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ther Obfervations confirm this Parallax, and any fort of Equality thereof, we must accommodate our Opinions to our Evidence, and in that Cafe muft fuppofe, that the grand System themfelves of Sun, Planets. Comets, and Fixed Stars are, like the Parts of fuch a Syftem, vaftly remote from each other; nay, perhaps, out of the reach of each others Discovery alfo. But as to this noble Theory, we cannot be at all pofitive till the Parallax and Distance of the Fixed Stars be more nicely obferv'd, and the Aftronomical World better fatisfy'd about it; the doing of which I would therefore earnestly recommend to the publick Confideration.

(18.) Several of these Fixed Stars, especially of the smaller fort, do fometimes disappear, and new ones appear; and fome of them do appear or disappear, look Brighter or Duller by Turns; and this fometimes after certain Intervals of Time alfo. This is a known Fact; and has in fome measure been noted from almoft the earliest Ages of Aftronomy. But then, what should be the Caufe of fuch mutable Appearances among these Fixed Stars, is by no means yet discovered; nor have I hitherto ventur'd to propofe any ConjeЄture about them. However, fince others have alteady begun their Hypothefes, which feem to me commonly either entirely precarious or abfolutely impoffible, I fhall make bold here to offer my own, which shall not only be free from fuch strong Objections, but agreeable to the nearest parallel Cafe in the World. We know that the Sun it felf, the only Fixed Star, as I may call it, that is fufficiently within the reach of our Telescopes, has feveral Times not a few Maculæ or Spots upon his Body; which fre

quently

quently become Facula, or Parts brighter than the reft; and which come and go by turns. How many there may poffibly be of thefe Spots at certain times we cannot fay; but this is plain, that we do not know but fo many of them may fometimes arife, as may, in good part, cover over the Sun's Surface, and render its Light and Heat very Weak and Dull. Thefe Spots may be again diffipated, and become Facula, or Brighter than ordinary. Thefe Macule and Facule may fometimes, by Turns, gain ground on one another, after certain Intervals of Time, and cause the Sun to grow Darker and Brighter periodically. Nay, we do not know, but thefe Macule may fometimes, efpecially in Cafe the Sun were fmaller, cover over the greatest Part of its Surface, fo as to extinguifh, or at leaft to obfcure its Light; which yet in Length of Time may be overcome, and the Sun may recover its former Splendor, if not one greater than that before. Since therefore fuch Phænomena of the Fixed Stars are like what our Sun appears by known Obfervations to be in fome fort liable to, I think it the best Guide, as to what we fee to happen to others of them; and that the Macule and Facule of thofe Stars may caufe thefe furprizing Appearances. Nor can I easily think in any other manner, about thofe fix Spaces of Light, or Starry Mists, which have been lately difcovered in the Heavens, than by Analogy to what we know of Things of a like Nature; viz. that they are a Company of Tranfact. very fmall Fixed Stars, as invifible to us with Philof. N. our ordinary Telefcopes, as the known Telefco347 for pick Stars in the Milky Way are to our natural A.D.1706. Eyes, which give fuch an irregular Appearance of indiftinct Light alfo. PART

PART IV.

Certain Obfervations drawn from the foregoing Syftem.

(1.)

S

INCE Matter is entirely a Paffive Substance; no fpontaneous Motion or Action, even in Brutes, can be derived from it; much lefs can that Active and Free Being, the Soul of Man, be justly suppofed to be material.

(2.) Since Bodies once exifting will continue to exist, and that for ever, in the fame State of Rest, or uniform Motion, along strait Lines, wherein they once are; at least with the alone Concurrence of the First Caufe; the Projectile Motions of the Heavenly Bodies require no new, or particular conftant Acts of Power for their continuation in that State. But,

(3.) Since none of the Heavenly Bodies move uniformly in ftrait Lines, but all of them rather unequally, and all in Curves, they are every one impell'd, and that perpetually, .by fome External Power, Efficacy, Force, or Influence; and G thereby

thereby are obliged to revolve in fuch Curves; which Power we have already proved to be that of Gravity,

(4.) If that Power of Gravity were fufpended, all the whole Syftem would immediately diffolve; and each of the Heavenly Bodies would be crumbled into Duft; the single Atoms commencing their feveral Motions in such several ftrait Lines, according to which the projectile Motion chanc'd to be at the Inftant when that Influence was fufpended or withdrawn.

(5.) Since pendulous Bodies receive no fenfible Resistance in their Internal Parts; and fince both the Planets and Comets move prodigiously fwift, with the utmoft Freedom, and without any fenfible Refistance through the Æthereal Regions, 'tis certain there is no Subtile Matter pervading the Univerfe, as fome have fuppofed.

(6.) All the Solutions, therefore, of the Phanomena of Nature, which depend on the Suppofition of that Subtile Matter, are entirely false, and contrary to the plain State of our Syftem.

(7.) To fuppofe a Plenum, or that the Univerfe is entirely full of fuch Subtile Matter, is utterly vain and ungrounded; nay, contrary to the most certain Obfervations.

(8.) Since the particular Proportion ever obtaining as to the Power of Gravity, I mean that of the Duplicate of the Nearness of Bodies, is not any neceffary Refult from the Nature of Matter, or any Laws of Motion in the World; it is plain that this Proportion is no way owing to any Mechanical Caufe or Neceffity whatfoever, but entirely to free Choice, Prudence and Judgment. (9.) Since

(9.) Since all Bodies are equally capable of Reft, and of all Degrees of Velocity whatfoever; but are in their own Nature no way determin'd to any of them; that nice Adjustment there is of the projectile Velocity to the Attractive Power through the whole Universe; whereby the Planets both primary and fecondary revolve nearly in Circles, and the Comets nearly in Parabola's, is no way owing to any Mechanical Caufe, or Neceffity whatsoever; but entirely to free Choice, Prudence, and Judg

ment.

(10.) Since all Bodies are equally capable of being originally impell'd every way, and of having their projectile Motions in any Direction whatsoever; and fince all the Planets, both Primary and Secondary, have their projectile Motions almoft perpendicular to the Lines from their Central Bodies, which was abfolutely neceffary to their Motion at nearly the fame Di-, ftance from the Sun; this nice Adjuftment of the Direction of their projectile Velocity, whereby they became fit for the Habitation of Animals, and without which they would have been almost useless in the World, is no way owing to any Mechanical Caufe, or Neceffity whatfoever; but entirely to free Choice, Prudence, and Judgment.

(11.) Since all Bodies are equally capable of Reft as of Motion, and that in any Time, and with any Velocity; and fince there is no original Connection between the projectile Directi ons and Velocities, of any two or more Bodies which now revolve about the common Centers of their own Gravities; without which Revolutions about thofe Centers, the prefent System of the G 2 Univerfe

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