Margraf, Andrew Sigismond

, a celebrated chemist, was born at Berlin, March 3, 1709. His father was apothecary to the court, and assessor of the college of medicine, and under his care his attention was naturally turned to the pursuits of chemistry and pharmacy. To pursue these, his father sent him to study under the celebrated professor Neumann, for five years, and subsequently under professor Spielmann, at Strasburg. In 1733 he went to the university of Halle, where be became a pupil of Hoffmann in the study of medicine, and continued his chemical pursuits under the direction of Juncker, to which last science he ultimately devoted his sole attention. He also studied mineralogy, under Henckel, and the art of assaying under Susmilch. In the following year he visited the Hartz mines, and then returned to Berlin, where his incessant application to chemical labours so materially injured his health, that it was never afterwards vigorous. In 1738 he was received into the society of sciences, and furnished some memoirs for the “Miscellanea Berolinensia;” and when this society was renovated in 1744, as the royal academy of sciences and belles lettres, he was placed in the class of experimental philosophy, of which he was chosen director in 1760. He had also the high gratification of being entrusted with the laboratory of the academy in 1754, in which he almost lived, absorbed in the study or practice of his favourite art. He was, nevertheless, a man of great amenity of temper, and considerable conviviality, when mixing in the society of his friends. He had been for some years liable to spasmodic affections, and in 1774, was attacked with apoplexy, which left a paralysis behind it. He continued, however, to attend the meetings of the academy till the autumn of 1776; after which his mental and bodily powers gradually declined, and he died in August, 1782.

Margraf was held in considerable estimation as a chemist, throughout Europe, and had the honour of being elected a member of several learned bodies. All the writings | which he produced were published in the Memoirs of the Literary Society of Berlin, before and after its renovation; tut they have been collected and published both in German and French. They contain the details of a great number of processes and analyses, described in clear and simple language. Some of the most important of his discoveries relate to phosphorus and its acid; to the reduction of zinc from calamine; to the fixed and volatile alkalies; to manganese, the Boiognian stone, platina, and the acid of sugar. In short, he is entitled to rank among the more accurate experimentalists who contributed to the advance*­ment of the science of chemistry, before the recent luminous improvements which it has gained. ¹