68 



MATHEMATICAL AND PHYSICAL SCIENCE. 



[Diss. VI. 



properties of steam as a source of power ; but he was 

 almost the first to study them as a philosopher, and 

 to apply, with exemplary patience and skill, princi- 

 ples sought in the laboratory, to make available the 

 most convenient of all motive forces. This was done 

 by means of a series of contrivances so ingenious 

 so strictly connected by scientific relations as to be 

 a model of experimental research, quite as much as 

 a triumph of mechanical art. 



(315.) Such combinations of theory and practice have now 

 Philosophi- b ccolne far from rare. They have followed the march 

 infused in- ^ physical learning, they have borrowed from it, 

 to practical and they have contributed to it. But it was Watt 

 mechanics ^ho chiefly gave the happy example. Himself by 

 y ' education and habit strictly a mechanic, he had the 

 peculiar merit of apprehending the value of theory, 

 and of acquiring a kind of knowledge then altogether 

 uncommon amongst persons of his profession. He 

 was no doubt a successful speculator, and a shrewd 

 ingenious man besides ; and this, his ostensible cha- 

 racter, constituted possibly in the eyes of many his 

 world- wide celebrity. But such considerations were 

 little likely to influence the opinions of contemporary 

 scientific men well qualified to judge, and least of all 

 of eminent foreigners, who generallyregardwith little 

 partiality the presumed commercial character of their 

 insular neighbours. Dr Black, who was by no means 

 prodigal of praise, termed the steam-engine, as im- 

 proved by Watt, " an invention which is in its pre- 

 sent state the master-piece of human skill," not 

 " the production of a chance observation, but the 

 result of deep thought and reflection, and really a 

 Estimate present by philosophy to the arts.' u Professor Ro- 

 of Watt's bison, who knew Mr Watt intimately, was even more 

 genms. enthusiastic in his appreciation of his genius ; and 

 Sir Humphry Davy, in a speech manifesting a just 

 estimate of his peculiar merits, did not hesitate to 

 place him on a level with Archimedes. 2 But a tes- 

 timony more authoritative and unbiassed than any 

 of these, is the fact that Watt was elected first a 

 corresponding member of the French Institute, and 

 finally one of the eight foreign Associates of the Aca- 

 demy of Sciences. This honour, to which so few can 

 attain, which Newton once owned, and which now 

 graces or lately graced the names of Young, Hum- 

 boldt, Oersted, Brewster, and Robert Brown, is a 

 sure passport to scientific immortality. Here, at 

 least, no utilitarian pride, nor even the laudably pa- 

 triotic emotion of gratitude to one who had proved, 

 in more ways than one, his country's benefactor, can 

 be supposed to have influenced in the remotest de- 

 gree his election. 



(316.) Having said thus much on the position to which 

 Watt's inventions entitle him in the narrative of the 

 history of science, we may refer with brevity to the 

 generally well-known improvements of the steam- 



of 



engine, in which they mainly consist. In Sir John 

 Leslie's Dissertation, a space of but a few lines has 

 been devoted to them, which seems inadequate to 

 their importance. For details, however, we must 

 refer to the articles in the Encyclopaedia where they 

 are explained at full length. 



No doubt we cannot in strictness call Watt the 

 inventor of the steam-engine. The grand principle ., 



. . . -ill tne stean 



or rendering the heat contained in steam available as engine. 

 an economical source of moving power may be traced 

 so far back that we lose the clue altogether in the 

 obscure, or impracticable, or simply puerile shapes 

 in which the idea was contained. Even in the time 

 of Worcester (1663) we must be allowed to doubt 

 whether the history of the steam-engine had out- 

 grown the mythical stage ; Papin, indeed, proposed 

 a piston and cylinder in which the vacuum was pro- 

 duced by steam instead of by the air-pump (as already 

 suggested or practised by Guericke) ; but Savery 

 (1698) was the first who constructed a steam-engine, 

 and applied it to the drainage of mines. His inven- 

 tion included the two capital properties of steam, its 

 power of producing a vacuum by condensation, and 

 its elastic force at high temperatures. A few years 

 later the piston-form was introduced or re-invented 

 by Newcomen and Cawley, as well as the valuable 

 expedient of producing condensation by a squirt of 

 cold water injected into the cylinder ; and in this 

 condition the Atmospheric Engine remained with 

 slight improvement for above half a century, doing 

 the work for which it was invented, the pumping 

 of water out of shafts (the pump being moved by a 

 chain attached to the end of a horizontal oscillating 

 beam), wherever economy of fuel was unimportant. 

 Such was the case at coal pits, but in other mines, 

 usually situated remote from coal, it was of compara- 

 tively little use, on account of the enormous con- 

 sumption of fuel. 



JAMES WATT was born at Greenock in 1736, and, (318.) 

 owing to feeble health, seems to have enjoyed little James 

 advantage from regular tuition of any kind ; which a , ! . 

 was, however, to a great extent made up for by the tory, 

 intelligent spirit with which he acquired knowledge 

 without assistance on a great variety of subjects. At 

 the age of nineteen he proceeded to London, where 

 he learned mathematical-instrument making, but he 

 soon returned to Scotland, intending to pursue that 

 business in Glasgow. Here he met with obstacles, 

 but finally, by the patronage of Dr Adam Smith, Dr 

 Black, and other professors, he was established as 

 instrument-maker to the university within the college 

 buildings. I mention these details because they show 

 that Watt, as early at least as 1757, had been favour- 

 ably noticed by the most celebrated professors then 

 in Glasgow, and had received a special pledge of their 

 good will. ; It is evident that the professors of Che- 



1 Lectures, i., 181. 2 Speech at Freemasons' Hall, preserved in Arago's Eloge of Watt, and in Davy's Works, vol. vii. 



3 It appears from Mr Muirhead's work on The Origin and Progress of the Mechanical Inventions of James Watt (published since 



the greater part of the text of this section was written), that Watt's introduction to the college took place " through the instru- 



