284 



NATURE] 



\_7an. 23, 1879 



he was making for ibe purpose of measuring what is known as 

 the "Thomson Effect," viz., the convection of heat by electric 

 cvirrents from a cold to a hot part of a bar, or vice versd. The 

 method had occurred to him while testing the electric conduc- 

 tivity of bars heated for Forbes' conduction experiment. — A 

 paper was read by Dr. Macfarlane and Mr. P. M. Playfair, on 

 the disruptive discharge of electricity, in confirmation of former 

 experiments of a similar nature. They found former anomalies 

 with sparks of more than a certain length between two spheres, 

 to be due to discharge by small sparks, and beyond that to 

 escape into the air from the insulated wire. In the case of 

 discharge between a plate and a point, there was a gradual 

 increase in the difference of potential. Up to a certain 

 limit the sparks were white ; beyond that the sparks were 

 violet, and there was very slight increase in the difference 

 of potential required. On discharging thrc^ugh solid paraffin it 

 was found that the first spark was by far the largest, and on 

 examination the paraffin was found perforated in a zigzag man- 

 ner, and the sides of the perforation were charred. The solid 

 paraffin had twice as great electric strength as the same paraffin 

 in the liquid state, and five times the electric strength of air. 

 They found that the electric strength was a very definite method 

 of distinguishing between different paraffins, but somewhat dif- 

 ficult of application. — Prof. Tait showed some pieces of sheet 

 or tape india-rubber which Mr. Maclachlan of Mitcham had 

 used to insulate wires, and which, after being stretched for some 

 years, were found to be permanently strained ; but they imme- 

 diately regained their former dimensions on being dipped into 

 hot water. The same phenomenon was true, he found, of 

 india-rubber which, while warm, was stretched out nearly to 

 rupture, and then kept stretched till cold. Prof. Clerk Maxwell 

 had found a similar property true of gutta-percha pulled out 

 when cold after being boiled. On heating it before a fire it 

 took a peculiar form. 



Vienna 



Imperial Academy of Sciences, December 5, 1878. — On 

 twins ; a contribution to human physiology, by Dr. Gohlert. — 

 On the diffusion of liquids, by Prof. Stefan. — Determination of 

 the path of the third comet of 1877, by Herr Zellr, 



December 12, 1878. — On the fish species in the two lakes of 

 Lower Austria, the Erlaph and Lunzer Lakes, by Dr. Fitzinger. — 

 New observations on sounding air columns, by Prof. v. Lang. 



Paris 



Academy of Sciences, January 13. — M. Daubree in the 

 chair. — The following papers were read : — On the construction 

 of bridge-arches realising the maximum of stability, by M. 

 Villarceau. — Researches on ozone and on the electric effluve, by 

 M. Berthelot. Oxygen (i vol.) and hydrogen (2 vols.) do not 

 combine under action of the effluve, though the tension be nearly 

 that which gives, through air, sparks 7 to 8 ctm. long. O will 

 combine with the metals, sulphurous acid, nitrogen, &c., under 

 such conditions. CO {2 vols.) and O (l vol.) combine under 

 like tensions ; but the reaction is incomplete ; and even with 

 excess of O it is so. The effluve, acting on a mixture of CO2 

 and O partly decomposes the former, and the O contains ozone ; 

 acting on pure COj in a space without mercury or oxidable 

 bodies, the effects point apparently to the existence of percarbonic 

 acid. — On the formation of ethers of hydracids in the gaseous 

 state, by M. Berthelot. — Are there, among low organisms, 

 species exclusively a'erobies.zxsA oxhsxi exclusively anaerobies ? 

 Should all these beings be ranged in two or three classes (Pasteur) 

 or in one only ? by M. Trecul. He argues for one class only, 

 each species being capable of presenting at once one or several 

 aerobian states, and one or several anaerobian. — Reply to M. 

 Berthelot, by M. Pasteur. — Researches on the compressibility of 

 gases, by M. Cailletet. He describes the manometer he uses ; a 

 tube of soft steel wound helically round a vertical cylinder, by 

 turning which the tube is sent down a deep pit or wound up again. 

 The lower end of this tube is connected with a laboratory-tube, 

 in which is inclosed the piezometer containing the gas, and 

 mercury is introduced into the apparatus. This tube is suspended 

 by a fine graduated steel wire, the length of which unrolled 

 iiieasures the pressure. M. Cailletet tabulates his numerical 

 results with nitrogen, which, it appears, contracts at first more 

 than according to Mariotte's law ; its compi-essibility then 

 decreases (as in the case of air). It is about a pressure of 70 

 metres of mercury, that the gas presents this curious maximum. 

