These two eminent men, who took up the subject of flying in the last decade of the last century, came to their task with great scientific knowledge. Hitherto flying was associated in the minds of the public with failure and folly. Indeed, Sir Hiram Maxim once remarked that at the time he took up the subject it was almost considered a disgrace to any one to think of it. It was thought ‘quite out of the practical question.’ But the two great men now in mind were not to be turned aside by ridicule. ‘They rescued aeronautics from a fallen position, and fired in its cause the enthusiasm of men of light and learning.’ Sir Hiram Maxim’s experiments were on a large scale. He built the largest flying-machine that had then been constructed. It had 4,000 feet of supporting surface and weighed 8,000 lbs.; the screw propellers measured 17 feet 11 inches in diameter, the width of the blade at the tip being 5 feet. The boiler was of 363 h.-p. This remarkable machine had wheels and a railway line, and was restrained from premature flight by a system of wooden rails. But it proved unruly. It burst through the wooden rails, and flew in a wholly unexpected fashion for 300 feet! Professor Langley’s experiments carried flying still further. In 1896 he built a machine that flew for more than three-quarters of a mile. In this machine there was only 70 square feet of supporting surface, and the weight was only 72 lbs. It had a 1 h.-p. engine, weighing 7 lbs. But Professor Langley had still to build a machine that would carry a man. This he did in due course, but when the machine was being put to the test over water, and at the very moment of being launched, it caught in the launching ways and was pulled into the water. Progress had, however, been made, and it is well worthy of note that of recent date an American aviator has unearthed Langley’s machine and flown on it, thus giving posthumous honour to the inventor. Following the professor’s efforts, further progress was made by Mr. Octava Chanute, who introduced the important principle of making moveable surfaces. He also made use of superposed surfaces. But it was reserved for the two famous aviators, the brothers Wright, to bring the desired conquest of the air to a definite point. Their first practical experiment was with gliding machines at Kitty Hawk, North Carolina, in 1900. They endeavoured with comparatively small surfaces to raise their machines like a kite by the wind. But they found that the wind was not always in their favour and often blew too strongly for their method. Consequently, they abandoned the idea, and resorted to flight by gliding. Their machines now had two superposed surfaces. They also introduced two highly important principles, namely, a horizontal rudder in front for controlling the vertical movements, and the principle of warping or flexing one wing or the other for steering purposes. Later a vertical rudder was added.