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Astronomers conjecture, not without reason, from the analogies of our own system, that these suns do not revolve round each other shedding their light in vain; but that each is accompanied by its circle of planets, which, being opaque bodies, would of course be for ever shrouded from our view by the splendour of their respective orbs of day. This idea leads us to conclude that the stars, which are separated from each other by distances at least as great as that of Uranus from our sun-that is to say, some eighteen hundred millions of miles-have also their respective planets, their Mercuries, their Earths, their Jupiters and Saturns, and are the centres of peculiar systems throughout the whole firmament. If those planets be peopled by intelligent beings, as Earth is, and the other planets of our solar region are supposed to be, the contemplation in thought of such myriads of globes with their inhabitants overwhelms the mind.

We have no mode of ascertaining the distance of any one of the stars from the earth. We have measured the circumference which we describe in our annual journey round the sun; we take the diameter of that circle, and with it form the base of a triangle whose vertex should be at the nearest of those luminous bodies. The angle thus formed, however, at the star, would be unappreciable with the most perfect instrument of human invention. Now an angle of one second of a degree is appreciable; consequently the distance of the nearest fixed star must exceed the radius of a circle, one second of whose circumference measures one hundred and ninety millions of miles; that is, it must exceed two hundred thousand times the diameter of the earth's orbit. If the dove, that returned no more to Noah, had been commissioned to bear, with her utmost speed, an olive branch to the least remote of the spheres, she would, therefore, still be on her journey:-after towering for forty centuries through the heights of space, she would not at this moment have reached even the middle of her destined way.

No machinery has yet been invented, indeed it seems at present impossible that we should ever devise any means, by which we might

* The double star y in the foot of Andromeda, we observed, under favourable circumstances, on the evening of the 30th of July last. It is among the most beautiful objects in the heavens. One of these stars is considerably larger than the other, and of a reddish white light. The colour of the smaller star is of a fine bright sky blue, inclining to green. Seen through a telescope of inferior power, they appear like companion butterflies fluttering in the sky; in one of medium power they become welldefined objects. Sir W. Herschel says, that the striking difference in the colour of the two stars suggests the idea of a sun and its planet, to which the contrast of their unequal size contributes not a little.' With all due deference to his authority, we must say, that we cannot understand how one self-luminous body can be the attendant of another. A straight line drawn downward through the two brightest stars of Cassiopeia, and extended to something more than twice their distance from each other, will strike the double star in question.

estimate

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estimate the magnitude of even the least of the stars, since we never behold their discs. We become sensible of their existence by rays of light, which must have taken, in some instances, probably, a thousand years to reach our globe, although light is known to travel at the rate of one hundred and ninety-two thousand miles in a second. Sirius, the brightest, because perhaps the nearest to us of those luminaries, is conjectured by Dr. Wollaston to give as much light as fourteen suns, each as large as ours. Magnificent, therefore, as the system must be of which Sirius forms the centres yet we behold no part of it. The planet Saturn, with its appendages of rings and satellites, exhibits, when its rings are visible, a spectacle, which seen through a telescope of moderate power, we imagine that a half-crown piece would cover.* an individual gazing through a similar instrument from a planet of Sirius at our sun, might suppose, in the same manner, that he could cover our entire system with a spider's thread. He would set down the sun in his map as a fixed star; but to his eye it would present no variation, as the largest of our planets would not intercept much more than a hundredth part of the sun's surface, and could not therefore produce any loss of its light of which he could take an estimate. For him this globe of ours, immense as to our finite faculties it seems to be, would have actually no existence. It would find not even a point's place on his chart, and if it were blotted out of space to-morrow, it would never be missed by any of the probably fifty worlds that are bathed in the floods of light which Sirius pours forth. Whose eye is it that watches over our sphere? Whose is the ever-extended arm that maintains it?

