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The treadle pump is based on a design developed in the 1970s by Norwegian engineer Gunnar Barnes.It can be made locally.
The treadle pump is easy to build from bamboo or other wood and has two metal cylinders (圆筒) with pistons (活塞).The pistons go up and down as a person stands on lever devices—treadles,and uses a natural walking motion.
How many hours a day the pump needs to be operated depends on the season and how much water is needed for crops.It could be two hours a day.It could be seven hours a day.
Small children sometimes stand with their parents on the treadles.Everyone in the family can take turns operating the pump.
The Acumen Fund is a nonprofit group that invests in business projects to fight poverty.It studied the effects of treadle pumps in the Indian state of Uttar Pradesh.Uttar Pradesh has three treadle pump manufacturers and more than seventy-three thousand pumps.
Acumen reported that families using them ate more vegetables,because they were able to grow more to eat and to sell.Many of these families also drank more milk,because they bought a cow with their added earnings.Men with treadle pumps often no longer have to leave the farm to seek extra work in cities.
The pump can also improve education.Farmers often use their extra earnings to buy books for their children or to pay for schooling.
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