Page:Popular Science Monthly Volume 91.djvu/601

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Popular Science Mouth ly

A New Zinc Product Which Is a Substitute for Tinfoil

FROM Breslau, Germany, comes a report of a substitute for tinfoil which has been successfully manufactured from zinc by a Ger- man experimenter. The zinc prod- uct is so similar in appearance and general characteristics to the tinfoil that the two are scarcely distinguishable. The manufacturer claims that the zinc foil will answer every purpose for which tinfoil is ordinarily employed.

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��This Tire Pump Gets Power from the Engine Crankshaft

AUTOMOBILISTS, take notice l of the tire pump illustrated. It fits any make of car and particu- larly cars which were not originally fitted with power tire-pumps under the en- gine hoods. It is merely slipped over the end of the engine crankshaft extend- ing out in front of the radiator. By starting the engine and attaching a hose from the pump to the nipple, the tire is inflated in a few moments. This done, the pump is removed just as easily and put back in the tool box until required again.

It is impossible to pump oil into the tire with the air. Oil rots rubber inner tubes. No oil can find its way to the tire because a tight, vibrating diaphragm is used. The air is sucked in on one side of the diaphragm and then forced out on the same side, in which no oil is used. There is only one lubri- cated part of the pump, and thatisthelower end of the con- necting rod bearing which causes the dia- phragm to vi- brate. This bearing is oiled, with grease from an out- side grease cup.

����At left: Part cross-sectional view of the pump, showing the cylinderlike casing with a rubber diaphragm held between top and cover. This diaphragm is vi- brated up and down by means of a lower semi-spherical cup fast- ened to the top of an eccentric connecting rod around the shaft of the pump which is connected with the engine crankshaft. The air is sucked in through a small valve in the cover on the down stroke of the rod and forced out on the upstroke as the diaphragm is also forced up. A check valve in the outlet valve prevents the air from backing up. Above: The pump in use on the car

��Moving Targets to Quicken the Eye and Steady the Aim

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���A hand pulley improvised from a bicycle wheel is used to drive the target by means of a flexible cable

��lIFLE clubs are adopting the moving field targets so popular in British shooting ranges to quicken the eye and add zest to rifle and revolver practice.

The "deers" used are generally five feet long and are constructed of heavy plaster- board, painted a light brown and suspended by two wires which ride on a trolley wire which is about thirty yards in length. The driving power is fur- nished by a flexible cable attached to the front and rear of the deer.

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