Societies and Academies

Abstract

LONDON. Faraday Society, July 7.—Sir Robert Robertson, president, in the chair.—G. R. D. Hogg: A note on the conduction of heat down the necks of metal vacuum vessels containing liquid oxygen. Approximate methods are given for calculating the “neck loss “of metal Dewar flasks containing liquid oxygen. These may also be used for determining the most suitable dimensions for the inner neck of a metal Dewar flask, the other dimensions of which are known.—C. L. Haddon: The mechanism of setting of calcium sulphate cements. There are fundamental differences in the hydration processes between plaster of Paris, flooring plaster and anhydrite. Further evidence in favour of Desch theory of crystal thrust as the cause of expansion is put forward. There is a similarity between the coherence of calcium sulphate cements and that of metals.—J. J. Doolan and J. R. Partington: The vapour pressure of tellurium. The vapour pressure of sulphur has been determined in various ways, and at least one determination of that of selenium has appeared. The vapour pressure of tellurium, however, has, apparently, not previously been measured. Its value, at least approximately, has been determined at different temperatures.—E. E. Turner and W. H. Patterson: Cryoscopy in sodium sulphate decahydrate. The molecular weights of a number of sodium salts have been determined, using sodium sulphate as cryoscopic solvent, a method first investigated by Lowenherz, whose results have, in general, been confirmed. Abnormal results were obtained for the molecular weights of sodium oxalate and borax. The low result for the former substance is not due to solubility effects, whilst the molecular weight obtained for borax is in good agreement with the value obtained by Boutaric, Chauvenet, and Nabot, using sodium thiosulphate as solvent.—D. B. Macleod: The viscosity of binary mixtures.—J. B. Firth and F. S. Watson: The catalytic decomposition of hydrogen peroxide solution by animal charcoal; the production of highly active charcoals.—A. J. Allmand and A. N. Campbell: The electro-deposition of manganese. The best conditions for the electro-deposition of pure manganese consist in the electrolysis of a solution containing manganous and ammonium sulphates (the catholyte) separated by a diaphragm from the anolyte (ammonium sulphate solution), the H. concentration being kept at 10″6 to 10″8 by the regulated addition, as required, of sulphuric acid or of ammonia. The temperature is 300 C. and the current density at the cathode 10-15 amps./d.m. The rotating aluminium cathode has a burnisher lightly pressing against it. Electrolyte manganese contains a considerable quantity of dissolved hydrogen, which is not, however, responsible for its brittle nature.—J. Grant: Concentration-cells in methyl alcohol. Part II. Solutions containing tetraethyl ammonium iodide.—F. H. Jeffery: The electrolysis of solutions of potassium oxalate with a tin anode, and an electrometric determination of the constitution of the complex anions formed. Electricity passes from anode to anolyte in accord with the equation