Abstract
PARIS. Academy of Sciences, Dec. 10.-Maurice Hamy: A consequence of a property of diffraction by a circular aperture.-Charles Moureu, Charles Dufraisse, and Marius Badoche: Autoxidation and antioxygen action. (33) The catalytic properties of antimony, bismuth, and their derivatives, and of some vanadium derivatives. The experimental results are summarised in eight diagrams. The catalytic properties of vanadium compounds were very marked.-L. Cayeux: The existence of fresh-water spongoliths in the Gard coal basin. The ' silex ' of Doulovy is composed of spongoliths, exceptionally rich in spicules, and proves the existence of fresh-water sponges at a very remote period.-Gabriel Bertrand and Boje Benzon: The proportions of zinc in plants used for food. The leaves of plants contain zinc in amounts which increase with the proportion of chlorophyll present. Bulbs (garlic, onion) and seeds contain the highest percentages of zinc.-Riquier: A problem relating to the partial / g2 2 \ differential equation (a~s+5~2) u -f(x> V)--Jean \ox cy J Baptiste Senderens: The catalytic dehydration of alcohols by alkaline bisulphates. Several d ehydrations hitherto carried out with potassium bisulphate can be effected with greater facility with sodium bisulphate. Details of the preparation of cyclohexene from cyclohexanol are given.-Charles Nicolle, Charles Anderson, and Jacques Colas-Belcour: The experimental adaptation of recurrent spirochsetes to species of Ornithodora other than those which transmit them in Nature. The necessary conditions for success in these experiments are that nymphs must be used, since although adults can be infected they are incapable (with rare exceptions) of transmitting the spirochsetes by their bites, and to utilise for the infecting meal an animal the blood of which is rich in spirochsetes.-Serge Bernstein was elected Correspondent for the Section of Geometry.-Paul Delens: The calculus of spherical operations.-Marcel Vasseur: The deformation of a surface with a conical conjugated network.-Pierre Rivet: The contact of skew curves and of surfaces.-Mandelbrojt: A generalisation of a theorem of M. Hadamard.-Florin Vasilesco: The nature of irregular and regular points and their distribution on the frontier of a domain.-Belzecki: Some cases of equilibrium of elasticity of a rectangular prism.-D. Pompeiu: A formula generalising Cauchy's integral and its interpretation in hydrodynamics.- Henri Benard: Alternate vortices and the law of dynamic similitude.-G. P. Arcay: The influence of vibrations on the rate of chronometers. Vibrations bring about a change in the rate of the chronometer, usually a retardation, and part of this change in rate is permanent. The results of the experiments are given in detail.-Josef Mikulas Mohr: The law of frequencies of the velocities of stars and the relation between the absolute magnitude and absolute velocity for Cr-type stars. The distribution of the frequencies of the absolute velocities of these stars, found by the author for 519 stars, is in agreement with the law of Adams, Stromberg and Jay, resulting from the study of type K.-R. Jarry-Desloges: The period of the planet Venus. The figure deduced is 23 hours 53 minutes, but this result is approximate only, since it implies no change in the markings on the planet during a terrestrial day.-E. Pierret: Oscillators with very short waves.-G. Grenet: The Hughes induction balance for the determination of the susceptibility of rocks. By the use of the methods and apparatus of wireless telephony, the sensitiveness of the Hughes induction balance can be increased to & marked extent. The apparatus requires some tedious preliminary adjustments, but once set up, the determination of the magnetisation coefficient of a rock can be completed in five minutes.-Paul Soleillet: The theory of the polarisation of light emitted by fluorescence.-Mile. Jacqueline Zadoc-Kahn: The refractive indices of a mesomorphic substance in the solid state. Details of the measurements of the three principal refractive indices of crystals of para-azoxyanisol. From the results, this is one of the most strongly doubly refractive substances known.-R. Coustal: The permanent luminescence of certain crystallised salts of uranium. Uranium salts have a faint permanent luminosity, visible only after the eye of the observer has been in complete darkness for thirty minutes or longer. The effect is shown most strongly by the sulphate, the nitrate rather less, acetate and other salts much less. The explanation is based on energy derived from the radioactivity of the uranium.- Pierre Auger: The directions of emission of the photoelectrons.-A. Boutaric and M. Doladilhe: The electrosmosis of mixtures of electrolytes.-Pierre Jolibois and Pierre Montagne: A rapid method of calculation of homogeneous dissociations. Application to carbon dioxide. A graphical method is described and illustrated.-Lecorche and Jovinet: Study of the mechanism of the stabilisation of nitroglycerol powders by diethyldiphenylurea. As soon as the powder becomes acid, the nitrous acid formed is absorbed, giving ethylphenylnitrosamine; the latter can be readily determined by a colour method based on the reaction with ct-naphthylamine and hydrochloric acid.-Albert Portevin: The action of sulphur dioxide at high temperatures on glasses and basic rocks and a probable origin of sulphate mineral springs. Sulphur dioxide, even when diluted with other gases, at high temperatures attacks basic rocks and glasses superficially, forming the sulphates of the alkalis and alkaline earths. The attack is selective, as in spite of the low proportion of sodium in the rocks attacked, the deposit consists mainly of sodium sulphate.- J. Fallot: The northern limit of the subbetic over-thrusts between Sierra Sagra and Rio Segura.-Leon Moret: The extension of the strata containing Hemithersitea and phosphate in the southern slope of the Marrakech Atlas (Morocco).-Aug. Chevalier: The origin of the Imbuia wood (Brazilian walnut) of Brazil and the biology of the producing tree, Phosbe porosa, belonging to the Lauracese family.-Pierre Dangeard: The favourable action of potassium iodide on iodovolatilisation. The emission of free iodine by certain algss is increased by treatment with sea water containing a small proportion of potassium iodide in solution.-Paul Guerin: Hydrocyanic acid in lotus. A discussion of the amount of hydrocyanic acid present in varieties of Lotus, with reference to possible danger as fodder.-Serge Yourievitch: The energetics of the ocular movements.-G. Hamel and J. Feldmann: The geographical distribution of the Fucaceae and Laminaria on the western coasts of the Iberian peninsula.-A. Magnan and A. Sainte-Lague: The experimental determination of the resistance to the forward motion of fishes. The results of a kine-matographic study giving true velocities.-S.Posternak: A new organic phosphorus compound in the red blood corpuscles. The new compound is probably a di-phosphate of a-ketotrioxyadipic acid.-Y. Manouelian and J. Viala: The spinal marrow, the bulb, the protuberance, and the parasite of hydrophobia.- Et. Burnet, P. Durand, and D. Olmer: Marseilles exanthematic fever is absolutely distinct from exan-thematic typhus fever. The Marseilles fever does not give immunity against typhus (in the ape), and acquired immunity against typhus does not prevent the development of Marseilles fever, thus proving that the two diseases are distinct.-Camille Nachet: A new arrangement for the simultaneous registration of three selected images for the production of photographs in colour.
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Societies and Academies . Nature 123, 113–115 (1929). https://doi.org/10.1038/123113b0
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DOI: https://doi.org/10.1038/123113b0