Sling (weapon)
Siege engines

The traction trebuchet was a siege engine which uses the power of men pulling on ropes or the energy stored in a raised weight to rotate what was, again, a staff sling. It was designed so that, when the throwing arm of the trebuchet had swung forward sufficiently, one end of the sling would automatically become detached and release the projectile. Some trebuchets were small and operated by a very small crew; however, unlike the onager, it was possible to build the trebuchet on a gigantic scale: such giants could hurl enormous rocks at huge ranges. Trebuchets are, in essence, mechanized slings.
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