Screw turbine connected to a generator through a gearbox. The Archimedean screw is an ancient invention, attributed to Archimedes of Syracuse (287–212 BC.), and commonly used to raise water from a watercourse for irrigation purposes. In 1819 the French engineer Claude Louis Marie Henri Navier (1785–1836) suggested using the Archimedean screw as a type of water wheel. In 1916 William Moerscher applied for a U.S. patent on the hydrodynamic screw turbine. The Archimedean screw turbine is applied on rivers with a relatively low head (from 1 m to 10 m) and on low flows (0.01 m³/s up to around 10 m³/s on
Acorn Archimedes computers or IBM compatible PCs eclipsed the Archimedes in their multimedia capabilities, which led to an erosion of the Archimedes market share. The Tesco Computers for Schools scheme later changed partnership from Acorn to RM plc and many other computer-related suppliers, which also led to the decrease of the Archimedes' educational market share. Acorn Archimedes The Acorn Archimedes is a family of personal computers designed by Acorn Computers Ltd in Cambridge (England) and sold in the late-1980s to mid-1990s, Acorn's first general-purpose home computer based on its own ARM architecture. The first Archimedes was launched in 1987. ARM's RISC design,