Two ancient and preventable practices seem to have operated in chief measure to retard the progressive development of a mobile land artillery: first, the custom of setting the trunnions of a gun at an appreciable distance below the horizontal plane of the gun-axis; second, the custom of making small pieces relatively longer than those of larger calibre. [Illustration: From Binning’s _A Light to the Art of Gunnery_, A.D. 1689] The first guns had no trunnions. To obtain the requisite angle of elevation the piece was laid in a dug-out trunk or carriage and this carriage was set on trestles; in which manner, it appears, the English at the siege of Orleans in A.D. 1428 “threw into the town from their bombards large numbers of stones which, flying over the walls, smashed in the roofs of houses.”[65] During the fifteenth century trunnions came into use, and the carriages were mounted on wheels. In his _Introduction of Artillery into Switzerland_ a French writer, Colonel Massé, has given an account of the early evolution of an artillery of position, as used by the Swiss and their enemies in the fifteenth century. The huge siege bombards, possessed by most of the great cities at the end of the fourteenth century, were too cumbrous for transport. Built up of welded and coiled iron, and therefore without trunnions, they were replaced, toward A.D. 1443, by lighter pieces on wheeled carriages. And before the Burgundian War “coulevrines de campagne” were being cast in Switzerland, of bronze, with trunnions to give each piece an elevation independently of its carriage. Relics are still preserved which show the gun-trunnion in its early stages, as embodied in the Burgundian artillery of Charles the Bold. The first method of obtaining elevation for the gun was by hinges or trunnions on the front of the carriage or trunk, in combination with a curved rack erected on the trail for supporting the rear end. Then the trunk disappeared; the trunnions were cast on the gun, whose cascabel was supported by a cross-pin between the flanks of the trail; and then the cross-pin was made removable, and a series of holes was provided for its reception, to give the elevation desired. At first these trunnions were cast level with the gun axis; in Napoleon III’s treatise on artillery is a picture of a trunnion gun taken by the Swiss from Charles the Bold in 1476, and another of a cannon of Louis XI, cast in 1478, and in both cases the trunnions are level with the gun axis. But pieces cast later almost invariably had their trunnions set on a level with the bottom of the bore; partly, perhaps, for the insignificant reason given by Norton--that “lying somewhat under the concave cylinder of the bore they will the better support the great weight”--but primarily to ensure a downward pressure on the quoin or trail when discharge took place. The effect of this trivial alteration was enormous. The impulse of the recoil was given a moment about the