Way about the Sun (according to Copernicus) made fome Alteration of Sight with respect to the fix'd Stars, in Proportion as the Earth was fo much nearer, or fo much farther from them ; whereby likewife the Syftem of Copernicus of the Earth's Motion, feemed to be proved at the fame time. I fhall not here rehearse the differing Notions of Gregory, Whiston, and others, about the fame; but that from thefe Obfervations, even tho' they were true, the Distance of the Stars and Motion of the Earth cannot be proved, is fufficiently fhewn by Mr. Caffini, in the Hiftory of the French Academy for the Year 1699.

So that these two laft Methods, in which all imaginable Helps, known to the Moderns, are used, leaving the Matter ftill uncertain, there is no great Hopes of meeting any better, at least fince the Globe of the Earth is no bigger, or (according to Copernicus) its Way about the Sun of a larger, that it may the better ferve for a Foundation for fuch an Admeasurement. Now as long as the Distance of the fix'd Stars from the Sun or from the Earth remains unmeafurable, it follows from thence, that the Magnitude of the Starry Heavens, tho' one were to confider it as an Orb about the Sun or Earth, which cannor yet be proved from Nature, will always remain likewife immenfurable.

SECT. LI. Whether the Starry Firmament be Solid or Fluid:

Now fince fuch great Mathematicians have with fo much Ingenuity owned themselves unable to measure the fo vastly extended Magnitude of the Starry Heavens, which does in a manner furpass all human Imagination, how great Progrefs had there been perhaps made in the Science of

Nature,

Nature, if the Philofophers had behaved after the fame manner, with respect to the Matter and Figure of which this Starry Heaven consists, and if they had made the best use of that Time which young Learners employ in uncertain Conjectures and Hypothefes, without any Foundation, in making new and material Obfervations? Since it remains a Mystery to the greatest Aftronomers, how the heavenly Bodies are framed and conftituted. Defcartes fuppofes 'em to confift of fluid Vortices, as is well known. Sir Ifaac Newton, in his Scholium to the 53 Propofition in the Third Book, fhews the contrary; and farther, fubjoins, that this Hypothefis is inconfiftent with all Aftrono mical Appearances; concerning which Mr. Huy gens may likewife be confulted in his Cofmotheores, from p. 139 quite to the end, and in other Places; not to mention any more.

SECT. LIL Probable. Reafons for its being Solid,

THE Foundation of these Opinions, that the Heavens are a folid Body, is principally, That the distance of the Stars from each other has remain'd in a manner the fame without any Alteration for fo many Ages, which feems more agreeable to the Nature of a folid Matter, in which they are fuppofed to be placed, than in a Fluid.

THIS Conclufion feems likewife to be made with some kind of Probability, from the wonderful Obfervation related by Mr. Huygens in his Syft. Saturn. p. 8 and 9, and which we don't know to have been taken notice of by any one before: His Words are as follows: " Aftronomers place "three Stars close to each other in the Sword "of Orion; and when I view'd the middlemoft "with a Telescope, in the Year 1656, there ap❝peared in the Place of that one (which is no

"new

σε new thing) twelve other Stars, after the manec ner as they are reprefented in Tab. XXIII. Fig. 1. Among thefe, three that do almost touch "each other, and four more befides, appeared "twinkling as thro' a Fogg; fo that the Space "about 'em seemed much brighter and lighter " than the rest of the Heavens, which appearing wholly blackish, by reafon of the fair Weather, was feen as through a certain Opening and Se"paration, thro' which one had a free View into "another Region that was more enlighten'd. I "have often obferved the very fame thing with this "without any Alteration, and in the fame Place; "fo that it is likely that this Wonder, whatever "it may be in itself, has been there from all "Times; but I never took notice of any thing "like it among the reft of the fix'd Stars; for we "do not find that the others, which were for"merly accounted cloudy (Nebulofa) nor the

Milky-Way itfelf, have any Mift or Vapour "about 'em; nor if we view them with a Tele"fcope do they appear to be any thing else than a Collection of many fmall Stars.

each

Now I leave it to the Judgment of an impartial Perfon, whether one has not more Reafon from these Experiments, to believe, that the ftarry Heavens do rather confist of a solid Matter, than a Flood of Particles continually moving among other; fince the aforefaid enlighten'd Opening fhews itfelf circumfcribed, after the fame manner, which in fluid Matters, that are so fufceptible of Motion, can hardly be expected.

SECT. LIII. The amazing Greatness and Distance of the Stars.

Now to proceed: As this great visible Fir mament is immenfurable, on account of the almoft inconceivable Extent of the Distance thereof, so likewise must we look upon the Remotenefs of the Stars, and the Magnitude of those Bodies, as things uncapable of being determined by Men: The Reason is, because the Diameter of the Earth is to that of a fixed Star, As the Horizontal Paralax To the apparent Diameter of the fame. Now it is plain by Experience, that the Earth, and even according to Copernicus, the Diameter of that whole Circle, which it makes about the Sun, must be confider'd only as a Point, with respect to the Distance of the Stars; and much too fmall to produce any Parallax. Befides, we likewife find, that the best Telescopes that are made, can only represent the faid Stars as fo many Points of Needles, and without Breadth, infomuch that we can't discover any Measure of the apparent Diameters thereof by the Help of thofe Inftruments; fo that from the Impoffibility of obferving the Parallax, and efpecially the apparent Diameter, we are entirely difabled from determining the Magnitude of thofe Stars.

Now whether, with the modern Aftronomers, we are to confider every one of thofe Stars, at least all those of the first Magnitude, fuch as the Dog-Star, and the like, as fo many Suns, both in Splendor and Bignefs, has not yet been proved by any one: This is certain, that they are immea furably remote from us, and that in fo unconceivable a Distance they derive a native Light down to us; as alfo, that if the Sun were as far from us, Vot: III. Ddd

it would not appear bigger than one of those Stars.

If therefore, without infifting upon a real Proof, we fuppofe thofe Stars to be fo many Suns from the Strength of their Light, and from their great Distance (in which we do but follow, if not all, at least the greateft Aftronomers) we fhall have an Idea of the Heavenly Bodies that includes in it an amazing Greatness.

According to this manner, the Conjectures of Mr. Huygens will not appear ill grounded, who, upon the Calculation laid down in his Cof motheoros, p. 136, and 137. makes the Distance of the fix'd Stars from the Earth 27,664 times greater than that of the Sun. So that if, according to what we have faid before, a Cannon-Bullet will require 26 Years in paffing from hence to the Sun, with the fame Velocity wherewith it was discharged, it would require, in order to arrive at the fix'd Stars, 25 times 27,664, that is, 691,600, or almost Seven hundred thoufand Years; and a Ship that can fail 50 Miles in a Day and a Night, will require 30,430,400 Years. And if we proceed farther upon this fame Foun dation, and fuppofe, with thofe Gentlemen, that each Star has a Space about it proportionable to that of the Sun, I leave every Man to judge, whether he be able, without a great deal of Pains, to form to himself a just Idea of this wonderful Extent of the Univerfe, and whether he be not in danger of lofing himfelf in the Contemplation of fo unconceivable a Greatnefs of fo glorious a Structure, in which the Footsteps of the Divine Builder do fo manifeftly appear. I have chofe rather to make use of this Hypothefis of Mr. Huygens, preferrable to others, because nothing elfe is laid down by the fame, than that one

of