OCR Text |
Show )10 EXPLANATIONS. . If this be the case, let it be ed by the orb~t of Uranus: . ted out that the planets allowed as a d1fficnlty. It 1.s pOln 't from the outennost do not increase regularl_y 1 ~ dens~ Yalso not in a regular to the innermost. Theu size~ ar~nerally speaking, are proO'res"!ion though the larges ' g It . ot perhaps tow~rds the' exterior of the syste~. h~ alsdnbe 'observed : to be expected t h a t sue1 1 gr. adatwnt s slo ooku f'·o r then1, their' but grant the~e was sonle \~~~o:r ~nd a slight difficulty. absence constitutes only ar , . the articular" stages Then we know no law to determdlnde t c~ed " Be it so-h . h · re formed an e a · h at w IC nngs ~ f th kind there douutless is, as t e although son1ethwg o . e ·dinO' to Bode's law, observe distances ~f the pl~netsf ac~f~h the ratio of increase is 2. a geometncal ~en~s 0 wh. h cannot now be answered, From these obJectwn~, w IC let us pass to som~ w hlch can. fl ce of atonls towards a It has b.een said that a cor~ u:l~e nebular hypothesis, central p01nt, as P.resumef r Y but in a state of rest.* would result, not In a ro .a. wn, . " Suppos- According to the Nf!1·t~ Bn.ttsh RevleW- l~~e;·ate round ing the uniformly distnbut1d f~t[;Fs ~ob;gt~e slow advance their ringleade~·, thed ~)a~~ e o:~~rging to the nucleus of the atom.s 111 l'a Ia Ines o~centrie eircles, the outer must b~ a rl ng ?oundhed l~y ·~ f the nebulous matter not most cucle being t e Irnl 0 Now as all thE\ drawn to t~e centre of the ~asc~~~.f~~rating particles, forces wh1ch act upon e . 0 f . ce of the unwhether they proceed from the cuc~~ ::.=~ually increasdisturbed nebulous matter' or .from lt 0 ts in the radial ing nucleus, mu~t have their resu ano cause whatever lines above mentwned-there t~an ~e :he mass It must capable of giving a rotatory mo 10n o . remain at rest." b d bt that a confluence proceed- Now there can e no ou . lt . but this is only ing precisely to a centre has this r~~~ol~te description of an abstract truth, not an. e~ac~. a~d The explanation was any ac.tual confluence of ~ e ,Inl~n before the objection afforded by Professor NIChol, · g · better language \Vas sta1·ted, and it c~:ml~ ~,o~bhee~I ~een 1 :;flect on the solar on the present occasiOn· . .t ears that the act nebula in the act of condensing, 1 app tter fronl all ~onsists in a flow or rush of the nebulous rna • ~orth British Reyie'V, No.6 Atl_a s Newsp_a p, er, Au~. SOl ~B4~· l'fED.ULAR HYPOTHESIS. 211 -sides towards a cen.tral region ; w.hich is virtually eq uivalent, Jn a mechanical p01nt of VIew, to what we witness so ri·equently, both on a small and large scale-the meet- , ing and jntermingling of opposite gentle currents of water. Now what do we find on occasion of such a meeting? Herschel's keen glance lighted at once on this simple phenomenon, and drew from it the secret of one of the most fertile processes of Nature ! In almost no case do st1·earns meet and intermingle, without occasioning, wll.•ere they intermingle, a dimple or whirltJool; and, ittJ. fact, it is barely JJOssible that such a flow of matter from opposite sides could be so nicely balanced in any case that the opposite momenta or floods would neutralize each other, and produce a condition of cent·ral rest. In this circumstance, then-in the whirlpool to be expected Where the nebulous floods meet-is the obscure and sim- . ple germ of rotatory movement. The very act of the condensation of the gaseous matter as it flows towards a central district, almost necessitates.the commencement of a process, which, though slow and vague at first, has, it will be found, the inherent power of reaching a perfect and definite condition ... "* The exception presented by the satellites of Uranus to the otherwise unif0rm orbitual movements of the planetary bodies, is brought forward as a startling difficqlty. t · It is, in reality, only a trifling objection, seeing that so many other movements follow one rule, and that we may any day be able to fix upon a cause for this exception, perfectly in harmony with all the associated facts. There was once a similar difficulty in geology-strata uppermost \vhere they -ought to have been lowermost; but it was in time cleared. Geologists found that there had been a fold- . ing over of the strata, so as to revenle their proper and original positions. May we not rest in hope that a similar exception in astronomy mny find a similar solution ? I have thrown out the hint of a possible bouleversement ol the whole of that planet's system : it has been scotled at; but it is only the supposition of a greater degree of obliquity in the inclination of the axis of the planet to the · plane of its orbit than what we find in several others. The same causes which made the inclination of the axis • Views of the Architecture of the Heavens. .Firit edition, 837 t Edjnbnrgh Review, No. 166, p. 24. " • |