Abstract
PARIS. Academy of Sciences, August 19.-M. Bassot in the chair.-A. Lacroix: The gem-bearing pegmatites of Madagascar. These pegmatites fall into two groups: potassium pegmatites and sodium and lithium pegmatites. The first contains beryls, and also rare minerals containing titanium, niobium, tantalum, uranium (radio-active), cerium, and yttrium; the latter is characterised by numerous lithium minerals, tourmalines of various colours, beryls, red triphane (lunzite), and also minerals containing boron and fluorine.-Richard Birkeland: The trajectory of an electrified particle in a magnetic field.˜L. Wertenstein: The absorption of radio-active projections and the ionisation which they produce.-S. Ratner: The mobilities of the radio-active atom-ions in gases. A study of the mobilities of the atoms of radium B, projected by radium A, Rutherford's method of the alternating field being employed in the measurements.-Jean Bielecki and Victor Henri: The quantitative study of the absorption of the ultra-violet rays by alcohols, acids, esters, aldehydes, and ketones of the fatty series. The photometry of the spectrograms has been utilised as the basis of a quantitative study of the absorption in the ultra-violet. The absorption increases as the molecule becomes more complex. The acid group (CO-OH) possesses a very great absorptive capacity. Other groups possess specific absorption characteristics.-M. Portevin: The effect of tempering upon the electrical resistance of bronzes and brasses.- Georges Baume and F. Louis Perrot: The atomic weight of chlorine. Gaseous hydrochloric acid was allowed to come in contact with liquid ammonia, and the weight of gas necessary to form neutral ammonium chloride determined. Taking N = 14.009, the results lead to Cl = 35'465, practically identical with the international value 35.460.-E. C. Teodoresco: The presence of a nuclease in Algae.
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Societies and Academies . Nature 89, 677–678 (1912). https://doi.org/10.1038/089677b0
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DOI: https://doi.org/10.1038/089677b0