What rotating water-powered machine did Leonardo da Vinci design to drain marshes?

Leonardo da Vinci designed versions of the Archimedes’ screw for lifting and moving water.

An Archimedes’ screw consists of a spiral surface inside a tube or around a central shaft. When it rotates, water is carried upward along the spiral. Leonardo studied this principle as part of his extensive work on hydraulics and proposed applications including irrigation, drainage, and the reclamation of wet land.

Leonardo did not invent the basic machine: the device is traditionally associated with Archimedes of Syracuse, who lived in the third century BCE. Leonardo’s contribution was to analyze, draw, and adapt hydraulic machinery in detail. The screw should also not be confused with his aerial screw, which was a separate flying-machine concept.