Eratosthenes — "The sun's rays are parallel at great distances."
The sun's rays are parallel at great distances.
The sun's rays are parallel at great distances.
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"The world is full of wonders, if only one takes the time to observe."
"The world is not flat; it is a globe."
"One must observe the world carefully to understand its secrets."
"The circumference of the Earth is 250,000 stadia."
"I have calculated the length of the year with great care."
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