Hand Crank

From Rebirth of the Night Wiki

The Hand Crank is the earliest and most limited form of generating mechanical power. It serves as power for any machine that does not require continuous Mechanical Power. The Hand Crank is activated by directly interacting with it, a tiresome process. When activated, the Hand Crank will emit smoke particles. It can only be used to power one machine at a time; if it is adjacent to two or more, it will break into its components.

It's best used as the starting point in the process of obtaining the components for the much more powerful Windmill; That is, powering a Millstone to obtain Hemp Fibers.