Archimedes claw.

The Claw of Archimedes (also known as the "iron hand") was an ancient weapon devised by Archimedes to defend the seaward portion of Syracuse's city wall against amphibious assault. Although its exact nature is unclear, the accounts of ancient historians seem to describe it as a sort of crane equipped with a grappling hook that was able to lift attacking ships partly out of the water, then either cause the ship to capsize or suddenly drop it.

These machines featured prominently during the Second Punic War in 214 BC, when the Roman Republic attacked Syracuse with a fleet of 60 Quinqueremes underMarcus Claudius Marcellus. When the Roman fleet approached the city walls under cover of darkness, the machines were deployed, sinking many ships and throwing the attack into confusion. Historians such as Polybius and Livy attributed heavy Roman losses to these machines, together with catapults also devised by Archimedes.