Louis Pierre Mouillard, a Frenchman, who had observed that large birds in flight, while seeming at rest, could go forward against the wind without a stroke of the wings, constructed a number of gliders built on the principle of bird wings, and experimented with gliding. He published a work called “L’Empire de l’Air,” which inspired many late experiments with gliders.
The net results of all these designs and experiments of these inventors demonstrated that thin, rigid surfaces of a certain shape, structure, and design could support weights when driven through the air at a sufficient velocity. Further than that they contributed practically nothing to the science of aviation.
As a matter of fact, it was toward the close of the nineteenth century before means were found to make an aeroplane rise from the ground, maintain its equilibrium. These latter-day pioneers of aviation were divided into two schools. The first sought to achieve soaring flights by means of large kitelike apparatus, which enabled them to fly in the air against winds, their machines being lifted up and supported by the inertia of the air as kites are. The second sought to develop power flight, that is, to send their kitelike machines through the air at high speed, being tracted or propelled by revolving screws actuated by motor power.
The most prominent experimenters of the first glider school were Otto Lillienthal, a German, P. L. Pitcher, an Englishman, Octave Chanute, and J. J. Montgomery.
Lillienthal was the first man to accomplish successful flights by means of artificial wing surfaces. In 1894, after much experimenting, he constructed rigid wings which he held to his shoulders. He used to run down hills with them until the velocity he was moving at would catch the air and lift him completely off the ground. By observation of birds he saw that their wings were arched, which suggested reason for failures of previous experiments in this line; so afterward his planes were arched also. He was the first man to be lifted off the ground by plane surfaces, and to demonstrate that arched surfaces were necessary to sustained flight of heavier-than-air craft.
To the rigid wings Lillienthal fastened a rigid tail and this constituted his glider. There were no control levers and the only way he could steer was by shifting the balance, by use of his legs, in one direction or another. By means of an artificial hill he had constructed he could coast downward for some distance without striking the ground. He was unfortunately killed in one of these experiments in 1896.
Chanute’s experiments in gliding were similar to Lillienthal’s, but they were conducted on the sand-dunes along Lake Michigan, near Chicago. His apparatus was more strongly constructed, of trussed biplane type—a construction suggested to him by his experience in bridge building, and one which persists to-day as the basis of strength in our present military biplanes. In design it was similar to a box kite, and it was the kind which the Wrights adopted for their experiments.
The leaders of the second school were: Clement Ader (1890-97), Sir Hiram Stevens Maxim (1890-94), and Samuel Pierpont Langley (1895-1903).
Clement Ader, the famous French scientist, under the auspices of the French Government, conducted experiments from 1890 to 1897. In 1890 he filled his Arion, a boat-shaped machine with two propellers, with a steam-engine, but the apparatus never flew. He finished his next machine in 1897 after six years of hard work. It was large enough to carry a man, but, like its predecessor, it never left the ground, and the French Government refused to support his experiments further.
While Ader was making his experiments in France, Sir Hiram S. Maxim was at work constructing a large multiplane for the English Government, which he fitted with two steam-engines of 175 horse-power. But like Ader’s experiments it toppled over at the first trial and was badly damaged, and the British Government refused further backing.