Abstract
PARIS. Academy of Sciences, October 6.—M. Léon Guignard in the chair.—H. Deslandres: Remarks on the constitution of the atom and the properties of band spectra. A continuation of communications previously made on the same subject. Band spectra may be considered as being formed of transversal and longitudinal vibrations, but the exact part of the spectrum which can be attributed to the one or the other of these cannot as yet be precisely determined.—G. Charpy and J. Durand: A cause of rupture of steel rails and a means of suppressing it. It has been proved by several observers that a frequent cause of breakage of steel rails, not possessing any local faults due to manufacture, consists in the formation of very fine fissures appearing on the surface carrying the wheel after a certain period of use, and it has been proposed that, after a careful inspection of the permanent way, these fissured rails should, be detected and removed. The critical age of steel rails appears to be about ten years. The author has found that the incipient cracks are removed by annealing, and suggests a method by which it would be possible to annealthe rails without removal from the track.—E. Ariès: The equation of state of ethyl formate.—G. A. Boulenger: The genus Saphseosaurus, a Rhynchocephalian of the Kimmeridge formation of Cerin. The examination of the specimens at the Lyons Museum leads the author to agree with the views of L. Lortet as to the classification of this reptile, as opposed to the interpretation of D. M. S. Watson.—N. E. Nörlund: An extension of the polynomials of Bernoulli.—M. Stoïlow: The analytical representation of functions of several complex variables.—G. Serf: The transformations of linear partial differential equations with two independent variables.—J. Rey: The experimental predetermination in the laboratory of the characteristic of a lighthouse at the horizon. The distribution of the light intensity in the horizontal plane is studied by means of a series of metallic screens, pierced with a regular series of small holes of accurately known diameter. The results of such a study are shown in a graph.—Ch. Boulin and L. J. Simon: The action of stannic chloride on dimethyl sulphate. The products of the reaction at a temperature of a!sout 114° C., the boiling point of stannic chloride, are methyl chloride and stannic sulphate.
Article PDF
Rights and permissions
About this article
Cite this article
Societies and Academies . Nature 104, 271 (1919). https://doi.org/10.1038/104271a0
Issue Date:
DOI: https://doi.org/10.1038/104271a0