Wheels

A wheel is a circular object that, together with an axle, allows low friction in motion by rolling. Common examples are found in transport applications. More generally the term is also used for other circular objects that rotate or turn, such as a Ship's wheel and flywheel. more...

History of the wheel and axle

Notably, there are no wheels in animals or plants though some animals can roll. The wheel is regarded as one of the oldest and most important inventions which, according to most authorities, originated in ancient Mesopotamia during the 5th millennium BC, originally in the function of potter's wheels. Records show that wheels appeared almost simultaneously in Mesopotamia and Europe. The wheel reached India with the Indus Valley Civilization in the 3rd millennium. In China, the wheel is certainly present with the adoption of the chariot in ca. 1200 BC, and Barbieri-Low (2000) argues for earlier Chinese wheeled vehicles in, from maybe 2000 BC.

Although they did not develop the wheel proper, the Olmec and certain other western hemisphere cultures seem to have approached the concept, as wheel-like worked stones have been found on objects identified as children's toys dating to about 1500 BC. The wheel was apparently unknown in sub-Saharan Africa, Australia, and the Americas until relatively recent contacts with Eurasians.

The invention of the wheel thus falls in the late Neolithic and may be seen in conjunction with the other technological advances that gave rise to the early Bronze Age. Note that this implies the passage of several wheel-less millennia, even after the invention of agriculture.

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