j8o 



NATURE 



\yuly2\, 1881 



lion of the so-called classificatory methods. The classification 

 proceeds according to difference of ijenr. ration, and is merely one 

 mode in which the relationship ideas may be expressed in Mords. 

 Mr. Mor"aii's hypothesis of a consanijnine and of a Panaluin 

 family are contradicted by the data which they are introduced to 

 explain. — Prof. Tait communicated a note on a proposition in 

 the theory of numbers. 



Paris 



Academy of Sciences, July 11. — M. Wurtz in the chair.— 

 The following papers were read : — On the formation of the tails 

 of comets, by M. Faye. A reply to .M. Flammarion. The tail is 

 not rigidly connected with the nucleus. The repellent force is 

 proportional to the surfaces, is weakened by interposition of a 

 screen, is not propagated instantaneously, and varies in inverse 

 ratio of the square of the distance. — Theory of plane flexion of 

 solids and consequences relating to c rt^truLtion of astronomicl 

 telescope-, and to their regulation, getting rid of deviations of 

 the optic axis due to flexion, by M. Villarceau. — On the velocity 

 of propagation of explosive phenomena in gases, by M. Beitlie- 

 lot. The experiments were with mixtures of hydrogen and 

 oxygen and of carbonic oxide and oxygen (2 vols, to I). These 

 were placed in a long iron tube (open or close, fixed in various 

 positions, &c ), and were inflamed with an electric spark ; the 

 passage of the wave was measured by an electric method. The 

 velocity w as in general about 2500 m. pei- second. Exploive 

 phenomena are more conjplex than a simple motion of translation 

 or even than the propagation of a sound wave, — Reply to iM. de 

 Lesseps on M. Roudaire's project, liy M. Losson. — On the bor- 

 ings made in strata to be travered by the Panama Canal, by M. 

 de Lesseps. The strata of large section will offer sufficient con- 

 sistency for formation of talus, while not i>re enting there-i-tance 

 of hard rock. — Study in experimental thermodynamics on steam- 

 engine-', by M Ledieu. — Photography of the s;iectrum of come! 

 b 1881, by Dr. Hugi;ins. M. Herthclot thought the spec'ra ren- 

 dered probable the electric origin of the proper light of comets. 

 — Influenee of jihosphoric acid on phenomena of vegetation, by 

 M. de Gasparin. — Remarks on the accidents c:ustd by u e of 

 sulphide of caibon in treatment of vines in th? South of France, 

 by M. Cornu. — Shocks of an earthquake at Gabes on June 13 

 were reported. — On the comet of itJSi observed at the Imperial 

 Observatory of Rio de Janeiro, by M. C'ruls. — Observations 

 on the same comet at Algieis Observatory, by M. Trc'pied. 

 — Further observations by M. W. If and by M. Thollon 

 (See page 261). — Attempt at explanation of the tails of 

 comets, by M. Picart. A comet, consisting of gaseous matter 

 and luminous ether, appears, at a distance from the sun, in 

 spheroidal form (the luminous ether being then invisible). Put 

 on Hearing the -un the luminous ether of that star repels the 

 luminous ether of the comet ; hence the tail. — On the polarisa- 

 tion of the li^ht of c imets, by M. Prazinowski. The comet is 

 shown to rcfl.-ct solar light abundantly — New method of deter- 

 mining certain con-tants of the .sextant, by M. Gruey. — On 

 Kleinian groups, by M. Poincare. — On a general means of deter- 

 mining the relations between constants contained in a particular 

 solution, &c. (continued), by M. DiUner. — On the three centrifugal 

 axes, by M. Bras-inne. — On the absolute measurement of currents 

 by electrolysis, by M. Mascart. By careful experiment he finds tlie 

 intensity of the current capable of producing in one second the 

 electrolysis of i equiv. of a substance expressed in milligrammes is 

 equil to 9601 w., or say 96 webers. — On the reality of kine- 

 matic equivalence in undulatory optics, by M. Crouillebois. M. 

 Cornu made some remark-;. — On the chlorides of iron, by M. 

 Sabatier. — On the oxychloridesof strontiumandof barium, by M. 

 Andre. — Experimental researches on decomposition of picrate of 

 potash ; analysis of pr.iducts, by MM. Sarrau and Vieille.— On 

 decipium and samarium, by M. Delafontaine. He reserves the 

 name deripiiim for the radical of the earth having an equivalent of 

 about 130 ; samarium for the other metal (in samarskite) who've 

 absorption spectrum was described by M. Lecoq. (The 

 equivalent of samarine is probably under 117.) — Action of 

 peroxide of lead on alkaline iodides, by M. Ditte. — On ethers 

 of morphine con-idered as phenol, by M. Grimaux. — Re- 

 searches on t.-rtiary raonamines ; III. Action of triethyl- 

 amine on ethers with hydracids of secondai-y and tertiary 

 alcohols, by .M. Reboul. — On cyani-ed camphor, by M. Haller. 