The star called Omicron, in the constellation Cetus, appears to us only twelve times in eleven years. It is seen in its greatest brightness during a fortnight; it then decreases gradually during three months, when it disappears. After an interval of five months it again becomes visible, and continues increasing during the three remaining months of its period. Another star, that called Algol, or B Persei, continues visible during a period of sixty-two hours, when it suddenly loses its splendour, and, though a star of the second magnitude, becomes reduced to the fourth magnitude in the course of two or three hours. It then begins to increase again, and in three hours and a half it resumes its wonted lustre. Goodricke, who discovered this remarkable fact in 1782, suggests,

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* The rings have been gradually opening since the 13th of June. In 1839 they will afford as magnificent a spectacle as they did in 1825.

+ The same discovery appears to have been made nearly about the same time by Palitzch, a farmer of Prolitz near Dresden-a peasant by station, an astronomer by

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and his idea is now generally adopted by astronomers, that this variation must be caused by the revolution around Algol, of some opaque body, a planet of its own, which, when interposed between us and the star, cuts off a large portion of its light. It is highly probable that a similar arrangement periodically affects the light of Omicron, though upon a different scale. There are eleven other stars that exhibit analogous phenomena, some of them at intervals of five hundred years, to which we may look forward without danger of mistake-thus opening a vista of futurity. When we reflect upon these facts-and upou the circumstance that the rays, by which we may to-night behold the Pleiads, must have left their sources in the time of our Heptarchy, or before it -we feel that the mind which is in this manner enabled to comprehend the existence of myriads of peopled worlds besides our own, and to glance to the future and the past with more than the speed of light itself, must be the creation of some superior Spirit dwelling in eternity.

Placed as we are, according to the opinion of astronomers, in the middle of the strata of systems which animate all space, and favoured though we be by supernatural disclosures and by great scientific acquirements, we are nevertheless prone to question whether such systems exist of their own innate vigour, or whether they have been created by a power extrinsic to themselves. If they are discovered to be self-existent, it follows that they must be imperishable. But if they are proved to be perishable, it follows that they cannot be self-existent, and then they must have been created by an extrinsic power, which power must be Omnipotent from the very nature of its productions. The same power must be self-existent therefore, since no agency inferior to Omnipotence could have given such a Being birth; and it must be Eternal, as an Omnipotent, Self-existent Being can know neither infancy nor age. Here then, upon an inquiry of the greatest importance to mankind, astronomical facts come to our assistance, which carry with them a force of conviction as strong as any demonstration in mathematics-and stronger than most of the evidence upon which the history of human transactions is founded. The stamp of mortality, the finger of death itself, has been traced upon some of the brightest worlds which have ever yet been seen in the firmament.

nature-who, from his familiar acquaintance with the aspect of the heavens, had been led to notice, among so many thousand stars, this one, as distinguished from the rest by its variation, and had ascertained its period. The same Palitzch was also the first to rediscover the predicted comet of Halley, in 1759, which he saw nearly a month before any of the astronomers, who, armed with their telescopes, were anxiously watching its return. These anecdotes bring us back to the age of the Chaldean shepherds.'-Sir John Herschel's Treatise on Astronomy, p. 381. n.

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In the year 125 B.C., an extraordinary luminary attracted the attention of Hipparchus, which induced him to frame a catalogue of stars, the earliest on record. That star disappeared in his time from the heavens. In A.D. 389, a star blazed forth near a Aquila, remained three weeks as bright as Venus, and then died away. In the year 1572, Tycho Brahe, returning home one evening from his observatory to his dwelling-house was surprised to find a group of people looking in astonishment at a bright star, which he with all his scrutiny of the heavens had never seen before It shone in the constellation Cassiopeia, was then as bright as Sirius, and for a while was visible even at mid-day. It began to fade in December of the same year, and after exhibiting all the changes of conflagration, disappeared in March, 1574. War this a satellite of some fixed star which caught fire, and thus prefigured to us the fate, that, according to the declarations of the prophets, awaits our own world ?

