Iron Field-Carriage.
This carriage consists of two ¼-inch plate-iron brackets recessed to receive the axle-tree. These plates are strengthened by angle-irons riveted along the upper edge on the outer side from the trunnion-holes to the point. The brackets are lightened as much as possible by having pieces cut out of them. A front transom of plate-iron, having angle-irons riveted to it each side to connect it with the brackets; a similar transom about half way down the brackets; an iron trail-plate and axle-tree, and wooden wheels. The carriage makes a load for a mule, and the wheels another load. The elevating-gear consists of an iron stool-bed formed in front to hook loosely over a cross-bar, while the rear end, provided with two small studs, rests in racks riveted to the brackets. This is for getting rapid elevations. For fine sighting a sliding quoin is fitted to the stool-bed by clips, and is worked by a hand-wheel. Check-ropes are applied to the trail-eye and lashed to the wheels in firing. The Gatling gun is provided with a curved ratchet projecting down from the bottom of the gun-case, giving elevations by means of a hand-wheel and pinion.
7-pdr. Field-Carriage.
Iron Boat-Carriage.
9-pdr. Boat-Carriage.
The boat-carriage is made up of two ⅝-inch plate brackets, having narrow stiffening pieces along the front and upper edges. The brackets are riveted to a bottom plate by angle-irons on the outer sides, and are connected in front by a transom of plate riveted to angle-irons, and in rear by another transom. It has two outside holding-down clips on each side. The elevating-screw admits of 10° elevation and 2° depression. The slide consists of two sides of girder-iron, 6½ inches deep, and are joined by a connecting plate, three bottom plates, and a rear transom. These bottom plates have metal friction-plates attached beneath them. The centre as well as the front is fitted with a pivot-bolt. The transporting axle bolts beneath the slide. The hydraulic buffer lies upon the centre and rear transoms, to each of which it is secured by a band. This buffer is nothing more than the ordinary type of long cylinder and piston.[3] The cylinder is nearly filled with oil through a hole in the upper rear part. In case it is desired to empty the cylinder, there is a hole for the purpose in the lower forward end. Holes of a certain diameter are bored through the piston, and the recoil is checked in proportion to the resistance of the oil in passing through these holes. The cylinder not being quite full leaves an air-cushion to ease the strain. The piston-rod is secured to the carriage, and a slight vertical play is allowed in its fastenings to prevent the jump of the gun from bending it.
Carriage for Light Upper-Deck Guns.
