Archimedes' screw screws of decreasing pitch are used for the compaction of waste material. If water is fed into the top of an Archimedes screw, it will force the screw to rotate. The rotating shaft can then be used to drive an electric generator. Such an installation has the same benefits as using the screw for pumping: the ability to handle very dirty water and widely varying rates of flow at high efficiency. Settle Hydro and Torrs Hydro are two reverse screw micro hydro schemes operating in England. The screw works well as a generator at low heads, commonly found in English
SS Archimedes overhaul. Her engines and machinery were removed on an unspecified date at Sunderland, after which she continued in service as a sailing ship. In 1852, her sails and rigging were renewed, but she disappeared from the Register again a year or two later. She reportedly ended her career in the 1850s, in service between Chile and Australia. Although the adoption of the screw propeller was an historical inevitability given the work of John Ericsson and others, "Archimedes" considerably hastened acceptance of the technology. The Dover trials, carried out in April–May 1840, persuaded the Royal Navy to build a 900-ton steam