Page:Popular Science Monthly Volume 90.djvu/871

 Popular Science Monthly

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��A New Airplane Wheel Which Absorbs Shocks

N all wheeled vehicles it is essential that shocks should be absorbed as far as possible by the tires them- selves. In other words, the brunt of the shock should be absorbed before it is com- municated to the springs and thus to the body of the vehicle itself. For, when the axle and the wheel are set in vibration, the springs, no matter how plastic, will com- municate a part of that vibration, to the body. This is equally as true of airplanes as of automobiles.

With pneumatic tires the main force of a co'ncussion is immediately absorbed by the resilient rubber. That is one reason why airplane wheels are equipped with pneumatic tires. No wheels are exposed to such severe shocks as airplane wheels. Indeed, even the ball bearings in such wheels have been broken in making landings, so great is the force of the impact. The blow given to an air- plane wheel when landing is severe, and the ground over which it travels before it comes to a rest is rough. Thus a wheel to bear up under such abuse must not only be able to withstand a crushing force but it must absorb sidewise blows as well. The ver^^ best and most up-to-date automobile spring device is of little permanent value, therefore, to the airplane.

The new airplane wheel illustrated is said to meet all these requirements. It absorbs shocks be- fore they reach the axle and reduces bouncing to a mini- mum. Even over uneven surfaces it .'.tTords easy riding for the aviator. Thus it is possible for the airplane to start and land on rough ground. Further- more, with all violent shocks absorbed by the wheel before they are communicated to the body, the lifeof the airplane is noticeably lengthened and its usefulness enhanced.

����The two front wheels of the airplane sustain practically the entire weight and receive the roughest kind of usage

The new airplane wheel which is so designed that it will absorb shocks and reduce bouncing to a minimum

��The Re-Inking Roller for

Typewriters. It Saves the Cost

of a Dozen Ribbons

WHEN the ribbon on your typewriter has dried you can ink it again. The inking device consists of a small roller to which the ink is fed by a sort of fountain- pen arrangement. The ink is poured in the cylinder back of the roller. A short padding of felt juts from the end of the cylinder on to the roller. This piece of felt not only prevents the ink leaking out but.

like a wick, it keeps the roller moistened. When the ribbon is run through the machine against the turning roller, it is thoroughly inked. If the rib- bons are handled carefully the de- vice will save the cost of a dozen new ones and give service indefinitely. A specially prepared ink is used. It will not smudge and it is easily absorbed, so that the type striking against the ribbon give clear cut, neat letters.

��The felt wick feeds the ink from the holder to the roller. Drawing a ribbon over the roller makes it as good as new

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