Societies and Academies

Abstract

PARIS. Academy of Sciences, Sept. 29.—E. L. Bouvier: A new type of ceratocampian Saturnioid.—Mile. Marie Charpentier: The Peano points of a differential equation of the first order.—Paul Montel: Some consequences of Rolle's theorem.—A. Rosenblatt: Linear equations with total differentials.—Miron Nicolesco: The extension of the theorem of Gauss to harmonic functions of p order.—Podtiaguine: The upper limit of the canonical product of infinite order.—L. Escande and M. Teissie-Solier: The chronophotographic study of the flow [of a fluid] round a plate normal to the current. The velocity measured on the surface of discontinuity is constant and equal to the velocity at infinity, agreeing with that indicated by theory. The velocities found esperimentally at various points give a law of retardation in good agreement with the theoretical law.—L. Goldstein: The principle of exclusion and intramolecular statistics.—Pierre Chevenard and Albert Porte vin: The secondary tempering of hyper-tempered steels and the stability of austenite.—Jean Lugeon: Simultaneous investigation by atmospherics at Zurich and in the Sahara. On the basis of three years' records, the following conclusion can be drawn: out of every 100 atmospherics recorded in a year, 20 per cent are of distant origin, some thousands of kilometres; 70 per cent have a range of between 100 and 1000 kilometres; 10 per cent are local, with a range of less then 100 kilometres. The Kennelly-Heaviside layer is always higher at El-Golea (Sahara) than at Zurich.—Jean Piveteau: Contribution to the study of the fossil Ganoid fishes: the family of the Catopteridese.—Louis Baudin: The variation of the respiratory exchanges of fishes as a function of the barometric pressure. By experiments at Lausanne and at Concarneau it has been established that fish are very sensitive to changes in the barometric pressure, and this sensibility is measured by large differences in the gaseous exchanges and in the respiratory coefficient.