The _front sight_ is of the open type, allowing of a large field of view. The _tangent-sight_ is provided with a sliding head by means of which it may be set before placing it on the gun, and a deflection-slide for correcting for drift, wind, etc. On the deflection-slide is an open notch for rough, and a peep-sight for fine, sighting. The sight-bar is graduated on one side in ranges, on the other in millimetres. The sights are on the left side. THE CARRIAGE. [Illustration: Fig. 14.] NOMENCLATURE.--(1) trail; (2) axle; (3) wheel; (4) cap-squares; (5) hooks; (6) elevating-screw; (7) elevating-lever; (8) elevating-transom; (9) lunette; (10) lunette-plate; (11) trail-handles; (12) brakes; (13) sponge and rod. DESCRIPTION. Length of carriage-body 52.75 inches Weight of carriage-body 205 pounds Weight of sponge and rod 4.5 " Weight of two wheels 123 " Total weight of carriage 332 " Height of trunnion-centres above ground 23.7 inches Diameter of wheels 37.4 " Track of carriage 28.35 " Vertical field of fire +20°, -10° Total weight of gun and carriage 570 pounds The carriage-body consists of two steel brackets forming stock and trail. They are reinforced by angle-steel and connected by transoms. The axle is stiffened by a reinforcing-plate to which is riveted the carriage-body. The elevating-gear consists of a forked lever, pivoted at its nearmost end, and traversed near the middle by the elevating-screw. The latter is supported by an inclined plane on the elevating-transom. The breech of the gun rests freely on the end of the elevating-lever, the preponderance being sufficient to insure stability. Recoil is checked by two rope-brakes, which are hooked to the trail-handles and passed around the felloes of the wheels. For the march one end of each brake is hooked to a trail-handle, the rope passed diagonally over the trail end and the free end secured to one of the hooks under the axle. The sponge and rod are secured by suitable attachments on the right side of the trail. THE PRAIRIE LIMBER. [Illustration: Fig. 15.] NOMENCLATURE.--(1) axle; (2) axle-beds; (3) frame; (4) body; (5) pintle; (6) pintle-key; (7) shafts; (8) prop; (9) prolonge-hooks; (10) ammunition-chests. DESCRIPTION.