Abstract
PARIS. Academy of Sciences, September 29.—M. Bouquet de H Grye in the chair.—New experiments on the limit of intensity of current from a battery which corresponds to external electrolytic work apparent in a voltameter, by M. Berthelot. In a circuit consisting of one or more Daniell cells and a voltameter, the external resistance was increased until the gas resulting from the electrolysis was barely perceptible, and the limiting value determined. From these and earlier experiments on the same subject, the conclusion is drawn that in electrolysis chemical energy is always necessary to commence the action, but not to maintain it. The preparation and properties of a new silicide of vanadium, by MM. H. Moissan and Holt. On heating silicon with an excess of vanadium trioxide in the electric furnace for sometime, the silicide VSi2 previously described, is obtained, which is stable in the presence of an excess of silicon. Another silicide, of the composition V2Si, has been obtained in three ways by the interaction of vanadium trioxide (120 grams) and silicon (14 grams), of silicon and vanadium carbide, or of the trioxide, silicon and copper, in all cases in the electric furnace. The new silicide is more infusible than the silicide VSi2, from which it can also be distinguished by its colour, density, action with hydrochloric acid and easy decomposition on fusion with silicon.—On double fertilisation in the Cruciferse, by M. L. Guignard. The phenomenon of double fertilisation can be followed completely in Lepidium sativum and Capsella Btirsa pastoris, a detailed description of the stages being given.—Observations of the Perrine-Borrelly comet (1902 b), made with the Briinner equatorial at the Observatory of Lyons, by M. J. Guillaume.—The organisation of automatic spectrographs at the Observatory of Meudon, registering the radial movements and the thickness of the solar chromosphere, by M. H. Deslandres. The apparatus briefly described produces on the same plate ninety small spectra giving the radial velocity and thickness, at 180 points on the sun's edge. These points are united on a circle of 95 mm. diameter. So far, it has not been possible to make continuous records on account of the expense; similar equipments at different parts of the world are also necessary for complete results.—On the continuous deformation of surfaces, by M. G. Tzitzeica.—On nitro-pyromucic acid and its ethyl ester, and on dinitrofurfurane, by M. R. Marquis. A mixture of nitric acid and acetic anhydride has been found especially serviceable in nitrating in the furfurane series. With ethyl pyromucate a mono-nitro derivative is readily obtained.—On the saponification of nitric esters, by MM. Leo Vignon and I. Bay. The results of experiments on the hydrolysis of various nitrates by sulphuric acid and by soda. The reaction is complex, nitrous acid and occasionally ammonia being produced.—On the utilisation of mineral substances by grafted plants, by MM. Lucien Daniel and V. Thomas; Transpiration is greater in the host than in the grafted plants, the total quantity of mineral material absorbed being considerably modified as a result of the grafting. It was also found that one effect of grafting was to profoundly modify the phenomenon of chlorosis.—On the caoutchouc-producing Landolphia of the French Congo, by M. Auguste Chevalier.—The earthquake at Salonica, by M. Christomanos. The earthquake of July 5, the epicentre of which was between Salonica and Gouvesno, was not of volcanic origin. Its effects were felt at great distances and for several days, hence it is probable that the seismic focus was at a great depth.
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Societies and Academies . Nature 66, 623–624 (1902). https://doi.org/10.1038/066623b0
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DOI: https://doi.org/10.1038/066623b0