=Arm-rack.= A frame or fitting for the stowage of arms (usually vertical) out of harm’s way, but in readiness for immediate use. In the conveyance of troops by sea arm-racks form a part of the proper accommodation. Arm-racks are also used in soldiers’ barrack-rooms. =Arms.= In a general sense, comprehend weapons both of an offensive and defensive character, but in the usual restricted sense they only embrace the former, and in modern warfare include the gun and bayonet, the rifle, the pistol, the carbine, the sword, the lance, cannon, etc., all of which are noticed under their respective heads. For punishment inflicted upon soldiers who sell or otherwise dispose of their arms, see APPENDIX, ARTICLES OF WAR, 17. =Arms.= This term is used in heraldry to designate the devices borne on shields, and includes all the accompaniments, such as the crest, helmet, supporters, etc. =Arms, Bells of.= Are tents, used in the English service, mostly of a conical shape, for containing the small-arms for each company in a regiment of infantry. The tent is frequently painted with the color of the facings of the regimental uniforms. =Arms, Stand of.= A complete set for one soldier, as a rifle and bayonet, cartridge-box and belt, frequently the rifle and bayonet alone. =Armstrong Gun.= The Armstrong gun as a breech-loading field-piece first attracted attention in England about 1850. About 1858 it was adopted by the British government. This gun was made of wrought iron, and consisted of a single coiled tube reinforced at the breech with two thin tubes, the outer one being a coiled tube, the inner being formed by bending a plate and welding the edges. The coiled tubes were formed by bending square bars of iron around a mandrel and welding the coils together. Tubes made in this way offer great resistance to tangential strains. The intermediate tube was designed to take up the longitudinal strain near the breech, and for this reason was made differently. The breech was closed with a vent-piece, slipped by the band into a slot cut in the piece near the breech, and held in its place by a breech-screw, which supported it from behind. This screw was made in the form of a tube, so that its hollow formed a part of the bore prolonged, when the vent-piece was drawn. Through the hollow screw the charge was passed into the chamber. The vent was formed in the breech-piece. This gun was a 3-inch 12-pounder, firing a lead-coated projectile. It was followed by the 40-pounder, 110-pounder, and other calibres. Muzzle-loaders were also made. The breech-loading apparatus did not prove entirely successful in large guns, and was accordingly discarded except for small calibres. The method of construction was changed for larger guns, and a plan adopted which has been adhered to ever since, and is that now used. The barrel or part surrounding the bore is made of steel tempered in oil; that portion at and in rear of the trunnions is enveloped by several layers