an hour after sunset
it was seen in great briliancy between Aldebaran and the Pleiades; and on
the 18th of March it attained an altitude of 39??degrees5'minutes. Narrow
elongated clouds are scattered over the beautiful deep azure of the distant
horizon, flitting past the zodiacal light as before a golden curtain. Above
these, other clouds are from time to time reflecting the most brightly
variegated colors. It seems a second sunset. On this side of the vault of
heaven the lightness of the night appears to increase almost as much as at
the first quarter of the moon. Toward 10 o'clock the zodiacal light
generally becomes very faint in this part of the Southern Ocean, and at
midnight I have scarcely been able to trace a vestige of it. On the 16th of
March, when most strongly luminous a faint reflection was visible in the
east." In our gloomy so-called "temperate" northern zone, the zodiacal
light is only distinctly visible in the beginning of Spring, after the
evening twilight, in the western part of the sky, and at the close of
Autumn, before the dawn of day, above the eastern horizon.
It is difficult to understand how so striking a natural phenomenon should
have failed to attract the attention of physicists and astronomers until the
middle of the seventeenth century, or how it could have escaped the
observation of the Atabian natural philosophers in ancient Bactria, on the
euphrates, and in the south of Spain.
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