These wind-tunnel experiments in the bicycle shop were carried on for only a little more than two months, and were ended before Christmas, 1901. The Wrights discontinued them with great reluctance; but, after all, they were still in the bicycle business, still obliged to give thought to their means for earning a living, and with no idea that this scientific research could ever be financially profitable. In those few weeks, however, they had accomplished something of almost incalculable importance. They had not only made the first wind-tunnel in which miniature wings were accurately tested, but were the first men in all the world to compile tables of figures from which one might design an airplane that could fly. Even today, in wind-tunnels used in various aeronautical laboratories, equipped with the most elaborate and delicate instruments modern science can provide, the refinements obtained over the Wrights’ figures for the same shapes of surfaces are surprisingly small. But it is doubtful if the difficulties and full value of the Wrights’ scientific researches within their bicycle shop are yet appreciated. The world knows they were the first to build a machine capable of sustained flight and the first actually to fly; but it is not fully aware of all the tedious, grueling scientific laboratory work they had to do before flight was possible. Important as was the system of control with which the Wrights’ name has been connected, it would not have given them success without their wind-tunnel work which enabled them to design a machine that would lift itself. The Wrights had a double reason for making sure of their figures. With little money to spend on a hobby, it was much cheaper to rectify mistakes on paper than after the idea was put into material form. They knew that if they should decide to go on to further gliding attempts, they could not afford to spend much more money on apparatus built according to unreliable data. After compiling their own tables of figures, the Wrights gave copies of them to their friend Chanute and others interested in the problem of aerodynamics. Chanute well knew that the Wrights now had knowledge of aeronautics far beyond that of anyone else in the world, and he felt that for them to go on with their experiments was almost a duty. He much regretted, in the interest of science, he said, that they had reached a stopping-place, for he was sure further experiments on their part promised “important results.”