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288 information concerning the red sunsets and the diffusion of volcanic dust, which had not yet been examined; and he could only say that nothing had yet appeared which was inconsistent with the Krakatoa theory.

of St. Petersburg, has devised a telephone for measuring temperatures at a distance. Suppose two stations, A and B, joined by two wires of iron and silver which are soldered at both ends. If the solderings differ in temperature, a thermo-electric current will circulate through the wires, and may be made to express itself by means of a telephonic apparatus; but if the observer, say at A, raises or reduces the temperature of the soldering at his end, till it is identical with the temperatui'e at the end B, the telephone will cease to speak.

a distinguished French chemist and agronomist, died in September, in the sixty-sixth year of his age. He was Professor of Physics in the College of Sainte-Barbe. In 1850 he made an experimental balloon ascension with M. Bixio, to test the temperature and moisture of the air at different elevations. He founded the "Journal de l'Agriculture," and was commissioned by Arago editor of his works, which were published in seventeen volumes.

a prominent Danish entomologist and editor of the "Naturhistorisk Tidskrift," of Copenhagen, is dead, at the age of sixty-nine years.

engineer, who recently died in England, was for seventeen years paid secretary and for twenty-eight years honorary secretary of the Institution for Civil Engineers. lie was the son of Aaron Slanby, an eminent iron-manufacturer, and was engaged in the construction of the first pair of marine engines with oscillating cylinders and upon the building of the Aaron Manby, the first iron steamship that ever made a sea-voyage.

the eminent French agricultural chemist, has recently died, in the sixty-fifth year of his age. He was a man of immense wealth, and employed it in the service of science. He was the author of investigations on phosphureted hydrogen, the action of the electric spark in chemical combinations, and on numerous questions in agricultural chemistry; and he possessed extensive laboratories at Talmay and in Paris.

F. R. S., an eminent English botanist, died on the 10th of September last, in the eighty-fourth year of his age. He was a son of General Samuel (afterward Sir Samuel) Bentham, and a nephew of Jeremy Bentham, the famous economist. His attention was attracted to botany, while the family were living in France, by the perusal of De Candolle's "Flore Française," and he immediately took to the study of the flowers in the back yard. His studies were afterward of a more diversified character, while botany still led, till 1829, when he gave up the profession of the law for his favorite science. He studied the enormous collections of the East India Company which had been brought home by Wallich from India; worked out the flora of Hong-Kong and Australia, the latter in seven volumes, containing seven thousand species, for the Royal Gardens at Kew; revised the orders of the Labiate, Scrophularinæ, Polygoncæ, etc.; and composed, in association with Hooker, the "Genera Plantarum," a complete general work on the phanerogamic plants, which was completed in the spring of 1883. "He has left no equal," says "Nature," "except Asa Gray."

Professor of Zoölogy, Psychology, and Anthropology in the University of Berne, died on the 8th of August last, aged eighty years. He was a man of great literary activity in the fields of natural history and metaphysics. Among his works in the latter field were "A Universal Natural History," in four volumes, a treatise on the smallest forms of life, an introduction to the natural sciences, a text-book of zoölogy, outlines of ethnology, and books on anthropology and psychology.

The death of Dr. author of two well-known works on the electro-magnetic telegiaph and spectrum analysis, is reported. Dr. Schellen was formerly director of the Cologne Realschule, and, besides the works named above, published an arithmetic, a German version of Padre Secchi's book on the sun, and other works on physical subjects. He was sixty-six years old.

inventor of the metallic barometer and manometer which are largely used, died in Paris on the 29th of September, aged seventy-six years.

an eminent entomologist (particularly in the department of Lepidoptera), has recently died at Meran, Tyrol.

a Polish chemist, died in Warsaw, September 16th. He wrote many scientific books in the Polish language, the most valuable of which were a text-book on chemistry and a treatise on organic chemistry; prepared carbamide synthetically in 1856; and improved the methods for determining the density of vapors.