and was broken. Its short flight disclosed that its stability was imperfect and Sir Hiram Maxim has not yet undertaken the construction of the improved machine which he is understood to have had under contemplation.
Having already built in 1872 and 1891 two full-sized flying machines with doubtful results, Mr. Ader, a French electrical inventor, built in 1897 a third machine at a cost of about $100,000 furnished by the French War Department. It was like a great bird, with 270 feet supporting surface and 1,100 pounds weight, being driven by a pair of screws actuated by a steam engine of 40 horse power which weighed about 7 pounds per horse power. Upon being tested under the supervision of the French army officers, the equilibrium was found so defective that further advance of funds was refused. The amount lifted per horse power was 27 pounds.
The data for the full-sized flying machine of Professor Langley, tested October 7 and December 8, 1903, have not yet been published. From newspaper photographs it appears to be an amplification of the models which flew successfully in 1896, and this, necessarily, would make it very frail. The failures, however, seem to have been caused by the launching gear and do not prove that this machine is worthless. Like the failures of Maxim and of Ader, it does indicate that a better design must be sought for, and that the first requisites are that the machine shall be stable in the air, shall be quite under the control of its operator, and that he, paradoxical as it may appear, shall have acquired thorough experience in managing it before he attempts to fly with it.
This was the kind of practical efficiency acquired by the Wright Brothers, whose flying machine was successfully tested on the seventeenth of December. For three years they experimented with gliding machines, as will be described farther on, and it was only after they had obtained thorough command of their movements in the air that they ventured to add a motor. How they accomplished this must be reserved for them to explain, as they are not yet ready to make known the construction of their machine nor its mode of operation. Too much praise can not be awarded to these gentlemen. Being accomplished mechanics, they designed and built the apparatus, applying thereto a new and effective mode of control of their own. They learned its use at considerable personal risk of accident. They planned and built the motor, having found none in the market deemed suitable. They evolved a novel and superior form of propeller; and all this was done with their own hands, without financial help from anybody.
Meantime it is interesting to trace the evolution which has led to this result and the successive steps which have been taken by others.
It is not enough to design and build an adequate flying machine; one must know how to use it. There is a bit of tuition which most
