What lifting device did Leonardo da Vinci design using a large screw?

Leonardo da Vinci designed a screw jack for lifting heavy loads.

The concept used the mechanical advantage of a screw: turning a handle moves a load-bearing part gradually upward while multiplying the operator’s force. Leonardo’s notebooks contain designs for lifting mechanisms that apply this principle to engineering and construction.

Screw mechanisms were already known before Leonardo, so he did not invent the screw itself. His contribution was to study and refine mechanical arrangements that could make lifting more controlled and practical.

A screw jack differs from a pulley crane because the load is raised by the motion of a threaded screw rather than by a rope running over a wheel. Modern vehicle jacks still use the same basic principle, although they are manufactured with far greater precision.