Maurice, about 1600, did away with the great variety of guns which existed, and retained four different calibres only, so as to facilitate the supply of shot. Gustavus, a little later, introduced lighter guns, and cartridges for the powder, which till then had been carried loose in barrels. But his main innovation was the allotment of two light guns to each Infantry Battalion, for action in the intervals between Regiments, an organization retained in most armies till the end of the eighteenth century. These “Battalion guns” were drawn by one or two horses, or by men when under fire, and were often served by the Infantry they were attached to. He used the heavier guns in masses on the wings and in the centre; but no Battery organization came in till late in the eighteenth century. In France, under Louis XIV., the step was taken of creating a Regiment of Artillery, formed of Gunners and Artificers, the Drivers being still hired. This idea was partially copied in England, where the Artillery was organized into a Military Corps in 1716. Other armies formed Companies of Artillery, but had no Regimental organization till much later. Shells were first used in the field about 1700, they fired from what were called _Hautbitzers_, now _Howitzers_, a Czech word taken from Zisca’s organization of the Hussite hosts in Bohemia long before. Grapeshot was also invented; but solid shot was the projectile of Artillery down to the introduction of General Shrapnel’s shell in the British Artillery about 1810, followed much later by the universal adoption of shell fire for field guns. Another invention, Congreve’s rocket, was partially adopted in the English service before the battle of Waterloo.