The Crossbow or Arbalest is first heard of in the twelfth century, and at this date was considered so 'unfair' a weapon that the Popes forbade its use. Innocent II in 1139 fulminated against this barbarous weapon, but allowed of its use by Christians against Infidels. By the end of the thirteenth century, however, it was in general use. At first the crossbow was strung by hand; but when it was made more powerful, mechanical means had to be resorted to to bend the bow, which was often of steel. There are two varieties of war crossbows: that strung with the 'goat's-foot' lever, which is shown on Fig. 51, and a heavier kind called the arbalest '_à tour_', which was strung with a cog-wheel and ratchet arrangement called the Moulinet or windlass (Fig. 52). The arbalest '_à cric_' is a larger form of this variety. The archer using these heavy weapons was entrenched behind a Pavis or shield fixed in the ground as shown on Fig. 37. The Quarel or bolt used for the crossbow is shorter and thicker than that used for the longbow. [Illustration: FIG. 51. Crossbow and goat's-foot lever.] [Illustration: FIG. 52. Crossbow and windlass.] Of the other projectile-hurling weapons, such as the Fustibal or Sling, the different forms of Catapult used in siege operations, and the innumerable varieties of firearm, we have no space to write. The former, being mostly fashioned of wood and cordage, are seldom to be met with in museums, and we can only judge of their design and use from illuminated miniatures and paintings. The firearm, being, as it is, subject to further development, cannot be taken into full consideration in this work except so far as it affected the defensive armour and in time ousted the staff-weapon.