larger on the outside, so that in turning the wide curves of the
railroad the whole machine slides to the inside, bringing to bear the
large diameter of the outer wheel and the small diameter of the inner,
the wheels being fixed to a solid axle.

The steam machine can always be distinguished by the thin stream of
white vapour that escapes from the rear or underneath while it is in
motion and also, as a rule, when it is at rest.

The motor of a steam vehicle always stops when the machine is not
moving, which is another distinguishing feature, as the gasoline motors
run continually, or at least unless the car is left standing for a long
time.

As the owners of different makes of bicycles formerly wrangled over the
merits of their respective machines, so now motor-car owners discuss the
value of the different powers--steam, gasoline, and electricity.

Though steam was the propelling force of the earliest automobiles, and
the power best understood, it was the perfection of the gasoline motor
that revived the interest in self-propelled vehicles and set the
inventors to work.

A gasoline motor is somewhat like a gun--the explosion of the gas in the
motor-cylinder pushes the piston (which may be likened to the
projectile), and the power thus generated turns a crank and drives the
wheels.

The gasoline motor is the lightest power-generator that has yet been
discovered, and it is this characteristic that makes it particularly