Featured Artifact – Water Saw Mill

Roman sawmill at Hierapolis

Hierapolis water-powered stone saw mill

The Hierapolis sawmill was a Roman water-powered stone sawmill at Hierapolis, Asia Minor, modern-day Turkey. Dating to the second half of the 3rd century AD, the sawmill is the earliest known machine to combine a crank with a connecting rod.

Roman sawmill at Hierapolis

Scheme of the water-driven Roman sawmill at Hierapolis, Asia Minor. The 3rd century mill is the earliest known machine to incorporate a crank and connecting rod mechanism

The watermill is evidenced by a raised relief on the sarcophagus of a certain Marcus Aurelius Ammianos, a local miller. On the pediment a waterwheel fed by a mill race is shown powering via a gear train two frame saws cutting rectangular blocks by the way of connecting rods and, through mechanical necessity, cranks. The accompanying inscription is in Greek and attributes the mechanism to Ammianos’ “skills with wheels”.

A description of two ancient Roman watermill complexes, the Janiculum watermill complex at Rome and the Barbegal watermill complex near Arles in southern France. The watermill complex at Barbegal has been referred to as “the greatest known concentration of mechanical power in the ancient world”. Apart from water-powered flour mills, water-powered sawmills for cutting marble and stone were also in use in the Roman Empire, for instance the 3rd century Hierapolis sawmill…

There are three basic types of waterwheels, each with its own advantages and disadvantages. Each type has been in use since at least Roman times, and remained remarkably stable from AD500 to the mid-1700s, when a new type, turbines, began displacing them, but their heyday is beyond the time period of this lesson.

The three types of waterwheels are the horizontal waterwheel, the undershot vertical waterwheel, and the overshot vertical waterwheel. For simplicity they are simply known as the horizontal, undershot, and overshot wheels.

Overshot Water Wheel

Overshot Water Wheel

Undershot Water Wheel

Undershot Water Wheel

Breastshot Water Wheel

Breastshot Water Wheel