What simple machine did Leonardo da Vinci study and improve for lifting water?

Leonardo da Vinci studied and improved the Archimedes’ screw for lifting water.

An Archimedes’ screw is a helical surface wrapped around a central shaft inside a tube or trough. When the screw turns, pockets of water move upward along the spiral. Leonardo examined the device in his studies of hydraulics and proposed refinements to its shape and operation.

The machine is much older than Leonardo. It is traditionally associated with Archimedes of Syracuse, who lived in the third century BCE, although similar screw-based water-lifting devices may have developed through earlier engineering traditions. Leonardo’s contribution was Renaissance analysis and redesign rather than invention of the basic principle.

This water-lifting screw is distinct from Leonardo’s aerial screw. The aerial design used a helical surface intended to push against air, while the Archimedean device moves water. The shared spiral form can cause confusion, but their purposes and working environments are different.