might almost call
them wonders--are now so numerous, that to bring any particular one in a
single form before this meeting is a matter of no easy nature. To-night,
however, I have ventured to single out, and have the pleasure of
bringing before you, the steam-engine, as the prime mover at present of
our workshops and manufactories, as also the grand motive power of our
railways, now so different from the time when the great Stephenson was
said to be mad, because he thought it possible to drive a train at
fifteen miles an hour. For the first serviceable use of this grand
machine we are indebted to the great James Watt. He it was who first
wrought it so as to be under the useful and entire control of man, from
what it was in the time of Hero of Alexandria, about 120 years before
Christ. Our engineers have, since Watt's time, improved upon it year by
year, till at the present day, instead of having to go in a mail-coach
from London to Edinburgh, which formerly took fifty hours, we now go in
the express train in ten, a distance of 420 miles. If beyond this ten
hours, we grumble, and ask guards, porters, &c., at the various
stations, "What has made the train so late to-day?" forgetting that just
before the railways were first opened, the great Stephenson was urged
not to say too much as to the supposed power of the locomotive, in case
the cause of railways might be damaged. This was only some forty years
ago, and it shows us how times are changed, for in the present day we
consider thirty miles an hour anything but a fast train.
The history of the steam-engine is a subject on which so much has been
written in books and magazines now before the public, that what I am
about to offer, though pretending nothing new, yet I hope may be looked
upon as containing something useful as well as instructive, both to the
practical and the amateur mechanic. I shall therefore, in as small a
compass as possible, trace the steam-engine from its first and early
stages up to its present perfect state as our grand motive power. The
first mention made of the vapour of water, as formed by the action of
heat upon it, is found to be as far back as 120 B.C., when one Hero of
Alexandria employed this vapour for the purpose of driving a machine. It
is a well-known fact that when water is brought up to a certain degree
of heat, called the boiling-point, that it sends forth a vapour, the
elastic properties of which, when in an open vessel, are not
perce
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