A missive weapon discharged by the force of ignited powder from a fire-arm in warfare: of these there are various kinds, as round shot, or bullets, a ball or sphere of iron whose weight is in proportion to the bore of the cannon. Double-headed, or bar-shot, are formed of a bar of iron with a ball at each end, which fits the muzzle of the cannon. The middle is sometimes filled with composition, and the whole covered with linen dipped in brimstone; so that the cannon, in firing, it is said, thus inflames the combustibles or composition, which sets fire to the sails of the enemy. One of the beads of this ball has a hole to receive a fusee, which, communicating with the charge of the cannon, sets fire to the bullet.
Chain shot consist of two balls chained together, being principally designed to annoy the enemy by cutting her sails, rigging, etc. Grape shot is a combination of balls strongly corded in canvass upon an iron bottom, so as to form a cylindrical figure, whose diameter is equal to that of a ball which is adapted to the cannon. Case shot, or cannister shot, are composed of a great number of small bullets, put into a cylindrical tin box. They are principally used when very near, to clear the decks of the enemy. Besides these, there are others of a more pernicious kind, such as langrage shot, star shot, fire arrows, etc, employed also when not at a great distance from the enemy.
Cannon shot that are cast in moulds, usually possess, in a greater or less degree, the three following defects: - first, being imperfect in their spherical figures, which is owing to the expansion and alteration of form made in the moulds, from frequently heating them; second, containing air cavities, owing to the air being caught in the moulds when the fluid metal runs in too quickly for it to escape; third, their having usually an indentation where the metal is poured in. To obviate these defects, Mr. Booth by, of Chesterfield Iron Works, manufactures his cannon balls in the following manner, for which he has taken out a patent. A solid ball of hard wood or metal is turned to a true sphere (according to the size or weight of shot required), and then cut in halves. These halves are moulded in sand boxes, in the usual manner of other castings, taking care that the sand be well rammed; then taken out, and the hollow moulds thinly coated with powdered charcoal mixed with water. The boxes containing the moulds are next dried in the stove, preparatory to receiving the fluid metal.
The shot thus cast are said to be perfectly sound and spherical, owing to the air escaping through the sand, and the mould being unaltered in its figure by heating.