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by ubutler 823 days ago
One of my favourite episodes of Cosmos centres around Eratosthenes’ calculation of the circumference of the Earth: https://youtu.be/G8cbIWMv0rI?si=CuX49ki1GIvBLpeL
1 comments
drexlspivey 823 days ago
How did they take measurements in two different cities at the same time without clocks?
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wmanley 822 days ago
IIRC they walked directly north and measured at midday.
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