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Show B fm Wfttoaripler days aT ccrrai i I QBlviTATlOS ANP.6i3jiTIllF 9, I c Q AIi WOES. IS' I t"c,al0.?,,l 01,,VM,,?T';0' 8E,S?' U Mind:mLAi TiAonaeU, at 0. Sf L, VJjf, H tliAYnTiolafoTee r exerted octwctnjai , . ntUla';of matter aa'haWnlTerse. Twc 1 H .re iwrllcle or'avasiea", of maltor, plaied i S wUctf hava amutuaV tendency to prcta'tb J i,towardi"cacbcthe.rVf;ce&tr" '' . v. B triinro i equal' ind In oppoelte tllrccti MWer,'gteai!inay-b "thoi.dlfferenco 1 H, vntltlest)f Hijtter; for instance, btuv po .11 Utxrtatbb 'game'prewur(.poh tbe nl H: tlio trlb, as tbacartb excrta'upon frata H lid height; and as tba.twb-forcea.l 5,- S' fiwctldaa oppoailo to eacU other, the Or. 1 X 'wfiSBntfreraainat'.rMtii "I. 9 Utiakdbfjnattetcxerted a greater. "ttwotherlnVtheir sautual pteasurei, i f H abgdie cinipourided of, tlieso dlffe B r' VonH necessarily mova with a av H ?tt,Iellertd inolloa "in the dlrectit nta B rWaterprewuro. -Tbl may bo reprcae " B rtamumU of "equr weight in 4 Pl'off'iri oppoUtt dlre'ctlonst If ;prf a . t,a on-the-two- boats-la w rLrUlrcmaln at rcstr lf the forcovof Q M S?'1' -war the other, there I1I B S!fJ'feli"'.but a rboHoa in "the "d l?S B fce'ffyrcaitexertad, B w1? wl wwea oi matter, not Oir S .MJfotceof.pre&suraheninvontacl DfX B iSl,tt4 they manifest tv, mutual fEZ, B tMh other. Py'virtUool ! IB SaM101 -'raincd, they -will i & 9 Sjhother vlth a uniformly Sr,??lbn- If mas of matfar, eiei B ffil A1 JH towards that aorlace i H- tSfaT.y Pfoportlohal.to. .thelrms S rfMtberriWofuebody la I 9 iawl!fr?s.UmM Ercater, Ita vcl 4. 9 yroaals one hui -X 9 SLPr' lV,oclty W'U bo tha:onc 9 torn? 5bat,fif tbt ,n,w jO. SI aotloalnamoTlnjf body la i tttlea, ot motlba" are " alwaya "exactly equ Therefore, when they mcet.they trill mutual ' destroy; ,aach other motions, and rcai rrst. i . -Thusr U trllf be; pcrceed, that the force ; gravity la cxhlbUad jtt two way; namely, . ' preisuro and by motion. Both of these fecteareijsed to measure the force. Wh gravity is measured, by Jrfesimrc. the resuli ; called weight, and to represented by 'the nu; bet of ouncea.iptfimd, ton, &c W"eB ". tneasared by motion, therresuH la detcrmin , to the apace through htch a body oje ,. gravltatfoala aglvcttttwe; Hfcwton tfm( , atreltd by cateful cxiiertmenta, that ev 1, kind of malterf near the autfaco of the. ar falls from a elate of rest, through ,qtial,spa la "equal tiaica, whea Ihe. Wslatanctf ot .1 fttmonphcre, aaft'Jother; disturbances are IiuoVeJ;, v' , . s A , -'the srftce'throiifih .which oub bodyfalls fr a State of rcit'towardi'Hnothef la' one sect of Jime, ia the astronomicat measuro gra ' latlOnV'f he" !plwe3s"muny estimated lni.net br,fet,. ''fho space Jriroogfrwhkb ajjody fa from rest In this latitude, Is 1GM2 feet 193 Inches, Ih otae'Wcoh'd ; , - ' " In' idoptlpg' thti .'rafcisure. of the force graT(ty, 4hore are three Trnlca;which; should , ell understood and carefallyibsctved,- q. r) Sttvc ilisiK,?Tht 5( through tfXtA 'eas & it Jiy tirtut of iJ JfritkAvUvk" Uticajd$ -pnotitr '"i tti,donnotUpiaijitpiiri thejnax vf tht'J j , ntr, hit U (U iatnt1 irWever.mtj.lt Uf tnaiijy if, d&wcetartiUtmi, !" TbusYtlie Sunt gtaTltaUa'towardSvilupit and the'tarth griritatee toWadsoJtipUral Tjijt though tbe mass of the ;shn ltft?J80J 7 tiines greater thdn thd masaof fhe. earlli, ; the gravitation of thefotmo-'.iowarda u upl ls;"exactly;tcsoftl ,io. thoi'gratltation ot,j 'if latter toward; TiteJ wIteu'h'Sijnj.atd ca K' 'mis equal! distant jfdmchlmj fn,otherwor - the Sun and catth; hcn. Htt equal; dfsfari from' Jupiter, mote Ihrou'gh the samo-'jibm of inehea'rpars of Inches toward:Joplter . oijo jsccond of tims; , . JVnd"isoebrmuat always" I ' tbe ce.whatcver",raay,be'J therdiuerucea tho'massesf any.vhumue? of'3uolng-b(K , V towardsanothef bodjV " fri 'i-'Ssctwo Hu'tB.rr JA ipaet ihreugK uhkhMdte Xi iKtirsramlitiiMi mox tvaardi'anathcr?h pni' la it proportional U tte tiiine ftfii taUtr,if the ditto litem thifwmr. 