Academy of Sciences, October 27.—M. Hermite in the chair.—Observations of the planet Venus at Nice Observatory, by M. Perrotin. (See Our Astronomical Column.)—On the reduction to the canonical form of differential equations for the variation of arbitrary constants in the theory of movements of rotation, by M. O. Callandreau.—The neutral meridian of Jerusalem-Nyanza, proposed by Italy to fix the universal hour, determined by its horary distance from 120 observatories, by M. Tondini. A list is given of the time-intervals of sixteen important observatories from the Jerusalem meridian, which cuts the equator about 75 kilometres east of Lake Nyanza. This list is part of a larger one giving the latitudes and time-intervals of 120 observatories from the same meridian. —On the developments in series of the integrals of certain differential equations, by M. R. Liouville.—Periodic visibility of interference phenomena when the light source is limited, by M. Ch. Fabry.—Thermo-electric researches, by MM. Chassagny and Abraham. It is well known that if thermo-electric couples be formed from three metals, A, B, and C, the electromotive forces obtained at a given temperature in each case may be expressed by the following equation:— E(AC)=E(AB) + E(BC).