The life of George Stephenson, railway engineer - Lighthouse ...

72 LIFE OF GE0E6E STEPHENSON. [chap. vm.
Marquis of Worcester was greatly struck by the appearance of
De Cans, and afterwards studied his book, portions of which he
embodied in his " Century of Inventions." The Marquis is
also said to have entertained the idea of moving carriages by
steam power, but never embodied it in any practical form.
Savery, the Cornish miner and engineer, who did so much
to develop the powers of the high-pressure engine, also pro-
posed it as a method of propelling carriages along ordinary
roads. But he took no practical measures with the view of
carrying out his suggestion. The subject was shortly after, in
1759, introduced to the powerful mind of James Watt, by Dr.
Eobinson, then a young man studying at Glasgow College.
" He threw out," says Watt, " the idea of applying the power of
the steam-engine to the moving of wheel-carriages, and to other
purposes ; but the scheme was not matured, and was soon
abandoned, on his going abroad." * Watt, however, afterwards,
in the specification of his patent of 1769, gave a description of
an engine of the kind suggested by his friend Robinson, in
which the expansive force of steam was proposed as the motive
power. It also appears that other inventors were in the field
about the same time ; for in a letter written by Dr. Small to
Mr. Watt, on the 18th of April, 1769, it is stated that "one
Moore, a linendraper of London, had taken out a patent for
moving wheel-carriages by steam ; " t but no steps were taken
to reduce the invention to practice. Watt again, in his patent
of 1784, described a similar engine to that indicated in his first
patent, specifying the mode of applying steam to the moving of
wheel-carriages. The plan proposed by Watt, although a cu-
riosity at the present day, bears the impress of his original mind.
The boiler was to be of wooden staves hooped together with
iron; the iron furnace inside the boiler, and almost entirely
surrounded with water ;
the whole being placed on a carriage,
the wheels of which were to be worked by a piston, the recipro-
catory action being converted into a rotatory one by toothed
wheels and a sun and planet motion. The cylinder was to be
* Narrative of James Watt's Invention, in Robinsoii's Mechanical Pliilosophy,
vol. ii. art. Sieant-Engine.
t The Mechanical Inventions of James Watt, by J. P. Muu-head, M, A.