The earliest cannon of which we have any knowledge were clumsy contrivances, at first wider at the mouth than at the chamber, and made of wood, and later of iron bars, hooped together with iron rings, a system of the same type as that now in use in the wire-wound cannon. They at first seem to have fired balls of stone, iron balls coming later. A doubtful statement exists to the effect that cannon were used at the siege of Belgrade in 1073, and it is said that Edward III used them against the Scotch in 1327. Other dates of their use are 1338 and 1346, in which latter year Edward III employed them against the French at Crecy. For this we have the authority of Froissart. They were known under the varied names of bombards, serpentines, etc. Twelve cannon cast by Louis VII were named after the twelve peers of France, and Charles V gave twelve others the names of the twelve apostles. Other titles came later into general use, the royal or carthorne, carrying 48 pounds; the culverin, 18 pounds; the demi-culverin, 9 pounds; the basilisk, 48; the siren, 60, etc. In still later times cannon became known by the weight and the balls they carried, 6-pounders, 12-pounders, etc. But they are now usually called after the size of their bores, as 6-inch, 8-inch, or 12-inch cannon. The oldest example still in existence is “Mons Meg,” preserved at Edinburgh Castle. This is one of the iron-bar type, hooped by iron rings. It is supposed to have been used by James II of Scotland, at the siege of Threave Castle in 1455. [Illustration: THREE INCH NAVAL LANDING GUN, CARRIAGE AND LIMBER Weight of gun and mechanism, 675 pounds. Length of gun, 74.35 inches (25 calibers). Weight of projectile, 13 pounds. Travel of projectile in bore, 62.9 inches (20.97 calibers). Weight of charge, 18 ounces of smokeless powder. Muzzle velocity, 1,650-foot seconds. Muzzle energy, 246-foot tons. Weight of gun, carriage, limber, drag ropes, tools, etc., and 60 rounds of ammunition, complete, 3,420 pounds. The carriage and limber have each two removable interchangeable ammunition boxes for 12 rounds each, with a box for 12 rounds below the axle of the limber. _Courtesy of the Bethlehem Steel Co._]