Wheel with shot balls

Wheel with shot balls

Inv. 2018
Interpretation by Giovanni Canestrini e Alessandro Siriati, 1956

"Thou speculators on permanent motion, how many useless drawings in this search have thou created! Go together with the gold seekers"

In Leonardo’s time, there was a very heated debate about the possibility of the realization of perpetual motion. This study shows the proof of the impossibility of producing an apparatus that will move without ever stopping. The model is constituted of a rotating disk upon both sides of which are mounted six halfwheels with steel spheres inside, able to fall in alternation through the force of gravity. When the disk is made to rotate, the spheres tend to fall by the force of gravity, but owing to the friction and other forces to which it is submitted, the disk quickly stops in a position of balance.

The model is based on the drawing:

  • Codex Forster II f. 91 r. (1487-1490)
    London, Victoria & Albert Museum