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[[Image:arch screw icon.png|right|100px]]

[[Image:archimedes screw.jpg|thumb|right|250px|Farmers in Egypt's Nile delta turn a traditional (enclosed) screw by hand to irrigate a field. Photo: [http://www.waterencyclopedia.com/Po-Re/Pumps-Traditional.html#b Waterencyclopedia.com]]]

[[File:Archimedes-screw one-screw-threads with-ball 3D-view animated small.gif|thumb|250px|Archimedes' screw was operated by hand and could raise water efficiently. Animated GIF: [http://demonstrations.wolfram.com/ArchimedeanScrew/ Wolfram Demonstrations Project.]]]

[[Image:arch screw 2.jpg|thumb|right|250px|An Egyptian farmer turning an Archimedes screw by hand to irrigate a field. [https://www.cs.drexel.edu/~crorres/Archimedes/Screw/Applications.html Photo:] Helen and Frank Schreider of the National Geographic staff.]]

The Archimedes Screw (named after a Greek mathematician) is though to have been around since 250 B.C.E. However, archaeological evidence has led others to posit its earlier invention in Assyria (modern day Iraq) or Egypt; Archimedes simply improved upon an earlier design.<ref> [http://www.archimedeshydroscrew.com/archimedes-screw-pump/ The basic principle of an Archimedes screw pump]. Archimedeshydroscrew.com</ref>