Abstract
PARIS. Academy of Sciences, October 17.—M. Mascart in the chair.—On the four first numbers of the photographic catalogue of the heavens published by the Observatory of Toulouse: M. Lœwy. The parts now published contain the rectilinear coordinates of 32,275 stars, obtained from 186 negatives. The introduction to vol. ii., by M. Baillaud, also gives a complete account of the method of reduction followed at Toulouse, as well as of the special methods used in the measurements of the coordinates and for the calculation of the constants. An account is also given of the method adopted for measuring the relative magnitudes of the stars and of an experimental study of the photographic objective employed. Statistical studies made at the Observatories of Oxford, Toulouse, and Potsdam have shown that the mean distribution of the star images in the negatives of the catalogue is not uniform, and prove that the focal surfaces of the six objectives studied (Algeria, Oxford, Paris, Potsdam, San Fernando, and Toulouse) have an appreciable curvature—The study of the third group of air bands with a strong dispersion: H. Deslandres and A. Kannapell. A detailed description is given of the study of the third group of air bands occupying the more refrangible half of the ultra-violet region (A 3000 to A 2000). The general result confirms the conclusions arrived at in 1885, each band under strong dispersion being always formed of eight series of rays in arithmetical progression. A drawing is given for the band A 2370, in which this structure is clearly shown.—On a new system of micrometers: G. Millochau. The wire micrometer, which is attended with certain inconveniences, is replaced by an instrument based on the principle of the heliometer. Two identical plates of glass with parallel faces are placed in a plane perpendicular to the optical axis of the telescope employed, between the objective and the eye-piece. The plates turn round a common axis and give rise to a double image of the star, the distance between the two images being practically independent of small displacements of the telescope.—Observations of the sun made at the Observatory of Lyons with the 16 cm. Brunner equatorial during the second quarter of 1904: J. Guillaume. The results are summarised in three tables giving the number of spots, their distribution in latitude, and the distribution of the faculae in latitude.— The elements of molecular vibrations in relation with the sense of propagation of sound waves: L. Bard. In view of the impossibility of explaining the orientation of sound by the ear by the usual theories, the author propounds two hypotheses to explain this.—Researches on the boiling points of mixtures of volatile liquids: C. Marie. The boiling point constants of a given pair of volatile liquids and a nonvolatile substance being given, the question is raised as to whether it is possible to calculate, a priori, the value of the boiling point constant corresponding to the mixture. This calculation has been made by Nernst, and an experimental study of this formula has been made by the author with mixtures of water and alcohol and resorcinol. The divergence between the theory and the results of the experiments is considerable, and an examination of the fundamental assumptions used in the formula is made to see if the cause of the divergence can be elucidated. Further experiments are required before the theory can be completely made out.—The action of solutions of organomagnesium compounds on the halogen derivatives of phosphorus, aisenic, and antimony: V. Auger and M. Billy. Phosphorus trichloride reacts violently with solutions of magnesium methyl iodide, giving the chloride of tetramethyl-phosphonium, phosphorus iodide, and magnesium chloride. With chloride of arsenic the chief product of the reaction is trimethylarsine oxide; with antimony trichloride several substances are formed, from which, by treatment with potassium iodide, the iodide of ethylstibine can be isolated. —On n organic persulphate: R. Fossd P. Bertrand. The sulphate of dinaphthopyranol, obtained by treating dinaphthopyranol with dilute sulphuric acid, possesses oxidising properties, setting free iodine from an acidified solution of potassium iodide, and oxidising alcohol to aldehyde. It thus appears to be a true persulphate, analogous in composition with Caro's acid.—The constitution of rosaniline salts and the mechanism of their formation: Jules Schmidlin.—Anthracene tetrahydride and octahydride: Marcel Godchot. These hydrides have been obtained by applying the method of Sabatier and Senderens. The octahydride is the more stable of the two, and is the main product when the hydrogenation is carried out at 200° C. The oxidation products and the reactions with the halogens have been studied.—On the origin of the carbonic acid of the seed during germination: Edouard Urbain. It is established that the carbon dioxide is produced at the expense of the albuminoid materials of the seed.—Study on the successive states of plant material: Eug. Charabot and Alex. Hebert.—Vital periodicity of animals submitted to the oscillations of level in deep sea: Georges Bohn.—The agglutinating cells in the Eolidia: Paul Abric.—Description of some new species of trypanosomes and parasitic Hæmogregarina of marine Teleostea: E. Brumpt and C. Lebailly.—On the auxospores of two pelagic diatoms: J. Pavillard.—The geology of the Ortler region: Pierre Termier.—On macles: G. Friedel.
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Societies and Academies . Nature 70, 643–644 (1904). https://doi.org/10.1038/070643a0
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DOI: https://doi.org/10.1038/070643a0