red
hot, the chamber charged with air, and the spray of creosote, injected
by the pump, F, is ignited; the expansion of the gases produced by the
combustion acts upon the bottom of the piston, B, forcing it to the top
of the cylinder, and thus, by intermediate mechanism, causing the crank
shaft to revolve. By the same stroke a charge of air is forced by the
compressor, C, into the receiver through the pipe, R. The cylinder is,
of course, single acting, and on the down stroke of the piston, B--which
falls by its own weight and the momentum of the fly wheel--the exhaust
gases are forced through the regenerator, E, which absorbs most of their
heat; they then pass through the exhaust valve, placed immediately under
the feed valve, M, along the pipe, Q, up through the pipes, T, fitted
into the receiver, V, down the pipes, T, fitted into the saturator, Y,
and out of the funnel fixed to the bottom of Y.

[Illustration: Fig 3.]

[Illustration: Fig. 4.]

The charge of air for supplying the combustion chamber is forced by the
compressor, C, through the pipe, R, _outside_ the tubes, T, in the
chambers, V and Y, along the pipe, P, through the feed valve, M, and the
regenerator, E, into the combustion chamber. In its passage from the
compressor, it first picks up the residual heat of the exhaust gases in
the tubes, T, and finally the heat absorbed by the regenerator, E, thus
entering the combustion chamber in a highly heated state. Having
described generally the passage of the air from the compressor to the
working cylinder, and back again to the funnel, we will now describe the
details. The working cylinder, A, is fitted into the casting which forms
the water casing, K, a space being left between the bottom of the
cylinder and the casing, which is filled with a non-conducting mixture
of asbestos to protect it from the heat of combustion; the bottom of the
piston, B, has a similar protection, and the regenerator has a lining
of the same mixture, to prevent any heat from escaping through the
casting which holds it. The water in the casing, K, and in the piston,
B, is supplied by a small pump, G, which forces the water through the
pipe, P4, into the telescopic pipe, L either into the piston, B, or
through the pipe, P6, into the casing, K--the bottom of the casing
being connected by the pipe, P10, with the auxiliary boiler, W. The
steam generated in the casing, K, is carried to the boiler, W, by the
pipe, P3, and from the boiler it