Congreve Rolling Ball Clock

In 1808 Sir William Congreve invented a type of clock that uses a ball rolling along a zig-zag track rather than a pendulum to regulate the time. It is known as Congreve's Rolling Ball Clock or Oscillating Path Rolling Ball Clock.


Unfortunately these clocks are unreliable timekeepers — the time taken for the ball to travel along the track varies greatly depending on the cleanliness of the track and ball, and since the plate is aligned horizontally, it is easy for dust to accumulate.

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