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Show dbs SU SU SU i Light is the actual] Burning orFireof its fuperficial Parts. Nor can there be any Objeétion of Moment brought againft this Hypothefis, from the Danger of the Sun’s Fire being burnt quite out in fo many thoufand Years as it hath been in Being ; for (fays he) fuppofing it to have grown fome Minutes lefs, finceit beganto give Light, none can contradi& it by any Obfervations we have upon Record. For fuppofing we had Aftronomical Obfervations of 4000 Years ftanding, as we have none above 2000 of that kind; and allowing that the Sun’s Diameter had then been obferv’d to be as many Minutesas it is now; yet it could not thence be concluded, that the Sui did not lofé a Mile in Diameter every Year, and confequently be now 4000 Miles lefs in Di: meter thanit then was. Forfince his Diameter is near 84 times greater than that of the Earth, whichlatter he fuppofes 8000 Miles, then the Sun’s mut be 696000 Miles, Now4000 is but 174th Part of the Diameter, and confequently would have diminifh’d it but tof a Minute, which is a much lef Quantity than the Antients pretended to obferve to. But fuppofing theycould have obferv’d even to Seconds, yet that could not have contra- dicted it, becaufe it is poffible the Sun may approached as much nearer us as that Diminution amounts to, and for which, he faith, he could fhew a Reafon. Sir I/aac Ne alfo in his Opticks, giv n to fuppofe the Suz and fi o be great Earths, vehemently hot ; e Heat is conferv’d by the Greatnef$ of their Bodies ; and the mutual Aétion and Re- action between them and the Licht which they emit, and whofe Parts are t from fuming av not onlyby their Fis ty, but alfo 5 Weight and Denfity of the Atmofpheres incumbent on them, and every way ftrongly compreffing them, and condenfing the Vapours and Exhalations which arife from them. The Light feems to be emitted from the Sun and fix’d Stars (which probably are Suns to other Syftems) much after the manner as Iron, whenheated to fuch a Degree, as to be juft going into Fufion by the vibrating Motion of its Parts, emits with Force and Violence copious Streams of liquid Fire all around : Great Bodies mutt preferve their Heat longeft, and that, perhaps, in the Proportion oftheir Diameters. Sir [/aacNewton hath made it probable, that the great Comet in the Year 1680, inits Peribelion, went fo near the Sun, as that it acquired a Heat, which would not intirely go off in $0,000 Years: Whence We mayguefs, that ifthe Suu and fix’d Stars be only Collections of denfe and folid Matter, like the but heated to a very intenfe Degree, Planets, be manyMillions of Years without they may Jofing any confiderable Part of their Heat. According to Caffini, the Sun’s Diftance from the Earth is 172,800,000 Englifb Miles, BR As for the annual Motion of the Sun yo the Earth ; it is cafj ly fhewn by Aftronomer that the annual Motion of the Earth will occafion fuch an Appearance. A Spectatorin the Sun would fee the Earth move from Wep to Eaft, for the fame Reafon that we fee’ the Sun move from £. aft to Wes and all the Phenomena retulting from this annual Motion in which foeverof the Bodiesit be, will appear, the fame fromeither. As to the Nature, Properties and Figure of the Sun, &c. 1. As the folar Spots are found fometi mes to itay three Days longer behind the Sun than they {pend in paffing over the Her {phere vifible to us ; we eafily deduce, that they don’t adhere to the Surface ofthe Sui, but are at fome Diftance therefrom. 2, As the Spots frequently rife, and vanith, even in the Midft ofthe Sun’s Disk, and undergo feveral Changes, both with regard to Bulk, Figure, and Denfity, it follows, thar they frequentlyrife, de nove, about the Sun, and are again diffipated. 3. Hence it fhould follow, that they are form’d out of the Exhalations of the Su», and are no other than folar Clouds. 4. Since then Exhalations proceeding from the Suu, rife above him, and ftop at acertain Altitude ; it is evident, there is fome Fluid encompafling the Sun, to urge the Exhalations to rife; and this Fluid muft be denfer at Bottom, and rarer at Top, like our Atmo{phere, §. Since the Spots frequently diffolve and difappear in the Middle of the Sun’s Disk ; the Matter of the Spots, that is, the Solar Exhalations, fall back againtothe Suz: Whence it follows, that there muft arife various Altefations in the Swx’s Atmofphere, and the Sua himfelf. 6. Since the Revolution of the Spots round the Sum is found very reg ar, and likewile very near the Suz; it follows, that they do not revolve round the Suz, but that the Sill together with his Atmofphere, wherein the Macule are, move round their common A in an Interval of about twenty-feven Da and henceit is, that the Spots near the Lim being view’d obliquely, 2 appear narrow and long. 7. Since the Sum in everySitu like a circular Disk, its Figure, as t muft be fpherical, though it is real roidical. 8. That the Subftance of the Sua i is thus provd: The Sun fhines, and his f collected by concave Mirrors or convex L burn, confume, and mele the moft Bodies, or elfé convert them into Aft Glafs. 