Page:Popular Science Monthly Volume 91.djvu/703

 Popular Science Monthly

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��Open Your Mouth and Let the Doctor Flashlight Its Interior

AN interesting little de- L vice recently invented for the convenience of physi- cians and dentists, is an automatic mouth in- specting lamp.

A small electric bulb is fitted into a short tube which is itself hinged to a larger cylin- der containing the stan- dard flashlight batteries. A wooden tongue-de- presser is attached to the tube. When the surgeon presses down your tongue with this, the tube is swung slight- ly on its hinge. This ac- tion produces the light.

���When tongue circuit

��started, this system supplies practically a constant circulation, so that when the en- gine is working under a heavier load than usual, and therefore requires a greater circulation, it does not get it. This lack causes over- heating.

This deficiency is overcome by the simple pump shown below. It consists of a screw- like blade working in a short barrel inserted in the regular Ford water line between the radi- ator and the engine. The blade is revolved by means of a small belt and pulley driven by the big radiator fen- shaft. The faster the engine revolves the more wateriscirculated.

��the surgeon depresses your , the action closes an electric and illuminates your mouth

��Preventing the Ford Engine from Over- heating—A Simple Pump Does It

THE engine of the Ford car often over- heats in the hot weather when driving fast or work- ing under a hard pull be- cause of the thermo-sy- phon water cooling sys- tem e m - ployed. In this system the water cir- culates from the radiator to the cylin- ders and back again in ac- cordance with the natural law which causes hot water to rise to the top while cold water drops to the bottom. After the en- gine is once

���The water circulates continuously from the radiator to the cylinders and back, forced at times by a screw- like blade which is revolved by a belt and pulley

��Lucky and Unlucky Telephone Num- bers — In Japan They Affect Your Bill

OUR only unlucky number is 13. In Japan they have two unlucky num- bers — 42 and 49. Nobody wants either of these num- bers for a tele- phone call, simply be- cause the for- mer is pro- n o u n c e d "shini, "which means "to - die" and the latter is pro- n o u n c e d ' ' s h i ku, ' ' which means "death." The luckiest tel- phone num- ber in the esti- mation of the J a pa n ese business man iseight, which suggests pros- perity.

��All the specialized knowledge and information of the editorial staff of the Popular Science Monthly is at your disposal. Write to the editor if you think he can help you.

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