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METEoric ShoWERS. 165
it up into the sky, being so bent downwards as to reach the eye. Among the most beautiful phenomena that greet the eye when contemplating the heavens in a serene night, but more particularly in autumn, the shooting stars, or meteors are preeminent; at almost all seasons of the year an attentive observer will perceive them moving swiftly over the heavens, and occasionally leaving a long luminous train behind. Their origin has not been satisfactorily traced, yet, since their occurrence in unusual numbers, and splendor, is now proved to be periodical, it is supposed they may be in some way connected with that beautiful luminous appearance called the zodiacal light. This is the opinion of Prof. Olmsted, who has devoted much time to this subject, and has been a careful investigator of the facts connected with meteors and the zodiacal light for many years. The “falling stars” seem to have been observed in the earliest times, and were considered as a presage of violent winds, thus Virgil — “And oft before tempestuous winds arise, The seeming stars fell headlong from the skies, And shooting through the darkness, gild the night With sweeping lines, and long trains of light.” The number of meteors visible at ordinary seasons of the year in one night, is quite limited, but we must remember that many of them are very small, and probably too distant to be observed by the unassisted eye. We have often witnessed the passage of meteors through the field of view of a night-glass when sweeping the heavens for comets, and have occasionally seen some very beautiful trains not at all visible to the unassisted eye. In the year 1833 a most remarkable display of falling stars was witnessed in the United States, but was not seen either in South America or Europe. It occurred on the morning of Nov. 13th, aud exceeded in magnificence any natural phenomenon we have ever witnessed; the whole heavens seemed glowing with fire-balls, which were falling in all directions. For many successive years this exhibition was repeated on the same morning, occurring most abundantly at about 4 o'clock, and apparently radiating from one centre, but each year their numbers diminished, and we believe that now, no more are visible upon on that night H*
than upon any other. Two other periods of unusual brilliancy seem to have been pretty well determined, viz: April 21st, and Aug. 10th. It is our opinion that these meteors, and the zodiacal light, are both of terrestrial origin, i.e. have their origin within the limits of our atmosphere. The greatest height at which these bodies occur is supposed to be about 2300 miles: at this height the atmosphere would be excessively rare, but it is probable that the upper strata are composed of shore inflammable materials than common air; hydrogen gas is continually being emitted by the great laboratory of nature, and ascends to the upper regions, here, when released from pressure it may expand to at least the distance, (and beyond it), where meteors occur. Sir John Leslie thus accounts for the lambent glow of the heavens in a clear night, supposing this stratum of highly inflammable gas to be phosporescent. We might perhaps trace the zodiacal light to the same source. This remarkable appearance is most conspicuous
phere about the sun. Laplace seems to have shown satisfactorily that such an atmosphere, far from extending to the earth, would not reach to even the orbit of Mercury. If this be so, we must either adopt the theory ef Von Humboldt, who supposes it to be a luminous ring surrounding the sun, or conclude it is of terrestrial origin. The preceding cut represents this beautiful phenomenon. It may be seen in our northern latitude in the spring months after sunset, reaching up in the plane of the ecliptic towards the Pleiades long after sunset; it gradually sets with the stars and may again be seen in the morning before sunrise. According to Sir John Leslie, the sun, shining upon the higher strata of the atmosphere, which he supposes phosphorescent, would form a large luminous circle which we would see surrounding the sun at noon, provided it was not eclipsed by his superior brilliancy; after sunset it would appear as a segment of a circle, did not the vapors of the horizen obscure its extreme and faintest limits, hence it appears lenticular, or lens shaped as represented in the engraving We shall conclude this chapter with a description of that well known, but yet unexplained phenomenon the Aurora Borealis or northern lights. In the high northern latitudes, beautiful displays of the aurora are witnessed, and they serve to enliven the tong winter nights with their bright coruscations. In our latitude the exhibitions are of a less beautiful character, and rarer, but yet so frequent that they are familiar to all. It generally appears like a bank, or cloud of light, of a pale yellow color, resting upon the northern horizon, occasionally emitting streamers which shoot up towards