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Show 30 SOLAR VOLCANOS. NoTE X V. r · t 'vhence it may not be neccffary that a planet if thus projected from !TOrn 1ts equa or. v f: h {i • the fun by explofion fhoulu again fall into the fun. 3· They ~vou!J part. rom t e lll.1 s lurfa~e ·with the velocity with which that furface was movwg, ~nd With the :el~~ lty a quircd by the explofion, and wuu!d therefore move round the fun m the fame dire wlnl in 1~hich the fun rotates on 1· ts ax1· s, an d pen"o rm e 11 ·1 pt1· c or b'I ts • 4 • All the . pl an• ets wou c more the f:.tme w:~y round the fun, from this fir(l: motion acquired a: leav1ng Its furface, but their orbits would be inclined to each other according to the dtfl:a~ce of the. part, 11 here they were thrown out, from the fun's equator. H ence thofe wh1ch were e~etl:cd ncar the fun's equator would ha1·e orbits but little incl.ined to each other, as the pnmary plJm.:s; tl e plain of all 11 hofc orbits arc inclined but !even degrees and a half from ea~h other. Others which were ejetled ncar the fun's poles would have much more ~cce ntn c 01 bits, as they would partake fo much lefs of the fun's rotatory motion at the tune they parttd from his fur face , and would therefore be carried further from the fun by the ' 'e locity they had gained by the cxpl o!ion which ejected them, and become comets. 5 . They would all obey the fame l:nn of motion in their revolutions round the: fun ; ti is has been determined by alhonomers, who have demonfl:rated that they move through equ::ll areas in equal times. 6. As their annu:1l periods would dep~nd.on the height ~hey rofc by the explofion, thefe would differ in them all. 7· As thetr diUrnal revolutions would depend on one fide of the exploded matter adhering more th an the other at the time it was torn off by the explo/lon, thefe would alfo differ in the different planets, ~nd not bear any proportion to their annual periods. Now as all thefe circumfl:ances coincide with the known laws of the planetary fy!l:em, they ferve to fl:rength en this conj ecture. This coincidence of fuch a variety of c ircumfl:ances induced M. de Buffon to fuppofe that the planets were all fl:ruck off from the fun's furface by the impact of a large c,)met, fuch as approached fo near the fun's difk, and with fuch amazing velocity in the year 168o, and is expctled to return in 2255· But Mr. Buffon did not recolle<'l: that thefe comets themfd\'es are only planets with more eccentric orbits, and that therefore it mufl: be afkcd, what had previoufly fl:ruck offthefe comets from the fun 's body? 2. That if al l thefc planets were ilruck off from the fun at the fame time, they mufl: have been fo near JS to have attraCled each other and have formed one mafs: 3· That we !hall want new caufcs for feparating the fecondary planets from the prim:1ry ones, and mufl: therefore look out for tome other agent, as it does not appear how the impulfe of a comet could have made one planet roll round another at the time they both of them were Jriven ff from the ft1rface of the fun . If it t1wuld be afhd, ,\·hy new planets are not freq uently ejected from the fun ? it may be anfwered, that after many large earthquake~ rrtany vents are left for the elaltic \'.pours to efcape, and hence, by the prefent appearance of the furface of our earth,. earthquakes pwdigiuuOy larger than any reco!·ded in hiltory have exi!l:ed; the fame cir-um{ bnccs may h:.,·e affctled the fun, on whofc furface th ere are appearances of volnnos, a defn ibe.d Jbove. Add to this, that fom e of the comets, and even the georgium liJus, may, for ou_;ht wt: know to the contrary, hal'e bu:n emitted from the fun in more NoTE XV. SOLAR VOLCANOS. JI modern days, and have been diverted from their courfe, and thus prevented from returning into the fun, by their approach to fome of the older plane ts, which is fomewh:1 t countenanced by the opinion feveral philofophers have maintained, that the quantity of matter of the fun has decreafed. Dr. Halley obferved, that by comparing the proportion which the periodical time of the moon bore to that of the fun in formt:r times, with the proportion between them at prefen t, that the moon is found to be fomewhat accelerated in refpetl to the fun. Pembertou's View of Sir Ifaac Newton, p. 247· And fo large is the body of this mighty luminary, that all the planets thus thrown out of it would make fcarce any perceptible diminution of it, as mentioned above. The cavity mentioned above, as meafured by Dr. Wilfon of 4000 miles in depth, not penetrating an hundredth part of the fun's femi-diameter; and yet, as its width was many times greater than its depth, was large enough to contain a greater body than our terrelirial world. I do not mean to conceal, that from the !a ws of gravity unfolded by Sir Ifaac Newton, fuppofing the fun to be a fphere and to have no progreffive motion, :1nd not liable itfelf to be difl:urbed by the fuppofed projection of the planets from it, that fuch pl anets mul1: return into the fun. The late Rev. William Ludlam, of L eicell:er, whofe genius never met with reward equal to its merits, in a letter to me, dated J anuary, r787, aftf'r h:lVing ihewn, as mentioned above, that planets fo projected from the fun would retl!Tn to it, adds, "That a body as large as the moon fo projetled, would d if1urb the motion of the "earth in its orbit, is certain; but the calculation of fuch d.iHurbing forces is difficult. " The body in fome circumfl:ances might become a fatellite1 and both move round th eir " common centre of gravity, and that centre be carried in an annual orbit round the "fun." There are other circumfl:anccs which might have concurred at the time of fuch fuppofed explofions, which would render this idea not impoffible. r. The pbnets might be thrown out of the fun at the time the fun itfelf was rifing from chaos, and be attracted by other funs in their vicinity riling at the fame time out of ch:10s, which would prevent them from returning into the fun. 2. The new planet in its courfc or afccnt from the fun, might explode and ejeCl: a fat ell ite, or perhaps more than one, and thus by its courfe being affected might not return into the fun . 3· If more planets ·were ejetled at the fame time from the fun, they might attract and cli fturb each others co11rfe at the time they left the body of the fun, or very foon afterwards, when they \\ ould be lo much. nearer each other. |