Page "Ballista" Paragraph 4

The early ballista in Ancient Rome was developed from two weapons called oxybeles and gastraphetes.

The gastraphetes (' belly-bow ') was a hand held crossbow.

It had a composite prod and was spanned by bracing the front end of the weapon against the ground while placing the end of a slider mechanism against the stomach.

The operator would then walk forward to arm the weapon while a ratchet prevented it from shooting during loading.

This produced a weapon which, it was claimed, could be operated by a person of average strength but which had a power that allowed it to be successfully used against armoured troops.

The oxybeles was a bigger and heavier construction employing a winch, and was mounted on a tripod.

It had a lower rate of fire and was used as a siege engine.