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In 1901, divers exploring an ancient shipwreck near the Greek island of Antikythera recovered a corroded lump of bronze. For decades few people understood what it was. Modern imaging finally revealed dozens of small gears fitted together inside the device. By turning a handle, an ancient user could track the movements of the Sun and Moon and predict eclipses. Built more than two thousand years ago, the Antikythera mechanism is now regarded as the oldest known device that worked like a mechanical calculator.

Recovered from a shipwreck, the Antikythera mechanism puzzled experts for many years. Modern scans showed that it contained dozens of tiny —gearsgemsgerms fitted together. By turning a handle, a user could follow the Sun and Moon and even —predictpreventproduce eclipses. Made over two thousand years ago, it is considered the —oldestloudestboldest known device of its kind.