What water-engineering device did Leonardo da Vinci design to lift water continuously?

Leonardo da Vinci designed versions of Archimedes’ screw to lift water continuously.

An Archimedes’ screw uses a helical surface inside a cylinder or trough. As the screw rotates, water is carried upward along the helix. Leonardo studied and drew screw-based water-lifting machines, adapting the ancient principle for engineering applications.

The device was not Leonardo’s original invention. Ancient Greek tradition attributes the screw to Archimedes, who is traditionally associated with the 3rd century BCE. Leonardo’s contribution was his detailed Renaissance analysis and his exploration of mechanical arrangements that could drive such machines.

The screw differs from Leonardo’s aerial screw, which was a proposed flying machine. Both use a spiral form, but one moves water and the other was intended to create lift in air. Modern screw pumps still use the same basic principle.