1.0 Wherefore, as the folar Rays are Cee nifh’d by their Divergency in a Duplicae: Ratio of the Diftances reciprocally taken, evident their Force and Effect is the 1 whencolleéted by a burning Lens or M as if we were at fuch Diftance from where they were equally denfe, The - Rays therefore, in the Neighbourhood of the Suu, produce the fame Effects as might be expected from the moft vehement Fire 3 confequently the Suzis of a fiery Subftance. Hence it follows, that its Surface is every theydefcend beyond an hundred Fatho ms, the hotter it ftill growing. Dr. Boerhaave adds, That if they venture farther with a lighted Candle, than the Place where it puts their Candles out, the Place fhall where fluid ; that being the Condition of be found immediately full of Flame - as once Flame. happened in the Coal-Pits in Scotland, where a Indeed it is not abfolutely determined, whe- hardy Digg er, defcending to an unufual Depth, ther the whole Body of the Suz be fluid, as witha Light in his Hand; the Fumes, which fome think, or folid, as others; but as there are there found very copious, caught Fire are no other Marks, whereby to diftinguifh thereby (they being no other than Oil or SulFire from other Bodies, but Light, Heat, a phurgreatl Power of Burning, Confuming, Melting, Cal- and burnt y rarefied and volatiliz’d by Hear) the whole Mountain down: cining, and Vitrifying, we don’t fee what It feems as if Nature had lodg’d another fhould hinder, but that the Swz may be a Sun in the Center, to contribute on its Part to Globe ofFire like ours, invefted with Flame. 9g. Since the Macule are form’d out of the Solar Exhalations, it appears, that the Suz is not pure Fire ; but that there are heteroge- neous Particles mixed along withit. As for the Diftance of the Sun, Aftronomers are not agreed ; the Reafon is, that the Determination thereof depends on that of the Parallax, and the Parallax of the Suu not being to be found without a long and operofe Calculation. Some make the mean Diftance of the Sun from the Earth, 7490 Diameters ofthe Earth, others 10000, others 12000. The learned Herman Boerbaave, treating concerning Fire, fays we have two vulgarly reputed Sources or Funds of it, viz. in the Suit, and the Centre of the Earth. For the firft we have the concurrent Opi- nions of the Philofophers ofall Ages, except one, who held the Sum to be cold. As to the Central though our Obférvations do not go fofar, yet this is manifeft, is an ample Proportion of Fire d ; and even that Fire appears uch more abundant there than on the SurC fo that at leaft a fubterraneous Fire i ult be granted, Thus they who dig Mines, Wells, €c. conKantly obférve, that while they are yet but little below the Surface, they find it a little 3 as they proceed lower it grows much » as being then beyond the Reachof the 73 Heat, infomuch that Waterwill freeze ly ; and hence the Ufe of : a little lower, about the giving of Motion to Bodies, and to the promoting of Generation, N utriti on, Vege tation, Germination, €c. of Animals, Vegetables, and Foffils; and that all Produétion s, under-ground inparticular, as of Metals, Salts, &ec. are wholly owing thereto. Howthis fubterraneous Sun arofe mayadmit of fome Doubt ; whether it were form’ d there from the Beginning, like the Sym in the Firmament, or gradually produc’d by a fecondary Colleétion of vague Fire into this Place. What pleads in Favour of the former Opi- nion, are Volcanoes, or burning Mount ains, which appear to have exifted from the frft Ages: For Zitna’s Flamesare {poke of among the ancient Poets, as even then o great An- tiquity ; and fuch Mountains are found in the coldeft Regions, viz. 2 bla and Ice= land ; as wellas the hottett, as Bor neo, E8c. As to this, Mr. Boyle obferves, that it cannot be reafonably pretended, that the fubterraneal Heat proceeds from the Rays of the Sun, fince they heat not the Earth above fix or feven Feet deep, even in the Sonthern Countries. And if the lower Part of the Earth were of its own Nature cold, and re- ceiv'd the Heat it affords only from the |S, By the deeper Men defcend therein, the lefs Degree of Heat and Steams they would meet with, Dr. Boerbaave adds, that as to the other Opinion, it is urg’d, that fuch Source of Fire might have arofe there in Time, on the Principle of G ty : For though Fire be by Nature equally difr fifty Feet, it begins to growa little feminated every where, yet as we fhewit to armer, fo that no Ice can bear it ; and then be a Body, and inveft with the other Proed the deeper they go, {till the greater Heat, pertic of Body, it muft have Weigh s t, and ull at length it endangers the Stoppage of in confequence thereof muft have a ‘I endency Refpiration, and puts out their Candles. towards the Center. 45, a French Author, who had the | Hence it muft be accumulated deep under to defcend himfelf into the Mines Ground ; and the more fo, the nearer the Hungary, fome of which are three or four Center, which ma be efteem’d the common hundred Fathoms deep, relates, That after he had defcended about an hundred Fathoms, he Came into a very warm Region of the Earth, Which lafted to the Bottom of the Mifie ; be ing fo hot both in Winter and Sum , that the Labourers ufually work without their Cloaths : t€ adds, That he himfelf was {carce able to bear the Heat. He was further told by the Overfeers, that ic was univerfal; the lower Seat or Receptacle it all tends to. This may receive fome Confirmation from hence, That the central Space is a d to be poffeffed by the heavieft and moft folid Bodies ; but we know of nothing to enter the Pores of thefe Bodies, and make them more folid than others, except Fire. Upon the whole in the firft View, there fhould be two great Fires, an upperor folar, and |