THE BOOK OF INVENTIONS: THE WHEEL

 

The Wheel is one of the most important inventions in the history of mankind. The earliest picture of a wheel dates about 5500 years ago and is seen on the Standard of Ur, a mosaic which depicts an ancient civilization in Mesopotamia (now Iraq) around 6000 years ago. The picture shows a procession of heavy war wagons rolling along on wooden wheels.

These first wheels were solid wood and made of three pieces joined together with wooden struts or strips of leather. The two side pieces were shaped like a crescent moon and the central pieces had rounded edges with a hole through which the axle threaded so that the wheel could turn. These heavy, wooden wheels revolutionized transport, because they made the carrying of heavy and awkward materials so much quicker and easier. As the years passed, the spoked wheels were invented. The first spoked wheels appeared around 2000 B.C, and were used on Egyptian war wagons until 1500 B.C, making these faster and easier to drive.

Before the wheel, the first system people used to transport heavy loads was probably the sledge. They realized that tree trunks could be rounded, like rollers. These were laid under the sledge at each stage, and so, very, very slowly, it moved along. The wheel probably developed from using this technique, improved by inserting a spindle at the center of a wooden disc.