Its rate of firing--770 shots a minute--is at least three times as rapid as that of any other machine gun. It has only a single barrel, which, when the shot is fired, recoils a distance of three-quarters of an inch on the other parts of the gun. This recoil sets moving the machinery which automatically keeps up a continuous fire at the extraordinary rate of 12 rounds a second. Each recoil of the barrel has therefore to perform the necessary functions of extracting and ejecting the empty cartridge, or bringing up the next full one and placing it in its proper position in the barrel, of cocking the hammer, and pulling the trigger. As long as the firing continues, these functions are repeated round after round in succession. The barrel is provided with a water jacket, to prevent excessive heating; and is so mounted that it can be raised or lowered or set at any angle, or turned horizontally to the left or to the right. The bore is adapted to the present size of cartridges; and the maximum range is eighteen hundred yards. The gun can therefore be made to sweep a circle upwards of a mile in radius. Nor is the gun excessively heavy, its total weight being only one hundred and six pounds, made up thus: Tripod, fifty pounds; pivot (on which the gun turns and by which it is attached to the tripod), sixteen pounds; gun and firing mechanism, forty pounds. The parts can be easily detached and conveniently folded for carriage, and may be put together again so quickly that, if the belt containing the cartridges is in position, the first shot can be delivered within ten seconds. It would therefore be extremely serviceable in preventing disaster through a body of troops being surprised. Reconnoitring parties, too, would deem it prudent to pay greater deference to an enemy's lonely sentry on advanced outpost duty if the latter were provided with this new Machine Gun, instead of the ordinary rifle.