Cannons, not mirrors: Archimedes legend revised

Debunking a legend begun in the Middle Ages, new research suggests Archimedes used steam cannons to set fire to Roman warships. The legend claimed that during the siege of Syracuse, mirrors were used to create a deadly concentration of sunlight that set the ships aflame.

Steam cannons similar to the design drawn by Leonardo da Vinci, which he credited to Archimedes, could have thrown a 13-pound cannonball at a speed of 60 feet per second. Hollow clay cannonballs filled with "Greek fire" or another incendiary chemical would start fires more effectively than a beam of reflected sunlight.