Leonardo da Vinci designed a screw jack to lift and move heavy loads with mechanical advantage.
A screw jack uses the inclined-plane principle wrapped around a cylinder: turning the screw converts rotation into slow, powerful linear motion. Leonardo's engineering notebooks include lifting devices that use threaded screws, handles, and supporting frames to raise heavy objects. Such mechanisms could help with construction, military equipment, and workshop operations where direct lifting would require far greater force.
The screw jack was not a powered machine in the modern industrial sense. It relied on a person turning the mechanism, trading speed for force and precision. Leonardo did not invent the screw principle itself; screw-based lifting devices were known in antiquity and were discussed by earlier engineers. His contribution was to study and adapt mechanical arrangements in detailed Renaissance designs. A screw jack is also different from a crane, which generally raises loads with a rope, pulley, or winch rather than a threaded lifting member.