e
lifting power. This was demonstrated by Henson, in 1842,
Stringfellow, in 1847, Wenham, who arranged his planes like slats in
a Venetian blind and first applied the modern term "aeroplane" to
his invention, and Sir Hiram Maxim, who built in 1890 the most
complicated and impressive looking 'plane the world has yet seen.
But though each of these inventors proved the theorem that a
heavier-than-air machine could be made to fly, all failed to get
practical results because no motor had then been invented which
combined the necessary lightness with the generation of the required
power.

In America we like to think of the brothers Wright as being the true
inventors of the airplane. And indeed they did first bring it to the
point of usefulness, and alone among the many pioneers lived to see
the adoption of their device by many nations for serious practical
use. But it would be unjust to claim for them entire priority in the
field of the glider and the heavier-than-air machine. Professor
Langley preceded them with an airplane which, dismissed with
ridicule as a failure in his day, was long after his death equipped
with a lighter motor and flown by Glenn Curtis, who declared that
the scientist had solved the problem, had only the explosive engine
been perfected in his time.

Despite, however, the early period of the successful experiments of
the Wrights and Professor Langley, it would be unjust for America to
arrogate to herself entire priority in airplane invention. Any story
of that achievement which leaves out Lilienthal, the German, and
Pilcher, the Englishman, is a record in which the truth is
subordinated to national pride.

[Illustration: Langley's Airplane.]

Otto Lilienthal and his brother Gustav--the two like the Wrights
were always associated in their aviation work--had been studying
long the problem of flight when in 1889 they jointly published their
book _Bird Flight as the Basis of the Flying Art_. Their
investigations were wholly into the problem of flight without a
motor. At the outset they even harked back to the long-abandoned
theory that man could raise himself by mere muscular effort, and
Otto spent many hours suspended at the end of a rope flapping
frantically a pair of wings before he abandoned this effort as
futile. Convinced that the soaring or gliding of the birds was the
feat to emulate, he made himself a pair of fixed, bat-like wings
formed of a light fabric stretched over a willow frame. A tai