The feed-trough holds about eight cartridges. The =Rear Sight= consists of a bar having its right edge arranged with alternate notches and points for each 100 yards or other unit. These notches and points are so arranged as to allow for the natural drift of the projectile. The bar is hinged at the bottom to lie flat on the breech-piece when not in use. The =Front Sight= is of the ordinary steel-point pattern. THE ACTION OF THE MECHANISM. Suppose the crank to be in continual motion. A cartridge is placed in the introduction-trough, the piston pushes it into the barrel, the barrels begin to revolve, and the cartridge is carried on until it arrives before the firing-pin, held in the solid part of the breech, and which has, in the meantime, been retracted by the action of the cam. As soon as the cartridge has arrived in position the barrels cease to revolve and the primer of the cartridge is struck by the firing-pin and discharged; the revolution of the barrels begins again, and the fired cartridge-shell is carried on until it comes to the extractor, which in the meantime has arrived up to the barrels, and the cartridge-head rolls into it. As soon as the head is laid hold of by the extractor the barrels again cease to revolve, and during this period the cartridge-shell is withdrawn and dropped to the ground. During every stoppage of the barrels the gun is supplied with a new cartridge, the firing and extraction are also performed, and a continuous but slow fire is kept up. Supplying the gun in this manner with single cartridges, about thirty rounds per minute may be fired. DISMOUNTING AND MOUNTING THE MECHANISM. =To Dismount.=--1. Open the breech-door by unscrewing the door-bolt. As the mainspring presses against the door, one hand should be pressed against the door to keep it from flying open. 2. Withdraw the firing-bolt by pulling straight out. 3. Detach the mainspring by first turning it completely over and then withdrawing its keep-pin. 4. Take out the thumb-screw which secures the extractor-crank to the worm-axle. 5. Withdraw the worm-axle by pulling straight out on the crank; and as the extractor-crank and worm-wheel slip off, remove them. 6. Pull out the extractor. 7. Pull out the loading-piston. 8. Unscrew the keep-pin of the cog-wheel and take the latter out. This completes the dismounting of the mechanism. =To Mount.=--Proceed in the inverse order, bearing in mind that in inserting the loading-piston it must be pushed in to its extreme forward limit, as marked by arrows on its forward end and on the rim of the feeding-hole, before the extractor is inserted. Also, in inserting the worm-axle the most convenient position is with the feather up, so that the extractor-crank will mount when it is turned arm down and to the rear. This is not necessary, but is convenient in assembling.