Ball, R[obert] S[tawell], Sir, 1840- [from old catalog] · New York, H. Holt and company · leaf 133
he earth in a circle, eq,which is called the equator. Since half this circlewill lie in the illuminated hemisphere and half in thedark hemisphere, it follows that the day and night atthe equator will be of equal length. At all placesbetween the equator and the Arctic Circle there willbe both…
Astronomy
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