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same cause, however, to a certain degree, would operate on its return. As a comet approaches its perihelion, its velocity is of course immensely increased, and the tail being but faintly affected by attraction, receives, in the acute turn of its orbit, a more powerful impulse of centrifugal force, and therefore would move foremost in the comet's passage from the sun, though necessarily diminished in length : and such we find is always actually the fact.
The question then arises, of what kind of matter are comets composed ? There seems to be but one which can reconcile the apparent incongruity of size not exerting strong attraction on other bodies, or which can bear out the contradictory assertions of astronomers respecting the transparency or opacity of the nuclei of comets and that one is, electric fluid, in that state in which it appears to us as the aurora borealis.
That the aurora borealis is electric fluid, rendered visible by the friction of the atmosphere, seems to be now scarcely doubted ; and we know that a spark from an electrical machine assumes the perfect appearance of a miniature aurora borealis in the nearly exhausted receiver of an air-pump. And when we consider that almost all bodies, by friction, become generators of electricity that the whole surface of our globe is one great manufactory - so to speak of electric fluid – it is evident that the immense quantity thus continually accumulating in the atmospheres of this and other inhabited worlds, must at length find some outlet — some safetyvalve to let off its superabundant streams. May not comets, then, afford the desired medium of keeping up the proper balance in this respect ? Arguments may be adduced, which go to prove that they do produce an effect upon our atmosphere, such as may be anticipated upon the supposition that these bodies are themselves electric. At all events, this supposition will enable us to account for many facts in natural philosophy, which otherwise appear to be perfectly enigmatical.
1. It appears, from researches made by M. Arrago, that those seasons in which comets have appeared, have been remarkably cold and unpleasant; and it is certain that the past year has borne ample testimony to the general fact. In what way is coincidence to be accounted for, unless by supposing that the comets collect from the atmospheres of the earth, and of the other planets which lie in their path, a large portion of the electric fluid, and, consequently, perhaps, latent heat which they contain ?
No slight force and probability are added to this supposition, by calling to mind what will readily be admitted by every one, that during the season which immediately preceded the last arrival of Halley's comet, a very unusual number of electrical phenomenæ appeared in our atmosphere. Rarely were such beautiful displays of the aurora borealis witnessed seldom were so many accidents from lightning recorded. It is a remarkable fact, that the year just elapsed has been unusually deficient in these occurrences.
2. The astronomer Massarotti,* considers comets capable of affording demonstration of a resisting medium in the heavens, and we may, without any very great stretch of the imagination, suppose the
Vide Encyclopædia Americana — article 'Comets.'
atmospheres of the planets to extend, in a highly rarified state, till they unite with each other. As far as experiments on atmospheric air have yet enabled us to judge, it would almost appear that its elasticity is unlimited; and in the higher regions, where all pressure is removed from it, except that which proceeds from the attraction of the body which it surrounds, there seems nothing improbable in supposing that a single particle may be so attenuated as to cover a surface of several square miles, yet sufficiently dense to serve as a conducting medium for the electric fluid.
Under these suppositions, we may account for the increased length of tail which comets exhibit, as they approach their perihelion. Řeceiving, as they pass, accumulations of electricity from the planets, their volume becomes enlarged, at the same time their velocity being accelerated through this ' resisting medium,' or rarified atmosphere, friction is produced, sufficient to render the electric fluid more brightly visible.
There is still another fact bearing on this part of our subject. It was stated by some of the European astronomers, that in observing Halley's comet with powerful telescopes, an appearance of three, or, as others affirmed, five tails, was observed. On any other than the electric theory, this would seem quite unaccountable; and many, indeed, were inclined to think that the philosophers were either deceiving or deceived. But considering the subject in the light in which it is here presented, what is more probable than to suppose such tails or streams of light to be currents of electric fluid, passing off from the atmospheres of the nearest planets, and becoming visible as they approached the comet, in consequence of the increased velocity which proximity must produce ?
3. Warm, moist air is a good conductor of electricity. Hence we find, that in the regions comprised within the torrid zone, thunder-storms are more frequent and more terrific than in higher latitudes. In connexion with this circumstance, looking upon comets as vast masses of electric fluid, it is not impossible that some light may be thrown upon the hitherto unexplained fact, that the tail of the same comet subtends a larger angle, when viewed from the equatorial regions, than it does from more northern or southern countries. The comet of 1768-9, as observed at Paris, exhibited a train of 60°. At the same time, from on board a ship between Cadiz and Teneriffe, it appeared to be 90°, and at the Isle of Bourbon, 970. It is difficult to say in what manner a highly electric atmosphere magnifies the comet's tail, without producing the same effect upon the other heavenly bodies; yet looking upon them as homogeneous, the fact appears to wear a less formidable aspect.
