Abstract
PARIS. Academy of Sciences, January 24.—M. Georges Lemoine in the chair.—The president announced the death of M. Georges Humbert, member of the Academy.—P. Termier and L. Joleaud: The age of the phenomena of transport in the mountains of Gigondas (Vaucluse).—G. Gouy: A theorem of geometrical optics and its application to systems of prisms.—M. Pierre Bazy was elected a member of the section of medicine and surgery in succession to M. Guy on.—J. Andrade: The transverse elastic displacements of the centre of gravity of a cylindrical spiral and its doublets.—C. Féry: A mechanical clock with free escapement.—A. Liénard: The electromagnetic energy and thermodynamic potential of a system of currents.—G. Reboul: A new property of bodies poor conductors of electricity. An attempt to discover the causes of phenomena described in an earlier communication.—M. Collignon: The propagation of the sound of guns to great distances. The annual periodicity. Confirmation of results given in a previous communication: the law of annual periodicity has been verified up to November 18, 1918.—L. Forsén: The systematic nomenclature and constitution of the derivatives of molybdic acid. Representing molybdic acid by the formula H6Mo3O12.(3H2MoO4), the composition of the complex salts of molybdates can be satisfactorily represented.—E. Rengade: The isothermal concentration of a solution prepared starting with two salts with different ions. A study of the compositions of the solution and deposited salts produced by the isothermal evaporation at 25° C. of a solution of ammonium nitrate and sodium chloride.—Mlle. J. Bonnefoy and J. Martinet: 6-Methylisatin. Two new methods are given for the preparation of this compound, the first starting with metatoluidine and methyl mesoxalate, and the second with metatoluidine, carbon bisulphide, and hydrogen peroxide.—E. E. Blaise: Derivatives of 1:4-diketones and semicarbazide. The primary product of the reaction between the diketone and semicarbazide is a disemicarbazone; this is readily converted in formic acid solution into an N-ureo-pyrrol.—G. Mignonac: A new general method for the preparation of amines, starting with aldehydes or ketones. The aldehyde or ketone is dissolved in an alcoholic solution of ammonia, finely divided nickel added, and the mixture kept violently shaken, treated with hydrogen at atmospheric pressure. Examples of the application of the method are given.—P. Glangeaud: The mountains of Margeride: their porphyric eruptions, cycles of erosion, and glaciers.—J. Savornin: The distribution and direction of the phosphate basins in western Morocco. The deposits of Beni Meskine and Oulad Delim are rich, very extensive, and of great commercial importance. The other basins described are only of theoretical interest.—A. Lumière: The harmful action of dead leaves on germination. A study of the substances extracted from dead leaves by water showed the presence of reducing substances capable of preventing the germination of seeds. Numerous successive extractions were required before these substances were completely removed. From these observations it is supposed that after the fall of the leaves rain-water extracts these harmful substances during the winter, thus partially sterilising the soil and removing oxygen, and it is only after the lapse of a certain period of time that sufficient oxygen is present in the soil to permit the germination of seeds.—G. Tanret: The presence of quinic acid in the leaves of some conifers. The leaves of the cedar collected in July contain 5 gm. of quinic acid per kg. of dried leaves. Similar results were obtained with larch leaves, but the examination of other conifers gave no quinic acid.—A. Magnan: The action of the wrater on the body and head of diving birds.—C. Dekhuyson: The biological semi-permeability of the external walls of the Sipunculideæ. Experiments are described which show that the external walls of Phascolosoma vulgare and Sipunculus nudus are semi-permeable in so far as pure water, carbon dioxide, and oxygen pass through with much greater velocity than salts in solution.—P. Goy: The lower plants and the accessory factors of their growth. From studies of the growth under varying conditions of several species of yeasts, moulds, and bacilli, the conclusion is drawn that vitamines are not indispensable to the lower plants, but that their evolution is considerably influenced by the presence of an organic body which has been isolated in a pure crystallisable state from cultures of Mucor mucedo. This substance is not an amino-acid, and contains neither nitrogen nor phosphorus.—H. Bierry and F. Rathery: Diabetes and glycemia.
Article PDF
Rights and permissions
About this article
Cite this article
Societies and Academies. Nature 106, 818 (1921). https://doi.org/10.1038/106818a0
Published:
Issue Date:
DOI: https://doi.org/10.1038/106818a0