PARIS. Academy of Sciences, September 18. —M. Armand Gamier in the chair.—Ch. Lallemand: The deformations resulting from the mode of construction of the international map of the world on the scale of one millionth. The author establishes simplified formula for the construction of the map, having regard to the accuracy possible with the scale chosen. It is shown that the linear and angular errors, due to the method employed, would be much less than those due to the hygrometric deformations of the paper on which the map is printed.—Edm. van Aubel: Hall's phenomenon and the transversal thermo-magnetic effect in graphite. Details of measurement of the thermoelectric power of a graphite-copper thermocouple. This was found to be +17.8 microvolts per degree between 21.0° C. and 57.6° C., and 18.1 microvolts per degree between 20.9° C. and 98.55° C.—Georges Baume and Albert F. O. Germann: Fusibility curves of gaseous mixtures: the Oxonian systems formed by acetylene, ethylene, nitric oxide, and methyl oxide. Diagrams are given showing the fusibility curves of the systems (methyl oxide-acetylene), (methyl oxide-ethylene), and (methyl oxide-nitric oxide). Each of these curves shows a clearly marked angular point corresponding to the molecular proportions ((CH3)20+C2H2), ((CH3)20+C2H4), and ((CH3)2O + 2NO). —J. Bougault and C. Charaux: Lactarinic acid, a keto-stearic acid extracted from some fungi of the genus Lactarius. This acid is present in the free state in L. theiogalus, L. plumbeus, L. pyrogalus, and L. uvidus, and can be extracted by boiling alcohol. The properties of the acid are described; it is shown to be a ketostearic acid of the composition C18H34O3—P. Gaubert: The indices of refraction of some crystalline liquids. Measurements of the refractive indices of propionate, benzoate, acetate, and caproate of cholesterol are given.—E. Kayser and H. Delaval: Contribution to the study of ropy bread.—Charles Nicolle, A. Conor, and E. Conseil: The nature and the seat of the pathogenic agent in exanthematic typhus. Experiments are adduced in support of the hypothesis that the virus is localised in the leucocytes. The blood was separated by centrifugation; the white corpuscles proved on inoculation to be the most virulent; the plasma is less active, and appears to owe its poisonous action to the leucocytic debris difficult of removal; the wasted red corpuscles are inactive. The blood serum was proved to be inoffensive to man, and the cephalorachidian fluid, devoid of cells, proved to be also inactive.