Abstract
PARIS. Academy of Sciences, August 8.—M. Leon Guignard in the chair.—A. Demonlin: Surfaces generated by circles.—P, Falou: The domains of existence of certain uniform functions.—M. Potron: The representation of the group of 27 right lines in a group of quaternary collineations.—K. Ogura: The movement of a particle in the field of a charged nucleus.—L. Dunoyer: A new spectrum of caesium. The metal was contained in a quartz tube, with plane parallel quartz ends, and surrounded with a wire spiral in which high-frequency currents were produced. The whole could be heated uniformly in an electric furnace. The vapour commenced to be luminous at 100° C., reaching a maximum luminosity at 250° C. The spectrum consists of fine lines with no trace of a continuous background. Measurements of more than 300 wave-lengths for the low-temperature spectrum are given.—S. Procopiu: Magnetic double refraction of mixed liquids and crystalline structure.—E. Moles and F. Gonsalez: A new revision of the density of oxygen gas. Special attention has been paid to varying the method of preparing the gas, and density measurements are given for oxygen prepared from potassium permanganate, potassium chlorate, mercuric oxide, and silver oxide, and by the electrolysis of water. The general mean is 1-42889, differing only by one part in 10,000 from the figure at present accepted, 1-42905. The densities, classified according to the method of preparation, showed no sign of any systematic error.—A. Mailhe: The preparation of a petrol from a fatty oil. Linseed oil was passed over a catalyst composed of copper, magnesia, and kaolin heated to 550°–650° C. The volatile product was ftirther treated with hydrogen and reduced nickel at 180° C. After refining, petrol and kerosene fractions were obtained. The petrol contained benzene and naphthene derivatives.—G. Vavon: The velocity of the reaction in the hydrogenation by platinum black. The rapidity with which the hydro-genated body formed leaves the surface of the catalyst is a governing factor in the velocity of the reaction.—V. Yeramian: The synthesis and dehydration of ethylpropylphenylcarbinol. Ethylpropylphenylcarbinol was prepared by the Grignard reaction from propyl-phenylketone and ethylmagnesium bromide. This can be distilled without decomposition under low pressure (25 mm.), but is readily dehydrated, producing an un-saturated hydrocarbon, C12H16, probably 3-phenyl-3-hexene.—V. Liibimenko: The state of chlorophyll in the plasts. A study of the causes of the inactivity, from the point of view of photosynthetical reactions, of pure chlorophyll prepared by chemical methods. It was found that treatment of the living tissue by various solvents, besides coagulating the proteid^ substances in the plasts, produces sensible changes in the optical properties of the green pigment. The chlorophyll of the leaves of Aspidistra elatior can be completely removed by extraction with water. The absorption spectrum of the material thus extracted is absolutely identical with that of the living leaf. The chlorophyll is intimately related to the proteid substances of the plasts, and this is probably of a chemical nature.—M. Romien: The crystalline inclusions of the eleocytes of Nereis and their relations with the eosinp-phil granulation.—C. tevaditi: Embryonic leaflets in relation to pathogenic micro-organisms. Meso-dermic infections are caused by bacteria, fungi, spirillæ, and protozoa, whilst infections of the ectoderm are produced by virus, usually invisible and capable of passing filters.
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Societies and Academies. Nature 107, 831–832 (1921). https://doi.org/10.1038/107831b0
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DOI: https://doi.org/10.1038/107831b0