Euphrof. Then that Part of the Heavens which was Day when the Earth was at A is now Night, and so the Stars which were all then invisible are now vifible, and the contrary.

Cleon. Very right, Sifter, that is the Cafe; and laftly, when the Earth is at D, the Stars in the Hemifphere, EFG, will be obfcured by Day-light, and thofe in G HE will all be visible in the Night.

Euphrof. Well, I am fully fatisfied in this Point, Cleonicus; but why do I fee fome Stars conftantly all the Year round, and others but at different Times and Seafons?

Cleon. You might have added too-and fome Stars not at all. But as this depends on fome Understanding of the Doctrine of the Sphere, you will apprehend it much better when I fhall one Day or other explain to you the Ufe of the Celestial Globe.

Euphrof. I am willing to wait all proper Opportunities, and am obliged to you for chufing them. And now I fuppofe there remains nothing befides relating to the Motion of the Stars to be confidered; therefore

Cleon. Hold, Sifter; before we leave this Subject, I fhall juft obferve to you, that there is only one Star in all the visible Heavens which feems to have no Motion at all.

Euphrof. Indeed! Pray, which is that?

Cleon. It is that commonly called the North Pole, or more properly the Polar Star.

Euphrof. Be fo good as to fhew it to me.

Cleon. It is that small, but bright Star, which you fee yonder, full North, amidst many other, but smaller Stars; it is ever pointed to by those two large bright Stars in Charles's Wain, which you observe a little to the Left Hand.

Euphrof. I fee the Star you mean, very plainly; and do you say it has no Motion?

Cleon. It does not appear to move either with the diurnal or annual Motion, as all the other visible Stars do but view it at what Time of the Night or Year you will, you fee it always in the fame Place.

Euphrof. But you feem to intimate by your Way of fpeaking, that it has fome fort of Motion or other ; has it not?

Cleon. It has; but fuch an one as is not fenfible in a long Course of Years, and arifes from a Caufe that you must stay a while before you can well understand it.

Euphrof. To what End then do you mention it to me, Cleonicus?

Cleon. Because there is fomething very furprifing in the Confequence thereof: For this Star, though it be now very nearly in the North Point of the World, has fuch a Motion round a certain Point in the Heavens, as will in Time make it to circulate through the several Parts of the Heavens like other Stars.

Euphrof. Say you fo; will the North Star in Time be feen Southward of us? Pray, in how long a Time?

Cleon. In the Space of twelve Thousand nine Hundred and fixty Years; for in double that Time, viz. in twentyfive Thoufand nine Hundred and twenty Years, it makes one Revolution, which is called the Great, or Platonic Year, from Plato the Philofopher, who, with other of the Antients, fuppofed that after this Period all worldly Changes would return in the fame Manner and Order as before.

Euphrof. Is this a real, or only an apparent Motion of the Stars?

Cleon. Apparent only, as are both the other. And thus much of the Motion of the Stars, of which Dryden has thefe Lines,

As when the Stars in their ethereal Race,

At Length have roll'd around the Liquid Space,
At certain Periods they refume their Place.

From the fame Point of Heav'n their Course advance,
And move in Measures of their former Dance.

}

Euphrof. I obferve a manifeft Difference in the Colour of the Stars, fome look red, others pale; pray, what can be the Meaning of that?

Cleon. You ask a Question I can't refolve.-There is somewhat undoubtedly very different in the Nature both of the Matter and Light of thofe Stars or Suns; but what that is, their Maker only knows.

Euphrof. I have had my Eye fome Time upon a Kind of brightifh mifty Spot, which at firft Glance feems like a Star; pray, is it a Star, or what is it?

Cleon. I fee what you mean; it is indeed called a nebulous, or misty Star; but it is not a Star properly fpeaking: You'll have a better Notion of it when you view it with a Telescope.

Euphrof. Give me the Tube, and I'll view it-Blefs me, what do I fee !-The Glafs is covered with Stars as thick as Bees in a Swarm.-Very fmall Stars, yet very distinct.—I do fee now what it is, indeed-A compound Star, confifting of Multitudes of fingle ones.-Well, this is a wonderful Sight, on my Word, Cleonicus.

Cleon. There is nothing more curious among the Stars, in my Opinion. There are reckoned about fix or seven of these nebulous Stars in the Heavens; in fome of which there appears a bright, lucid Part, in which fome Stars appear, as from a white Cloud, and these are reckoned to be Regions of a peculiar Nature, which enjoy a native Light, and an uninterrupted everlasting Day.

Euphrof. How infinitely various, amazing, and unaccountable are the Works of Nature! But cafting my Eyes on the feven Stars, puts me in Mind to ask a Queftion I have long intended; and that is, Why are they called the feven Stars, when no Perfon, I believe, can tell above fix?

