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JOSEPH BLACK. 



1728-1799. 



" No professor took a more lively interest in the progress of an emulous student 

 than Dr. Cullen. It was his delight to encourage and assist their efforts, and therefore 

 he was not long in attaching Mr. Black to himself, in his most intimate co-operation." 

 (Professor J. Robinson's Preface to Black's Lecture on Elements of Cliemistry.) 



CULLEN was attracted by the teaching of Stahl, and for a time 

 followed chemistry with ardour before he devoted himself 

 to medicine. He was the teacher of Joseph Black, and Black 

 became his successor — Black, " who first struck out a new and brilliant 

 path, which was afterwards fully laid open and traversed with such 

 eclat by British philosophers who followed his career." 



Black's father — a wine merchant — was of Scottish descent, and 

 he himself was born at Bordeaux, on the banks of the Garonne, in 

 France, in 1728. In 1746 Black entered Glasgow University, and 

 became assistant to Cullen. Black in 1750 went to Edinburgh to 

 pursue his medical studies and there carried out investigations on 

 limestone and quick-lime. He took his degree of M.D. in 1754, 

 presenting, as his thesis, Dissertatio tie Humore acido a Cibo orto et 

 de Magnesia. The faculty at that time were discussing the action of 

 lime-water as a lithontriptic. Limestone he showed to be a mixture 

 of lime and an aereal substance to which he gave the name "fixed air" 

 i.e., carbonic acid. When Cullen became Professor in Edinburgh, 

 Black succeeded him in Glasgow in 1759. 



'6' 



" His first appointment in Glasgow was to the Professorship of Anatomy, and 

 the Lectureship on Chemistry. He did not consider himself as so well qualified to be 



useful in the former branch of medical study He made arrangements with 



the Professor of Medicine, and, with the concurrence of the University, the Professors 

 exchanged their tasks. His lectures, therefore, on the Institutes of Medicine were his 

 chief task." (J. Robinson, Preface, xxix.) 



It was in Glasgow that he made his famous investigations on 

 heat and latent heat. In 1766 Cullen became Professor of Medicine, 

 and Black succeeded him in the Chair of Chemistry. He died in 

 1799, peacefully, sitting at his frugal table, where he was found 

 by his servant "with his cup — which contained milk diluted with water 

 — on his knees, which were joined together, and kept it steady with 

 his hand in the manner of a person perfectly at ease." His discoveries 

 were all made before he reached the age of thirty-four. Black 

 in Glasgow had as a pupil James Watt — who may well be called — 



" Dr. Black's most illustrious pupil ! for surely nothing in modern times has made 

 such an addition to the power of man as Watt did by his improvements on the steam 

 engine, which he professes to owe to the instructions and information received from 

 Dr. Black." 

 B 



