The Earliest Levers

In the third century BC, the Greek mathematician Archimedes became perhaps the first person to explain the mechanical advantage of the lever. However, farmers in ancient Mesopotamia and Egypt were already using levers about 1,500 years before that.

These farmers built a machine called a shadoof to help them water their fields. The shadoof has a tall, wishbone-shaped fulcrum with a long pole laid across it. The fulcrum is much closer to one end of the pole than to the other. A bucket is hung from the long end of the pole. A clay weight is hung from the short end. The mechanical advantage of the pivoting pole makes it easy to dip the bucket into a river, fill it, then lift it up to water the ground. Some people in Asia and Africa still use these levers for lifting water today.

The fulcrum of a shadoof sits between the effort and the load, making it a first-class lever. This man is using a shadoof to lift water from a deep well.View Larger Image

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