ndonment of the internal combustion idea, and the mechanical
difficulties with steam being less, the steam engine became successful,
and triumphed over its rival. The knowledge and skill gained in the
construction of steam engines made it possible once again to attack the
more difficult problem, and simultaneously with the introduction and
perfecting of the steam engine, the gas engine idea became more and more
possible, the practicable stage commencing with Lenoir and continuing with
Hugon, Millein, Otto and Langen, F.H. Wenham, then Otto and Clerk. In
1860, 95 cubic feet of gas produced one horse power for an hour; in 1867,
40 cubic feet accomplished the same thing; and now (1885) we can get one
horse power for an hour for from 15 to 20 cubic feet of gas, depending on
the size of the engine used.

Considered as a heat engine, the gas engine is now twice as efficient as
the very best modern steam engine. It is true the fuel used at present
is more expensive than coal, and for large powers the steam engine is
the best because of this. But the way is clearing to change this. Gas
engines as at present, if supplied with producer gas, produced direct
from coal without leaving any coke, as is done in the Siemens, the
Wilson, and the Dawson producers, will give power at one-half the cost
of steam power. They will use 7/8 of a pound of coal per horse power per
hour, instead of 1-3/4 lb., as is done in the best steam engines. The
only producer that makes gas for gas engines at present is the Dawson,
and in it anthracite is used, because of the difficulty of getting rid
of the tar coming from the Siemens and Wilson producers, using any
ordinary slack.

When this difficulty has been overcome, and that it will be overcome there
can be no manner of doubt, gas engines will rapidly displace the steam
engine, because a gas engine with a gas producer, producing gas from any
ordinary coal with the same ease as steam is produced from a boiler, will
be much safer, and will use one-half the fuel of the very best steam
engines for equal power. The first cost also will not be greater than that
of steam. The engine itself will be more expensive than a steam engine of
equal power, but the gas producer will be less expensive than the boiler
at present. Perfect as the gas engine now is, considered as a machine for
converting heat into work, the possibility of great development is not yet
exhausted. Its economy may be increased two or even three