(315.) 
Philosophi- 
cal spirit 
infused in- 
to practical 
mechanics 
by Watt. 
Estimate 
of Watt’s 
genius. 
(316.) 
866 
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. 
Such combinations of theory and practice have now 
become far from rare. They have followed the march 
of physical learning, they have borrowed from it, 
and they have contributed to it. But it was Watt 
who chiefly gave the happy example. Himself by 
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 generallyregard with 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 
present by philosophy to the arts.’’! Professor Ro- 
bison, who knew Mr Watt intimately, was even more 
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.? 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, 
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- 
MATHEMATICAL AND PHYSICAL SCIENCE. 
(Diss. VI. 
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 Encyclopedia where they 
are explained at full length. 
No doubt we cannot in strictness call Watt the 
inventor of the steam-engine, ‘he grand principle 
the steam< 
of 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 Wart was born at Greenock in 1736, and, 
owing to feeble health, seems to have enjoyed little 
advantage from regular tuition of any kind; which 
was, however, to a great extent made up for by 
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. 
® 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- 
(318.) 
James 
Watt’s 
ly his- 
tne 
