Leonardo da Vinci sketched a water screw as a hydraulic machine for raising water.
A water screw uses a helical surface inside a tube or around a shaft. When the screw rotates, water is carried upward from a lower level to a higher one. Leonardo studied screw-based water-raising mechanisms as part of his broader investigations into hydraulics, canals, mills, and irrigation.
The design is closely related to the Archimedes’ screw, which was known long before Leonardo. Therefore, Leonardo should not be credited with inventing the basic machine. His importance lies in observing, drawing, and adapting mechanical principles for Renaissance engineering problems.
Water screws remain useful where water must be lifted gradually and reliably. They are different from water wheels, which extract energy from moving water to turn a shaft; a water screw generally consumes rotational energy to move water uphill.