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dove, that I might flee away and be at tell. This is a sorry confession to make ; rest.
but I will not ape a spiritual sublimity which I do not feel.
SOUTHEY Whereas I cling to this present state of You set too great and exclusive a value on being, with a tenacity that becomes deeper things seen and temporal ; but I'm not goand firmer with every furrow in the soil of ing to be dogmatical with you. For my part, my heart. I shrink from the thought of new my very happiest moments are those when and untried existence. I would never leave I am anticipating that future life where familiar faces and familiar scenes. Thoughts change shall be ever for the better, and proof an expanded and elevated sphere, instead gress shall be without decay, and happiness of consoling, depress me more than I can without evanescence.
From Hogg's Instructor.
In the ages of ignorance and superstition, Sir Isaac Newton believed that the orbit very wild and extraordinary opinions have of the comet of 1680 would become gradubeen entertained regarding the nature of ally less, and that at last the comet would comets, and the purposes for which they ap- fall into the sun ; thus, in his opinion, fulfillpear in the heavens. The ancient Chaldeans, ing one of the uses of comets, namely, to and Pythagoras, with some of his followers, be furnish fuel for the sun, which was supposed lieved them to be of the nature of the planets. to be necessary, to prevent the sun from Aristotle supposed them to be meteors in the being wasted away by giving out so much upper heavens, generated when they appear light. Mr. Brydone seemed to hold the ed, and vanishing out of sight by being same opinion with regard to almost all the destroyed. In later times, Kepler, noted for comets without tails, which he alleges are the wildness of his imagination, as well as for seen approaching the sun, but of whose the strength of his genius, fancied comets return from the sun no evidence satisfactory to be monstrous and uncommon animals gen- to him was ever given. Such were the erated in the celestial spaces. Bodin, a opinions of pbilosophers regarding comets, French writer of the sixteenth century, main before the accurate observations, superior intained that comets “are spirits, or genii struments, and profound calculation of moddifferent from men, yet mortal, which, having ern science made us better acquainted with lived on the earth innumerable ages, and them. being at length arrived on the confines of Whilst the learned formed conjectures redeath, celebrate their last triumph, or are garding comets that were wide of the truth, recalled to the firmament, like shining stars." ignorance and superstition invested them An opinion something like this, extravagant with a mysterious and awful significance. though it be, prevailed in remote ages; for They were regarded as omens or forerunners we find that the people generally believed of war, or pestilence, or famine; of the birth that a great comet which appeared immedi. of mortals who were to be great for good or Ately after the assassination of Julius Caesar, evil among their fellows ; or of those calamiwas the soul of that celebrated mai. The ties which too often followed the death of conjecture—for all was yet only conjecture, the great conquerors of antiquity. Princes, of Bernoulli, an Italian philosopher, was popes, peoples, were perplexed and alarmed nearer the truth, and yet far from it: He by the appearance of these strange wanderthought that comets were the satellites of ers in the heavens, as they glared down in some far-off planet, invisible on account of their fiery splendor, or gave forth their pale, its stance, which wander betimes within livid, watery light, the very emblem, as men the sphere of our vision.
thought, of plague and famine ; or as their immense trains swept across the heavens, 1 greater or less condensation. The celebrated attracting every eye, and filling men's hearts French philosopher Arago was of opinion with astonishment and anxiety.
that some comets are solid bodies like the Speaking of Mithridates the Great, king of planets; and he rested that opinion very Pontus, the historian Justin says, “The celes much on an alleged fact, that a comet has tial signs had foretold the future greatness been observed as a round black spot on the of this man. For, in that year in which he body of the sun, in its transit across the disc was born, and in that in which he first began of that luminary, like the planets Mercury to reign, the star of a comet, through each and Venus in similar circumstances. There time, so shone for seventy days, that all the is the strongest reason to believe, however, heaven seemed to be in a blaze. For it had that what have sometimes been taken for taken up the fourth part of the heaven by opaque or planetary nuclei, were nothing but the greatness of it, and had overcome the the nebulous or gaseous matter of which brightness of the sun by the splendor of it; comets are composed, in a very high state of and it occupied the space of four hours in condensation. It having been computed that rising and setting.” A comet which appear the comet of 1827 would cross the sun's ed in 837 so alarmed the reigning king of disc, the occurrence was looked forward to France, Louis I., that he ordered a number with much interest, as fitted to furnish the of churches and monasteries to be built best information regarding the nuclei of comthroughout his dominions, in the hope that ets. Unfortunately, the sun at the computed thereby he would appease the wrath of Heav- time was hidden by clouds in this country; en, of which he supposed the comet to be he was seen, however, by the French observ. an indication. And in 1446, the pope of ers at Verviers and Marseilles ; but no spot that day, Calixtus III., hard pressed by the or cloud could be discovered on the sun's successes of the Turks under Mahomet II., disc; and hence it was concluded that the was greatly alarmed by the appearance of a comet had no solid or opaque part whatever. remarkable comet, and he appointed a form Besides, when comets bave presented to the of prayer to be used against its supposed observer what seemed to be a solid planetary baleful influence; and, for the same end, he disc, it has been found that the appearance ordered the bells in all the churches to be rung of that disc underwent changes of shape every day at noon. But, “ Thus saith the and character altogether inconsistent with Lord, be not dismayed at the signs of heaven, the fact of it being a solid substance. And for the heathen are dismayed at them.' it is held to be doubtful whether a single in
Though much has yet to be learned re. stance can be produced of a comet with a garding comets, the observations and labors planetary disc presenting the same appear. of modern science have led to a good deal | ance throughout the whole period that it was of trustworthy knowledge of them, and have observed. Indeed, the changes exhibited by shown them to be very harmless, but very the central portion of the heads of comets interesting celestial phenomena. In this pa- in other words, the different appearances per we shall attempt to give a rapid sketch of presented by the disc, in those of them what is known regarding comets, and espe. which are so furnished—are among the most cially of the results of recent investigations, puzzling of the phenomena connected with drawing our materials chiefly from the work ihese bodies. of Mr. Hind.
