What Leonardo da Vinci machine used a screw conveyor to move water upward?

Leonardo da Vinci studied and designed versions of Archimedes' screw for moving water upward.

An Archimedes' screw is a helical surface wrapped around a central shaft inside a tube or trough. When the screw rotates, pockets of water are carried upward along the helix. The device can lift water for irrigation, drainage, fountains, and other hydraulic work.

The invention is named after Archimedes, who is traditionally credited with developing the mechanism in ancient Syracuse. Leonardo did not invent the original screw, but his notebooks contain careful studies of screw geometry and water-moving machines.

This distinction matters because Leonardo is often credited too broadly for devices he redesigned or analyzed. His contribution was frequently the refinement and visualization of existing mechanical principles. His interest in hydraulic engineering included canals, locks, pumps, and methods for controlling water flow.