Abstract
Paris. Academy of Sciences, August 7.—M. G. Bigourdan in the chair.—B. Baillaud: A new transit instrument recently installed at the Paris Observatory.—S. Winogradsky: The supposed transformation of the nitrifying ferment into a saprophytic species. A criticism of the views of M. Beijerinck on the nitrifying organism.—M. Abramesco: Developments in series with two complex variables following the inverse of given polynomials.—D. Yovanovitch: The chemical properties of mesothorium-2. Radioactive barium chloride is precipitated by hydrochloric acid: the precipitate contains mesothorium-i, thorium-X, and radium. The mesothorium-2 is precipitated as hydrate, and freed from thorium B and C by treatment with sulphuretted hydrogen after adding a little lead and bismuth. Its chemical properties resemble those of lanthanum.—J. Orcel: The chemical composition of aerinite.—J. Barthoux: Minerals of the Oudjda region (Morocco). The following minerals have been found in a lead mine near Oudjda: galena, vanadinite, pyromorphite, wulfenite, cerussite, dolomite, calcite, and aragonite: details of the crystal forms are given.—Aime Azam: The constitution and origin of the sediment of the plain of Caen called rougeauts and fauvets.—J. Voicu: The influence of humus on the sensibility of Azotobacter Chroococcum towards boron. In a culture medium without humus the effect of boron on the nitrogen assimilated is insignificant, but if humus is added to the culture the toxic action of boron is marked, and the amount of nitrogen fixed is reduced.—René Maire and E. Chemin: A new marine pyrenomycete.—F. Granel: The structure and development of the pseudo-brarichia of the teleosteans.—Paul Portier and Marcel Duval: The variation of the osmotic pressure of the blood of the eel as a function of modifications of the salinity of the external medium. The osmotic pressure of the blood serum of the eel living in fresh water is much higher than in the carp; when the salt in the water is changed from o to 39 parts per 1000, with corresponding change in the freezing-point from — o°.02 to — 2°.22, the freezing-point of the serum changes only from — o°.63 to o°.83, and the fish is not prejudicially affected. In salt solutions of higher concentration than sea water the eel dies. —Mile. T. Duboc: The action of tribromoxylenol on tubercle bacilli.—A. Trillat: The influence of humidity and vesicular state on the diffusion in air of drops containing micro-organisms. From 98 per cent, to 99.5 per cent, of the liquid dust produced by an ordinary pulveriser fall within a few metres of the point of origin. But of the remainder, some drops are so small that they remain in suspension, especially if the air is nearly saturated with moisture, and may travel considerable distances. That microorganisms may be carried in this way has been proved by exposure of Petri dishes, and also by experiments with animals (mice).
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Societies and Academies. Nature 110, 332 (1922). https://doi.org/10.1038/110332a0
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DOI: https://doi.org/10.1038/110332a0