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 ...

152 THE STEAM ENGINE.
Tydvil, in South Wales. It was in principle the same as
that already described. The cylinder, however, was in a
horizontal position, the piston-rod working in the direction
of the line of road: the extremity of the piston-rod, by
means of a connecting rod, worked cranks placed on the
axletree, on which were fixed two cogged wheels: these
worked in others, by which their motion was communicated
finally to cogged wheels fixed on the axle of the hind wheels
of the carriage, by which this axle was kept in a state of
revolution. The hind wheels being fixed on the axletree,
and turning with it, were caused likewise to revolve; and so
long as the weight of the carriage did not exceed that which
the friction of the road was capable of propelling, the carriage would thus be moved forward. On this axle was
placed a fly wheel to continue the rotatory motion at the
termination of each stroke. The fore wheels are described
as being capable of turning like the fore wheels of a carriage,
so as to guide the vehicle. The projectors appear to have
contemplated, in the first instance, the use of this carriage
on turnpike roads; but that notion seems to have been abandoned, and its use was only adopted on the railroad before
mentioned. On the occasion of its first trial, it drew after
it as many carriages as contained 10 tons of iron a distance
of nine miles; which stage it performed without any fresh
supply of water, and travelled at the rate of five miles an
hour.
(84.) Capital and skill have of late years been directed
with extraordinary energy to the improvement of inland
transport; and this important instrument of national wealth
and civilization has received a proportionate impulse. Effects
are now witnessed, which, had they been narrated a few
years since, could only have been admitted into the pages
of fiction, or volumes of romance. Who could have credited the possibility of a ponderous engine of iron, loaded
with several hundred passengers, in a train of carriages
of corresponding magnitude, and a large quantity of water