ORDNANCE, a general term applied to the great artillery (guns, carronades, howitzers, and mortars) which is used in war, on land or at sea ; the name being probably derived from the compagnies d'ordon nance, or Francs Archers, instituted in 1448 by Charles VII. of France.
The wars between the emperor Charles V. and Francis I. gave rise on the Continent to the first important improvements in the con struction and use of heavy artillery. According to Templehof it was then that some efforts were made to establish a system of proportions between the length, the thickness, and the calibre of ordnance ; that gunpowder was improved, and that certain relations between the charge of powder and the weight of the projectile began to be established. It was not, however, till the beginning of the 17th century that artillery, which had before been chiefly used in the attack and defence of fortresses, began to be extensively employed in engagements between hostile armies; but in 1632 the Austrians and Swedes together are said to have brought into the field 2000 pieces, among which were 24, 16, 12, and 6 pounder guns.
An artillery capable of accompanying the rapid movements of cavalry, was first systemically introduced into warfare by Frederic the Great [ARTILLERY] ; but the full development of the important services which are capable of being rendered by this an is due to the Prussian general Scharnhost, since whose time the horse-artillery, as it is called, has been considered as an indispensable requisite in the armies of every nation in Europe.
In the British service a rocket carriage and tube for the military rockets invented by Sir W. Congreve, is attached to each troop of horse artillery and battery of artillery ; and these missiles, which have been employed under various circumstances, have occasionally rendered con siderable service. [Rocesv.] The construction or mode of manufacture of artillery has been described under CANNON. Under the present head we propose to describe generally the size, &o., of the guns now in use in the
service, and very briefly their uses. Rifled ordnance, which are now being adopted in the service, will be found described under RIFLE.
Under the general term ordnance there were comprised guns of five classes : shot guns, shell guns, howitzers, carronades, mortars ; to these may now be added the rifled ordnance, shot and shell guns.
Shot guns of the ordinary smooth-bored construction are com paratively long and heavy, being employed for projecting solid shot on all occasions when considerable penetration or length of range is requi site; they are of course, however, capable of throwing shells and all other descriptions of ammunition. The calibre of a shot gun is denoted by the weight of a cast-iron spherical shot, of which the diameter is the same with the hors of the gun. The heavy-shot guns are constructed of cast-iron, and are used for sea-coast batteries, for the armament of ships of war, for the defence of fortresses, for breaching, and for guns of position. Light-shot guns are constructed of bronze (they are generally called brass guns), and are employed only as field artillery in the English service. They are, however, employed for siege purposes by the French. The annexed diagram represents a brass gun (a heavy six-pounder). Shell guns. differ from shot guns in being of greater calibre in proportion to their weight of metal. The bore of shell guns is also contracted towards the breech, thus forming a chamber. The size of shell guns is denoted by the diameter of the byre in inches. Shell guns are employed for projecting shell and hollow shot, and are principally for sea service. They are made of Iron. Gums of 12-inch diameter have been made, but the sizes employed in the service now are the 10-inch and 8-inch guns only.
We have subjoined a table of the dimensions and weights of the principal natures of guns in use in the British service. The natures and uses of carnmules, howitzers, and mortars have been already described under those words.