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Accurate tests of pupils' hearing are possible with an instrument that transmits sound from a phonograph record through a number of headphones the children wear. The record is simply a series of numbers, spoken through a reproduction of the human voice and in constantly diminishing volume. The subjects write down what they hear, the results giving a faithful report of the acuteness of hearing in both the right and left ear. This method eliminates the guesswork usually attending ordinary whisper tests and other experiments where the acoustics of the room, the nervousness of the child and other factors are not properly taken into consideration in the final judgment.

 

For Smoother Riding in the Small Auto: Drawing to Show the "Cantilever" Springs in Place

A new idea to increase the riding comfort of the small auto, provides 200-inch springs which reach from one axle to the other, while the car is carried by a fulcrum joint just back of the engine. The springs, designed for a car having cross springs at front and rear, give the effect of double-cantilever suspension. The front spring is discarded and part of the rear spring retained. The car body is fastened to the rear spring and pivoted at a point near the dash. It is claimed the springs eliminate the usual swaying of the body and give the small car as good riding qualities as a high-priced automobile.

 

Promise of greater safety in flying is seen in a stabilizer arrangement which is reported to have proved successful in a number of tests. Its chief service is to automatically adjust the ship to correct the pressure of air currents and changes in engine speed, so that it serves as a silent pilot when the operator, for any reason, relinquishes control of the stick, yet it is said not to interfere with his actions when he assumes charge. The apparatus consists chiefly of a pillar mounted on a universal joint and with two vanes at the upper end. It is placed clear of the propeller and where no parts of the ship are likely to cause eddying. At the lower end, two sets of wires are connected, one pair 