The wheel has proved to be one of the most enduring and useful pieces of human technology. It was probably first invented in the 4th millennium BCE , and became a useful means of transporting heavy loads. It remains in widespread and growing use.
For brevity’s sake we refer to ‘the invention of the wheel’, but it is the combination of wheel and axle that comprises the key technology. Of course, the most obvious use is in transport, but numerous other machines rely on wheels, in the form of flywheels, cogged gear wheels, and so on. The first archaeological evidence of a wheel, found in Mesopotamia, and dated to around 3500 BCE , was probably a potter’s wheel, although those may have been invented a thousand years earlier (see here ).
A wheel is more than just a rolling cylinder. Such rollers, shaped from tree trunks, were probably in use long before the wheel–axle concept came along, and served to move heavy loads, like large stones, short distances. The wheel–axle combination reduced the friction between the ground and the rolling cylinder, and joined it to a stable platform. The technology brought challenges, however. Each end of the axle, together with the holes in the centre of the wheels, had to be smooth and round, otherwise there would be too much friction for the wheels to rotate. The first wheels were solid slices of wood, before the introduction of the wooden spoke around 2000 BCE made for a much lighter, better-sprung device.
There is some debate as to where and when the first wheel–axle combination was invented. Mesopotamia and various parts of the Eurasian steppes have both been proposed, with dates between 3300 and 3000 BCE . In these parts of the world wheeled vehicles would at first have been pulled by oxen alone, but the domestication of the horse and wild ass around 3000 BCE provided faster pulling power. It was not long before the agricultural cart was adapted for warfare as the chariot (see here ).
‘When man wanted to imitate walking he created the wheel, which doesn’t look like a leg.’
Guillaume Apollinaire, French poet, introduction to
Les Mamelles de Tirésias (1917)
Wheeled vehicles came into use in China in the 2nd millennium BCE , and subsequently across much of Eurasia, but were never used by pre-Columbian Americans, probably because suitable draught animals were not available. The llama is not strong enough to pull a cart, while the North American bison resisted domestication (wild horses had become extinct in the Americas around 12,000 years ago).
