Portal:Physics/Selected picture/April 2011

The Archimedes Screw
The Archimedes screw can raise water efficiently.

A large part of Archimedes' work in engineering arose from fulfilling the needs of his home city of Syracuse. The Greek writer Athenaeus of Naucratis described how King Hieron II of Syracuse commissioned Archimedes to design a huge ship, the Syracusia, which could be used for luxury travel, carrying supplies, and as a naval warship. The Syracusia is said to have been the largest ship built in classical antiquity. Since a ship of this size would leak a considerable amount of water through the hull, the Archimedes Screw was purportedly developed in order to remove the bilge water. Archimedes' machine was a device with a revolving screw shaped blade inside a cylinder. It was turned by hand, and could also be used to transfer water from a low-lying body of water into irrigation canals. The Archimedes screw is still in use today for pumping liquids and granulated solids such as coal and grain.