The Claw of Archimedes

Archimedes of Syracuse(c. 287 BC – c. 212 BC) was a Greek mathematician, physicist, engineer, inventor, and astronomer. Archimedes is generally considered to be the greatest mathematician and inventor of antiquity and one of the greatest of all time.

The Claw of Archimedes was an ancient weapon devised by Archimedes to defend the seaward portion of Syracuse's city wall against amphibious assault. Also known as "the ship shaker", the claw consisted of a crane-like arm from which a large metal grappling hook was suspended. When the claw was dropped on to an attacking ship the arm would swing upwards. The Claw of Archimedes 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 at least 120 Quinqueremes under Marcus 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, mechanical devices used to throw a projectile a great distance, also devised by Archimedes.

The plausibility of this invention was tested in 1999 by the BBC in their Secrets of the Ancients and then again in early 2005 by the Discovery Channel in their television show Superweapons of the Ancient World by bringing together a group of engineers to try to conceive of, design and implement a design that was realistic given what we know about Archimedes. Within seven days they were able to test their creation. They did indeed succeed in tipping a model of a Roman ship over so that it would sink.