Electrically driven pendulum

Electric pendulum, weighted above the centre, to beat seconds, in small compass

This pendulum system, patented by F. J. Ritchie in 1872, is maintained by electro-magnetic impulses due to currents received every second from a master clock of the Bain type.

It differs from other types in that the pendulum is loaded above its point of support. This pendulum, although beating seconds, need not be as long as the usual type, and so can be accommodated in a smaller space.