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Rh Halley adds to this beautiful description that the darkness was "more perfect," and the stars seen were more numerous, in some places than in others; but "the light of the ring was to all alike." From the north of England, too, he heard "that the luminous ring round the moon was seen there, which was nowhere visible but while the eclipse was total"! Nine years before Halley conjectured that the cause of the corona or ring lay, "probably, in those very vapours, which produce that pointed light, that has been observed lying in a manner along the ecliptic, and that has the sun for centre," the zodiacal light.

Into this traditional heritage of a lunar atmosphere Herschel passed, till the blindness of unreasoning belief was dispelled by facts. His atmosphere of the moon, his three volcanoes on its surface, and its fitness as a home for life, similar to what exists on the earth, were long cherished beliefs, that had all to be un-learned. Had the knowledge acquired from the total eclipses of the sun in 1706 and 1715 not been laid on the shelf and forgotten, he would not have fallen into these mistakes. Unfortunately, though twenty-eight solar eclipses occur every eighteen years somewhere on earth, no total eclipse has been seen from our island since 1716. A few years passed away, and, in 1792, Herschel came to the conclusion that we "have great reason to surmise that the moon's atmosphere," as well as that of Saturn's fifth satellite, is "extremely rare."

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