It was a launcher of small stones. The case (“syrinx”) was framed by two oblong boards which internally had iron ratchets. The sliding central beam (“slider”) was cocked with the help of ropes and a powerful manually-operated winch and secured in the prongs of ratchets. The slider, after the launch, moved forwards again (so as to accept the bow-string) with the help of a pull-back mechanism which functioned with the opposite rotation of the winch. The string had a leather sling and a metal ring that constituted the reception for the claw. The catapult was roughly 3 m long and launched spherical missiles of 10-12 cm in diameter and weighing 2 – 3 kg.
SOURCES: Biton, Construction of War Machines and Artillery.