CATAPULT, a generic name for warlike engines of the cross bow type used by the ancients (Lat. catapulta, Gr. Kara/Tarns). (See ENGINES OF WAR.) They are usually classed as (a) catapults and (b) ballistae (XtOof36Xoe) . The former were smaller and were used with arrows for what is now called direct fire (i.e., at low angles of elevation) ; the latter were large siege engines discharg ing heavy bolts or stones at a high angle of elevation, like the modern howitzer.
The essential parts of the catapult (see illustration) were the frame, the propelling gear, the trough (corresponding to the mod ern barrel) and the pedestal. The frame consisted of two hori zontal beams forming top and bottom sills, and four strong up right bars mortised into them. The three open spaces or compart ments resembling narrow windows, between these four uprights, carried the propelling and laying gear. The propelling gear occu pied the two outer "windows." In each a thick skein of cord or sinews was fastened to the top and bottom sills and tightly twisted.
The stiff wooden arms were inserted in the two skeins, and a spe cially strong bowstring joined the tips of these arms. In the mid dle compartment was the hinged fore-end of the trough, which was at right angles to the frame and at the back of it. The trough could be laid for elevation by a movable prop, the upper end of which was hinged to the trough, while the lower ran up and down a sort of trail fastened to the ped estal. The whole equipment was laid for "line" by turning the frame, and with it the trough, prop and trail by a pivot in the head of the pedestal. Sliding up and down in the trough was a block, fitted with a trigger mech? anism, through which passed the middle of the bowstring. The pedestal was a strong and solid upright resting upon, and strutted to, a framework on the ground; its upper end, as mentioned above, took the pivot of the frame and the head of the trail.
On coming into action the ma chine was laid for direction and elevation. The block and with it the bowstring was next forced back against the resistance of the twisted skeins to the rear end of the trough, this being effected by a windlass attachment. The trigger being then pressed or struck with a hammer, the bowstring was released from the block, the stiff arms were violently brought back to the frame by the untwisting of the skeins, and the arrow was propelled through the centre "window" with great velocity.
A small machine of the type described weighed about 85 lb., and sent a "three-span" (26in.) arrow weighing 2 lb. at an effective man-killing velocity somewhat over 400yds.
The ballista was considerably larger and more expensive than this. In Scipio's siege train, at the attack of New Carthage (Livy xxvi. 47, 5), the number of the ballistae was only one-sixth that of the catapults. In the ballista the rear end of the trough (which projected in front of the frame) always rested upon the ground, or rather was fixed to the framework of the pedestal—which was a heavy trestle construction—and the trough was thus restricted to the angle of elevation, giving the maximum range (45°). Even so, the range was not appreciably greater than that of a catapult, and in the case of the largest ballistae (90-pounder) it was much less. These enormous engines, which, once in position, could not be laid on any fresh target, were used for propelling beams and stones rather than for shooting arrows, that is, more for the de struction of material than for man-killing effect. The skeins that supplied the motive force of all these engines were made of the sinews of animals, twisted raw hide, horsehair rope, and, in at least one celebrated case, of women's hair. In 146 B.C., the au thorities of Carthage, having surrendered their engines to the Romans in the vain hope of staying their advance, new ones were hurriedly constructed, and the women and virgins of the city cut off their hair to supply the needed skeins.
The modern implement known as a "catapult" is formed by a forked stick, to the forks of which are attached the ends of a piece of elastic. To the middle of this elastic a pocket is fitted to con tain a bullet or small stone. In use the forked stick is held in the left hand and the pocket drawn back with the right. Aim is taken and, the pocket being released, the missile flies through the fork of the stick. Though classed as a toy, this weapon can do con siderable execution among birds, etc., when skilfully used. The name of "catapult" has also been given to a bowling machine which is used for cricket practice.