The wheels and wheel fastenings are the same as, and interchangeable with those used on the carriage. Seats for three cannoneers are provided by a perforated metal bucket-holder on top of the chest. The paulin issued to each limber serves as a seat cushion and is held in place by paulin straps. Grip straps are also provided for use by the cannoneers when the carriage is moving at rapid gaits. On the sides and front of, and under the ammunition chest, suitable straps, brackets and connections are provided for securing all tools and accessories. With each limber are issued three tubular oil cans, each in the form of a cartridge and with a capacity of two-thirds of a gallon. These are intended to hold hydroline, lubricating and coal oil and are carried in the central row of cartridge holes in the ammunition chest. [Illustration: 3 INCH GUN CAISSON LIMBER, MODEL OF 1916 SIDE AND REAR VIEWS.] Weights and Dimensions. Weight of limber, completely equipped and loaded 1740 lbs. Weight of gun, carriage and limber, completely equipped and loaded 4260 lbs. Number of rounds carried 36 Nomenclature of important parts of limber:— Pole, complete, consisting of— Pole body Neck-yoke counter stop Neck-yoke stop Neck-yoke chafing plate Butt reinforce Doubletree Doubletree rods Name plate Limber prop Foot rest Tie-rods Pintle with bearing, consisting of— Pintle Pintle latch Pintle latch spring Wheels and wheel fastenings Axle Middle rail Side rails Ammunition chest, consisting of— Hand rail Door chains Shot bolts Bucket holder Chest rails Chest-rail connections Body Door Cartridge holes Diaphragms Lantern brackets Grip-straps Paulin straps Various tool brackets Various tools Paulins Picket ropes Lanterns Canvas buckets THE CAISSON The Caisson is made of metal throughout with the exception of the spokes and felloes of the wheels. The principal parts are the wheels, axle, pintle, lunette, apron shield, fuze setter bracket, frame, road brake, and ammunition chest. [Illustration: _Caisson, Plan_]