This model illustrates Galileo's idea of improving the precision of mechanical clocks by exploiting the principle of isochronism of a pendulum's short oscillations.

Mechanical clocks are formed of a motor (a weight or spring), a transmission device (wheelwork), a supplying device (escapement) and a regulator device (pendulum or balance wheel). The escapement keeps the regulator operating and the regulator provides for isochronous motion.