August Wilhelm. A German Chemist Hofmann, born in Giessen, April 8, 1818. He is the son of an architect, and studied chemistry under Liebig, whose assistant he was at the university of Giessen. In 1845, after having been appointed professor at Bonn, he was at Lie-big's recommendation placed in charge of the newly established royal college of chemistry in London, which was united in 1853 to the royal school of mines; and in 1855 he received the additional appointment of chemist to the mint. His reputation as one of the most successful teachers of chemistry of the present day brought him many offers from German governments, and in 1865 he succeeded Mitscherlich in the university of Berlin. Faraday's discovery of benzole among the oily products found in compressed oil-gas holders early attracted Hofmann's attention, and his important researches resulted in 1845 in his discovering the presence of the same substance in coal-tar oil. He indicated by formulas the successive changes in the transformation of benzole into nitro-benzole, and of the latter into aniline; and it is to him that science is indebted for most of the discoveries which have been made in these colors.

The dye known as fuchsine, azaleine, mauve, solferino, magenta, etc, he showed to be a combination of a base, which he named rosaniline, with an acid, usually acetic or hydrochloric. He has recently investigated the conversion of aniline into tolui-dine, and is now (1874) investigating processes for the production of homologues of amines of other classes, and of some of the bases occurring in the organization of plants. He has conducted, with Dr. Bence Jones, the later editions of Fowne's "Manual of Chemistry," and contributed many disquisitions on organic chemistry and other subjects to scientific publications in England and Germany. A royal medal was awarded to him in 1854 for his memoirs on the molecular constitution of the organic bases, and he afterward became president of the chemical society. He wrote the report on the chemical department of the great London exhibition of 1862, and that on the tar dyes in the Paris international exhibition of 1867. His other important works relate to hygiene and to chemical technology, and include Einleitung in die moderne Chemie (1865; 5th ed., Brunswick, 1871), and essays commemorative of Thomas Graham and of Gustav Magnus in the Berichte der deutschen chemischen Gesellschaft (Berlin, 1869-'70).