Self-propelling perpetual motion hydraulic system

Study for a hydraulic perpetual motion device consisting of a pair of pumps that move in alternating motion, feeding two nozzles. These spray alternately jets of water onto the blades of an impeller from two different directions. With its alternating motion, the impeller drives the pumps through a complex mechanical system consisting of gears, worm screws and racks. The water collected by the nozzles is conveyed into a tank from where it can be taken by the pumps to be used again. It is a theoretical experiment developed in the wake of the projects for recirculation mills which Leonardo had studied at the end of the 1470s (Codex Atlanticus, f. 1069r-v), characterised by considerable mechanical complexity, as if he were looking to solve the issue of perpetual motion through the combination of several elements. The analogy Leonardo draws between the limited duration in time of the machine’s operation and the life of living creatures is fascinating in the extreme: “And so, by turning, this water prolongs its motion for as long as the union of mechanical elements lasts, similarly to the living and animated bodies.” It is from this point of view that we should probably read the notes dedicated to anti-friction systems, aimed at reducing the heating and the consumption of the mechanical elements of the device described here.