Recorded and preserved on bamboo strips, much of the text is now unfortunately extremely corrupted. Much of what we now know of the siege technology of the time came to us from Books 14 and 15 (Chapters 52 to 71) on Siege Warfare from the Mo Jing. The earliest documented occurrence of ancient siege-artillery pieces in China was the levered principled traction catapult and an 8-foot-high siege crossbow from the Mozi (Mo Jing), a Mohist text written at about the 4th â 3rd century BC by followers of Mozi who founded the Mohist school of thought during the late Spring and Autumn period and the early Warring States period. Other weapons dropped heavy weights on opposing soldiers. Other hinged engines were used to catch enemy equipment or even opposing soldiers with opposable appendices which are probably ancestors to the Romancorvus. They were normally mounted on two or more ships tied together and some sambykÄ included shields at the top to protect the climbers from arrows. These were giant ladders, hinged and mounted on a base mechanism and used for transferring marines onto the sea walls of coastal towns.

For sea sieges or battles, seesaw-like machines ( sambykÄ or sambuca) were used. The most utilized engines were simple battering rams, or tortoises, propelled in several ingenious ways that allowed the attackers to reach the walls or ditches with a certain degree of safety. Their large engines spurred an evolution that led to impressive machines, like the Demetrius Poliorcetes' Helepolis (or 'Taker of Cities') of 304 BC: nine stories high and plated with iron, it stood 40 m (132 ft) tall and 21 m (69 ft) wide, weighing 180 t (360,000 lb). The first two rulers to make use of siege engines to a large extent were Philip II of Macedonia and Alexander the Great.

Siege engine models plans