'and mtrjtnutiiitKttamt. f Thutif the tnats-', toward1 which .'a. b gravitates : la iloublcd, Quadrupled, e'.y number bHnchea which'tbei gravitating b will pass' ovcrln,oue second, will., bo doub "quadruplfKC&O. Suppose that tho- Smt , Jupiter. "are ;at equal dlstancea from Set) a theSunJcoutaln"il04& times' more ran , than Jupiter,, then wh'aterr way be tho'Qi jcr-of inchea ''tlifbugU, which Saturn may j vltale towards Jupiter iti One second of timi will gravitate towards itlio Sun in the & tlmt 1018 tfmca that nnihber of Jnebes. airily the former in mtttpwl otimtll .w rcrt dy proportional to-"thi'iiaaritf thtif K - frmmn. V.t. : ? " - ,nu9lS,lfrJ.the. -.disladce, o::tbe- aurfae J the -earth from llta centre ?e '-called. .1, the'BrVafie passedpvcc.. byn7a tfalling ""! ' ncarsthe surfare is Blxteen.'fectJaas J ' of i tlme;7i?nhcn--atv.-twicO tbe .dlsfc : " frouiithe centre of the? carthj- abbdyiw full ono-fourth of'slxteenfeet In oae. sec At ilu'ee times 'the dlsinnce; a body would ononinth ol sixteen, ftsctr .'At four' tlmei iliitahv one-slxtcenth of. sixteen.. feet, Or foot. -At l3?ty , times. thedtstahco,.' rom centre of 'the' carth.tdlU surface, uor at distance bf the moon, a body woUldfallln srcOhd, tbe'pne-thlrty-slx " hundicdth pat sixteen, or about ono-lwentietb pat nri loch. The Bun, being 400 Umea, more taut than tbe moon, folia towards the. earl . orieaecond, tbe J4CO,O0Qthpart oj the 1-m, 1-m, 0f ftjj Inch.equal to the l-?,20P,000th pait i ah; lucW While Neptune, being 80 times i rcw distant than the Sun. falls towards the V ' in ope second tbe J-OOOth part of tbe J.3.! ! 000th of anlnch, which laequal tothe l2,f OOO.OOOth rt cf aa Inch- remaps snts nauicucs my iuhuiid uui law of gravity is known to bo true? D It known that the force called grovli dec cases aa the square of the dh rt lncrea8csT "vVhQ has ascendod the hi J of heaven to expeilment upon-force? upon-force? Who haa observed any phenomc whkjt he could exactly determine the frai of an loch through, which bodies wpul towards thoiarth in one second of tlme.i f vast distances of theTaoon,Hun and pi The answer is, that all mauklnd, of ever, , m havo bsheld the phbnbmcn?i which ii ' the" data accessary for the solution c grand problem". AH have beheld the rcrr circling itslf around the earth,- at the di i or of about 210,000 milfs, or at. the di f Jn of CO acml-diamnters of the earth fr in- centre. All might have known .that t This must mote Irl a straight line, when on ons, in motion, ttnless deflected from thata tbe line by sOnw force.- All might have ! rand that the orblt or path f the moon was .. " .X..' Iutnfr ifolbrttMl1 BVe i the mcntfroma'ttrsight Hue, called lia ta rm Into a curved line. AU might have ) two by ashnplecah-ulalion, the exact axnc this deviation from tha tangent to tbi force in one second of time. Tet, strange as then appear, this slmplo phenomenon, thou rent- served for thousands of years, was note unt- hentled till the Jmmottal Newton, son m of centurlea ajo, solved the, simple, p nted We say. simjdo problem, because it la i coii- easily solved? but 1a the day of Key ' the was considered the greatest dtscoyci iu'al,. ever