Abstract
PARIS. Academy of Sciences, July 25—Andrè Blondel: Abacus for the resolution og the general equation of the third degree and the discussion of the differential equation of the third order with constant coefficients. —Paul Sabatier and Antonio Feinanez: Dehyclro-genations and hydrogenation catalysed by metallic oxides. In previous communications tho catalytie behaviour of various metallie oxides has been mainly studied by the reaotions with alcohols. Piperidine has now been submitted to similar experiments. The reduction of nitrobenzene and alkyl nitrites by hydrogen in the presence of manganous oxide or zinc oxide has also been studied.—D. Wolkowitsch: A geometrical interpretation of Castigliano's theorem in a particular case.—G. Pfeiffer: The construction from a system of partial differential eqxiations of the first order with an unknown function, of an equation, linear in Jacobians, satisfying Hamburger's conditions, and also of a system of equations, linear in Jacobians, for which the generalised conditions of Hamburger are fulfilled.—Serge Bernstein: The multiply monotone polynomials which deviate the least from zero.—A. Veronnet: The most general movement of an isolated heterogeneous fluid ma,ss, which keeps an invariable form. The trajectories are circular and the level surfaces of revolution.— Swyngedauw: The xmfolcliiig of bolts.—D. S. de Lavaud; The stability of tho vibrations of the front axlo arid owheels of a, motor-car.—Rebillet: Carburation in internal combustion motors. A general formula is given for the weight of air drawn into the motor in a given time and a mechanism described and illustrated by means of which the petrol injected can bo made to follow the same law.—Léon Kirste: The practical limit to increase of size of commercial aeroplanes.—E. M. Antoniadi: Recent observations of the planet Mercury with the Meudon 83 em. telescope. —Carl Stormer: Remarkable action of sunlight on the height of the aurora borealis. On Sept. 8, 1920, the height of an aurora measured on a 26 kilometre base at Oslo was found to be 300 km.—500 km. above the earth, instead of the avcra.go 80 km.—200 km. This aurora was directly exposed to sunlight, and examination of earlier data showed that a high aurora was usual when exposed to the rays of the sun. The spectrum of the high aurora gives lines in the blue and violet which are not shown by the low altitude aurora.—H. Deslandres: Remarks on the preceding communication.—Mlle. J. Clavier: Study of the reflecting power of some unoxidisable steels. Four non-rusting steels were examined and their reflective powers measured for eight different wavelengths. One group of mirrors was exposed to the air for two months; the other group was kept away from air and moisture. The measurements were practically identical arid show that these steels possess the qualities of a good material for reflectors. —G. W. Ritchey and Henri Chrétien: Presentation of the first model of an aplanatic telescope.—Edmond Bayle and Lucien Amy: The application of spectrum analysis to the detection of metallic impurities. A modification, of the method of Jolibois and Bonnet, in which the metal is first deposited electrolytically. A list is given of the minimum amounts of various metals capable of detection by this method, varying from 1×10-6gm. of silver to 1 × 1010 gm. of manganese.—L. Dunoyer: The measurement of the gases dissolved in water. The method is based on the evaporation in a high vacuum of a small quantity of water (1 c.c. to 2 c.c.), absorption of tho water vapour by phosphorus pentoxide, and measurement of the pressure produced by the evolved gas. The results are higher than the figures usually accepted.—A. Colani: Study of the systems uranyl sulphate, alkaline sulphate, water, at 25° C.-Félix Taboury: The basic carbonate of beryllium. The decomposition of the ammonium beryllium carbonate does not give the substance indicated by Debray, but a more basic carbonate still containing ammonia. Even after prolonged washing with water charged with carbon dioxide, it is extremely difficult to remove the whole of the ammonia.—Max and Michel Polonovski: A scopinium derivative: reduction to ψ-scopine and degradation to m-oxybenzaldehyde.—Emile Andre and Milé. M. Th. Francois: Contribution to the study of the marine animal oils. Researches on the imsaturated fatty alcohols of spermaceti oil.—Mme. Ramart, Mile. Laclotre, and M. Anagnostopoulos: The action of the organo-magnesium compounds on the a-trisubstituted primary amides. Whilst mono-and di-substituted acetamides give ketones when condensed with organo-magnesium compoxmds, the trisubstituted acetamides yield nitriles.-Raymond Charonnat: The solubility of l-phenyl-2 . 3-dimethyl-4 - dimethylamino - 5 - pyrazolone in water. —Branco Dimitrievitch: The conditions of deposit of the axinite of Mont Avala (Serbia).—Ch. Mauguin: The study of muscovite mica by means of the X-rays.—P. Corbin and N. Oulianoff: The difference and the resemblance of the crystalline schists of the two slopes of the Chamonix valley (massifs of Mont Blanc and Aiguilles Rouges).—Jean G. Popesco: A variation of terrestrial magnetism.—A. Lebediantzef: The modifications of the nitrogenous substances in earth dried in the open air and left fallow.—A. Mordvilko: Anolocyclia in the Pemphigus of Pis-tachia.—F. Henrijean: New researches on the heart and the electrocardiogram.—Philippe Fabre: Relation between the linear constant and the chronaxy.—Ch. Champy and Th. Keller: Uterine and mammary development by injection of ovarian hormone.—J. Houget, Andre Mayer, and L. Plantefol: A particular form of biological oxidation.—L. Margaillan: Remarks on the oil of grape pips.—R. Fosse and Mile. V. Bossuyt: The estimation of allantoic acid as xanthylurea. Application to the analyses of the leaves of Acer pseudoplatanus.
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Societies and Academies. Nature 120, 350–351 (1927). https://doi.org/10.1038/120350b0
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DOI: https://doi.org/10.1038/120350b0