CANNON (Fr. canon, gun, from Med. Lat.
canon, tube, Lat. canna, reed; cmfused with Gk. tearer, /.•ann, straight rod, rule). Artillery weap ons not capable of being carried and tired in the hands, and from which projectiles are thrown by the expansive force of gases, produced by the emnbustion of an explosive. They are either smooth-hore or rifled. The former class of can non, which are now obsolete, were used to fire spherical projectiles, while from the latter oblong projectiles are discharged. Cannon may be divided into three classes: First, guns. or those cannon in which the length of the bore is relatively great in comparison to the calibre; second, mortars, or those cannon in which the length of the bore is relatively small in •ompari son with the calibre: third. howitzers, or those cannon whose relative length and calibre place them between the other two classes. They way also be classified according to their use into mountain artillery, tield artillery, siege a•til lery and seacoast or fortress artillery, a etas sitioation which will be observed in this work.
A further classification divides them into those in which the powder-charge is inclosed in a me tallic eartridge-case and those using a cartridge bag. The former group is subdivided into ma chine-guns, revolving cannon, and rapid-fire guns. As to construction, cannon are divided into those made of a single piece and those built up of t WO or more pieces, as is now usually the ease. Built-up cannon are either composed of steel forgings, having a tube CNtending through the length of the bore, with superposed concen tric hoops, or a tube With the remainder of the wall composed entirely or in part of a reetangu lar, circular, or ribbon form of wire. Service cannon in the United States, excepting machine gulls, are generally of the built up. forged-steel type. See OanxAxcE; Anrii.rmir COAST ARTIL