Description

Arasta-powered overshot water wheel, Yavapai County, Arizona Territory, c. 1910's. 

Handwriting on the back of the photograph says: "Arastra wheel overshot used in mining." 

The earliest, simplest and most affordable method of crushing ore was with the use of an arrastra. Arrastras (also “rastra” or “arastra”) had their origins in Mexico. They were used during the California Gold Rush of the 1850s. These devices consisted of a flat track of stone inside a low wall of rock or wood, a retaining basin to capture and hold the ore, and a center post and horizontal shaft made of wood or from small tree trunks. The ease by which they were built and operated made them ideally suited to small mining operations. Powered by horse or mule, the shaft would drag one or more large stones in a circular path on top of the flat stone base, crushing the ore that has been placed in the basin.

When water was plentiful, flumes and water wheels were often used instead of animal power. 

A waterwheel was one of the most important sources of energy. It was invented and used since ancient times. Water wheels were placed next to areas of moving water such as rivers or streams and in canals. They harnessed moving water to generate milling and concentrating machinery. When the flow was sufficient, the water wheel used flowing or falling water to create power by means of paddles or buckets mounted around the wheel. The energy they generated was then re-directed to mechanical devices and other uses where “power” was required.

There were three types of water wheels, including overshot, undershot, and breastshot wheels. Each type of waterwheel operates according to how its' source water interacts with the wheel. Overshot wheels are powered by water flowing over its' top. Undershot wheels are powered by water flowing underneath it. Breastshot wheels are powered by water entering at the side of the wheel.

Water wheels were a precursor to modern hydroelectric power generation.