C6

The head race is where the water from the pond flows into the mill.
A sluice gate works like a giant tap to control the flow of water on to the water wheel.

The force of gravity makes the water flow from the high ground to the low ground. Eventually, the water will flow back into the sea.

The water cycle brings the water back to the high ground so it can start it's journey all over again.

Where does the energy come from to make all this happen?