d cart replaced the sledge as a means of transportation. In it's simplest form, the wheel was a solid wooden disk mounted on a round axle, to which it was secured by wooden pins. Eventually sections were carved out of the disk to reduce the weight, and radial spokes were devised by about 2000 B.C.E. This was another one of Mesopotamia's developments that was influenced by its climate and geography. The wheel was devised as a more efficient way to do agricultural work. It was an invaluable mechanical means for the controlling the flow and direction of power and force, an
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