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the dreariness of the remote situation of the planet, and of the intensity of the cold, he says,

Yet even here the sight,

Amid these doleful scenes, new matter finds
Of wonder and delight! a mighty ring,

On each side rising from the horizon's verge,
Self-poised in air, with its bright circle round
Encompasseth his orb.

MALLET.

The planet Saturn is surrounded with no fewer than seven satellites, which supply him with light during the absence of the Sun; but of these we shall speak hereafter.

The Georgium Sidus, called also the Herschel planet, is, as far as has been discovered, the outermost body of our system. It is too far distant from the earth to admit of very accurate observation, though it has sometimes been seen by the naked eye. The lines which Mallet applied to Saturn are now, with a little change, more applicable to the Georgium Sidus or Herschel planet.

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Last, outmost Herschel walks his frontier round,

The boundary of worlds; with his pale moons,

Faint-glimmering thro' the darkness night has thrown, Deep dyed and dead, o'er this chill globe forlorn:

An endless desart, where extreme of cold

Eternal sits, as in his native scat,

On wintry hills of never-thawing ice;
Such Herschel's earth.

This new planet is denominated by foreign astronomers the Uranus, as well as the Herschel. Though discovered by Dr. Herschel, as a planet, it had been observed by Flamstead, Mayer, and others, and put down in their catalogues of fixed stars. It is situated at the distance of 1,800,000 miles from the sun, and performs its annual journey round that luminary in little more than 83 of our years. Its diameter is 35,112 miles, or about 4} times larger than that of the earth; of course the

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disk of our planet being 20 times less to the inhabitants of the Herschel than he is to us, it must be wholly invisible to them without the aid of powerful glasses. How mortifying to the pride of man, that the planet upon which he lives is so insignificant as not even to be known to exist by other inhabitants of the system of which it is a part! When seen by the naked eye, it appears like a fixed star of the sixth magnitude, with a blueish white light, and a brilliancy between that of Venus and the moon.

Besides the primary planets here mentioned, there are eighteen others, called secondary planets, or satellites, which regard their primaries as the centres of their motions, and revolve round them in the same manner as those primaries do round the sun.

One of the most conspicuous of these satellites is the moon, which is a constant attendant on the earth; and, while she accompanies it in its annual progress through the heavens, keeps revolving round it continually, by a different motion, in the space of a month. The diameter of the moon is 2180, her distance from the earth 240,000 miles; and in bulk she is sixty times less than the earth. Jupiter has four such moons, Saturn seven, and the Georgian six: and from the continual change of their phases or appearances, it is evident that these also are opaque bodies, like the planets, and shine only by the means of the borrowed light which they receive from the sun.

It may be observed, also, that our earth is a moon to the moon, waxing and waning in exactly the same manner, but appearing about thirteen times larger, and, of course, affording a proportional quantity of light. When she changes on us, the earth will appear full to her; and when

she is in her first quarter to us, the earth will be in its third quarter to her. And as her axis is almost perpendicular to the plane of the ecliptic, one half of her orb will be constantly illuminated by the reflected light afforded by the earth in the sun's absence, and the other will have a fortnight's light, and a fortnight's darkness alternately.The rotation of the moon round the earth is also performed exactly in the same time that she goesonce round the earth, as is evident from her always presenting the same face to us during the whole of her monthly revolution; and, on this account, it is plain, that the inhabitants of one half of the lunar world are totally deprived of a sight of the earth, and must for ever remain ignorant of its existence, unless business or pleasure lead them to explore the opposite hemisphere; where they may have a full view of our globe, moving majestically through the heavens, and appearing to them like a newly-created planet, of a magnitude nearly thirteen times larger than that of the sun'.

Comets are now the only objects in our system that remain to be mentioned; but the consideration of these, and of the infinity of stars that cover the whole face of the heavens, I reserve for my succeeding paper, and conclude this in the beautiful language of Thomson:

With what an awful world-revolving power
Were first the unwieldy planets launched along
The illimitable void! There to remain,

Amid the flux of many thousand years,

That oft have swept the toiling race of men,

See various other particulars concerning the moon în No. XXII. For a full account of the Solar System, with the recent discoveries of Dr. Herschel, we refer to Time's Telescope for 1814, and also to the subsequent volumes for 1815, 1816, and 1817, for a History of Astronomy, and other interesting matter on this subject.

And all their laboured monuments away.
Firm, unremitting, matchless in their course,
To the kind tempered change of night and day,
And of the seasons ever stealing round,

Minutely faithful: such the All-perfect Hand,
That poised, impels, and rules the steady wholes

No. VIII.

ON COMETS.

Hast thou ne'er seen the comet's flaming flight?
Th' illustrious stranger passing, terror sheds
On gazing nations, from his fiery traiu

Of length enormous; takes his ample round

Through depths of ether; coasts unnumbered worlds
Of more than solar glory; doubles wide
Heaven's mighty cape, and then revisits earth,
From the long travel of a thousand years.

YOUNG.

THE astronomy of comets may be properly said to be yet in its infancy, no advances having been made in it before the seventeenth century. With respect to the antients, they knew very little of their nature or motions. Some considered them as wandering stars; others supposed them to be mere appearances, formed either by reflections or refractions of the Sun's beams, having no real or distinct substance from other celestial bodies. Others believed them to be fiery meteors, generated of bituminous exhalations from our terraqueous globe, which, being elevated to the higher regions of the atmosphere, were there set on fire, and continued their appearance till all their sulphureous particles were consumed; while others considered them only as ominous phenomena, displayed by the

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Supreme Being to terrify mankind, and warn them of the approach of some dreadful calamity. And the same opinion prevailed during the dark ages between the decline of the Roman empire and the Reformation.

The poets have frequently compared a hero in his shining armour to a comet; and as poetry delights in omens, prodigies, and such wonderful events as were supposed to follow upon the appearance of comets, eclipses, and the like, they never fail to make some allusion to the popular superstition on this subject. Thus Homer, Virgil, and Tasso, who have been copied by Milton, in his fine comparison of Satan to a comet:

Incensed with indignation, Satan stood
Unterrified, and like a comet burned,
That fires the length of Ophiucus huge
In the arctic sky, and from his horrid hair
Shakes pestilence and war.

Milton has here exceeded his originals in sublimity; and his comparison is applied with much greater propriety than theirs; for they describe only a mortal hero, but Milton is speaking of a superhuman being.-I shall give two more quotations, in which, I think, the popular opinion is not only poetically but philosophically mentioned: In fancy's eye encount'ring armies glare, And sanguine ensigns wave unfurled in air! Hence the deep vulgar deem impending fate, A monarca uined or unpeopled state. Thus comets, dreadful visitants! arise, To them wild omens, science to the wise! These mark the comet to the Sun incline, While deep-red flames around its centre shine! While its fierce rear a winding trail displays, And lights all ether with the sweeping blaze!

The aurora borealis: for an account of the remarkable appearances of this meteor, see No. LI.

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