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Show 200 EXPLA N A TIONI!J. axis being introduced through the box, w1th a small disk upon it, so arranged that its centre is coincident witt the centre of the globe of oil, we turn the axis at a slow rate, and thus set the oil sphere into rotation. "We then presently see the sphere flatten at its poles and swell out at its equatot, and we thus realize, on a small scale, an effect which is admitted to have taken phice in tl1e planets." The spherifying forces are of different natures, that of molecular attraction in the case of the oil, and of universal attraction in that of the planet, but the results are "analogous, if not identical." Quickening the rotation makes the figure more oblately spheroidal. When it comes to be so C]Uick as two or three turns in a second, H the liquid sphere first takes rapidly its maximum of fl.1tteniog, then becomes hollow above and below, around the axis of rotation, stretching out continually in a horizontal direction, al)d finally, abandoning the disk, is tran~formed into a perfectly regular ring." At first this remains connected with the disk by a thin pellicle of oil; but on the disk being stopped this breaks and disappears, and the ring becomes completely disengaged. The only observable difference between the latter and the ring of Saturn is, that it is rounded, instead of being flattened; but this is accounted for in a satisfactory way. A little after the stoppa~e of the rotatory motion of the disk, the ring of oil, losing its own motion, gathers once more into a sphere. If, however, a smaller disk be.used, and its rotation continued after the separation of the ring, rotatory motion and centrifugal force will be generated in the alcoholic fluid, and the oil ring, thus prevented from returning into the globular form, divides itself into'' several isolated masses, each of which i1nnudiately takes the globular form.'' These are "almost always seen to assume, at the instant of their formation, a mo1Jement of rotation upon themselves-a movement which constantly takes place in the sante direction as that of the ring. Moreover, as the ring, at the instant of its rupture, had still a remainder of VP locity, the spheres to which it has given birth tend to fly off at a tangent; but as, on the other side, the disk, turn g in the alcoholic liquor, has impressed on this a movement of rotation, the spheres are especially carried along by this last movement, and revolve for some time round the disk Those which re· volve at the same time upon themselves, consequently, lf!.BULAR HYPOTHESIS. 209 then present the curious spectacle f l at the sa7ne t-ime on th.e7nselves and~ p han:et3 r~volvin.g nally, another very curious effi t . 'ln It ezr Ql ~tt". Fl .. these circumstances. besides thei~e Is :. so manifested in i n t o w Iu .c h t h e n.n g r. evolves, itselfe othr tO. Ur l.a rrre I b sp Jeres V\'ays produced one or two ver s~alleie ale al~ost althus be compared to satellites y Tl ones? Which rnay we have thus describe-1 pi·esen.ts 1e expenmellt which · · ... u as we se · · miniature of the formation of the 1 e, an Im~ge In t~e hypothesis of Laplace b tl . P anets, according to nngs attributable to the c~nd~n 1e /uptufre of the cosmical sphere."* sa Ion ° the solar atmo- Such illustrations certainl t d t lar cosmoo-ony the chara ty enf o take from the nebu- h. o c er o a " s 1 d · d . . w Ich o~e of my critics has a )lied l? en 1 VISIOn," al~o remind the reader that th~!e . to It. I may here this hyp?thesis, besides observarf~ e other grounds for Overlookmg the zodiacal lio-ht . ns on the nebulce. a residuurn ot the nebulous ofluidwh/ch ~as been thought geology taking us back towards as~ t ourf system, we find. c.ann~t otherwise be explained I~ e o our globe which time In a stateof io-neous fluid. t. tl was cl~arly at one oblately spheroid~l form \Vasl y- le state In which its c.entrifugal force. Since th a~r-~med under the law of the exterior crust We th enh I ~s cooled, at least in · · us ave 1t · chemical process attended by d. . . h .passmg through a the heat at firs~, if n·~t fi:om tl ImmJs . lll9 h~at. '\Vhence nebular hypothesis? But thi~e i~auses IndiCated in the ~ack along the steps of such a not all. In looking Imposed. There is nothino- t process, we have no limit V\•e re~ch one of those extre~eot call for our stopping till vaponze the solid materials. ae~pt~.atur~s which vrould that condition of thino-s wh. h . . I~ g1vcs us exactly comnogony. 0 lc Is Implied by the nebular Of particular objections it is n t T.h a. t theIr e should be difficult'u ~s ao tt enne d~lneOs's sauryc hto sahy much• sis Is on y to be expected. but ·h o a . ypothe-ro strong, we should cert~inl bV\ ere general evidence is mg them too much weight.y ;t sf;upulous about allowtlance, that the Inatter of th 1 I epresented, for inmy conceivable gaseous forme fisl~ ~~· system could not, in ' e space comprehe d "'Dr. Plateau on the Pheno n - .. ~ass ~ithdrawn from the acti~~I~~ pre.~~nted by a free Liquid ., Diemoirs. Novernl.Jer , 18"·1" 4 . gravlty.-Taylor's Scien t·1f i P. 1.. v . 17 |