Although everything induced them to hasten--for they feared another inventor might forestall them with a power-driven craft--the Wrights still went methodically to work, refusing to use a motor until they had gained a fuller knowledge of the air. So they built more gliders, and with one of them--that used in 1902--they were able to make over a thousand flights. Only once, in all their practice, did they come near disaster; and this was one day when Orville was testing a machine. The accident was described by Wilbur Wright: “My brother Orville started on a flight with one wing slightly higher than the other. This caused the machine to veer to the left. He waited a moment to see whether it would right itself, but finding that it did not, then decided to apply the control. At the very instant he did this, however, the right wing most unexpectedly rose much higher than before, and led him to think that possibly he had made a mistake. A moment of thought was required to assure himself that he had made the right motion, and another to increase the movement. Meanwhile he had neglected the front rudder, by which the fore-and-aft balance was maintained. The machine turned up in front more and more till it assumed a most dangerous attitude. We who were on the ground noticed this in advance of the aviator, who was thoroughly absorbed in the attempt to restore the lateral balance, but our shouts of alarm were drowned by the howling of the wind. It was only when the machine came to a stop and started backward that he at length realised the true situation. From the height of nearly 30 feet the machine sailed diagonally backward till it struck the ground. The unlucky aeronaut had time for one hasty glance behind him, and the next instant found himself the centre of a mass of fluttering wreckage. How he escaped injury I do not know, but afterwards he was unable to show a scratch or bruise anywhere, though his clothes were torn in one place.” The amount of practice the brothers obtained began to tell its tale, and they became sufficiently experienced to glide in winds of 37 miles an hour. It was Wilbur who, emphasising this need for constant flying, declared: “By long practice, the management of a machine should become as instinctive as the balancing movements a man unconsciously employs with every step in walking.”