I30 GREAT MEN OF SCIENCE 



Edinburgh. In the year 1756, he became Professor of 

 Chemistry at Glasgow as the resuh of his work on the 

 alkaHs, as successor to his own teacher; ten years later he 

 succeeded him again in Edinburgh, and died there at the age 

 of seventy-one. In his early years he practised with great 

 success as a medical man. The fact that he published little 

 during his life, but communicated all his knowledge by word 

 of mouth, particularly in his lectures, which were very much 

 liked and which he left behind him in full manuscript form,^ 

 is in accord with everything we know concerning his very 

 high character and the never changing calm of his mind. He 

 was very tall and thin, with a pale complexion; his large 

 eyes, we are told, were clear, dark, and deep. 



James Watt, famous for his development of the steam 

 engine, who produced the low pressure engine by inventing 

 the separate condenser and designing all the other details, 

 and also carried out this engine on a large scale, was born at 

 Greenock, in the west of Scotland. He was a very lively but 

 rather sickly child, who soon began to read greatly, but also 

 had a strong taste for mechanical occupations By reason 

 of the poverty of his family, he was apprenticed at the age of 

 eighteen to a mechanic in Glasgow, and then sent to London. 

 Three years later he became mechanic at the University in 

 Glasgow. His workshop was much visited by the professors, 

 who took pleasure in his versatility, his skill and his simple 

 and open nature. Black also made friends with the mechanic 

 eight years his junior, who was so allied to him in nature, 

 and an intimacy between the two remained, which was 

 particularly shown in the support which later was given by 

 Black to Watt when in difficulties. 



In the year 1759, Watt learned for the first time of the 

 steam pumping engine, called the 'fire machine,' which was 



^ They were collected and published, with a preface by John Robison, 

 in 1803. See also Black's Life and Letters, by Sir William Ramsay, 1918. 



