In fact, water clock was the ancestor of our mechanical clocks. Let us perform an activity to understand the working of a water clock.

These clocks of early times however, were inconvenient to use because the sundial could not be moved form one place to another place and sand and water clocks had to be attended regularly.

The real advancement in the construction of clocks came with the introduction of the pendulum. Let us see how pendulum helped us in measuring time.