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HISTORY AND CONSTRUCTION] introduced. They must have gradually appeared as a means of surmounting the difficulties engendered by the recoil of the piece and of transport of the early guns and their cradles. Andrea Redusio mentions in Chronicon Tarvisinum the use of two wheeled bombard carriages at the siege of Quero by the Venetians in 1376. It does not follow that these weapons were of large dimensions, as the term “bombard” was applied to small guns as well as to the more ponderous types.

The ancient carriages used on land are remarkable from the fact that in general design they contain the main principles which have been included in field carriages up to the present day. Until 1870 the body of all field carriages was made of wood. In an early type the trail portion was made of a solid baulk of timber supported at the front by a hard wood axletree, on the arms of which the wheels were placed (iron axletrees were introduced by Gribeauval in 1765). The gun resting in its wooden cradle was carried in bearings on the trail immediately over the axletree (fig. 4), the cradle being provided with an axle or trunnions for the purpose. For giving elevation a wood arc was fixed to the trail towards the rear end, and the breech end could be moved up and down along this arc and fixed at certain positions by a pin passing through both cradle and arc. About the middle of the 15th century the trunnions were formed with the gun—the wood cradle therefore became unnecessary and was discarded. The carriage was then formed of two strong cheeks or sides of wood fastened together by four wood transoms. At the front end the cheeks were secured to the wooden axletree, which was strengthened by a bar of iron let into its under side. Trunnion bearings were cut in the upper surface of the cheeks over the axletree, and these were lined with iron, while the trunnions were secured in position by iron cap-squares. Elevation was given by a wedge or “quoin” being placed under the breech and supported by a transom or stool bed. For transport the trail end of the carriage was supported on a limber, a pintle on the limber body passing through a hole in the trail. One set of shafts were fixed to the limber, and a single horse was harnessed to them; the remainder of the team were attached in pairs in front. A driver was provided for every two pairs of horses. In Italy oxen were often yoked to the larger guns instead of horses. Tartaglia mentions in his Nova scientia (1562) that 28 oxen were required for a gun 15 ft. in length and weighing ; horses were used for small guns only.

For service on board ship the difficulties of the cramped situation seem to have been surmounted in an ingenious manner. In the “Mary Rose,” sunk in the reign of Henry VIII., the brass guns with trunnions were mounted on short wood carriages provided with four small wood wheels called “trucks” and fastened to the gun ports by rope breechings. The iron breech-loading guns were employed in restricted positions where loading at the muzzle would be difficult. They had no trunnions and were mounted in a wood cradle, the under side of which was grooved to enable it to slide on a directing bar.

At the end of the 17th century not much progress had been made. The larger guns were mounted on short wood carriages having two or four “trucks.” The guns and carriages recoiled along the vessel’s deck, and where this endangered the masts or other structures the recoil was hindered by soft substances being laid down in the path of the recoil.

The small guns were mounted in iron Y pieces—the upper arms being provided with bearings for the gun trunnions—and the stalk formed a pivot which rested in a socket in the vessel’s side or on a wall, so that the gun could be turned to any quarter.

Similar carriages (fig. 5) existed until the advent of rifled guns, but a few small improvements, such as screw elevating gear in place of the quoin, had been approved. Cast iron standing carriages were also, about 1825, used on land for hot climates and situations not much exposed.

The earliest guns were not provided with sights or other means for directing them. This was not important, as the range seldom exceeded 100 yds. As, however, ranges became longer, some means became necessary for giving the correct line and elevation (see also ). The direction for line was easily obtained by looking over the gun and moving the carriage trail to the right or left as was necessary. For elevation an instrument invented by Tartaglia called a Gunner’s Quadrant (sometimes also called a Gunner’s Square) was used; this was a graduated quadrant of a circle (fig. 6) connecting a long and short arm forming a right angle; a line with a plummet hung from the angle in such a manner that on the long arm being placed along the bore near the muzzle the plummet hung down against the quadrant and indicated the degrees of elevation given to the piece. The quadrant was divided into 90° and also into 12 parts; it was continued past the short arm for some degrees to enable depression to be given to the gun. The instrument was also used for surveying in obtaining the heights of buildings, and is still much employed for elevating guns in its clinometer form, in which a level takes the place of the plummet.

For short range firing a dispart sight was in use early in the 17th century. A notch was cut on the top of the breech or base ring, and on the muzzle ring a notched fore sight (called the dispart sight) was placed in the same vertical plane as the notch, and of such a height that a line stretched from the top of the breech ring notch to the notch of the foresight was parallel to the axis of the bore. These sights were well enough for close, horizontal fire and so long as the enemy were within what was called “point blank” range; that is the range to the first graze, on a horizontal plane, of the shot when fired from a gun the axis of which is horizontal. As this range depends entirely, other things being equal, on the height of the gun’s axis above the horizontal plane, it is not very definite. When, however, the enemy were at a greater distance, elevation had to be given to the gun and, as a quadrant was slow and not easy to use, there was introduced an instrument, called a Gunner’s Rule (see The Art of Gunnery, by Nathanael Nye, 1670), which was really a primitive form of tangent sight. This was a flat brass