The nuclei of different comets present very Some comets are distinctly, and even con- different appearances, and even the nucleus spicuously visible to the naked eye; others of the same comet evidently undergoes, as we (and these by far the greater number) are have just stated, great and surprising changes. only to be seen by the aid of the telescope. A remarkable comet appeared A. D. 389, In almost every instance in which they are whose head seemed composed of several conspicuously visible to the naked eye, com- small stars. The nucleus of the comet of ets consist of a bead composed of a nucleus 1835-36, usually called Halley's comet, preof light surrounded by a mass of nebulous sented at one time the appearance of a fanmatter, and of a tail or train of nebulous shaped flame, proceeding from a bright point: light stretching out from the head or nucleus. at another time, it was like a red-hot coal of
When we direct the eye or the instrument an oblong form; at another time, it was seen to the head of a comet, we see sometimes a as a well-defined disc, with an apparent diamstar-like body in the centre, sometimes a eter of not less than 97,000 miles; and at disc-like appearance, and sometimes evident. another time, as a brilliant kernel of light, ly only the nebulous matter, in a state of l with a diameter varying from 250 to 1,000
VOL. XXXIV.-NO. III.
miles. The comet of 1807 was seen by Sir | that have attracted the attention of mankind, W. Herschel to have a well-defined planetary and filled them with astonishment, and often, disc of a circular form. Sir William also saw in the days of ignorance and superstition, a similar planetary disc in the head of the with terror. The generality of comets visigreat comet of 1811; but, when that comet ble to the naked eye are tailed comets. The was examined by glasses of high power, the tail is usually developed as the comet apapp:arance of the stellar nucleus vanished. proaches the sun; and just after it has passed In 1819 a comet was observed, which exhib- that body, it for the most part appears to ited phases similar to those of a crescent attain its greatest dimensions. In some moon, during a part of the time that it was comets, the tail is an elongated train of light, visible. The nucleus of a comet which ap: becoming fainter towards the extremity; in peared in 1825, as seen by Professor Santini, others, it is rounded off, bushy, or fan-shaped. appeared to be composed of three bright Sometimes the elongated tail seems to be spots. The great comet of 1843 bad at one split at the end, so as to present the appeartime a nucleus, small, but extremely bright; ance of two or more tails. at another time it exhibited a well-defined The tail generally projects from the head planetary disc.
of the comet in a direction away from the The different appearances thus presented sun, so as to be a continuation of the line by the nuclei of different comets, and still drawn from the sun to the head of the comet. more the differences observed in the nucleus This, however, is not always the case: for in of the same comet at different times, seem the comets of 1577 and 1680 the tail devi. plainly to indicate that the nuclei of comets ated from the line joining the sun and the are not solid bodies, and that they consist of comet--that of the former 21°, and that of nebulous or gaseous matter considerably or the latter 5°. Sometimes, when comets have highly condensed.
