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dread as the forerunner of the victory of William of - Normandy. It was then equal to the full moon in SOIt size. In 1456, its tail reached from the horizon to ce!" the zenith. It was supposed to indicate the success It # of Mahomet II, who had already taken Constanti
*: nople, and threatened the whole Christian world.
in June, it was 240,000,000 miles from the earth. In August, traces of a tail were noticed, which expanded in October to about 50,000,000 miles in length. This
DESCRIPTION.—If we watch the western horizon in March or April, just after sunset, we shall sometimes a faint, nebulous light, of a conical shape, flashing upward, often as high as the Pleiades. In September and October, at early dawn, the same appearance can be detected near the eastern horizon. The light can be seen in this latitude only on the most favorable evenings, when the sky is clear and the moon absent. Even then, it will be frequently confounded with the Milky Way or auroral lights. At the base it is of a reddish hue, where it is so bright as very often to efface the smaller stars. In tropical regions the zodiacal light is perpetual, and shines with a brilliancy sufficient, says Humboldt, to cast a sensible glow on the opposite part of the heavens. ORIGIN.—The commonly received opinion is, that it is caused by a faint cloud-like ring, perhaps a meteoric zone, that surrounds the sun, and only becomes visible to us when the sun himself is hidden below the horizon. Others maintain that, since it has been seen in tropical regions in the east and west simultaneously, it can be explained only on the theory of a “nebulous ring that surrounds the earth within the orbit of the moon.”