rs, at least, should not be forgotten in this
connection: Nicola Tesla and Charles S. Bradley. Both of them had worked
for Edison.

The turbine (from the Latin turbo, meaning a whirlwind) is the name of
the motor which drives the great dynamos for the generation of electric
energy. It may be either a steam turbine or a water turbine. The steam
turbine of Curtis or Parsons is today the prevailing engine. But
the development of hydro-electric power has already gone far. It is
estimated that the electric energy produced in the United States by the
utilization of water powers every year equals the power product of forty
million tons of coal, or about one-tenth of the coal which is consumed
in the production of steam. Yet hydro-electricity is said to be only in
its beginnings, for not more than a tenth of the readily available water
power of the country is actually in use.

The first commercial hydro-station for the transmission of power
in America was established in 1891 at Telluride, Colorado. It was
practically duplicated in the following year at Brodie, Colorado. The
motors and generators for these stations came from the Westinghouse
plant in Pittsburgh, and Westinghouse also supplied the turbo-generators
which inaugurated, in 1895, the delivery of power from Niagara Falls.

CHAPTER X. THE CONQUEST OF THE AIR

The most popular man in Europe in the year 1783 was still the United
States Minister to France. The figure of plain Benjamin Franklin, his
broad head, with the calm, shrewd eyes peering through the bifocals
of his own invention, invested with a halo of great learning and fame,
entirely captivated the people's imagination.

As one of the American Commissioners busy with the extraordinary
problems of the Peace, Franklin might have been supposed too occupied
for excursions into the paths of science and philosophy. But the
spaciousness and orderly furnishing of his mind provided that no pursuit
of knowledge should be a digression for him. So we find him, naturally,
leaving his desk on several days of that summer and autumn and posting
off to watch the trials of a new invention; nothing less indeed than a
ship to ride the air. He found time also to describe the new invention
in letters to his friends in different parts of the world.

On the 21st of November Franklin set out for the gardens of the King's
hunting lodge in the Bois de Boulogne, on the outskirts of Paris, with
a quickened interest, a thrill of exc