January 4, 1900] 



NA TURE 



239 



at all, but a particular and very limited kind of strain, which 

 consisted oPa' simple rotation combined with an isotropic expan- 

 sion, and thus involving four constants only. Klein and Som- 

 inerfeld's attempted identification of Gauss' operator with 

 Uamilton's quaternion indicated a curious misapprehension on 

 heir part of Ihe real essence of a quaternion. — Dr. C. G. Knott, 

 !, \ paper on the same subject, gave a detailed criticism of the 

 ection in Klein and Sommerfeld's treatise devoted to the 

 'iscussion of the theory of quaternions. 



Paris. 

 Academy of Sciences, December 26, 1899. — M. van Tieg- 

 hem in thechair. — M. H. Milne Edwards waselected Vice-Presi- 

 dent of the Academy for the year 1900. — Note on the work con- 

 lined in the volume of the " Annales de I'Observatoire de Paris 

 ie 1897," by M. Loewy. This volume inaugurates a new series of 

 lunales, differing from preceding volumes both in the nature of 

 I he work carried out and the form chosen for publication — On 

 the radiation of radio-active bodies, by M. Henri Becquerel. 

 There would appear to be a fundamental difference between the 

 : idiations of radium and polonium salts, in spite of their similar 

 hotographic action, as the polonium radiations placed in a 

 lagneiic field show no influence of the same order as observed 

 t radium. ^-Experimental cultures on the adaptation of plants 

 ' the Mediterranean climate, by M. Gaston Bonnier. The 

 'iject of these researches was to find out if plants 

 iken from temperate climates to the Mediterranean 

 . >uld so modify their form and structure as to adapt 

 themselves to their new surroundings. Experiments were 

 c.irried out with a large number of different species, and 

 nearly all showed, even after one season, notable differences 

 in .form, the stems becoming more ligneous, even stems of 

 one year's growth, the leaves larger and thicker with the veins 

 cuore strongly marked. — Researches on the tautomerism of 

 benzoyl-benzoic acid, by MM. A. Haller and A. Guyot. From 

 ■its mode of formation from benzene and phthalyl chloride, 

 benzoyl-benzoic acid would appear to have the constitution of 

 -.in oxylactone, and this view is confirmed by the formation of 

 <liphenyl-phthalide from its chloride. But, on the other hand, 

 on many reactions both the chloride and acid exhibit undoubted 

 ketonic properties. It thus appeared to be interesting to see if 

 ihe tautomeric modifications of this acid could be obtained as 

 'iiethyl ethers. Methyl-o-benzyl benzoate was accordingly pre- 

 ired by five different methods, direct etherification by 

 i\drochloric acid, interaction of methyl iodide and the 

 ilver salt, interaction of benzoyl -benzoic anhydride and 

 HJium methylate, action of sodium methylate upon acetyl- 

 cnzoyl-benzoic anhydride, and upon benzoyl-benzoic chloride. 

 In all cases the same ether was produced, which would 

 appear to be the trueketonic ether, CbH.,.CO,C6H4.CO.(OCH.,). 

 — Remarks by M. Albert Gaudry, upon a work of M. Erland 

 Nordenskjold. — General Gallieni was elected a correspondent 

 for the Section of Geography and Navigation. — Observation of 

 the eclipse of the moon of December 16, 1899, with the photo- 

 graphic equatorial at Toulouse, by M. Montangerand. Ex- 

 periments with plates of different degrees of sensitiveness showed 

 »hat panchromatic plates give better results with a total than a 

 partial eclipse. — Observations of the new planet EV (Charlois), 

 made at the Observatory of Besan^on, by M. P. Chofardet. — 

 Organisation of the daily registration of the entire chromosphere 

 of the sun ac the Observatory at Meudon. First results, by 

 M. H. Deslandres. — Remarks on the preceding communication, 

 tiy M. J. Janssen. — On the employment of triphase currents in 

 Radiography, by M. Delezinier. — On the discontinuities pro- 

 •duced by the brusque expansion of compressed gases, by M. 

 i'aul Vieille. Diaphragms of collodion were constructed 

 ^capable of standing a pressure up to twenty-seven atmospheres. 

 By the sudden rupture of this diaphragm, an explosive 

 wave was set up, the front of which was more 

 .symmetrical than when explosives are used. The mean veloci- 

 .ties of propagation of the wave were measured at different 

 distances from the diaphragm. Velocities could thus be ob- 

 tained of over 600 metres per second, greater than the velocity 

 of sound. — On some phenomena presented by iron, by M. 

