Water Wheel Stock Photo

Hellenistic engineers invented the water wheel and were, along with the Romans, the first to use it for both irrigation and as a power source. The technological breakthrough occurred in the technically advanced and scientifically minded Hellenistic period between the 3rd and 1st century BC. Chinese water wheels almost certainly have a separate origin, as early ones there were invariably horizontal water wheels. By at least the 1st century AD, the Chinese of the Eastern Han Dynasty were using water wheels to crush grain in mills and to power the piston-bellows in forging iron ore into cast iron. The early history of the watermill in India is obscure. Ancient Indian texts dating back to the 4th century BC refer to the term cakkavattaka (turning wheel), which commentaries explain as arahatta-ghati-yanta (machine with wheel-pots attached).