An ancient Greek lunar calculator - the first "computer" - is found to be more complex than expected.
But a century ago, pieces of a strange mechanism with bronze gears and dials were recovered from an ancient shipwreck off the coast of Greece. Historians of science concluded that this was an instrument that calculated and illustrated astronomical information, particularly phases of the Moon and planetary motions, in the second century B.C.
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Dr. Charette noted that more than 1,000 years elapsed before instruments of such complexity are known to have re-emerged. A few artifacts and some Arabic texts suggest that simpler geared calendrical devices had existed, particularly in Baghdad around A.D. 900.
It seems clear, Dr. Charette said, that “much of the mind-boggling technological sophistication available in some parts of the Hellenistic and Greco-Roman world was simply not transmitted further,†adding, “The gear-wheel, in this case, had to be reinvented.â€
Hard to imagine this type of technology gap ever reoccuring short of a planetary catastrophe.
Full article from the NY Times (free reg required)