 — The pol}'morphism of Agariciis mclleus, Vahl., by M. I'lanchon. 



— Experiments relating to the action of waves on beaches and on 

 artificial rock-work, by M. De Caligny. He reproduces in an 

 artificial canal effects noticed at the rock-work of Cherburg, where 

 large waves which, at low water, rolled the blocks toward s the sum- 

 mit of the talus,had an underminingeffectathigh water. — M.Monot 

 presented some specimens of results he has obtained in manu- 

 facture of various kinds of crystal. — The phylloxera in Panama, 

 on the Vitis caribaa, D.C., by M. Collot. — On the employment 

 of oil of asphalte against phylloxera, by M. Berton. Some one 

 told him, when exploring the Dead Sea, that this oil had saved 

 the vineyards of Judea from a worm (phylloxera?). — Letter to 

 the President of the Commission on phylloxera, by M. Truchot. 

 — MM. Felson and Chartre communicated a detailed catalogue 

 of those erratic blocks most remarkable as regards the history 

 of glacial phenomena. — The General- Inspector of Navigation 

 presented data concerning flood and low-water of the Seine in 

 1878. — Observations of Saturn's satellites, at the Observatory 

 of Toulouse, in 1877 and 1878, with the large Foucault tele- 

 scope, by M. Baillaud. — New compound prism for direct-vision 

 spectroscope of very great dispersive power, by M. Thollon. 

 This sulphide of carbon prism is closed laterally by crown glass 

 prisms, whose refringent angles are in opposite direction to that 

 of the sulphide. The compound prism gives the enormous dis- 

 persion of 2''0 angular distance of the D-lines, as compared 

 with 45" for sulphide of carbon. Substituting the new prisms 

 in his former spectroscope, he got a dispersion equivalent to that 

 of 16 sulphide of carbon prisms of 60°, or 31 prisms of index 

 I "63. It gave 12' angular distance in the D-lines, and it pre- 

 sents quite new aspects of the spectrum. All the lines (newly) 

 resolved were found to belong to different substances. — On M. 

 Thollon's spectroscope, by Si. Laurent. — On determination of 

 the variations of level of a liquid surface, by M. Renou. A 

 claim of priority. — Synthesis of uric derivatives of the series of 

 allophane, by M. Grimaux. — Action of diastase, saliva, and pan 

 creatic juice on starch and glycogen, by MM. Musculus and 

 De Mering. — New observations on the development and meta- 

 morphoses of Taenias, by M. IMegnin. Certain unarmed and 

 armed Taenias are two adult forms of the same worm, their dif- 

 ferences due exclusively to the conditions of their development. 

 — Observations on Majorca and Minorca (continued), by M. 

 Hermite. — New observations on the danger of use of powdered 

 borax in meat-preserving, by M. Le Bon. 



CONTENTS Page 



Gas versus Electkicity. By W. H. Preece 261 



The "Novum Okganum." By G. F. Rodwell 262 



The American Cyclopedia 264 



Our Book Shelk :— 



Buckley's " Fairy-Land of Science " 265 



Christy's " New Commercial Plants, with Directions for th?.ir 



Growth and Utilisation " 265 



Letters to the Editor :— „ 



American Weather. — E. D. Archibald 266 



The Microphone. — Dr. V. A. Julius 266 



The Formation of Mountains.— Rev. O. Fisher 266 



Leibnitz's Mathematics. — James Bottomlev; Dr. C. M. Ingleby 267 



German Degrees. — Prof. Dr. E. Lommel 267 



Feeding a Python. — N. B. D 267 



Shakespeare's Colour-Names. — Edward T. Hard.man .... 267 



Intellect in Brutes.— Rev. Edward Geoghecan 268 



Our Astronomical Column :— 



Olbers' Comet of 1815 268 



Meteorological NotesJ . . ' 269 



Geographical Notes, 270 



The Geological History of the Colorado. River and Plateaus, 



II. By Capt. C. E. Dutton {With Illustrations') 272 



Inclination of the Axis of Cyclones and Anticyclones. By 



Rev. W. Clement Ley 275 



Bartolomeo Gastaldi 275 



On the Determination of Absolute Pitch by the Comaton 



Harmonium. By Lord Rayleigh, F.R.S .275 



The Fissures of the Cerebral Hemispheres in Ungulata. By 



V. Horslev (IVith Illustrations') 27 



Notes ^78 



On the Lavas of Hekla, and on the Sublimations produced 

 during the Eruption of February 27, 1878. By G. F. Rodwell 280 



University and Educational Intelligence 281 



Scientific Serials 281 



Societies and Academies • • • 2S2 



