Water wheel at the Corn Mill, Cromford, Derbyshire

Using the water supplied from the Bonsall Brook, this overshot waterwheel provided the energy to power corn-grinding machinery. Overshot waterwheels, where water fell on the wheel from above were more effective than undershot water wheels. They used gravity as well as the force of water to create power. Undershot waterwheels were driven by waterpower from below.