For many years Leonardo was also obsessed by the search for perpetual motion, that is the study of a system that could run endlessly from an initial boost. One of the most complex designs is described on folios 33v and 34r of Manuscript B.
The main element of the machine is a wheel with sixteen boxes. The weight inside them, behaving like a fluid that arranges itself in the position where it has minimum energy, forces the entire structure to rotate on its own, but only in theory. In fact, no matter how perfect the mechanisms are, attrition will inevitably occur and cause the machinery to slow down and finally stop.