To make a glide, the machine is taken to an elevated point on a slope, not far up to begin with. Lift the glider, get in between the arm rests, and raise the apparatus until the rests are snug under the arms. Run swiftly for a few yards and leap into the air, holding the front of the planes slightly elevated. If the weight of the body is in the right position, and the speed sufficient, the glider will take the air and sail with you down the slope. It may be necessary at first to have the help of two assistants, one at each end, to run with the glider for a good start. [Illustration: Diagram showing differing lines of flight as controlled by changing the position of the body. The wind must be blowing against the direction of flight; in the illustration this would be from left to right.] The position of the body on the arm rests can best be learned by a few experiments. No two gliders are quite alike in this respect, and no rule can be given. As to the requisite speed, it must be between 15 and 20 miles an hour; and as this speed is impossible to a man running, it is gained by gliding against the wind, and thus adding the speed of the wind to the speed of the runner. The Wrights selected the sand dunes of the North Carolina coast for their glider experiments because of the steady winds that blow in from the ocean, across the land. These winds gave them the necessary speed of air upon which to sail their gliders. The first flights attempted should be short, and as experience is gained longer ones may be essayed. Balancing the glider from side to side is accomplished by swaying the lower part of the body like a pendulum, the weight to go toward the side which has risen. Swinging the body forward on the arm rests will cause the machine to dip the planes and glide more swiftly down the incline. Holding the weight of the body back in the arm rests will cause the machine to fly on a higher path and at a slower speed. This is objectionable because the glider is more manageable at a higher speed, and therefore safer. The tendency at first is to place the weight too far back, with a consequent loss of velocity, and with that a proportionate loss of control. The proper position of the body is slightly forward of the mechanical centre of the machine. The landing is accomplished by shoving the body backward, thus tilting up the front of the plane. This checks the speed, and when the feet touch the ground a little run, while holding back, will bring the glide to an end. Landing should be practised often with brief glides until skill is gained, for it is the most difficult operation in gliding. After one becomes expert, longer flights may be secured by going to higher points for the start. From an elevation of 300 feet a glide of 1,200 feet is possible. [Illustration: Gliding with a Chanute three-decker. A start with two assistants.]