Chambers's Edinburgh Journal, No. 449, page 19 by Various Authors
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re than 13,000 feet above the sea-level.
'Those who have dwelt long,' he writes, 'in the zone of palms, must retain a pleasing remembrance of the mild radiance of this phenomenon, which, rising pyramidally, illumines a portion of the unvarying length of the tropical nights.' And once, during a voyage from Lima to Mexico, he saw it in greater magnificence than ever before. 'Long narrow clouds, scattered over the lovely azure of the sky, appeared low down in the horizon, as if in front of a golden curtain, while bright varied tints played from time to time on the higher clouds: it seemed a second sunset. Towards that side of the heavens, the light diffused appeared almost to equal that of the moon in her first quarter.'
The zodiacal light can hardly fail of having been observed by astronomers in the past ages of the world; but the earliest known mention of it occurs in the Britannia Baconica, published by Childrey in 1661. The writer says: 'There is another thing which I recommend to the observation of mathematical men--which is, that in February, and for a little before and a little after that month--as I have observed for several years together--about six in the evening, when the twilight hath almost deserted the horizon, you shall see a plainly discernible way of the twilight, striking up towards the Pleiads, and seeming almost to touch them. It is so observed any clear night, but it is best illæ nocte. There is no such way to be observed at any other time of the year. But what the cause of it in nature should be, I cannot yet imagine, but leave it to further inquiry.' The further inquiry followed soon afterwards, for Cassini, the eminent French astronomer, having carefully observed the phenomenon from 1683 to 1688, communicated the results to the Académie des Sciences. Some of his views and determinations were well founded; and from them we gather that the zodiacal light was nearly or quite the same in his day as at present. Others also devoted considerable attention