Pump water using a regular garden swing.
This is a first proof of concept and it's a scale model; there's lots of room for improvement... pumping around 3 liters a minute at the moment.
For details of how to build this and to see more videos, see this Instructable
... the link is to a construction diary, step 10 - build a swing from bamboo - the earlier steps describe how to build the pump.
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