The Antikythera Mechanism
The main fragment of the Antikythera mechanism, a geared bronze astronomical calculator of the 2nd century BC, in the National Archaeological Museum, Athens.
Recovered in 1901 by sponge divers from a Roman-era shipwreck off the Greek island of Antikythera, this corroded lump of bronze proved to hold the most sophisticated machine known from all antiquity. Behind its surviving gearwheel lay a hand-cranked device of at least thirty interlocking bronze gears that modeled the heavens: it tracked the sun and moon through the zodiac, predicted eclipses, and followed the four-year cycle of the athletic games. Nothing of comparable complexity survives for well over a thousand years afterward — a startling glimpse of the astronomy and engineering of Hellenistic Greek scholarship.
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