Abstract
PARIS. Academy of Sciences, August 14.—M. Paul Appell in the chair.—C. Richet: The conditions which influence the average monthly deviation of the birth-rate. In countries with a high birth-rate (more than 350 per 10,000) the mean monthly deviation of the birth-rate is more than double that of countries with low birthrate.--E. Esclangon: The sound of gunfire and zones of silence. The detonations arising from the sudden expansion of gas at the mouth of the gun and from the'explosion of the shell, even of the largest calibre, are inaudible at about 30 kilometres, and the author concludes that the sounds heard at distances of 50 to 200 kilometres from the front are due to the waves set up in the air by projectiles moving with initial velocities greater than the velocity of sound.-L. Bouchet: The electric expansion of solid insulators in the sense normal to an electrostatic field. The changes of length were observed by an interferential method for glass, ebonite, and paraffin. Calculations based on Maxwell's equation for the pressures normal to the field' agree well with the experimental figures for paraffin wax, but are not in accord with the results for ebonite and glass.-R. Ledoux-Lebard and A. Dairvlllier: Theoretical and experimental researches on the bases of radiological dosimetry.-Ed. Lesne and M. Phocas: The presence of living and virulent microorganisms at the surface of projectiles enclosed in ocicatrised tissues. Experiments with bullets extracted from healed wounds demonstrate the reality of latent microbism.
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Societies and Academies . Nature 97, 555–556 (1916). https://doi.org/10.1038/097555b0
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DOI: https://doi.org/10.1038/097555b0