According to Roman writers who chronicled the life of Archimedes, the mathematician was a devoted subject of Hiero ii, ruler of Syracuse, and spent part of his career designing and building weapons to defend Syracuse -- catapults, pulley hoists and levers for disabling enemy ships and siege towers. The ancient historians Polybius, Plutarch and Pliny the Elder all mention such inventions, although none was alive in Archimedes' lifetime. Some Greco-Roman historians also assert that during the Roman siege of Syracuse from 214 to 212 B.C., at the height of the Second Punic War, Archimedes used bronze mirrors to focus sunlight on Roman ships and set them on fire.