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PARIS. Academy of Sciences, June 11.—P. Villard: The reduction of soda by hydrogen. Caustic soda, heated in a current of hydrogen at 800°-900° C, gives sufficient sodium vapour to reverse the sodium lines and to cut off all the light from a sodium flame. This result cannot be due to dissociation, since at the same temperature the replacement of the hydrogen by nitrogen causes the sodium vapour to disappear.—Louis Roy: The propagation of waves on elastic surfaces with three parameters.—Paul VuHlemin: A new species, Gorethropsis Puntonii.—O. Boruvka: The surfaces represented by spherical functions of the first species.—Ch. Sadron: The ferromagnetism of the alloys of nickel and chromium. The study of the magnetic properties of nichrome alloys has been made by Safranck. On the same specimens the author has studied the saturations at the absolute zero and the ferromagnetic Curie points.—Leon Bertrand: The Trias of the neighbourhood of Betchat and of Salies-du-Salat June 16.—Leon Lecornu: Funicular surfaces.—V. Grignard and J. Colonge: The condensation of ketones. Extension of the classical method. The substitution of hydrochloric acid by hydro-bromic and hydriodic acids gives higher yields, and some ketones which resist the condensing action of hydrochloric acid suffer condensation in the presence of hydrobromic acid.—Leon Guillet and Marcel Ballay: The influence of tempering on the electrical resistance and resistance to shearing of the silicon-aluminium alloys. The electrical resistance of pure aluminium.—Jean Rey was elected a member of the division of the applications of science to industry.—L. Abeles: The nomographie representation of analytical functions. Application to complex trigonometry.—Mme. Julie R6zanska: The continued decompositions of surfaces into Cantorian curves.—Andre Roussel: Functions the infinitesimal increase of which has a given expression.—Marcel Winants: Linear differential equation of the third order and the integral curve passing through three given points. O.M. Fekete: The changes of sign of a continuous function in an interval.—Vignaux: A method of summation of divergent integrals.—H. E. Bray: Functions with finite deviation.—P. J. Myrberg: The existence of Green's function for a given plane domain.—G. Maneff: Gravitation and the energy at the zero.—Al. Proca: Dirac's equation.—N. Stoyko: The influence of the terms of the third and fourth orders in the use of E. Esclangon's method for the determination of the orbit of a star. Application to the trans-Neptunian body.—Ernest Esclangon: Remarks on the preceding note.—Fernand Baldet: The nucleus of the Schwassmann-Wachmann eomet (1930d). The nucleus does not appear to have had a diameter much greater than 400 metres, and is at least as small as that of the Pons-Winnecke comet.—L. Decombe: The undulatory theory of quantic phenomena. New results.—F. Holweck and P. Lejay: A portable instrument for the rapid determination of gravity.—H. Muraour and G. Aunis: The agreement between calculated explosion pressures and experimental explosion pressures. The calculated explosion pressures, starting with the new specific heats of Nernst and Wohl, for the gaseous mixture obtained in the experiments, are in complete agreement with the experimental pressures corrected for cooling.—R. Forrer and J. Schneider: The production by annealing of two states of pure iron, stable at the ordinary temperature.—Armand de Gramont and George Mabboux: The comparison of piezoelectric quartz oscillating at slightly differing frequencies.—L. Abonnenc: The measurement of the magnetisation coefficient of aqueous solutions by the method of falling drops. The method has been applied to measure the diamagnetism of the halogen ions. The results are in good agreement with the values obtained by Hocart by a different method.—A. Turpain and R. de Bony de Lavergne: An ultramicroscope permitting the direct projection of ultramicroscopie tests and the Brownian motion.—V. Fock: The mechanics of the photons.—F. Prevet: The mode of action of boric acid on the phosphorescence of sulphides of zinc prepared by the explosion method. The use of boric acid in the preparation of phosphorescent zinc sulphide is known to increase the intensity and persistence of the phosphorescence. Attempts to replace boric acid by other substances have proved unsuccessful, and it is concluded that the boric anhydride acts by influencing the crystalline medium necessary for phosphorescence.—R. Coustal: Poisons and phosphorogens for phosphorescent zinc sulphide.—E. Estanave: Integral photographs obtained without objectives.—Hubert Garrigue: The passage of the continuous current in acetone.—Georges Fournier: A relation between the filiation capacity of radioactive atoms and the velocity of the a-rays which they emit.—Augustin Boutaric and Mile. Madeleine Roy: The radioactivity of materials arising from old roofs. The radioactivity of substances exposed to the open air is not due to exposure to sun, but to contact with rain water. Rain water was collected on a roof and passed into a cistern containing a filter of sand and charcoal, the filtering material not being exposed to the sun: both the charcoal and the sand were clearly radioactive.—W. Broniewski and J. Strasburger: The structure of the copper-zinc alloys. The brasses were examined after long periods of annealing at 400° C. Curves are given showing the electrical conductivity, the temperature coefficient of the electrical resistance, the thermoelectric power with reference to lead and other physical properties. The compound CuZn appears on all the curves and there are indications of CuZn2 and CuZn6.—H. Colin and A. Chaudun: The complex between the enzyme and the products of hydrolysis during the diastatic inversion of sugar.
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Societies and Academies. Nature 126, 225–228 (1930). https://doi.org/10.1038/126225a0
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DOI: https://doi.org/10.1038/126225a0