 — On the composition of hydrosulphite of soda and of hydro- 

 sulphurous acid, by M. Bernthsen. — Two facts relating to deci- 

 lene (oil of turpentine), by M. Maumene. — On viscose, or the 

 gummy substance of viscous fermentation, by M. Bechamp. — 



Determination of urea with the aid of titrated hypobromite ot 

 soda, by M. Quinquaud. — Researches on animal heat, by M. 

 d'Arsonval. By direct calorimetry he proves the great absorp- 

 tion of heat by the egg in ineubation during the first day (a fact 

 otherwise proved by M. Moitessier). Oxygen is abundantly 

 abs rbed and carbonic acid emitied. During sleep or complete 

 rest, animals absorb much oxygen and make little heat, the emis- 

 sion of carbonic acid varying slightly. The author hardly ever 

 found agreement between the heat mea ured directly and the 

 heat calculated from respiratory combustions; this is becau; e 

 organic combustion is of the order '\ fermentation. The chemi- 

 cal methed gives the sum ; direct calorimetry the difference. 

 The two methods should be combined. — Action of mate on gases 

 of the blood, by MM. d'Ar.sonval and Couty. — Absorbed by the 

 stomach or the veins, mate rlimini hcs the carbonic acid and the 

 oxygen of arterial and venous blood enormously (sometimes a 

 third or a half of the normal- quamity) — On the seat of cortical 

 epilepsy and of hallucinations, by M. Pasternatzky. Cortical 

 epilepsy is really what the na ne implies. The hallucinations he 

 produced in a dog with absinthe he attributes to excitation of the 

 sensitive sub-cortical centres by that sub tance. — On the altera- 

 tions of the cutaneous nerves in pellagra, by M. Dejerine. — On 

 venous cireulaii u by influence, by M. Ozanam. Among the 

 various causes of progre-sion of blood in the veins is an impor- 

 tant influence exercised on each vein by the artery associated 

 with it. The vein walls experience a rebound from the arterial 

 movements. — On the structure 1 f the oothecEe of Mantes, and 

 on the hatching and first moulting of the larvte, by M. Bron- 

 gniart. — Chemical researches on the product of secretion of the 

 ink-bag of Cephalopoda, by M. Girod. — On the synchronism of 

 the marine carboniferous fauna of Ardoisi^re (Allier), and the 

 anthraciferous fauna of Roannaisand Beaujolais, by M. Julien. — 

 M. Laurey noted, about the cimet, that the sunlight illuminated 

 only the left parr, leaving the right dark — a true cometary phase. 

 ViENN.A 

 Imperial Academy of Sciences, June 23. — L. T. Fitzinger 

 in the chair. — L. T. Fitzinger, examination of some species which 

 were till now inc irporated with the species Vrsus arctos. — F. 

 Steindachner, conlriliutions to the knowledge of African fishes 

 (contains a descript on of a new species of Sargiis from the Gala- 

 pagos Islands), — Joh. Mayer, on the trajectory of the 18S0 ^cornet. 

 — Max. Margules, on the moiions of viscous liquids and on the 

 figures of motion. — F. Strdhmer, on the occurrence of ellagi: 

 acid in pine-bark. — Ernst Schneider, a sealed packet (ex- 

 periment on the construction of high- power telescopes).— MM. 

 Neumayr and Eniil Holub, on the fossils at the Uitenhage 

 formation in South Africa. --M. Neumayr, studies on fossil 

 Echinodermata. — V. v. Lang, on the coefficient of refraction of 

 concentrated solutions of cyaniiie. — L. Haitinger, on the occur- 

 rence of malic and citric acid in Chelidonium mai'its. — Dr. T. 

 Puluj, a realed packet (without inscription). 



CONTENTS P.OB 



Inheritance. By Charles Dakwin, F.R.S 257 



Volcanoes. By G. F. Rodwell =57 



The Figure op the Earth =59 



Letteks to the Kditok : — 



Special Sohr Heat-Radiations and their Earth.i=elt Effects.— Prof. 



Balfour Stewart, F.R.S 260 



How to Prevent Drowning.— Prof. Joseph Le Conte 260 



Optical Phenomenon.— W, J. Still.vian 2«o 



Implements at Acton.— Spencer Geo. Perceval 260 



Lightning.— A. Hall, Jun 261 



The Comet 261 



Width of Mr. Ruthesfurd's Eulings. By Prof. C. S. Peirce . 262 



City and Guilds op London Institute 262 



Notes 264 



mateorological notes 266 



Solar Phvsics— The Chemistry of the Sun, I. By J. Norman 



LOCKVER, F.R.S. (With IllHstratious) 267 



Some Observations on the Migration of Birds. By W. E D. 



^zo-vr (With Diagraiii) , 274 



(Tn thb Equivalents of the Elemrntarv Bodies Cossidered as 

 Representing an Akith.metical Progression Deducible from 



Mendeleeff's Tables. By Prof. J. P. O'Reilly 274 



Our Astronomical Column ; — 



The Variable Star x Cygni 277 



Comet 1881 b 277 



Comet 1881 I- 278 



Near Approach of Veniis to 107 Tauri 278 



Scientific Serials 28 



Societies AND Academies = 



