The History of the Water Wheel

The water wheel is an ancient device that uses flowing or falling water to create power by means of paddles mounted around a wheel. The force of the water moves the paddles, and the consequent rotation of the wheel is transmitted to machinery via the shaft of the wheel. The first reference to a water wheel dates back to around 4000 BCE. Vitruvius, an engineer who died in 14 CE, has been credited with creating and using a vertical water wheel during Roman times. The wheels were used for crop irrigation and grinding grains, as well as to supply drinking water to villages. In later years, they drove sawmills, pumps, forge bellows, tilt-hammers, and trip hammers, and even powered textile mills. The water wheel was likely the first method of mechanical energy developed to replace the work of humans and animals. Types of Water Wheels There are three main types of water wheels. One is the horizontal water wheel: Water flows from an aqueduct and the forward action of the water turns the wheel. Another is the overshot vertical water wheel, in which water flows from an aqueduct and the gravity of the water turns the wheel. Finally, the undershot vertical water wheel works by being placed in a stream and turned by the rivers natural motion. The First Water Wheels The first water wheels were horizontal and can be described as grindstones mounted atop vertical shafts whose vaned or paddled lower ends dipped into a swift stream. But as early as the first century, the horizontal water wheel—which was terribly inefficient in transferring the power of the current to the milling mechanism—was replaced by water wheels of the vertical design. Water Wheel Uses and Developments Water wheels were most often used to power different types of mills. A combination of the water wheel and mill is called a watermill. An early horizontal-wheeled watermill used for grinding grain in Greece was called the Norse Mill. In Syria, watermills were called noriahs.† They were used for running mills to process cotton into cloth. In 1839, Lorenzo Dow Adkins of Perry Township, Ohio received a patent for another water wheel innovation, the spiral-bucket water wheel. The Hydraulic Turbine The hydraulic turbine is a modern invention based on the same principles as the water wheel. It’s a rotary engine that uses the flow of fluid—either gas or liquid—to turn a shaft that drives machinery. Flowing or falling water strikes a series of blades or buckets attached around a shaft. The shaft then rotates and the motion drives the rotor of an electric generator. Hydraulic turbines are used in hydroelectric power stations.