou; aspects of the protuberances and other remarkable 

 parts of the surface of the sun was read, in which he describes 

 the results of simultaneous observations m.ide by himself at Rome, 

 and by M. Tacchini at Palermo. — M. Seccbi aho presented a 

 note on a new method of observing the eclipses and passages of 

 Venus, by means of a spectroscopic apparatus modified by having 

 at a distance of about 20 centimetres in hunt of the spectroscope, 

 an additional prism having its refring :;nt angle parallel to the 

 fissure. — The chemical papers were as follows : — a theory of 

 simple reactions limited by inverse action, and an application of 

 the same to the transformations of phosphorus, by M. J. Lemoine. 

 ■ — Researches in chemical statics, by M. Stas, containing a discus- 

 sion of the phenomena which occur in the precipitation of di- 

 lute solutions of salts of sdver by hydrochloric, hydrobromic, 

 and hydriodic acids, and by chlorides, bromides, and iodides. 

 This paper contains some results of great importance in 

 the analysis of bodies containing silver. — The conclusion of the 

 second part of M. Berthelot's investigation of the ammoniical 

 salts. — A note on the transformation of glucoses into monatomic 

 and hexatomic alcohols, by M. G. Bouchardat, communicated 

 by M. A. Wurtz. The author acts upon the glucoses by means 

 of an amalgam of sodium. He describes its action upon glucose 

 and sugar of milk, — A note on the hexabroniide and hexachloride 

 of silicium, by M. C. Friedel, aUo presen'ed by M. A. Wurlz ; 

 and a note on the method of determining the gases evolved by an 

 explosion of nitroglycerine, by M L. L'Hote, presented by 

 General Morin. From the researches of the last-mcnlioned 

 author it appears that I gramxe of nitroglycerine produces 2S4 

 cub. centim. of gas, containing by volume 45 72 of cubonicacid, 

 20 '36 of binoxide of nitrogen, and 33 92 of nitrogen. — M. Elie 

 de Beaumont called attention to sjme specimens o( native phos- 

 phate of hme from Caylux and Cajare, and noticed the import- 

 ance of these deposits for agricultural purposes. M. Combes also 

 remarked upon this subject. — M. Chaiielas presented a note on 

 a remarkable meleor ol;served during the night of the 19th 

 October. 



Phil.idei.I'HTA 



Acadeiny of Natural Sciences, May 9. — The President, 

 Dr. Ruschenberger, in the chair. — Prof. Cope demonstrated 

 some anatomical points of importance in the classification 

 of some of the Siluroids of the Amazon, noticing first 

 those which have no swimming b'adder, but having the 

 post-temporal bone pierced in a sieve-like manner, forming 

 minute tympana ; these he characterised as Olocinclus. Others 

 having huge swim-bladders, gun-boat style of shape. No adi- 

 pose fin ; the back naked. No lyre plate, indicated as Zathorax. 

 A third, body protected by bony shields above. No adipose fin ; 

 the scapular arch dermobssified and lyre-shaped below ; vcv^\~ 

 csXi&zs, Physopy.\is lyra A fourth, shielded all over its sides, 

 with the under lip turned back, genus CoryJoras. A fifth, where 

 the under lip is separated, except at the ends, forming loops, 

 named Biochis. In the sixth, where the lips are separated from 

 the beard distally forming chin beards, indicated as Diancina. 



May 16 — Dr. Carson, Vice- Presidenr, in the chair. — "Re- 

 mains of Mastodon and Horse in Norili Carolina." — Prof. Leidy 

 exhibited two photographs, received from Prof. W. C. Ktrr, 

 State Geologist of North Carolina, representing some remains of 

 Mastodon ainon'iiDijis found in that State. One of the specimens 

 represented is that of the greater part of the lower jaw of a 

 mature male, retaining both incisor tusks and the last two molar 

 teeth. The latter, with their angular lobes separated by deep 

 angular and nearly unobstructed valleys, are quite characteristic 

 of the species. The incisors are an inch and three-fourths in 

 diameter. The last molar has four transverse pairs of lobes and 

 a well-developed heel. The penultimate molar has three trans- 

 verse pairs of lobes. The specimen was obtained from gravel 

 overlying the mioccne marl near Goldsboro', Lenoir Co., N.C, 

 An isolated last lower molar of the same species, represented in 

 company with the jaw, was obtained in Pitt Co. — Prof. Leidy 

 also exhibited a specimen of an upper molar teeth, which Mr. 

 Timothy Conrad had picked up from a pile of miocene marl at 



Greenville, Pitt Co., N.C. He suspected, from its size and 

 intricicy in the folding of the enamel of the i-Ie's at the mi Idle 

 01 the triturating surface, that the tooth belmige 1 to the )>ost- 

 pliocene Eijuus coniplicalus, and was an acc'dentxl occupant of 

 the miocene marl. It may, however, belong to a llipparion of 

 the mioccne period, but the imperfection of tlie sjiecimen at i's 

 inner part prevented its positive generic determination. 



BOOKS RECEIVED 



ENGLfSH— ,\ Muiml of th; Anuomy of Verte'jnteJ AninijU : Vt<^'. 

