Eratosthenes computes the size of the earth - 230 B.C. [in English]
Channel: mayankacademy
Date: 23/08/2013

In this lecture, we talk about how the ancients argued that the earth was round, and how 
Eratosthenes, in 230 B.C., using sticks and shadows gave us a remarkably close estimate of the size of the earth.

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