The last circumstance to be adverted to, is the well-known fact, that while all the other bodies of our system move round the sun in one direction, the comets appear bound by no such restriction. Some are direct some retrograde. This circumstance, if it has no other force, yet at least seems to militate against the probability of their being solid bodies — for if they were, why should they not follow the universal law by which all the bodies known to be solid are directed ? And if they are not solid bodies, it will at least appear probable, that the matter of which they are composed is more likely to be electric fluid than any other with which we are acquainted. And if the
nucleus be a concentration of that fluid, attracted forward to one point by the influence of the sun, at one time so bright as to overpower the brilliance of a fixed star behind it, at another so faint as to allow its rays to pierce through, it will afford, what no other supposition can, a reason why astronomers have been divided in their opinions on this point, supposing the opinions of both parties to have been correctly formed.
If it be asked what becomes of the immense quantities of electricity carried off from the planets by the comets, it may be replied, in the language of the old-fashioned definition of a comet, It is the sun's fuel-carrier.' And it may be a literally correct definition. It does not appear that any absurdity is involved in the supposition, that the sun (particularly if light, as many suppose, is material,) is constantly giving out a portion of his substance to the surrounding orbs, and that the waste is repaired by the comets, which in their perihelion may give out to that body the stores which they have collected in their erratic wanderings. Certain it is, that on their return from the great luminary, they appear with diminished size, and less extent of tail ; and there is no reason to be assigned why this should not proceed, in part at least, from the cause before mentioned.
The theory here adduced, like most other theories, does not admit of proof. Its highest boast is, that it has probability on its side,
and that it enables us to reconcile difficulties in respect to the nature of comets, and their effects upon our atmosphere, which no other can. The writer does not expect to make converts to his opinions by these remarks, loosely thrown together: he will be perfectly satisfied, if he succeeds in drawing attention to the subject, leaving it to more able hands to finish the structure of which he has merely drawn a rough and undigested plan.
J. H. C.
Wo! for the land thou tramplest o'er,
INFOLDED in a gory sheet,
They bear him to his shallow grave,
A martial requiem for the brave :
Morn gilds the grave of Valor. Birds
Are trilling songs in copsewood nigh,
First caught by lisping infancy.
THE MARINE FREE BOOTER:
AN AUTHENTIC STORY OF ROBERT KIDD, AND HARLEY, THE LONG-ISLAND WRECKER.
My name was Robert Kidd,
As I sailed.'
Who has not heard of Captain Robert KIDD? What man, with a spice of superstition in his nature, has not listened, when a boy, with a strange interest, to many various and highly spiritual traditions concerning him ? A most remarkable man was that same pirate, who for so long a period evaded the pursuit of both England and her American colonies, until at last, in the year 1699, if I remember aright, he was captured, and sent by Lord Bellamont a prisoner to Xis Majesty, at London, where, at Execution Dock," he was executed, in atonement for divers robberies and murders committed by him on the high seas, ' as he sailed. I record below one of the traditions of this world-renowned freebooter, which was related to me by a firm and solemn believer in its reality over, who possessėd a sound and comprehensive mind, in union with the strictest religious principles.
Kidd, as is well-known, was supposed to have buried vast quantities of money, much of which is still believed to sleep in the bowels of the earth, along various portions of the Atlantic coast. After his death, numerous attempts were made to recover it, by effecting a resurrection among the iron chests of specie, and yellow bars of gold. It is supposed that the bulk of his spoils was deposited on the shores of New Jersey and Long-Island, and the margin of Connecticut River. He always selected some shadowy and romantic spot, far away from the busy settlements of the whites, whither he repaired, under cover of a nocturnal storm, to commit his wealth to the guardianship of the earth, and the magic power which he so enchantingly flung around it.
Long-Island has long been famous for the number of wreckers who infest its coasts.* This class of people made it their business to decoy vessels among the breakers, by elevating false lights, and so disguising the genuine beacons, as to throw all the ship-commanders into doubt and confusion. These schemes were more particularly resorted to, when the heavens portended a furious gale, and the wind blew strongly toward the land. The wreckers, with their vagabond families, usually resided in miserable huts, near the beach, screened by the shadow of some impenetrable wood, or still more impenetrable wild and rocky upland. Their plunder, which consisted of specie, silks, satins, broadcloths, barrels, etc., was buried on the seashore, above high-water mark, and there suffered to remain until the underwriters had made sale of the wreck, when they were transported to New York, and disposed of at the various junk-shops, etc., which have for so long a time infested the city.
*Jim Harley,' as he was familiarly termed, had from his youth pursued this most unworthy occupation. His father, who had been
* Its reputation in this respect is but little diminished. Witness the scenes attending the receni wreck of the Bristol.