feet in length, with two sets of
wings, the pair in front measuring forty feet from tip to tip. On May
6, 1896, this model was launched over the Potomac River. It flew half
a mile in a minute and a half. When its fuel and water gave out, it
descended gently to the river's surface. In November Langley launched
another model which flew for three-quarters of a mile at a speed of
thirty miles an hour. These tests demonstrated the practicability of
artificial flight.

The Spanish-American War found the military observation balloon doing
the limited work which it had done ever since the days of Franklin.
President McKinley was keenly interested in Langley's design to build a
power-driven flying machine which would have innumerable advantages over
the balloon. The Government provided the funds and Langley took up the
problem of a flying machine large enough to carry a man. His initial
difficulty was the engine. It was plain at once that new principles of
engine construction must be adopted before a motor could be designed
of high power yet light enough to be borne in the slender body of an
airplane. The internal combustion engine had now come into use. Langley
went to Europe in 1900, seeking his motor, only to be told that what he
sought was impossible.

His assistant, Charles M. Manly, meanwhile found a builder of engines
in America who was willing to make the attempt. But, after two years of
waiting for it, the engine proved a failure. Manly then had the several
parts of it, which he deemed hopeful, transported to Washington, and
there at the Smithsonian Institution he labored and experimented until
he evolved a light and powerful gasoline motor. In October, 1903, the
test was made, with Manly aboard of the machine. The failure which
resulted was due solely to the clumsy launching apparatus. The airplane
was damaged as it rushed forward before beginning to soar; and, as
it rose, it turned over and plunged into the river. The loyal and
enthusiastic Manly, who was fortunately a good diver and swimmer,
hastily dried himself and gave out a reassuring statement to the
representatives of the press and to the officers of the Board of
Ordnance gathered to witness the flight.

A second failure in December convinced spectators that man was never
intended to fly. The newspapers let loose such a storm of ridicule upon
Langley and his machine, with charges as to the waste of public funds,
that the Government refused to assist him furt