BITS. See BRIDLE.
BLAC K, 1)n JOSEPH, was born in France, on the banks of the Garonne, in the year 1728. His father, Mr John Black, was a native of Belfast in Ireland, hut of a Scots family, which had been for some time settled in that country. Mr Black resided for the most part at Bordeaux, where he carried on the wine trade. He married a daughter of Mr Robert Gordon, of the family of Hillhead in Aberdeenshire, who was also engaged in the same trade at Bordeaux. • In the year 1710, when young Black had reached the age of 12, he was sent home to Belfast, that he might have the education of a British subject. After the ordinary instruction of a grammar school, he was sent in 1746 to continue his education in the university of Glasgow. Being required byhis father to make choice of a profession, he pitched upon medicine, as most suited to his peculiar views, and congenial to his studies.
Fortunately at this period Dr Cullen began his great career, and had pitched upon philosophical che mistry as a field hitherto untraversed and unopened. It had been treated as a curious art, susceptible of improvement from rational inquiry and discussion. But Dr Cullen saw in it a great department of the science of nature, founded on principles as immutable as those of mechanical philosophy. He undertook the task of developing and arranging these principles, and he promised to himself great reputation from the accomplishment of it. His pupils, in consequence of his new views, became zealous chemists, and young Black in particular devoted himself to the study. This was soon observed by Dr Cullen, who possessed the happy talent of exciting and encouraging his pu pils in an eminent degree. Mr Black became his in timate friend, his assistant in all his investigations, and his experiments were frequently quoted in the lecture as sufficient proofs of the positions of the professor.
In 1750 he went to Edinburgh to finish his medi cal studies, and he lived in the house of Mr 3ames Russel, professor of natural philosophy, his cousin german. About this time the professors had adopted different opinions respecting the action of lithontrip tic medicines. Those which produced the most power ful effects in alleviating the excruciating pains of the stone, were of a very corrosive nature. It was there fore an object of great importance, to discover, if pos sible, some equally efficacious medicine, which shall not possess corrosive properties ; or if that cannot be done, at least to diminish or destroy the corrosiveness of the medicines in use, without impairing their me •clical virtues. It was these views that led Mr Black
to investigate the nature and properties of magnesia, and which induced him to contrive and execute the experiments which laid open the nature of causticity itself, and showed upon what it depends. This im portant subject he destined for his inaugural disserta tion ; and he appears to have delayed taking out his medical degree till he had brought. his investigation to a state of maturity.
Fortunately when be took his doctor's degree, and published his important discovery of-the cause of the difference between lin:Intone and quicklime, mild and caustic alkalies, a vacancy occurred in the chemical chair in Glasgow. His friend and master Dr Cullen having been removed to Edinburgh, there could he no hesitation in bestowing the vacant chemical chair upon the author of a discovery, which was destined to produce a complete revolution in chemical science. Dr Black was accordingly appointed professor of ana tomy and lecturer on chemistry in the university of Glasgow in the year 1756. Not considering himself as well qualified for the professorship of anatomy, he exchanged tasks with the professor of medicine, with the concurrence of the university.
While in Glasgow, therefore, his lectures on the institutes of medicine constituted his chief task. They gave general satisfaction, by their clearness and sim plicity, and by the cautious moderation of Lis gene ral principles. He became likewise a favourite prac titioner in that rich and active city, arid his business extended every year during his whole stay in Glas gow. Thus the greatest part of his time was taken up in the practice of medicine, or in increasing his stock of medical knowledge with a view to the im provement of his lectures. Chemistry, as far at least as he was concerned, constituted but a secondary object. This may serve, in some measure at least, to explain the seemingly unaccountable fact, that he never attempted to enter that vast and tempt ing field of investigation which he had laid open.