was unfolded to thtf mind of man ono Thus we see that, the same force i not makeaatitonc fall 103 Inches In one Irc'c. causes the moon tu fall SfiGO times less, tlwtiamotlme, If gravltatioa did not only Ha Intensity with tho distance, then lb t,but would fall with the same velocity aa ast g"ra! ;tho earth surface: If the velocities d. f.thf merel r astheaUtauee.thon the moon, I movii semWlameter of the. earth distant, wc ibeel. GO tlntes slower: but its Wliog, vcl rated known tcbo 50 tfmes 60, or OO tlmei ty to being, m before statodt only about thi while Qfanlnchlha-sccondj , t, 4li meet The mean ecinlHllamcter of the odtes nbout "S95u.2rnllcsi tho mean l$tan uses' sunli"nbout03,3CW,OW)mlles. TheI? odlbs tance divided by the former gives a qu other 21089;that Is, tbe sun's distance is twics 31083 srmtllamcttrS otthe euith; tJTi half or multlplied.Into Itselfis cqua? t? 00, Ibclty If the auo contained only the same at o'dred waiter aa the. earth, then the latter j hun. deflected from the tangent ot ti orbi The enrre towardi'tha- snn with a eloe qusl S7P,9Jl llmsa less pr aacoad, than t sU ated time greater: Its deviation from the lly gent of its orbit Velag aboat the. T4Mi ! da inch per secoad; or, mora accurately, the fall toward the sun about 1,409 time etc of than a stone tall neat the surface of the ai by Now, K 660,270,921 be divided by 1,499 cf quotient will be about ES0.551 ' that is, the en contains B89.G51 tlmuS more, matter tbaa 6 is earth; and thus the earth fall towards the m 380,651, lluus faster than It wpiild, if the i ', Is of the Ma, , vera, ,inly; equal to. that of, ied earfbi ,.t. j by Neptune being abeul SO times th dlst oai of the earth from the sun, fatla towards ery latter, with a velocity about 000 time th,. than the sailing velocity of tha earth- ton e that luminary. . the A planet, twice the distance "of the xe from the sun, will fall, four times less dl.it I tU wnO KCCUuMi, UinNNn. xud uivtuuv m JfatllngVeloeltywlU be nine time less at nd tlM th distance, Sixteen, tlnles less; a yl-- tltttps" th dtatancei ,oae .hundred time iea &c,-i &c ,. dh? swTMrtbifc.FbKCtB,--A we, have 1 o the law of grttUatlon, an.detqrmlqed, a piir measure of Its force for any j?lvcn qia of of matter, and for'any glvea rlktance, bo jet u cxsmloo the. "tiaturo of thoso. opp fofcesi by whlch'the planet' arid satellite odv prevented f ron. falling' one common e , -4 v-i fn'my firatlecture, I pointed ont the.ti for.' pleof the composition of. force and mo Ms thata:lwdy; acted, upon byij.wo forces : move In ;a' direction .Intermediate .be fir, thcntitflf oneorthe twambtlflni w unl isrf; whUetheither,l.5aceItcrated, the Jnt 5S1 "dlatpath.will bo a curve; Its concavity vet InlheJlrxwHon'-of hevconatantTorca, iter pwduws;thefUlle;ratlonoi-. the i-'fMt thelanet and sntellltea' oFour; rili "are'im'dcr.thelnlluericoof a,;proJcctll foi rJe, nTbrteVwhich;oHgIoallyBavo.-tbm m ice and then ceascd:tq;act; 'the' atae';-a p bcr 'ceaseaito act upona.ball, aftor thoirnom rfn "explosIon'..ij;:Withgnt, a resisting medio: ilie iome! other extraneous caso,'thi plai i tt bodlea' must'have contlnued to;. mover, foi lies lathe straight line Ja rwhlch, they wer '? i Jdcled..illut"gravIt8Uoa'every,taoracnt.d .is.. lUMtln. V.IVarnlTVit.'1tnn tntA'-ciirv! SSi brbltsi " Tho nature of these orbits, will t S P6i tho' lhUuslty nnd. direction, Of-tl forces x X;-'--lsiz ".'"' i; tv 1st; If -tho- notion , arising , Jrpn proicctlott- Is at. right anglej to :thoM 1," irltlog from gravitation, and If lbe .velo the former la exactly 'proportloncd 'to I JSI