Eureka!
The Screw and the Wheel
All machines in the world can be traced to just two: the inclined plane and the lever. Even the wheel is just a circular lever whose fulcrum has become an axle. The screw? It's just a spiraling inclined plane.
All machines in the world can be traced to just two: the inclined plane and the lever. Even the wheel is just a circular lever whose fulcrum has become an axle. The screw? It's just a spiraling inclined plane.