PARIS. Academy of Sciences, July 20.—M. P. Appell in the chair.—Paul Sabatier and A. Mailhe: The catalytic decomposition of benzoic acid. A study of the action of various catalysts upon the vapour of benzoic acid at 550° C. With the blue oxides of tungsten and molybdenum and the oxides of zirconium and cerium the acid passes unchanged. Benzene and carbon dioxide are produced in presence of reduced copper, cadmium oxide, zinc oxide, and titanium oxide. Benzophenone is the main reaction product in presence of lithium and calcium carbonates.—H. Douvillé; The first geological epochs. A discussion of the composi tion of the earth's atmosphere at varying tempera tures of the earth's crust, with especial reference to the conditions prevailing at temperatures between 700° C. and 364° C.—Y. Delage: The capture of a specimen of Luvarus imperialis on the coast of Finistére.—A. Blondel: Electric chronographs and selfrecording micro-galvanometers. Remarks on an instrument recently described by M. Beauvais, and referring to earlier communications by the author describing a similar instrument.—Ph. A. Guye and F. E. E. Germann: The gases retained by iodine and by silver. An application of the apparatus recently described by the authors for the analysis of minute volumes of gas. The gas contained in the silver was determined by conversion into iodide in a vacuum, and the gases evolved pumped out and analysed. Oxygen, carbon monoxide, and water vapour were found.—Kr. Birkeland: The zodiacal light. A discussion of some recent observations from the point of view of the author's hypothesis, that the sun emits radiant matter and electrons, and that these corpuscles group themselves round the magnetic solar equator.—S. Stoilow: The integrals of partial differential linear equations with two independent variables.—Pierre Sève: The use of an alternating current for the transmission of the indications of apparatus of which the index can effect complete rotations. Application to the distribution of time.—G. Chaudron: The reversible reactions of water on iron and on ferrous oxide. From the experiments quoted the author concludes that between 300° C. and 1000° C. there are two series of equilibria with the solid phases iron-ferrous oxide, iron-magnetic iron oxide.—M. Delépine: The separation of the optical isomerides of the iridotrioxalates.—F. Taboury: Contribution to the study of the iron-zinc alloys. The crystals formed in baths used for galvanising iron contain a constant proportion (7.3 per cent.) of zinc.— A. Sénéchal: The solid chromic sulphates.—H. Giran: Bromine hydrate. From a cryoscopic study of mix tures of bromine and water, Br2 + 8H2O is deduced as the composition of the hydrate.—Th. W. Richards and M. E. Lembert: The atomic weight of lead of radioactive origin. According to the theory of Soddy and Fajans, the atomic weight of lead derived from the decomposition of radium and uranium should be 206.0, that from thorium, 208.4, ordinary lead being 207.1. Experiments with lead from carnotite gave 206.59, from three samples of pitchblende, 206.57, 206.40, and 206.86, one from thorianite, 206.82.—A. Desgrez and R. Moog: A method for the estimation of urea. Details of a method based on the decomposition of urea by Millon's reagent, in presence of infusorial earth. Test figures showing the accuracy obtainable are given.—R. Fosse: The gravimetric quantitative analysis of small quantities of urea for dilutions greater than 0.1 per cent. The urea is weighed as an insoluble compound with xanthydrol.—H. Gault: Oxalocitric lactone and its transformation into tricarballylic acid. The best yield of tricarballylic acid from Oxalocitric lactone is obtained by heating the latter with alcohol to 180° C.—Albert Gascard: The presence of an alcohol and an acid, both containing thirty-two atoms of carbon, in the wax of Tachardia lacca.—A. Dnfionr: An association of crystals of unequal symmetry.—C. Gaudefroy: The dehydration of gypsum.—J. Deprat: The projects for the Yun-nan-fou railway at Sseutchoan and their relations with geology. From, the geological point of view it is shown that the construction of the proposed line would offer great difficulties, and the upkeep would be onerous and costly. From an economic point of view the line would probably prove unprofitable.—V. Vermorel and E. Dantony: The chemical composition of alkaline spraying mix tures and the soluble copper which they contain. Alkaline Bordeaux mixtures, contrary to the view cur rently held, contain copper in the dissolved state.—F. Jadin and A. Astruc: Arsenic and manganese in some plant products used for animal food. Arsenic and manganese are shown to be present in fifteen plant products, and are probably normal constituents of the plant cell.—P. Mazé: The mechanism of the exchanges between the plant and the external medium.—J. Giaja: Study of reactions of two ferments working together. The hydrolysis of amygdalin by emulsin, or by the digestive fluid of Helix pomatia, is shown to be the result of two connected fermentative actions, involving the production of reducing sugar and hydro cyanic acid respectively.—Mme. Marie Phisalix: The action of the virus of hydrophobia on Batrachians and snakes.—Pierre Delbet and Armand Beauvy: Comparative study of the action of ultra-violet light on the haemolytic power and the colloidal state of blood serum.—Henri Piéron: The influence of the state of adaptation of the eye on the laws of decrease of the time of latency for various light radiations.—C. Levaditi; Hydrophobia virus and cells cultivated in vitro.—G. Marinesco and J. Minea: The infective power of the cephalo-rachidian fluid in juvenile general paralysis. This fluid has been shown to contain living spirillæ.