two tails, the one is in the usual direction, Some comets are exceedingly brilliant; so and the other is towards the sun. The much so, that they have been distinctly visi- comets of 1824 and 1845 were of tbis kind ; ble during the day, and while the sun was that of 1824 had two tails, making with each sbining, and have also cast a shadow at night. other an angle which varied from 138° to This was the case with the comet mentioned | 170°; and the two tails of that of 1845 by Diodorus Siculus, and also with the one made with one another an angle of about which appeared at the birth of Mithridates, B.c. 140°. The tail of the same comet has been 134, to which we have already referred. One observed to vary greatly in appearance, and of the comets of 1618 was distinctly seen in that sometimes in the course of a single nigbt. full day light; and an instance occurred, in Occasionally a vibratory or coruscating July, 418, of a comet that had not been ob motion, something resembling certain of the served before, being detected as a brigbt motions of the aurora borealis, has been nobody in the neighborhood of the sun during ticed in the tails of some comets. The Chian eclipse. The comet of 1744 was observed nese, to whom we are indebted for a large with the telescope at noon day, and many number of careful observations of early persons could distinctly see it with the naked comets, were the first to notice these vibra. eye for a considerable period after sunrise. tions in the tail of a comet which appeared Two comets of extraordinary brightness ap- A. D. 615, and they have often been observed peared in 1402; they were seen day and since. Longomontanus described the tail of night, and caused great alarm.
ibe comet of 1618 as having “an enormous Usually the head in comets exhibits a pale, vibration;" another observer says that it aplivid, white light; sometimes it is fiery red; peared as if agitated by the wind. In the sometimes a dull red, inclining to yellow; great comet of 1843, the pulsations of the and occasionally it presents a greenish, and tail were distinctly visible. sometimes a bluish tinge. The comet of Some comets have tails not straight, but 1811 had a disc of a pale ruddy color; the sur- curved, presenting to the eye of wondering rounding nebulosity was greenish, or bluish and alarmed nations the appearance of an green. The nucleus of the comet of 1843 immense flaming sword hung out in the heavwas of a golden hue, of the color of Venus, ens. Such a phenomenon was held to poror reddish, according to different observers. tend bloody wars. The comet of 1652 was of a pale livid color. The apparent and real length of the tail The Chinese describe the comet of 1577 are generally different. If the eye of the as of a bluish color, with a white
observer be in a line drawn through the tail But it has been chiefly the tails of comets / lengthwise, the tail will seem to make a part
of the head, or, in other words, no tail will atmosphere, which is straightway driven back be distinguishable ; if the eye be a little out by some repelling power, and, passing along of the line, the tail will appear short; and it the sides of the comet, forms the tail. If is only when the eye is in a line at right an- this conjecture be correct, then the repelling gles, or nearly so, to the tail, that the whole power, whether coming from the sun, or length of it will be seen.
whencesoever it comes, must be prodigiously In some comets, the apparent length of great, for the tail generally retains a rectilinthe tail has been enormous, stretching over eal direction away from the sun, whether the 40°, 30°, 60°, and 100° of an arc of the comet be sweeping down in space towards heavens. A comet, observed in the southern that luminary, or be wbirling with lightning hemisphere in 1689, had a tail that extended speed round him in its perihelion, or nearest over 60°, and was two hours and a half in distance to him, or be receding away into rising. And we are told of the great comet space after it has passed him. which appeared in 1264, that, when its head There is considerable difficulty in finding was just above the eastern horizon, the tail the real magnitude of comets, from its being stretched away westward to beyond the mid- impossible to determine precisely where the heavens. The nearer that the comet is to the nebulous matter of which the head is comeye of the observer favorably situated, the posed terminates, inasmuch as it appears to greater will be the apparent length of the thin off from the centre, and gradually to
shade away into darkness. Besides, the But the real length of the train of light nebulous matter evidently contracts and exthat accompanies these wonderful bodies, is pands, so that the same comet has different even more confounding than its apparent dimensions at different periods. Still, the length. The tail of the celebrated comet of measurement of a number of comets ba 1680 was considerably more than 100,000,000 been accomplished, we believe, with considerof miles long; that of the comet of 1744 able accuracy. was 19,000,000 of miles ; that of the comet But, besides the contractions and expanof 1769 about 40,000,000 of miles. The sions which take place in the heads of comets great comet of 1811 had a tail of upwards from causes altogether unknown to us, there of 100,000,000 of miles in length; and the are other contractions and expansions wbich second comet of that year was accompanied some at least of these bodies undergo with by a tail 130,000,000 of miles in length;
whilst considerable regularity, and which apparently the comet of March, 1843, had a train of light depend on their approach to and departure stretching away from the nucleus, or head, from the sun. In approaching the sun they to the astonishing distance of 200,000,000 are observed to contract, in receding from of miles.
the sun they are observed to expand. This There is something in such enormous meas is certainly contrary to what we would exures of distance which the mind can hardly pect, and it is one of the many intimations grasp, that swells out our conceptions of the which we have that the physical constitution wisdom and power of Him who created and of comets--the matter of which they are rules these glorious wanderers. And in con- composed—is something of which we on nection with that wisdom and power, what earth have no experience, and can form no thoughts should we have of the first sleep of conception. the Infant in the manger of the stable at All comets, most probably, move in an elBethlehem, of the agony in the garden, of the lipse, often of very high eccentricity, although ignoming on the cross, of the humiliation and it may be that some of them, from the very helplessness in the tomb which a stranger's great velocity with which they pass their kindness supplied !
