Abstract
PARIS. Academy of Sciences, October 3.—M. Léon Guignard in the chair.—J. Costantin: Alpine biology. The modifications of the fungus Pleurotus Eryngii produced by an Alpine climate.—A. Rateau: A new locking screw nut. The system described and figured is suitable only for special work in which the cost is not of first importance. It permits an adjustment of the screw to 1/240th of a turn, with an absolutely safe lock.—G. Giraud: Non-linear partial differential equations of the second order of the elliptical type.—M. Drouin: Contribution to a general study of unlimited algorithms.—O. Cahen: A new aerial float. The use of an evacuated rigid envelope (sheet aluminium on a wooden framework) is suggested in place of a non-rigid balloon filled with a light gas.—L. Rodes: Does the earth exercise an influence on the formation of sun-spots?—E. Perucca: The Volta effect in a vacuum and in highly rarefied gases. The couples studied included Zn|Hg, Cd|Hg, Bi|Hg, and Sb| Hg, the experiments with the Zn|Hg couple being given in detail. There would appear to be a Volta effect in the absence of a superficial gas layer, —0.17 volt for Zn/Hg. Water vapour exerts no special influence On the voltages, but the effect of oxygen, even when dry, is very marked.M. Curie: The action of the infrared rays on phosphorescence. According to a recent theory of Ives and Lukiesh, there should be a diminution in the intensity of the X-rays reflected from the no-face of a crystal of cubic blende when infra-red radiation is allowed to fall on the face of the crystal. The experiment has been made by the author, with a negative result.
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Societies and Academies. Nature 108, 263 (1921). https://doi.org/10.1038/108263a0
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DOI: https://doi.org/10.1038/108263a0