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THE BRAZILIAN TRANSIT OF VENUS EXPEDITIONS, 1882.—We have received vol. iii. of the “Annaes do Imperial Observatorio do Rio de Janeiro,” containing the reports of the Brazilian expeditions to observe the transit of Venus of December 1882. The volume, which is a handsome quarto of some 750 pages, and is fully illustrated with photographs of the various stations and instruments, contains reports from three stations, the weather at the Imperial Observatory at Rio de Janeiro itself, which should have been a fourth station, having proved cloudy and wet. It had been at first intended to send an expedition to Cuba, but as the French astronomers were to occupy a position there, the little Island of St. Thomas, belonging to Denmark, was chosen instead. St. Thomas paired well with the southern station, Punta Arenas, in Patagonia, for the duration was much shortened at the former place and slightly lengthened at the latter, the sun being high at both stations, and ingress and egress at both taking place nearly symmetrically with regard to the meridian. The entire transit was also seen from the remaining station, Olinda, near Pernambuco, where ingress was somewhat retarded and egress much accelerated. The observations were all made by the method of projection, in order that the disturbing effects of irradiation might be got rid of as far as possible. The St. Thomas expedition which was under the command of Baron de Teffé, possessed three equatorials, and Dr. H. Draper had promised to supply a photo-heliograph, but his lamented death prevented the carrying out of his generous intention. The Olinda expedition, commanded by M. T. de Oliveira Lacaille, had two equat rials; whilst M. Cruls, the chief of the Punta Arenas parly, had but one; the largest telescope in each case being 61 inches in aperture. M. Cruls selected a site for his party within a mile of that occupied by Dr. Auwers with the German expedition; for the Brazilian Parliament having delayed the necessary credit for the expedition to the last moment, the expedition did not arrive at the place until late, and it seemed better to take advantage of the German choice of position rather than lose time by surveying for a fresh site at a distance. The observations at each of these three stations were successful, the second internal contact being observed at all, but the first internal contact was lost at St. Thomas. The method of chords could not, therefore, be employed, but the combination of the second contacts of the two northern stations with both contacts of the southern gave 8″.808 as the resulting parallax. A large part of the volume is. devoted to a report of the voyage of the corvette Parnahyba, by Captain L. Saldanha de Gama, the captain who conveyed the southern observing party to their station, and to a description of the natural history of Tierra del Fuego.