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On top of that, you don't even an ocean to measure the Earth's circumference. Eratosthenes of Cyrene (born in the 3rd century BC) calculated the circumference o
by antiform 18y ago
On top of that, you don't even an ocean to measure the Earth's circumference. Eratosthenes of Cyrene (born in the 3rd century BC) calculated the circumference of the earth fairly accurately using the angle of elevation of the Sun measured from two different cities. Note that implies that a round earth was common knowledge to the Greeks even at this date.