In this country the Wright brothers, Orville and Wilbur, took up the work of Lilienthal and they, too, undertook to learn to fly before they built a flying machine. In all his years of experiment, Lilienthal did not have more than five hours of experience in the air. The Wright brothers determined to spend more time in the air and less in theoretical speculations at home, so they built a gliding machine that would sustain a man at a speed of eighteen miles per hour and picked out a spot on the Atlantic coast where they were assured of fairly constant winds of sixteen to twenty-five miles per hour. At first the machine was used as a kite and various experiments were made in balancing it. Then short gliding flights were made from the tops of the sand dunes. Not until the art of balancing the glider and controlling it in unsteady air currents was any attempt made at building a motor-driven flying machine. It was by these experiments that the Wright brothers discovered the system of warping the wings so as to preserve the lateral balance of the machine. After several seasons of experimental gliding, and not until they felt that they had learned how to fly, was a power machine built. This made its first flight on December 17, 1903. The first flight lasted only twelve seconds, while the fourth flight lasted fifty-nine seconds. Many months were spent in perfecting the machine and in solving the various problems of flight, and not until September, 1905, did the Wright brothers feel that they had mastered the art of flying. After that three years elapsed before the world was actually convinced of the reality of airplane flight and recognized the work of the pioneers. TRANSATLANTIC AEROPLANE FLIGHTS The development of the heavier-than-air machine is so recent and is still advancing so rapidly that we dare not give more than a brief outline of its progress here. The more important advances are familiar to most of us and a record of achievements to-day will be hopelessly out of date to-morrow. The war gave a tremendous impetus to flying. Pilots were trained by the thousand. Machines grew in speed up to 150 miles per hour. Huge bombing machines were built, with a wing spread of over 125 feet, and weighing ten to fifteen tons. These were capable of carrying a load of four to five tons. The first flight across the Atlantic was made in June, 1919, by the United States navy flying boat NC-4, which flew to Newfoundland, then to the Azores, and from there to Lisbon, Portugal. The trip was finally completed by a flight to Plymouth, England.