 Huxley (Caircli lit -\ -T'yninym'c Catalog le of Diinul Lepiilo jttr.i : 

 W F. Kirbv C-'ui \ . .1-11— liescriptioa of an Electri; Telegraph: bir 

 Francis Ronal.l (iVil i ru ui 1 Norgate) —Spiritual and Animal Magnetistn : 

 Prof. J. G. Zerll. I l.r.l .MLkt) — An Eletnentary Treitise on Statics: J. W. 

 Mulcaster (I'aylor and Krancis). 



FoiSEiGN.— (Through Williams ant Norjatc.j-Verhandlungcn des inter- 

 nationalen Congress fiir .^Iterthumskunde u. Geschichte zu Bonn. 



DIARY 



THURSDAY, Novembers. 

 LiNNEAN SociETV, at 8.— On the Origin of Insects : Sir John Lubbock, 



Bart., F.R.S.— Notes on the Natural History of the Flying Fish : Capt. 



Chimmo —On a Chuiese Gall, allied to the European Artichoke G.1II : 



A. Muller, F.L.S. 

 Chemical Societv, at 8.-0n Anthraflavic Acid : W. H. Perkin. 

 London Institutio.v, at 7.30. — On Michael Faraday ; the Story of his Life : 



Dr. J. H. Gladstone, F.R.S. 



FRIDAY, November 3. 

 Geologists* Associatio.m, at 8. — On the Old Land Surface; of the Globe 

 Prof. Morris. 



MOKDAY, November 6. 



-On Elementary Ph; siology (IL): Pr.f. 



Huxley, LL.D., F.R S. 

 Anthropological lNSTiTt;TE, at 8. — On the Order of Succession of the 

 several Stone Implement Periods in England: J. W. Flower, F.G.S.— 

 Notes on some Archaic Structures in the Isle of Man : A. L. Lewii. 



■ofBh 



TUESDAY, November 7. 



it S.so.-OntheRelgk 



er, F.R..S'"— 

 i): Herbert 



Assyriarzs; H. Fox Talbot. 

 H^CKNEV Scientific Association, at 7.30.— Co 

 Zoological Societv, at 9.— Report on Recent Add.tions to 

 Menagerie : The .Secretary —On the Recent Ziphod \Vh.ile 

 scription of the Skeleton of Beraniius nntouxii ; W. H. Floi 

 On the Habits of the Nose-horned Viper (yi/>i!ra iwsicori 

 Taj lor Ussher, C.M.Z S. 



WEDNESDAY, November 8. 

 Geological Societv, at 8 —Notes on the Diamond Gravels of the Vaal in 

 South Africa : G. W. Stow.— On the Geology of the Diamond Fields of 

 South Africa: Dr. John Shaw.— Notes on .some Fossils from the Devonian 

 Rocks of the Witzenberg Flats, Cape Colony : Prof. T. Rupert Jones. 



THURSDAY, November 9. 

 London Mathematical Society, at 8.— On the Partition of an Even 

 Nu'nberinto two Primes; J. J.Sylvester, F.R.S. 



CONTENTS Page 



Rii-PLES AND Waves By Prof. Sir William Thomson, F.R S. . . i 



ALLBtJTT ON THE OPHTHALMOSCOPE. By Dr. H. PoWER .... 3 



Our Book Shelf 4 



Letters to the Editor : — 



An Universal Atmosphere— W. Mattieu William,, F.C S. . . s 



Pendulum Autographs —Geo. S. Cark 6 



Jh;.\ogenous Structures in Coal-Plants.— Prof. W. C. Williamson, 



F.R.S 6 



Classificationof Fruits.— Dr. Maxwell T. Masters, F.R.S. . . 6 



The Berthon Dvnaraometer.—Rev. T. W. Webb, F.R.A.S. ... 6 



New Form of Cloud 7 



Spectrumof Blood— H. C. Sorby, F.R.S 7 



Earthquake in Burmah. — Major Charles Halsted 7 



A Plane's Aspect.— Dr. T. A. Hirst, F.R.S. ; Dr. C. M. In- 



GLEBY ; J. K. Laughton 7 



Geometry at the Universities — RiCHD. A. Pkoctoe, F R. A.S. . . 7 

 Deep-Sea Dredging in the Gulf of St. Lawrence. IJy J. F. 



Whiteaves 8 



The Rede Lecture at Cambridge 9 



The Conjoint Examination Scheme 9 



Sir Roderick Murchison. By Prof. Arch. Geikie, F.R.S. (li'st/i 



Portrait.) 10 



HoMOPLAsv and Mimicry. By Alfred W. Bennett, F.L S. . . . 12 



Notes 12 



The Geognosy of the Appalachian and the Origin of Crys- 

 talline Rocks. By Prof T. Sterry Hunt 15 



Instructions for Observers at the English Government 

 Eclipse Expedition, 1871. II —Polariscopic Observations. (IVith 



Diagrams.) 18 



Scientific Serials iq 



Societies and Academies j^ 



Books Received 20 



