Roman Water Mill

• The Romans used water power to grind grain and to provide power for some early mechanical forges. Water mills have been found throughout the Roman Empire.
• The Romans tended to use a vertical wheel with a horizontal shaft, although some horizontal wheels with a vertical shaft resembling a turbine, have also been found.

Janiculum Hill Watermills in Rome

• These watermills were used to grind the grain for Rome.
• They were built into the Aurelian Walls in Rome.
• They most probably used a system of undershot wheels and used water from an aqueduct at the top of the Janiculum hill which had a steep drop.

Barbegal Water Mills, Gaul

• Using the downward pipe of an aqueduct, a series of mill wheels were connected together using the overshot method.
• By inventing the overshot wheel, the  efficiency of the Mills at Barbegal in Gaul, was increased 8 times more than the traditional undershot wheel.