The Wright Brothers, for Wilbur Wright was joined by his brother Orville in the experiments, were the first to reap success from the seeds of Dr. Langley’s sowing. Mr. Chanute had been experimenting with a biplane form of motorless glider with little success, because of lack of means for balancing the machines in the air, until he was joined by a former employe of Dr. Langley. He appears to have imparted to Mr. Chanute the secret of the stabilizing effect of the Penaud tail, or combination of vertical and horizontal rudders. Thereafter hundreds of successful gliding flights were made with the Chanute biplane, though Chanute seems not to have grasped the full significance of the rudders,--though it was well understood by Dr. Langley. To the Chanute machine, as described to him, Mr. Wright added first the idea of flexing or warping the wings, after the fashion set by the Lilienthals. He found, however, as Dr. Langley had found years before, that in attempting to correct lateral balance in this way caused the aeroplane to swerve to such an extent that the fixed vertical rudder, as originally employed, did not correct the upsetting tendency that was developed. Mr. Wright then arranged his rudder in such a way that when the wing was warped the rudder turned in a way to offset the swerve. This combination was patented all over the world and has resulted in much complicated litigation. To this machine the Wright Brothers added a gasoline motor in December, 1903, and with it made numerous flights during 1904-5. Their claims were not generally credited however until a later date for their experiments had been conducted with considerable secrecy, and during 1906, 1907 and until late in 1908 they did no more flying. In the meantime M. Bleriot had made a copy of one of the early Langley tandem monoplane models and made some fairly successful flights with it in Europe. Later, as gasoline motors developed in power for weight, he reduced the rear surface until the modern monoplane evolved. While Bleriot was working in Europe, Dr. Bell’s Aerial Experiment Association in America was evolving still another type of machine, and the members of the association made the first successful public flights in America. Mr. Curtiss won the Scientific American Trophy for the first time on July 4th, 1908, by a straightaway flight of more than a kilometer. The balancing system employed by the A. E. A. differed from that employed by the Wrights and by Bleriot in that small auxiliary planes took the place of warping planes for righting the machine. This they claimed to be a superior method, first, because it eliminated the use of the rudder as being absolutely essential to the balance of the machine; second, because it enabled them to make the main planes rigid throughout, and consequently stronger than the flexible planes.