Page:Popular Science Monthly Volume 90.djvu/700

 684

��Popular Science Monthly

��An Electric Signaling System for the Automobile

���Each arrow is mounted on a small cog-wheel which meshes in a horizontal rack gear, the ends of which act as arma- tures in two solenoid coils

��ANEW type of automobile signal designed to make the course of the car perfectly clear to the traffic officer or following vehicle, employs fairly large arrow dials at front and rear to indicate turns, and a mechanically-operated hand at the rear to indicate a stop. The device is operated by electric current obtained from the storage battery now usually fitted on cars and is manipulated from a small control-box mounted on the steering- column directly below the driver's hand- wheel.

Each dial is glass-covered, like a circular thermometer, to keep out dust and dirt. Each is pro- vided with a large black arrow, which stands out against a white background and is there- fore discernible at a sufficient distance to avoid collisions at the rear. Similarly the arrow on the front dial suffices to signal to the traffic officer the direction in which it is desired to turn.

Both dials are electrically lighted at night by means of three small bulbs. The front dial is held in front of the radiator by means of a clamp around the filler-cap. The rear dial is close to the license-plate, the electric bulb illuminating it also serving to light up the white hand with the word "Stop" in

���large, black easily distinguished letters. The front and rear dials are wired up on the same circuit so that the arrows in both always point in the same direc- tion. Normally each arrow points verti- cally upward; but when it is desired to turn, the driver pushes a button on the control- board to turn them to right or left so as to indicate a turn in either direction. This is accomplished electri- cally by mounting each arrow on a small cog-wheel, which meshes in a horizontal rack-gear whose ends act as armatures in two solenoid- coils. Energizing either coil draws the rack into that coil and turns the arrow that way.

���CANVAS--

��An Ingenious Cover and Press for the Tennis Racket

AFTER hard use a tennis racket warps. . The gut becomes loose and saggy. To preserve the shape of the frame a racket press may be employed. But the press does not prevent the gut from being affected by atmospheric changes. Clearly, a moisture- proof cover is necessary.

Charles L. Bates, of Chi- cago, 111., has invented a combined press and covering which seems to meet all re- quirements. The clamping devices on most rackets pre- vent the use of any covering. . But the inventor has de- signed his cover so that it is clamped securely over the racket at the same time the press is tightened. The cov- ering protects the handle as well as the face of the racket. A pair of clamping frames He on each side of the racket frame. After they are tight- ened by wing-bolts, as il- lustrated, the cover is fastened by means of eye- lets. The clamping frames are provided with bolts large enough to fit any racket.

��A combined press and waterproof covering for the racket

�� �