The governing is now done by means of quick-running
governors, which have power enough in them to raise not merely the
weight of the pendulum ball, which is now small, but a very heavy
weight, and in this way the governing is extremely effective. I
propose to say no more, looking at the magnitude of the whole of my
subject, upon the engine used for manufacturing purposes, but rather
to turn at once to those employed for other objects.
STEAM NAVIGATION.
In 1831, there were a considerable number of paddle steamers running
along some of the rivers in England, and across the Channel to the
Continent. But there were no ocean steamers, properly so-called, and
there were no steamers used for warlike purposes. As in the case of
the wagon boilers, the boilers of the paddle steamers of 1831 were
most unsuited for resisting pressure. They were mere tanks, and there
was as much pressure when there was no steam in the boiler from the
weight of the water on the bottom, as there was at the top of the
boiler from the steam pressure when the steam was up. Under these
circumstances, again, from 31/2 lb. to 5 lb. was all the pressure the
boilers were competent to bear, and as the engines ran at a slow
speed, they developed but a small amount of horse-power in relation to
their size.
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