Those who have lived for many years in the zone of palms must retain a
pleasing impression of the mild radiance with which the zodiacal light,
shooting pyramidally upward, illumines a part of the uniform length of
tropical nights. I have seen it shine with an intensity of light equal to
the milky way in Sagittarius, and that not only in the rare and dry
atmosphere of the summits of the Andes, at an elevation of from thirteen to
fifteen thousand feet, but even on the boundless grassy plains, the Illanos
of Venezuela, and on the sea-shore, beneath the ever-clear sky of Cumana.
This phenomenon was often rendered especially beautiful by the passage of
light, fleecy clouds, which stood out in picturesque and bold relief from
the luminous back-ground. A notice of this a?‘rial spectacle is contained
in a passage in my journal, while I was on the voyage from Lima to the
western coasts of Mexico: "For three or four nights (between 10??degrees
and 14??degrees north latitude) the zodiacal light has appeared in greater
splendor than I have ever observed it. The transparency of the atmosphere
must be remarkably great in this part of the Southern Ocean, to judge by the
radiance of the stars and nebulous spots. From the 14th to the 19th of
March a regular interval of three quarters of an hour occurred between the
disappearance of the sun's disk in the ocean and the first manifestation of
the zodiacal
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light, although the night was already perfectly dark.
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