. . .American" Colt Machine-gun partly broken away to show the Operating Mechanism Gas from port A pushes down piston B, rocking lever C, which compresses coil-spring D. The cartridge fed into the gun by wheel E, is extracted by F, raised by G to breech H, and rammed in by bolt I. J, piston firing-hammer.

The French in particular used this type of mortar and the air-pump was used to compress the air that propelled the shell or aërial torpedo, or else the propelling charge was taken from a compressed-air tank. Carbon-dioxide, the gas used in soda-water, is commonly stored in tanks under high pressure and this gas was sometimes used in place of compressed air. When the gas in the tank was exhausted the latter could be recharged with air by using a hand-pump. Two or three hundred strokes of the pump would give a pressure of one hundred and twenty to one hundred and fifty pounds per inch,38 and would supply enough air to discharge a number of shell. The air was let . . . Read More