the zenith, and then fade, revive again, and subdivide. At other times it is seen as a luminous arch rising a short distance above the horizon, its highest altitude being in the magnetic meridian ; from this, streamers ascend, and if the display is a fine one, will appear to unite in a circle nearly in the zenith, called the corona. It is a remarkable fact that great displays of the aurora are always preceeded by a disturbance of the magnetic meedle. Like the meteoric showers, there seems to be a periodical return of the auroral displays in unusual splendor, after definite intervals. One of these returns, which we well remember, occurred at intervals from November 1835, to May 1836. The two following descriptions are from the pen of Professer Olmsted. The first display took place on the 17th of November 1835, the last on the 23d of April 1836. “On the 17th of November, 1835, our northern hemisphere was adormed with a display of auroral lights remarkably grand and diversified. It was observed at fifteen minutes before seven o'clock, when an illumination of the whole northern sky, resembling the break § day, was discernable through the openings in the clouds. About eighteen degrees east of north, was a broad eolumn of shining vapor tinged with crimson, which appeared and disappeared at intervals. A westerly wind moved off the clouds, rendering the sky nearly clear by eight o'clock, when two broad, white columns, which had for some time been gathering between the stars Aquila and Lyra on the west, and the Pleiades and Aries on the east, united above, so as to complete a luminous arch, spanning the heavens a little south of the prime vertical. The whole northern hemisphere, being more or less illuminated, and separated from the southern by this zone, was thrown into striking contrast with the latter, which appeared of a dark slate color, as though the stars were shining through a stratum of black clouds. The zone moved skowly to the south until about nine o'clock, when it had reached the bright star in the Eagle in the west, and extended a little south of the constellation Aries in the east. From this time it began to recede northward, at nearly a uniform rate, until twenty minutes before eleven, when a vast number of columns, white and crimson, began to shoot up, simultaneously, from all parts of the northern hemisphere, directing their course towards a point a few degrees south and east of the zenith, around which they arranged themselves as around a common focus. The position of this point was between the Pleiades and Alpha Arietis, and south of the Bee. Soon after eleven o’clock, commenced a striking display of those undulatory flashes denominated merry dancers. They consisted of thin waves or sheets of light, coursing each other with immense speed. Those undulations which play upon the surface of a field of rye, when gently agitated by the wind, may give the reader a faint idea of these auroral waves. One of these
AURORA BOREALis. r09
crimson columns, the most beautiful of all, as it ascended towards the common focus crossed the planet Jupiter, then at an altitude of thirty-six degrees. The appearance was peculiarly interesting, as the planet shone through the crimson clouds with its splendor apparently augmented rather than diminished.
A few shooting stars were seen at intervals, some of which above the ordinary magnitude and brightness. One that came from between the feet of the Great Bear, at eight minutes after one o'clock, and fell apparently near to the earth, exhibited a very white and dazzling light and as it exploded scattered shining fragments very much after the manner of a sky rocket.
As early as seven o’clock, the magnetic needle began to show unusual agitation, and after that it was carfully observed. Near eleven o’clock, when the streamers were rising and the corona forming, the disturbance of the needle was very remarkable, causing a motion of one degree and five minutes, in five minutes of time. This disturbance continued until ten o'clock the next morning, the needle having traversed an entire range of one degree and forty minutes, while its ordinary deflection is not more than four minutes.
Another-writer, speaking of the same appearance, says—We can compare the spectacle to nothing but an immense umbrella suspended from the heavens, the edges of which embraced more than half the visible horizon; in the south-east its lower edge covered the belt of Orion, and farther to the left the planet Jupiter shone in all its magnificence and glory, as through a transparency of gold and scarlet. The whole scene was indescribably beautiful and solemn. It was a spectacle of which painting and poetry united can give no adequate idea, and which philosophy will fail to account for to the satisfaction of the student of mature, or the disciple of revelation. The cause can be known only to HIM at whose bidding
Darkness fled—Light shone,
Flew upward, spirited with various forms
The appearance of April 23d 1836, is thus described by Olm