Wheel

The wheel was a revolutionary invention by the Mesopotamians. It reduced friction in movement by rolling. The wheel is ideal for transportation applications where it is generally important to waste as little energy as possible.

## History[edit]

The ancient Mesopotamians invented the wheel originally in the form of a potter’s wheel. It then developed into a solid wooden disk with a hole in the middle for an axle. To make the wheel lighter and more practical the spoked wheel was developed. The Greeks used this type of spoked wheel. The Celts introduced a bronze rim around the outside of the wood to strengthen the structure. That was how the wheel remained, without major modifications, until the 1800’s when rubber (made from latex) tires started being developed.

In 1845, Scotsman Robert William Thomson patented the vulcanized rubber pneumatic tire in Scotland. Pneumatic means the tire is made from reinforced rubber and filled with air to provide a "...cushion of air to the ground." This type of tire was originally used on bikes but soon moved on to the automotive world. To this day, pneumatic tires are used on bikes and automobiles.

The rubber tire was never truly popularised until World War I, when the combined forces of the Triple Entente (Britain, France, and Russia) started using it for military vehicles against the Triple Alliance (Germany, Austria-Hungary, and Italy), before the incidence of trench warfare which would have made using vehicles useless for battle with the exception of the largely helpful tanks

## Alternatives to Wheels[edit]

There are many alternatives to using wheels for transportation over land. Different methods include:

* Human body (running or walking)
* Riding a horse or other mountable animal
* Dragging (as with a sled in arctic conditions)
* Magnetic levitation.
* Gondola