The steam engine familiarly explained and illustrated; with an historical sketch of its invention and progressive improvement; its applications to navigation and railways; with plain maxims for railway speculators. By the Rev. Dionysius Lardner ... With additions and notes by James Renwick ...

204 THE STEAM ENGINE.
This, in fact, constitutes a practical difficulty in the applica
tion of steam engines on railroads; and will, perhaps, for
the present, limit their application to lines connecting places
of great intercourse.
The most striking effect of steam power, applied on a railroad, is the extreme speed of transport which is attained by
it; and it is the more remarkable, as this advantage never
was foreseen before experience proved it. When the Liverpool and Manchester line was projected, the transport of
heavy goods was the object chiefly contemplated; and although an intercourse in passengers was expected, it was not
foreseen that this would be the greatest source of revenue to
the proprietors. The calculations of future projectors will,
therefore, be materially altered, and a great intercourse in
passengers will be regarded as a necessary condition for the
prosperity of such an undertaking.
If this advantage of speed be taken into account, horsepower can scarcely admit of any comparison whatever with
steam-power on a railway. In the experiments which I have
already detailed, it appears that a steam engine is capable of
drawing 90 tons at the rate of about 20 miles an hour, and
that it could transport that weight twice between Liverpool
and Manchester in about 3 hours. Two hundred and seventy
horses working in wagons would be necessary to transport
the same load the same distance in a day. It may be objected, that this was an experiment performed under favourable circumstances, and that assistance was obtained at the
difficult point of the inclined plane. In the ordinary performance, however, of the engines drawing merchandise,
where great speed is not attempted, the rate of motion is not
less than 15 miles an hour. In the trains which draw passengers, the chief difficulty of maintaining a great speed
arises from the stoppages on the road to take up and let
down passengers. There are two classes of carriages at present used: the first class stops but once, at a point halfway
between Liverpool and Manchester, for the space of a few