Similar phenomena,' says Sir John Herschel, though of a less splendid character, have taken place more recently, as in the case of the star of the third magnitude discovered in 1670, by Anthelm, in the head of the Swan; which, after becoming completely invisible, reappeared, and after undergoing one or two singular fluctuations of light, during two years, at last died away entirely, and has not since been seen. On a careful re-examination of the heavens, too, and a comparison of catalogues, many stars are now found to be missing; and although there is no doubt that these losses have often arisen from mistaken entries, yet, in many instances, it is equally certain that there is no mistake in the observation or entry, and that the star has really been observed, and as really has disappeared from the heavens.' -Treatise on Astronomy, p. 384.

The existence and death of Alexander the Great,-the rise and fall of the Roman empire,-the destruction, by earthquake or volcano, of cities, which were once the seats of commerce and the arts -have been handed down to us upon evidence, in no respect whatever better entitled to our belief, than that upon which the astronomical facts here related by Sir John Herschel stand recorded. Men who have made it their peculiar occupation for years.

The work from which we quote is Sir John's Treatise on Astronomy, which forms one of the numbers of Dr. Lardner's Cabinet Cyclopædia. We recommend it to the attention of everybody who wishes to become acquainted with the sublime truths of astronomy, without having his mind harassed by the technical details which render almost all other works of the kind repulsive to the general reader. But before he enters upon that treatise, he should prepare his thoughts for the tone of elevation which it requires, by reading Mrs. Somerville's delightful volume on the Connexion of the Physical Sciences. The style of this astonishing production is so clear and unaffected, and conveys, with so much simplicity, so great a mass of profound knowledge, that it should be placed in the hands of every youth, the moment he has mastered the general rudiments of education.

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to observe the changes in the firmament, agree in stating that, in many instances, stars, which were once familiar to the eye, have ceased to appear, and that, too, for periods which clearly indicate their annihilation. The consequence is obvious and inevitable-those bodies must have been created, otherwise they could not have been liable to decay.* They performed their appointed revolutions, and they perished-just as man lives his predestined number of years, and dies. If created, then there must be some power which gave them existence, and prescribed the laws by which that existence was carried to its close.

We know it will be said, that these, after all, are but the records of astronomy, a science which deals with objects that cannot be subjected to the touch, or compelled to go through the ordeal of experiment-objects of a magnitude that cannot be measured, placed at distances from us that never can be ascertained. It will be admitted, however, by any person who looks into the Almanac, that eclipses of the sun and moon are calculated beforehand to the moment. We have now, for instance, before us a list of eclipses for the whole of the present century; and until some one of these calculations shall turn out to be erroneous, it must be conceded that astronomy has its certainties as well as chemistry or mathematics. But more than even this can be said for the pursuits of a Kepler and a Herschel. The former was enabled by his acquaintance, even in the sixteenth century, with the mechanism of the heavens, to lay down a series of laws, from which it was subsequently inferred as a strong probability, that a planet, which had then been never seen by human eye, would be discovered in a particular region of the firmament; and this prediction was veritied. Kepler showed that the planets then known,-viz., Mercury, Venus, Earth, Mars, Jupiter, and Saturn, to which Sir W. Herschel added Uranus in 1781,— were all, as it were, of one family, 'bound up in one chain-interwoven in one web of mutual relation and harmonious agreement -subjected to one pervading influence, which extends from the centre to the farthest limits of that great system, of which all of them, the earth included, must henceforth be regarded as members. Now as the intervals between the planetary orbits go on doubling, or nearly so, in proportion as they recede from the sun, and the much greater interval between Mars and Jupiter would

* We forget whence we extracted the following quaint but expressive lines:— "Quench'd volcanoes, rifted mountains,

Oceans driven from land,

Isles submerged and dried up fountains,
Empires-whelmed in sand :-

What?-though her doom be yet untold-
Nature like time is waxing old.'

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