Societies and Academies

Abstract

PARIS. Academy of Sciences, October 10.—M. Émile Picard in the chair.—The president announced the death of M. Treub, correspondant in the section of botany, and of Ernst von Leyden, correspondant in the section of medicine' and surgery.—Henri Douvillé: The formation of the loam of the plateaux. This loam, consisting of a very intimate mixture of clay and fine sand, is well developed in the neighbourhood of Paris and in the north of France. Two hypotheses have been put forward to explain its formation, deposition from water and transport by wind. The former hypothesis is shown to be in better accord with the observed facts; to explain the height above the sea at which these deposits are found, the floods carrying the deposits are supposed to have been caused by the sudden melting of snows, the lower portion of the valley being blocked by glacier.—Serge Bernstein: A generalisation of the theorems of Liouville and Picard.—F. Robin: The law of resistance to crushing of cylindrical bodies as a function of their dimensions. The general law of resistance to crushing as a function of the dimensions of the test-pieces is expressed geometrically by a hyperbolic paraboloid.—H. Pelabon: Batteries with antimony and antimony selenides. An element formed of antimony and antimony selenide, with an acid solution of antimony trichloride as the electrolyte, shows varying electromotive force under the action of light. If sulphur or tellurium is substituted for the selenium the phenomena described are not produced. The effect is strongest when the element is exposed to the yellow and red rays.—G. Charpy and S. Bonnerot: The reduction of oxide of iron by solid carbon. Ferric oxide and graphite, intimately mixed, were heated in a vacuum at temperatures up to 950° C., and the reaction studied by measuring the amount of gas evolved per hour. The speed of reaction diminished as the pressure maintained in the apparatus was reduced, and became practically zero when the pressure in the tube was of the order of 0.001 mm. of mercury. Hence it is concluded that solid carbon does not reduce oxide of iron at 950° C.—P. Mahler and J. Denet: The presence of a small quantity of carbon monoxide in the air of coal mines. The amounts found varied between 0 and 40 volumes per million, with an average of 19. The maximum amount of carbon monoxide corresponded with the minimum of methane, and the maximum methane was found in the sample containing no carbon monoxide.—Paul Vuillemin: A natural preventa-tive to the oak-tree disease. The disease of the oak, caused by an Oidium, is kept in check by a Cicinnobolus, a parasite preventing the multiplication of the Oidium by cpnidia, and its preservation by the mycelium.—E. L. Trouessart: The mammalian fauna of Europe.—Ch. Gravier: The coral reefs of the Gulf qf Aden and their madrepores.—Paul Marchal: Contributions to the biological study of Chermes.—Edouard Chatton The existence of Dinoflagellæ, coelomic parasites. Syndinium in the pelagic copepods.—A. Fernbach and E. Vulquin: The microbicidal power of macerations of yeast and cereals. The poison elaborated by yeast is not identical with that obtained from cereals.—A. Briquet: Geology of the Gallo-Belgic region.