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 spanning fore and aft to the elevator controls which govern the ship's climbs or descents. The others are connected to the wing guides which affect the airplane's side movements. In actual use, the performance of the unit is somewhat as follows: Assuming that the ship is going eighty miles an hour and flying level, the wind pressure on the vane facing the direction of flying, drives it back against the tension of the adjustable fore and aft spring. If this has been set to the proper stiffness so that the plane is balanced at eighty miles an hour, when the nose tips down and speed is thereby increased the vane is driven farther back, tension on the spring relieved and the elevator in the back comes up, leveling the ship again to an even keel. Should the plane point up. decreasing the speed, the vane, subjected to less wind pressure, comes forward, pulling with it the control in the rear to tip it back again when the normal speed rate is restored. This same principle also is applied to the operation of the aileron controls, the side vanes being helpful in balancing the ship in turns and banks in accordance with the wind pressure to which they are exposed.







One of the sights of Oslo, Norway, is a wooden church, 800 years old and built entirely without nails. Glue, wooden pegs and braces hold the structure together. Its queer, pagodalike form illustrates the style of architecture peculiar to the period.

 

Motion pictures of the dragonfly and humming bird have been prepared by the British government in the hope that the films may reveal flying secrets that will enable engineers to design more successful helicopters and other aircraft. The dragonfly and humming bird are masters of the art of pausing in the air and this is one of the feats man has been attempting to imitate in his airships for a long time. The pictures will be analyzed carefully when shown, in an effort to learn the wing and other movements. The humming bird is regarded as one of the miracles of nature because of its skill in balancing in the air without apparent effort.

