Show device converts auto cylinder into air pump A new device that can be screwed into the spark plug hole of one of the autos cylinders turns turn that cylinder into an air pump th that t will produce two and a halt half cubic feet of f free air per minute this much germ at air ir is sufficient to spray oil paint germicide insecticide and liquids says popular science monthly on the down stroke of the piston in the cylinder to which the device Is fitted the piston sucks in outside air air through a spring operated valve on the up stroke this valve closes and another opens ril lowing the air to flow into a storage tank or into the pipe leading to the spray equipment if m more ore air Is needed than can be obtain obtained d from one cylinder in this way two or of the devices can be used at the same time so as to double the output it Is designed to wa work rk at an engine speed equivalent to a road speed of 20 miles an hour |