Page:Popular Science Monthly Volume 89.djvu/709

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Popular Science Monthly


��controlled by a pilot carried along on its flight, we can well believe that he has not underestimatetl human courage.

He builds his torpedo so that the part in which the pilot sits may be detached after the explosive charge has been released to proceed under its own auto- matic control.

The detachable, [)ilot-carrying portion is attached to the main body of the torpedo and the various levers and controlling de\"ices are all within the reach of the operator. When the torpedo is traveling on the surface of the water, partly submerged, the com- pressed air used by the engine may be taken from an air-chamber, which is in communication with the atmosphere, through vertical tubes resembling peri- scopes. When the torpedo is to be submerged to a greater depth the tubes are lowered and the engine is then supplied with gas from a compressed-gas tank. The depth of submergence ma\- be regulated by the inclination of planes at the side of the body.

When the torpedo has been brought to proper striking distance by the pilot, who has meanwhile fixed the control for the correct course and the proper submergence, a rod is operated which causes pressure from the compressed air tank to separate the torpedo body from the pilot section. As soon as the pilot section is free from the main body of the torpedo, the weight of the conning- tower portion causes the section to turn over, the top now acting as a keel. After opening the hatch-way, the pilot maneuvers his way back to his vessel.

��The Air-Glider Which a German Boy Is Building

WHILE his father and big brothers are away fighting for the Kaiser, the German boy is taking a renewed interest in aeronautics. The accompany- ing photograph shows a new one-man aeroplane or glider which contains prin- ciples of construction embodied in all the flying machines which are making history these days. The glider is thoroughly typical of our modern aeroplane.

Its perfect rigidity under varying pressures and its never-changing form of wing-surface made possible by the thick, solid middle frame, the deep trussing and the large number of wing- ribs, insure a safe and enjoyable sport for the boy. Although this glider has the appearance of being clumsy and hea\y, it is of just the right weight to rise in a light wind and earn,- the flier a considerable distance.

There is a noticeable contrast between this glider and the Lilienthal models, which are overloaded by the weight of the operator. The latter are much lighter in construction, since the frame is made of willow wands. Professor Langley told in 1896 how attempts to fly his models were frustrated by an uncontrollable "steering" action of wings that were imperceptibly changing shape under pressures. It is interesting to note that the Wright brothers, pioneers of aviation, first learned the rudiments of flying by using gliders of their own con- struction.

���Although this glider appears clumsy it is of just the right weight to rise in a light wind. The large number of wing-ribs and the solid middle frame insure the safety of the flier

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