William Murdock's
Locomotive, 1784.
This cut
shows a longitudinal section of a miniature locomotive,
made by William Murdock in 1784. It had a single
vertical cylinder _" dia. by 2" stroke,
the slide valve was actuated by a tappet motion,
the beam striking it up and down alternately at
each end of the stroke, the piston rod was connected
to one end of a beam vibrating upon a joint at the
other, as in the class of engines now known as "grasshoppers."
A connecting rod was joined to the beam, close to
its working end, and turned a crank in the axle
of a pair of driving wheels 9_" dia. The cylinder
was half immersed in a small copper boiler, through
which a flue passed obliquely, the heat being supplied
by a spirit lamp beneath. This machine is still
in existence and is the property of Mr. Murdock,
manager of the Sun Foundry, Leeds and grandson of
William Murdock.