practice. They figured out that Lilienthal, up to the time of his death the most famous exponent of the gliding art, had spent only about five hours in actual gliding through the air. The wonder was not that he had done so little, but that he had accomplished so much. It would not be considered at all safe for a bicycle rider to attempt to ride through a crowded city street after only five hours practice, spread out in bits of ten seconds each over a period of five years. Yet Lilienthal with this brief practice was remarkably successful in meeting the fluctuations and eddies of wind gusts. The Wrights argued that if some method could be found whereby it would be possible to practice by the hour instead of by the second, there would be hope of advancing the solution of a very difficult problem. It seemed to them that it would be feasible to do this by building a machine which would be sustained at a speed of some eighteen miles per hour, and then finding a locality where winds of this velocity were common. With these conditions, a rope attached to a machine to keep it from floating backward, would answer very nearly the same purpose as a propeller driven by a motor, and it would be possible to practice by the hour, and without any serious danger, as it would not be necessary to rise far from the ground, and the machine would not have any forward motion at all. They found, according to

the tables of air pressure on curved wing surfaces accepted at that time, that a machine with 200 square feet of wing surface would be sufficient for their purpose; and that places would easily be found along the Atlantic coast where winds of sixteen to twentyfive miles an hour were not at all uncommon. When the winds were low, it was their plan to glide from the tops of sandhills, and when they were sufficiently strong to use a rope for their motor and fly over one spot.

They soon settled on a spot which would answer their desire for solitude and satisfy their very ideal of metereological and geographical requirements. This was on a strip of sand, somewhat gruesomely termed Kill Devil Hill, near the little settlement of Kitty Hawk, North Carolina, situated on the narrow strip of land dividing Albemarle Sound from the Atlantic. When in after years correspondents of the great metropolitan newspapers were detailed to follow the flights attracting world wide attention, they found that even the General Manager of the Pennsylvania Railroad could scarcely tell them where Kitty Hawk was and how to get there. Byron R. Newton, former Collector of the Port of New York, and in his younger days aviation reporter of the New York Herald, has graphically described his pilgrimage to this isolated spot. "It took me three days to get there," said Mr.

Newton in some recent reminiscences.

"The place

was in the sand dunes on a stretch of beach along the North Carolina coast. To get there we had to go to Elizabeth City, Virginia, thence to the head of the Dismal Swamp, then to Pamlico, Albemarle and Roanoke Sound, landing at Manteo, on Roanoke Island." And describing his efforts to watch the un. suspecting Wright brothers at their work: "The Wrights were still on Kill Devil Hill, a strip of sand just across the sound. To get there we had to leave each morning at four o'clock, cross the sound in a slow launch or row-boat, walk six miles through sandhill and jungle, and then hide in the woods a mile distant all day to watch their movements, with endless numbers of moccasins, black snakes, wild pigs and other things all round us.'

But the Kill Devil sandhills, the principal of which is slightly over a hundred feet in height, with the right slope of ten degrees, were ideal for the Wrights' purpose. Disregarding their desolate surroundings, they settled down in a rough shack and set to work.

The original plan of flying their glider as a kite proved unsuccessful. The tables of air pressure the Wrights used were apparently in error, and the lifting capacity of the kite flights fell far short of expectation. They then turned to gliding-coasting downhill on air-as the only method of getting the

desired practice in balancing a machine. After a few minutes practice they were able to make glides of over 300 feet, and in a few days were safely operating in 27-mile winds. The experiments taught the Wrights many things, and in particular the absolute necessity of a steering rudder, and the fact that on the curved surface of the wind the center of pressure moved back when the inclination of the wing was small, so that a machine would nose dangerously down unless the pilot stopped the movement promptly with his elevator.

Wilbur Wright has provided a fairly full account of what was accomplished in the 1901 experiments. The record shows an amount of patient and painstaking work almost beyond belief-it was no question of making a plane and launching it, but was a business of trial and error, investigation and tabulation of detail, and the rejection, time after time, of previously accepted theories, till the brothers must have felt that the solid earth was no longer secure at times.

The experiments of 1901 were, however, far from encouraging. Although Mr. Chanute, a man of sixty, too old to fly himself, but generously and wisely encouraging the younger men, assured the Wrights that both in control and in every other respect they had gone further than any of their predecessors, yet they saw that the calculations upon which all flying ma

chines had been based were unreliable, and that all were simply groping in the dark. Having set out with absolute faith in the existing scientific data, they were driven to doubt one thing after another, till finally after two years of experiment, they cast it all aside and decided to rely entirely upon their own investigations.

And herein Wilbur and Orville Wright showed another instance of the greatness of their souls. These "Wright boys of Dayton," as they were called contemptuously for many years by multitudes of envious inventors, without any great education back of them, without any special training in scientific investigation, found errors in the works of great authorities of the French Academy, of the Royal Aeronautical Society, of the great Langley himself, and dared to challenge them. And without any government subsidy, relying solely on their own slender resources, they achieved results in the fundamental science of air flow, which stand correct to the present day.

It is true that they had taken up aeronauties merely as a sport. They entered reluctantly upon the scientific side of it. But they soon found the work so fascinating that they were drawn into it deeper and deeper. Two testing machines were built, which the Wrights believed would avoid the errors to which the measurements of others had been subject. After