Note: Do not rely on this information. It is very old.
Electric Clocks
Electric Clocks are those whose motive power is supplied by electricity. The pendulum may be acted on by an electro-magnet so arranged that it pulls the pendulum first one way and then the other; no weight or spring is then required. Or the weight may be lifted up periodically by an electric current, thus rendering the clock self-winding. A very useful application of electricity to clocks is the rendering of a number of them perfectly synchronous. If a series of similar clocks with pendulums of equal length be worked by the same current, they can be made to tick simultaneously, and so record the same time always. Such an arrangement is specially useful on railways.