Abstract
PARIS. cademy of Sciences, August 12.—M. Bouquet de la Grye in the chair—Integral curves of differential equations; George Remoundos.—The accidents arising during the manipulation of compressed oxygen, and on an arrangement permitting of their avoidance: Georges claude. The ordinary forms of regulator for reducing the pressure contain a piece of ebonite, and this is liable to catch fire and even to inflame the steel cylinder. The author describes a simple modification of the regulator by which any local elevation of temperature in the neighbourhood of the ebonite is avoided.—A dynamo designed, for wireless telegraphy P. Villard. This dynamo has been designed so that the voltage curve is analogous to that of a Ruhrnkorff coil, and, in addition, allows the time interval between the successive sparks to be regulated mechanically. The nature pf the voltage curve produced has been studied by means of the oscillograph, curves from which are reproduced in the paper. Experiments have been made with this instrument both in the laboratory and in the field, and for equal motive power the results are much superior to those obtained with a coil. The dynamo is also useful for the production of X-rays.—The maximum of phosphorescence: J. de Kowalski and C. Garnier. A discussion of some recent results on the same subject by L. Bruninghaus.—The cause of the beating of the heart: H. Kronecker. Serum from the blood of a calf was subjected to diffusion in a current of flowing water so that the amount of sodium chloride was reduced to 0.6 per cent. This fluid was used to replace the blood in the cardiac cavities of the frog, toad, and tortoise, and it was found possible to suppress completely the beats of the heart for one hour. Any stimulus applied during this period of arrest caused either a strong pulsation or a group of pulsations. The effects of other solutions are also recorded. The conclusion is drawn from these experiments that the heart does not beat automatical, but requires stimulants of a chemical nature to act on the nervous plexus pf the heart.—The reaction of tuberculin in leprosy (subcutaneous, dermic, and conjunctival inoculations): "Charles. Nicolle.—Observations on the Eocene and Oligocene in Hampshire: Jean Boussac.—The results of observations of the intensity of gravity at the island of Booth-Wandel, Grahamsland, by the Antarctic expedition of Dr. J. Charcot: M. Matha. An account is given of the experimental method used and the accuracy attained. The value of g found, 982.439, is higher than the value calculated from the formula of Defforges, g=978.106 (1—0.005243 sin2 A), by 0.116 cm. This difference is in full accord with the results of Foster in the same regions.—The paroxysms of Stromboli: A. Ricco.
Article PDF
Rights and permissions
About this article
Cite this article
Societies and Academies . Nature 76, 440 (1907). https://doi.org/10.1038/076440a0
Issue Date:
DOI: https://doi.org/10.1038/076440a0