perihelion, move in a parabola, or in a hyperIn some comets there is a rim or border bola. Some comets have a direct motion in of light on the head next the sun, and pass. the order of the signs of the zodiac-i. e., in ing round on each side to form the com- the same direction as the earth and the planmencement of the tail. That border is callets; others move in a contrary or retrograde ed the envelope. Of the manner in which direction. Of the 206 comets whose orbits the envelope and tail are formed, astronomers have been calculated down to the end of 1852, can as yet do little more than conjecture. 105 have a direct, and 101 have a retroBut it is supposed that the nucleus, or more grade motion. The paths of comets are not condensed part of the head, being acted confined to the ecliptic, as those of the planupon by the sun, throws off, or outwards ets are, but comets are seen in all parts of toward the sun, a portion of the cometic the heavens-about the poles, as well as in
the zodiacal regions. They come darting friend Dr. Halley. “At Newton's suggestforth towards the sun from every quarter in ion,” says Mr. Mitchell of Cincinnati, “Halspace, and having wheeled round him with ley had searched all ancient and modern inconceivable rapidity, they rush away back records for the purpose of rescuing any hisinto those " depths profound" whence they torical details touching the appearance and emerged.
aspects of comets from the primitive ages Of the number of comets we can have no down to his own time. On the appearance certain knowledge. More than 7,000,000 of of the comet of 1682, he observed its posithese bodies, according to Arago, come with- tion with great care, and with wonderful in the orbit of Uranus. Mr. Hind
supposes pains computed the elements of its orbit. He that probably somewhat above 5,000 comets found it moving in a plane but little inclined have approached the sun within the orbit of to the ecliptic, and in an ellipse of very great Mars; of these there are trustworthy records elongation. In its apbelion it receded from of rather more than 600.
the sun 10 the enormous distance of 3,400,The discovery that comets move in an el- 000,000 of miles. He discovered that the lipse, having the sun in one of the foci, and nature of its orbit was such as to warrant the that they will
, therefore, periodically visit the belief that the comet would return at regular neighborhood of the sun, was one of surpass- intervals of about seventy-five years; and, ing interest, and the determination of the recurring
recurring to his historical table of comets, he periods of their return is one of the greatest found it possible to trace it back with certriumphs of human intellect. Let us briefly tainty several hundred years, and with probaadvert to that discovery,
bility even to the time of the birth of MithAt an early period it was thought that ridates, one hundred and thirty years before comets moved in straight lines. When this Christ." was found to be an error, and they were ob- From his computation, and from what he served to move in a curve, that curve was believed to be the historical evidence that he supposed to be a parabola, or a hyperbola. had of its former appearances, Halley boldly And indeed the parabola and byperbola dif- predicted its return in 1758 or 1759. He fer
very little from the ellipse in the small believed that before the predicted time arpart of a comet's orbit, in which it can be rived he would be in bis grave, but with that observed. For it is only for a comparatively thirst for fame which is the infirmity-shall short
space before a comet reaches its peri- we call it ?-of noble minds, and with a pahelion, and after it passes it, that it is within triotic jealousy for the honor of his native the reach of the astronomer's eye or in country, he expressed a hope that, in the struments. But it was by-and-by found that event of the comet's return, it would be rethe observations made on the orbits of differ. membered that its periodicity had been disent comets would by no means agree with covered by an Englishman. the supposition that they were moving in a As the period of the comet's return indiparabola, and plainly indicated that their or- cated by Halley approached, the calculation bit was an ellipse. The orbits of a number of the elements of its orbit was repeated of such comets have been calculated, and the with great care and labor, and under the result has been the determination of the pe- guidance of the results, astronomers in all riodical times of several comets ; and these quarters were on the out-look for the expectcalculated periodic times have been verified ed mighty traveller.
A Saxon farmer, near by the return of the comets as predicted. Dresden, of the name of Palitzch, first saw it The most celebrated are the comets known on the 25th of December, 1758. In the by the name of Halley's Encke's, and Biela's winter and spring of 1759 it was seen by comets. A brief notice of these may not be numerous observers, and it arrived at its peridevoid of interest, and may assist us in ob- helion on the 12tb of March, just a month taining a more distinct notion of the cometary before the calculated time. Even that small world.
error in these enormous calculations, and Guided by the light which his great theory affecting the passage of the comet through of gravitation threw on a variety of astronomi. an orbit of such prodigious extent, was owing cal observations, Sir Isaac Newton came to the in great part to the want, at that time, of an conclusion that the comets, like the planets, accurate knowledge of the masses of the revolve round the sun. If this bad before planets Jupiter and Saturn, whose perturbbeen suspected, it had not in any way been ing forces considerably affect the motion of proved. To verify it, if really true, became the comet. an object of deep interest to Newton, and his Halley's comet was again due in the neigh