In 1900, some divers found the wreck of a Roman vessel off the Greek island of Antikythera. Among the other treasures remanded to the Greek government was an unassuming corroded lump. Some time later, the lump fell apart, revealing a damaged machine of unknown purpose, with some large gears and many smaller cogs, plus a few engraved words in Greek. Early studies suggested it was some type of astronomical time-keeping device – researcher Derek J. de Solla Price laid the groundwork by establishing initial tooth counts and suggesting that the device followed the Metonic cycle, a 235-month pattern commonly used to predict eclipses in the ancient world.
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