 •Galy-Ache. The results of the experiments upon a very pure 

 .sample of iron are in accord with the views of Osmond and 

 Werth, that there are two allotropic varieties of iron, o iron, 

 stable at the ordinary temperature, and yS-iron, stable at high 

 temperatures. — On the changes in volume accompanying the 

 •hardening of hydraulic cements, by M. H. Le Chatelier. The 



^'o ^575- '^'OL. 61] 



contraction was measured by sealing up the cements in the bulb 

 of a thermometer containing water. The absolute contrac- 

 tion after six months was between 4 c.c. and 5 c.c. per 

 100 grams of cement. There was at the same time an 

 apparent expansion, sufficient in some cases to burst the 

 bulbs of the thermometers.— On the temperature of transforma- 

 tion of[the two varieties, quadratic and orthorhombic, of mercuric 

 iodide, by M. D. Gernez. The transformation-temperature 

 is 126°. The temperature of 75°, found by M. Wyrouboft", is 

 due to an error caused by his working in vacuo. — New experi- 

 ments upon the activity of manganese with respect to the 

 phosphorescence of strontium sulphide, by M. Jose Rodriguez 

 Mourelo. — On molybdenum silicide, by M. E. Vigouroux. 

 Silicon combines directly with molybdenum in the electric fur- 

 nace, forming Mo.^Sis, which is obtained pure with difficulty. 

 It burns in chlorine at 300°, giving silicon tetrachloride and 

 molybdenum perchloride. — On molybdenum disulphide, by M. 

 Marcel Guichard. Of the various methods suggested for the 

 preparation of molybdenum disulphide, two only are satis- 

 factory, the fusion of potassium carbonate and sulphur with 

 molybdenum dioxide, and heating sulphur to a high temperature 

 with ammonium molybdate. The first method gives a crystalline 

 product, the second an amorphous one. By the action of heat a 

 new sesquisulphide is formed, further particulars of which will 

 be given in a subsequent note. — The action of nitrous acid upon 

 the leucobase Cj^HjiN,,, by M. A.Trillat. — Heat of neutralisa- 

 tion and acidimetry of cacodylic acid, by M. Henri Hibbert. 

 Cacodylic acid is a feeble monobasic acid, being neutral to 

 helianthine and monobasic to phenol-phthalein. — The hydrate 

 of sodium dioxide and the prepration of hydrogen peroxide, 

 by M. de Forcrand. — On the anhydrous sesquichlorides 

 of rhodium and iridium, by M. E. Leidie. The double 

 chloride RL^ClgdNaCl. (with sH^O or iSHgO), heated in 

 a current of dry hydrogen chloride up to 440° C gives a mixture 

 of Rh.iClg and NaCl from which the latter can be removed by 

 washing with water. The hydrogen chloride may advantage- 

 ously be replaced by chlorine if the double salt is previously 

 dried at 105°-! 10° C. The corresponding iridium chloride is 

 best obtained by heating Ir2Clg6NH4Cl in chlorine at 440° C.— 

 The biochemical oxidation of propylglycol, by M. Andre Kling. 

 Following up his previous v\ork on this subject, the author has 

 now proved that the reducing body formed by the oxidation of 

 CH2(OH)CH(OII)CH3 is acetal, CH3.CO CH2OH.— On the 

 preparation of the carbazides. Action of the hydrazines upon the 

 phenolic carbonates, by M.\l. P. Cazeneuveand Moreau. By the 

 interaction of phenyl carbonate and phenyl-hydrazine a good yield 

 of carbohydrazide is obtained. Similarly hydrazine hydrate 

 gives carbazide, C0(NH.NH.^)2. The method appears to lie 

 capable of general application. — Combinations of lithium 

 chloride with ethylamine, by M. J. Bonnefoi. From the dis- 

 sociation pressures of the compounds LiCI.C^HjlNHj), 

 LiC1.2C2H,(NH2), LiC1.3C2Hs(NH„), the heats of dissociation 

 are calculated by Clapeyron's formula to be 1372 cal. , 1 1 09 

 cal., and 10 50 cal. The.se numbers were also measured directly 

 in the calorimeter, and found to be I3"83 cal., ip"98 cal., and 

 lO'57 cal. respectively. — On narceine, by M. Emile Leroy. 

 Measurements of the heats of hydration, combustion, and for- 

 mation of narceine and its salts. — On the evolution of mineral 

 matter during germination, by M. G. Andre. — On the estima- 

 tion of the halogens in organic compounds, by M. Amand 

 Valeur. The determination of the halogens in organic 

 compounds can be carried out very rapidly and ac- 

 curately in the calorimetric bomb, provided that a .suit- 

 able quantity of naphthalene is burned at the same time. 

 For chlorine and bromine, strong ammonia is placed in the 

 bomb, and this liquid analysed volumetrically either by Mohr's 

 or Volhard's method. The whole analysis can be finished in 

 half an hour. For iodine the ammonia is replaced by potash 

 solution. Tetra iodo-ethylene, containing 95*5 per cent, of 

 iodine, gave very good results by this method. — On some effects 

 of electric discharges upon the heart of mammals, by MM. J. L. 

 Prevost and F. Battelli. Under the influence of a current of 

 suitable strength, the tremulous vibrations are replaced by true 

 rhythmic contractions of the heart, with restoration of the blood 

 pressure, if the current is applied within fifteen seconds of the 

 appearance of the trembling. — General considerations on the 

 male reproductive organs of the Coleoptera, by M. L. Bordas. 

 —The evolution without heterogony of an Angiostome of the 

 ringed adder, by M. Railliet.— On the pigment of the 

 Arenicolae, by M. Pierre Fauvel— Chlorophyllian assimi- 



