Eureka! · No. 4

How a stick and a shadow measured the whole world

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Eratosthenes · 에라토스테네스 — Alexandria, Egypt, c. 240 BCE

💡 The Idea

Eratosthenes' method rests on two facts: the Sun is so far away that its rays reach Earth essentially in parallel lines; and the Earth is a sphere.

📚 Grammar focus

Comparatives & Superlatives

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