Abstract
PARIS.
Academy of Sciences, June i8.M. A. dArsonval in the chair.J. Boussinesq: The limiting equilibrium of a sandy mass under given conditions.C. Guichard: Surfaces such that the La- place equation of the network formed by the lines of curvature is integrable. A. Righi: The ionisation of the X-rays in a magnetic field. Earlier work by the author on the influence exerted by the magnetic field on the phenomena of discharge pointed to the existence of a new action of the field on gases tending to increase their ionisation. This effect, to which the name magneto-ionisation is giv§n, may be explained on the assumption that the electromagnetic force acting upon a satellite electron in the atom causes a variation in the energy necessary to separate the electron from the atom. In the present paper a direct experimental proof of this effect is given.R. Bourgeois was elected a member of the section of geography and navigation in succession to the late M. Hatt, and E. Solvay a correspondant for the section of chemistry in the place of the late Sir Henry Roscoe.G. D. Birkhoff: A generalisation of Taylors series.H. Duport: The law of universal attraction.Ed. Chauvenet: The zirconyl sulphates. The six combinations of zirconia and sulphuric acid described in a previous paper are considered from the points of view of modes of formation and probable composition. All are represented as zirconyl salts containing the group ZrO.J. Bougault: The action of iodine on alkalies. A study of the oxidising powers of iodine in presence of caustic soda, sodium carbonate, and sodium bicarbonate.M. Guerbet: The condensation, under the action of potash, of cyclohexanol with isopropyl alcohol. The synthesis of cyclohexylisopropyl alcohol. M. Sauger: The time of fall of a stone to the centre of the earth. The problem is considered, taking into account the variation of the density of the globe with the depth. The time found is im. 155.; on the assumption of a density equal to the mean density the time found is 79s. greater.L. Daniel: The preservation of our oaks. The spread of the fungus causing the Blanc du Ch©ne is shown to be connected with the method of lopping the trees. The usual practice is a drastic lopping every seven years. This destroys the normal moisture equilibrium of the tree; the absorptive apparatus remains intact, but the reduction in the leaf surface causes the retention of an excess of moisture in the tissues, a condition favourable to the spread of the fungus. It has been proved that trees just lopped are more easily attacked than those lopped the preceding year; the latter are more easily attacked than those trees lopped several years earlier. A modified system of lopping is proposed, but it is pointed out that State acon will probably be necessary, since the interests of tbe farmers and owners are opposed, and it is not likely that the cultivators will willingly change their present system of working.Mme. Marie Phisalix: The parotid poison gland of the Colubridal.W. Kopaczewski: Researches on the serum of Muraena helena. The serum of this species is very toxic. A dose of 005 c.c. is fatal to a guinea-pig, an amount corresponding to 4.19 mgr. of dry substance. 04 c.c. of serum killed a rabbit in four minutes, and i c.c. killed a dog (5 kilograms) in seventy minutes.A. Krempf: A new endoglobular hematozoa in man (Haemogregarina hominis). The organism was isolated from the hypertrophied spleen of a Chinese from the neighbourhood of Tientsin. Only one case is described, but it would appear that the disease caused by this organism is common in some parts of China.
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Societies and Academies . Nature 99, 439–440 (1917). https://doi.org/10.1038/099439a0
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DOI: https://doi.org/10.1038/099439a0