One of those boys, who loved to play with his companions, observed that,
by tying a string from the handle of the valve which opened this
communication, to another part of the machine, the valve would open and
shut without his assistance, and leave him at liberty to divert himself
with his play-fellows. One of the greatest improvement that has been
made upon this machine, since it was first invented, was in this manner
the discovery of a boy who wanted to save his own labour.
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