Geoscience Reference
In-Depth Information
The energy in flowing and falling water has been harnessed to perform work by turning
waterwheels for more than 2,000 years. The moving water turns a large wheel and a shaft
connected to the wheel axle transmits the power from the water through a system of gears
and cogs to work machinery, such as a millstone to grind corn. An early description of a
water-powered mill for grinding grain is given by a Roman engineer named Vitruvius, who
compiled a treatise in ten volumes covering all aspects of Roman engineering, and the east-
ern Mediterranean is strongly associated with the first use of this technology, although a
separate tradition of using water power also emerged at about the same time in China. Ro-
man waterwheels were frequently connected to other forms of hydraulic engineering, such
as aqueducts and dams, designed to transport river water and control its flow to the wheels.
Multiple sets of Roman watermills for grinding grain into flour on a large scale are known
from the Krokodilion River near Caesarea Maritima in today's Israel, and from Chemtou
and Testour on the River Medjerda (the ancient Bagradas River) in the Roman cornbelt of
North Africa, part of Tunisia today. The mills just outside the town of Caesarea Maritima
consisted of four vertical waterwheels fed by an aqueduct from a dam on the river.
The power of rivers became widely used in the ancient world for milling grain but also for
other purposes. Water-powered mills were also developed to drive trip-hammers for crush-
ing ore and saws for cutting rock. All sorts of water-powered machines became more and
more common in medieval Europe, gradually taking over tasks from manual labour. The
early medieval watermill was able to do the work of between 30 and 60 people, and by the
end of the 10th century in Europe, waterwheels were commonly used in a wide range of
industries, including powering forge hammers, oil and silk mills, sugar-cane crushers, ore-
crushing mills, breaking up bark in tanning mills, pounding leather, and grinding stones.
Nonetheless, most were still used for grinding grains for preparation into various types of
food and drink. The Domesday Book, a survey prepared in England in AD 1086, lists 6,082
watermills, although this is probably a conservative estimate because many mills were not
recorded in the far north of the country. By 1300, this number had risen to exceed 10,000.
All across Europe, the watermills generally belonged to lords, to city corporations, or to
churches or monasteries. Cistercian monasteries were instrumental in the initial develop-
ment in England of the 'fulling' mill in the late 12th century. Fulling, or felting, was one in
a sequence of processes during the production of woollen cloth produced on the monastic
estates. It involved scouring and consolidation of the fibres of the fabric, both necessary
for proper finishing. The introduction of water-powered technology revolutionized fulling,
a process that had hitherto relied on human power to beat the cloth. On the Isle of Wight in
southern England, for instance, the first fulling mill was established at the Cistercian mon-
astery of Quarr Abbey on a stream close to large areas of pasture on the abbey's estates.
Wool from the flocks of sheep was processed at the abbey and sold in nearby towns.
