gradually to 25, 50 and 100 horses with a motor having a single cylinder
of a diameter of 57 centimeters.

[Illustration: FIG. 1.--CORLISS ENGINE AND BOILER OF 100 INDICATED
H.P.--ELEVATION AND PLAN.

A, cylinder; B, condenser; C, boiler; R, feed water heater; D, chimney.]

But these results did not suffice, and it was desired to do better still
by dispensing with the use of high priced illuminating gas. An endeavor
was made to obviate the difficulty by manufacturing a special gas for
the motive power, as steam is produced for the same object, by
distilling coal, carbureting air, producing water gas by the Dowson
process, and by other equivalent processes.

The strides made in this direction were finally crowned with success,
and the results obtained in the recent experiments due to Mr. Aimé Witz,
an undoubted authority in the matter, permit of affirming that now and
hereafter, in many circumstances, a gas generator supplying a gas motor
will be able to advantageously dethrone a steam boiler supplying a steam
engine of the same power.

These conclusions, which tend to nothing less than to limit the reign of
the steam engine, are confirmed on the one hand by an experiment carried
on for the last two years in the Barataud flour mill of Marseilles,
where a 50 h.p. "Simplex" motor has been running day and night for
several months without stopping, and consuming but about 500 grammes of
English anthracite per effective horse hour, and, on another hand, by
some personal experiments of Mr. Witz's, to which we shall shortly
advert, and whence there results a sensibly equivalent production for a