Changes

====Origins====

The almost intuitive design is known by many other names including the paternoster (after the beaded prayer chain it resembles), liberation or rope-and-washer pump. It is a relatively recent development of the ancient chain-and-washer pump. Evidence of the chain-and-washer pump dates back as far as two thousand years, to feudal China <ref> Fraenkel, Peter, and Thake, Jeremy. ''Water Lifting Devices, A handbook for users and choosers, 3rd ed.'' UK, Rugby: Intermediate Technology Publications Ltd, 2006.</ref>. The earliest report of the design in the west is cited <ref> Olsen, J. P. ''Greek & Roman Mechanical Water-Lifting Devices: The History of a Technology''. Toronto, Canada: University of Toronto Press, 1984. </ref> as that illustrated by the Sienese early renaissance engineer, Tacolla, circa 1433 <ref> Tacolla, Mariano. ''De Ingeineis'', Liber Primus Leonis, Liber Secundis Draconis, Addenda. c. 1433, folio 80. </ref>, a copy of which is given in the figure to the right <ref>Weisbaden, Ludwig, ed. et al. ''Facsimile of De Ingeineis'', Liber Primus Leonis, Liber Secundis Draconis, Addenda [online]. Germany: Satz Und Druck, 1984. Available at: http://digital.library.cornell.edu/k/kmoddl/pdf/037_001.pdf [April 2009]</ref>. In the 1970 and 80s the basic design was developed by numerous individuals, the most prominent of which were Alberts <ref>Alberts, J. H. The rope-pump - an example of technology transfer. ''Waterlines'', January 2004, Vol. 22 (3), 22-25.</ref>, Haemhouts <ref>Sandiford, Peter, et al. The Nicaraguan Rope-pump. ''Waterlines'', January 1993, Vol. 11 (3).</ref> <ref> Lammerink, M.P. et al. ''EVALUATION REPORT NICARAGUAN EXPERIENCES WITH ROPE PUMP'' The Netherlands: IRC, 1995. Available at: http://www.ropepumps.org/English/IRC-1995-Evaluation.pdf</ref> and Lambert <ref>Lambert, R. A. ''How to build a rope-and-washer pump''. London: Intermediate Technology Design Group, 1990.</ref>. and Thorpe. They applied the simple design as a tool aimed at economic and social development. They took advantage of low cost and versatile modern plastics to produce the modern rope-pump design.

[[Image:An illustration of the basic rope-pump design in the west circa 1433.jpg|thumb|right|200px|[[Rope pump| Rope Pump]] first illustrated in the west circa 1433 <ref>Weisbaden, Ludwig, ed. et al. Facsimile of De Ingeineis, Liber Primus Leonis, Liber Secundis Draconis, Addenda [online]. Germany: Satz Und Druck, 1984. Available at: http://digital.library.cornell.edu/k/kmoddl/pdf/037_001.pdf [April 2009]</ref>]]

==Suitable conditions ==

[[Image:RopePumpZambia.jpg|thumb|right|200px|[[Rope pump| Rope pump]] used for irrigation in Zambia]]

[[Image:Rope pump cross section.jpg|thumb|right|200px|[[Rope pump| Rope pump]] Cross section diagram of a rope pump on a capped well]]

Because of its low cost, the pump is also popular for domestic use. A survey among 5,025 rural families in Nicaragua indicates that a rope pump increases income, even if used for domestic purposes only. Families with a pump earn US$ 220 per year more than families without a pump. In Nicaragua the pumps are now being produced commercially by 20 workshops.