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THE PHOTOSPHERE AND SUN-SPOTS.
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The Photosphere and Sun-Spots.
of studying the superficial details as indices of the real nature of the structure, we are naturally led to inquire whether the surface before us is a solid like one of our continents, or a fluid like our seas, or a vapor like our clouds. We know, at the outset, from abundant evidence, that the temperature of the sun, whatever it may be, is far
