A dictionary-size assemblage of 37 interlocking dials crafted with the precision and complexity of a 19th-century Swiss clock, the Antikythera mechanism was used for modeling and predicting the movements of the heavenly bodies as well as the dates and locations of upcoming Olympic games.A replica has been created that is said to work perfectly:
The original 81 shards of the Antikythera were recovered from under the sea (near the Greek island of Antikythera) in 1902, rusted and clumped together in a nearly indecipherable mass. Scientists dated it to 150 B.C. Such craftsmanship wouldn't be seen for another 1,000 years — but its purpose was a mystery for decades.
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People often wonder why ancient Greece's technology was so largely lost. The main reason is, in the centuries following the collapse of Rome, Europe - which might have been expected to retain the technology - was fragmented and under constant siege from pirates and bandits, who destroyed irreplaceable manuscripts. In fact, as Thomas Cahill explains in How the Irish Saved Civilization,
Not only did Irish monks and scribes maintain the very record of Western civilization -- copying manuscripts of Greek and Latin writers, both pagan and Christian, while libraries and learning on the continent were forever lost ... [so that when] the seeds of culture were replanted on the European continent, it was from Ireland that they were germinated.The main thing to see here is not where the manuscripts were, but where they weren't. For many centuries, most people simply did not have access to things like antikythera or the writings that were anchored its civilization. Gradually, by the early Middle Ages, national governments started to win the fight against bandits and pirates, at which point universities became possible.