Cleon. In Anfwer to this, I fhall at prefent only fay, that in former Times, 'tis probable, there were feven to be seen, one of which afterwards became extinct, and was never more feen; and that as long fince as Ovid's Days (who lived in the Time of our Saviour) as is evident by these Verfes in his Fafti.

Now rife the Pleiades, thofe Nymphs so fair,

Once feven number'd, now but fix there are.

Now though there appear but fix Stars in this Conftellation to the naked Eye, yet take the Telescope and view them, and you will difcover many more.

Euphrof. Pray, give it me then; I'll view them.O furprizing!-What a Number do I fee! I can tell near twenty. They fill a greater Space than the Glass will take in.-Some are very large, others fmall.-There are fo many, I can't number them all.

Cleon. I believe fo, Euphrofyne; for Dr. Hook tells us, that with a twelve Foot Tube he counted no less than 78 Stars; and making Ufe of longer Telescopes, he dif

covered

covered ftill many more. But that the Universe abounds with numberless Numbers of Stars, you will foon be convinced, by directing the Telescope to any Part of that whitish Tract of the Heavens we call the Galaxy, or Milky Way.

Euphrof. That I'll inftantly do.-I fee them, innumerable! They fill the Glafs, like the nebulous Star.If I turn the Tube this Way or that, ftill nothing but Stars are feen-Most of them very fmall, fome scarce difcernable. The Region of Heaven looks light through all this Part. Sure we have here a larger Profpect into the Universe.

Cleon. This Part of the Heavens being illuminated by the Luftre of fuch an Infinity of Stars, gave Occafion to the Heathen Poets to make it the high Road to Heaven, or to the Court of Jove. Thus Ovid;

A Way there is in Heav'n's extended Plain,
Which when the Skies are clear is feen below,
And Mortals by the Name of Milky know:
The Ground-work is of Stars, thro' which the Read
Lies open to the Thunderer's Abode.

And our famous Milton;

A broad and ample Road, whofe Duft is Gold,
And Pavement Stars, as Stars to us appear,
Seen in the Galaxy, that Milky Way,
Like to a circling Zone, powder'd with Stars.

Again; the aftronomical Poet Manilius, fpeaking of the
Galaxy, has these Lines;

Nor need we with a prying Eye furvey
The diftant Skies, to find the Milky Way,
It must be feen by all, for ev'ry Night
It forcibly intrudes upon our Sight,
And will be mark'd, for fhining Streaks adorn
The Skies as opening to let forth the Morn.
And as a beaten Path that spreads between
A trodden Meadow, and divides the Green:
Or as when Seas are plow'd, behind the Ship
Foam curls on the green Surface of the Deep;
In Heav'n's dark Surface fuch this Circle lics,
And parts with various Light the azure Skies.
Or as when Iris draws her radiant Bow,
Such feems this Circle to the World below.

It all surpriseth, our inquiring Sight

It upward draws, when thro' the Shades of Night
It fpreads its Rays, and darts amazing Light.

}

LIB. I. Euphrof. But why, Cleonicus, is this Part of the Heavens ftored with fuch Myriads of Stars more than any other Part?

Cleon. I cannot tell the Reafon, but fo it is; and hence it is that in this Part, oftener than in any other, we find the Extinction of old Stars, and the Appearance of

new ones.

Euphrof. I fhould be glad to have a fhort Account of thefe old and new Stars that you fpeak of, having never heard any Thing on that Subject.

Cleon. Hipparchus, who lived fome Years before Chrift, is faid to be the first who faw or obferved a new Star. After many Ages, in the Year 1572, a new Star appeared to Corn. Gemma, and Tycho Brahe, and became extinct in the Year 1574. It broke out with the Luftre of Venus, and decayed very gradually all the Time. Such another was feen in 1604, and died away gradually in about the fame Time. In the Year 1696, one Fabricius discovered the Stella Mira, or wonderful Star, in the Neck of the Whale, which is found to appear and difappear periodically, its Period being feven Revolutions in fix Years. In the Year 1600, Wm. Fanfonius difcovered another in the Neck of the Swan, which has fince appeared of different Magnitudes, and is now very small. Another was discovered in the Year 1670, by Hevelius, and difappeared in 1672. And in the Year 1686, the last new Star was difcovered by Mr. G. Kirch, which returns periodically in the Space of about 404 Days; and these are all the fixed Stars which have altered-their Appearance for 160 Years past.

Euphrof. Dear Cleonicus, I am obliged to you; but fear I tire you with my Impertinencies: 'Tis late, and I'll have done, if you'll only tell me what I am to underftand by the Star which I faw this Moment shoot along a good Part of the Heavens.

Cleon. It was not a Star that you faw, my Euphrofyne, but only a fiery Meteor kindled in the Air, and then looked like a Star; and as all fuch Bodies move swiftly VOL, I.

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