Pendulum clock
A pendulum clock is a clock that uses a pendulum, a swinging weight, as its timekeeping element. It was invented in 1656 by Christiaan Huygens. From the year 1656 until the 1930s, the pendulum clock was the world's most accurate way of keeping time. This is what caused it to be used by a lot of people all over the place.It works on principle of periodic motion.
Pendulum Clock Media
A lantern clock that has been converted to use a pendulum. To accommodate the wide pendulum swings caused by the verge escapement, "wings" have been added on the sides
Animation of an anchor escapement, one of the most common escapements used in pendulum clocks