It was a launcher of small stones. The case (“syrinx”) was framed by two oblong boards that internally had iron ratchets. The sliding central beam (“slider”) was cocked with the help of ropes and a powerful manuallyoperated winch and secured in the prongs of the ratchets. The slider, after the launch, moved forwards again (so as to accept the bow-string again) with the help of a small rotating axle (with hand levers). The string was divided into two parts that were linked with a leather sling and a metal ring that constituted the reception for the claw. The catapult was roughly 4 m long and launched spherical missiles of 20 – 25 cm in diameter and weighing15 – 20 kg.