ROSE  , the name of a distinguished

family of German chemists . VALENTINE RosE the elder was born on the 16th of August 1736 at Neu-Ruppin, and died on the 28th of April 1771 at Berlin, where he was an apothecary and for a short time before his death assessor of the Ober Collegium Medicurn . He was the discoverer of Rose's fusible metal " (see FUSIBLE METAL) . His son, VALENTINE RosE the younger, born on the 31st of October 1762 at Berlin, was also an apothecary in that city and assessor of the Ober Collegium Medicum from 1797 . It was he who in 1800 proved that sulphuric ether contains no sulphur . He died in Berlin on the loth of August 1807, leaving four sons, one of whom, Heinrich, was a distinguished chemist, and another, Gustav, a crystallographer and mineralogist . HEINRICH ROSE, born at Berlin on the 6th of August 1795, began to learn pharmacy in Danzig, where, during the siege of 1807, he nearly lost his life from typhus . Like his brother he served in the campaign of 1815 . During the summer of the following year he studied at Berlin under M . H . Klaproth, a devoted friend of the family, and in the autumn entered a pharmacy at Iitau . In 1819 he went to Stockholm, where he spent a year and a half with J .

J .

Berzelius, and in 1821 he graduated at Kiel . Returning to Berlin he became a Privatdozent in the university in 1822, extraordinary professor of chemistry in 1823 and ordinary professor in 1835, and there he died on the 27th of January 1864 . He devoted himself especially to inorganic chemistry and the development of analytical methods, and the results of his work are summed up in the successive issues of his classical work, Ausfiihrliches Handbuch der analytischen Chemie, of which he published the first edition at Berlin in 1829, and the sixth, practically a new work in French, at Paris in 1861 . He was the discoverer of antimony pentachloride, and mention may also be made of his researches on the influence of the mass-action of water in many reactions, carried out before the investigations of Guldberg and Waage in 1867 . GUSTAV RosE, born at Berlin on the 18th of March 1798, began his career as a mining engineer, but soon turned his attention to theoretical studies . A pupil of Berzelius like his brother, he graduated in 182o at Berlin University where he became successively Privatdozent (1823), extraordinary professor of mineralogy (1826) and ordinary professor (1839) . In 1856 he succeeded to the directorship of the Royal Mineralogical Museum at Berlin, and he helped to found the German Geological Society, of which he was president from 1863 until the end of his life . He made many journeys in different parts of Europe for the sake of mineralogical study, and in 1829 with A. von Humboldt and C . G . Ehrenberg (1795-1876), professor of medicine at Berlin, took part in an expedition to the Ural and Altai mountains and the Caspian Sea, which yielded information of primary importance concerning the mineralogy of the Russian Empire . His work covered every branch of mineralogy, including crystallography and the artificial formation of minerals .

The

science of petrography, according to Gerhard vom Rath, originated with him . He was the first in his own country to use the reflecting goniometer for the measurement of the angles of crystals, and to teach the method of studying rocks by means of microscopic sections . He also devoted special attention to meteorites and to the problem presented by the different structure of the stony matter in them and in the crust of the earth, and just before his death, which took place at Berlin on the 15th of July 1873, he was engaged in investigating the formation of the diamond . In addition to many scientific memoirs he published Elemente der Krystallographie (183o) ; Mineralogischgeognostische Reise nach dem Ural, dem Altai and dem Kaspische Meere (1837) vol. i.; (1842) vol. ii.; Das Krystallo-chemische Mineral-system (1852); and Beschreibung and Eintheilungder Meteoriten (1863) .