Page:Popular Science Monthly Volume 18.djvu/446

432 forms of both vegetable and animal life.

experiment of irrigating the lands at Genevilliers with water from the sewers of Paris appears to be working successfully. In answer to protests which have been made against applying a similar irrigation to the forests of St. Germain, the engineers say that the apprehensions that have been expressed on the subject are exaggerated. Many buildings have been put up at Genevilliers since the sewer-waters were taken there, but the inhabitants have never been sick. Moreover, since the prevailing winds are from the west, places lying east of the irrigated district should be the ones most troubled with the infection if there were any; but no complaint has come from Clichy, which is thus situated, while the barren tracts on which it looked have been converted into a fertile plain.

French journals tell of some perfectly fresh meat that became phosphorescent. Some cutlets of raw pork shone so brightly in the kitchen that it was possible by the aid of the light to tell the time by the watch. The butcher from whose shop they came said that all the meat of which they were a part of the stock became phosphorescent within a short time after having been put into his cellar. The phosphorescent meat did not otherwise differ in aspect or odor from common meat; it had not been exposed to a temperature of more than 50°, and entire freshness seemed to be a condition of phosphorescence, so that when the meat began to smell it ceased to be bright. The phosphorescence generally disappeared on the sixth or seventh day.

has communicated to the French Academy of Sciences notes of observations which he has made at the Imperial Observatory, Rio Janeiro, on stars unfavorably situated for observation from the Northern Hemisphere. Some of these stars appear to possess a slow but well-defined orbital motion, amounting in some instances to about six degrees retrograde in forty-three years. They have been observed heretofore only by Sir John Herschel at the Cape of Good Hope, and by Captain Jacob at Poonah, India, and it is from a comparison with their observations that he has deduced the fact of motion.

Royal Society has this year awarded the Copley Medal to Professor J. J. Sylvester, at present occupying the chair of Mathematics in Johns Hopkins University.

has a plan for the civilization of Africa by telegraph. Stations for entertainment and for scientific purposes are to be established at points between the coasts and the interior. Thus a party has already arrived in the Oussagura to establish a station to be connected with Zanzibar, and another party has been commissioned to establish a station on the Ogove River to be connected with the French colony at the Gaboon. The stations are to be connected by telegraphic wires, the planting of which will be preliminary to the building of railways, so that these wires, says M. de Lesseps, will become for Africa, as they were across our Western Plains and are for Australia and for the Russians in Central Asia, real conductors of civilization.

writes in the November number of the "American Journal of Science" that, "during the night of September 30, 1880, I succeeded in photographing the bright part of the nebula in Orion in the vicinity of the trapezium. The photographs show the mottled appearance of this region distinctly. They were taken by the aid of a triple objective of eleven inches aperture, made by Alvan Clark & Sons, and corrected especially for the photographic rays. The equatorial stand and driving clock I constructed myself. The exposure was for fifty minutes. I intend at an early date to publish a detailed description of the negatives."

has succeeded, by changing the form of the reflectors and the heaters, in considerably increasing the efficiency of the solar engines invented by M. Mouchot. While M. Mouchot has not been able to utilize more than fifty per cent, of the heat of the sun, M. Pifre with his improved apparatus makes eighty per cent, available for use. With a receiver of 9·25 square metres and a clear sky he boils fifty litres of water in less than forty minutes, and obtains an additional pressure of one atmosphere every seven or eight minutes.

is proposed to make use of the hydraulic constructions and machinery at Airolo and Goeschenen for the maintenance of electric lights in the St. Gothard Tunnel.

run by electricity has been devised by Messrs. Siemens and Halske of England. It consists of a rod of steel-headed soft iron which moves through three coils of insulated wire; the middle coil is traversed by a constant current which magnetizes the rod, and the other coils are traversed by alternating currents which attract and repel the rod with rapid movements.

chronicles the death of Dr. Hofrath von Wagner, Professor of Technological Chemistry in the University of Würzburg. He was born at Leipsic in 1823, first taught in Nüremberg, and was the author of a standard work on chemical technology, translated into English by Professor Crookes in 1872.