the' Jitter, so a to keep' the body, ot all i. at the same dtsJance.from the"centre:lti SSI. WHl.be a circle;, ' . , , 2nd.' Though the projectile Velocity "l!' actjyr such as.woull produce; a circular. ,i when operating at right, angles to.:tb " tral force, yet. If operatlng.at an acuta iam? fuse ang0 tbe latter force, the bod Velocltyiwlil.be equal to that of Its projt "f Srdi If body be proiccted at ilghtar theccntrul furco witb'.a Velocity insufih produce a circular orbit, ttr,wlll 'desci ,'f ellipse of "which the. point of projccllon theaphellontV f 'v thai -1 tt Pfbjeetcrl at right ot the central force with a. velocity somewl great fbr.'tlfe central-force .toTdeflecr.lt m,.M circle itwill'toyblvelu an.elllpseof wj: 1?? , point of projection wiir.bci the petlhelfo; 6ta- If a'by.be prbJwfedin aHne.i tho an al-nte or obtuse angle with the dlrei - one tha central force, aud, wlth":a velocity what smaller or greater: than that vrblc the tbe samo distance, and acting at Tight i ii'ono t0 produce a circle,, it will desci ,l: t .ellipse. p i Oth. if the projectile velocity is i dhi that vrhl,cli the. body wouldjacquire In. tli in ffom.the point of projectlon to tho sun, "0th describe a curve called a parabola; the t oran thlrf case, wohld follow one of the bran mora n'1 curve with a retarded Velocity far the limits of our solar system", never to ?; to It again. ogo' 7th. If the projecllle velocity la i than that which a. body would acquire this lowing from the polntof projection ta t n u It would describe a curve called a byr fttlnn Aa tho branch of this curve in which tb ?;i is moving, extends, like the parabola infinite distsnie, tha.body never could thi. again to the solar system nx h Tho circle, ellipse, parabola, anil byr tton are the only possible orbit vr , curves Ii ', j"., bodies can move under the. influence ,t I h. jectlle and gravitating forces. At,a given distance, there Is only" oni nr city of projection-, which will produce i ,3 lar orbit! and there, is only ono velocity tfhn will describe a parabola: but there 1st Jz.Z nl'e number of velOcUie which wiy pro .Uince Infmltenuiaber of elliptic orbltavbet straight line and a tlrcle. And there u. an innnite number of Velocities wbl rJiZ caufic bodies to describe an. Infinite nun JZ?A hyperbolic currcs-flf different forms. ItShf All the planets and satellites of ouf rrilin describe ellipses which do not vary muc tnown gjjgj, BoBjcoftho comets describe ;""'ca very cartofif c: and ome of thet'n are i LZ?t to describe parabolas and hyperbolas. S tile forces, that they may bo properly U,Vrv tb any given central torces. u It For the sakeof simplifying ojtr slit m V let us suppose bpdles to move Jn drcl? i Smrfre- "ral force. It is required to d, ?Ln what effect different velocities and t ?A Utastrlug one foot long be attacb it toll of lead of the weight of one noun be whirled around la a.horliontal plsn will have a tendency to recede from ' , ,i tro: the greater the vclotlty Of revolu greater wilt be the force pulling .terfn. string In a direction ontward from tb ..during W(J&cauB4the,centnfusal force. w? lp Aringiirformsar.evolutlSnlnl.0935: Tr ft vrifl become stretched, by tbe ctr, ooe ncar j Tt fqniUo the force of its weigh xjMtA. Xt forcawlll bo eaual W on -M Mi tet'tho velocity of reTglutlou, which cSy K one pound of ntrifogal force, be re Jttth 'yStt?poe the string connecting tbe 1 1 1'?tb theentre,-,tolw varied tn its length -..ij. I. Velocity lematns the same, what i, 3 Vh law of force exerted upon the slrtnj 'tt rdls experiment and wl?ulatton deroonst bUentoi mthfciam vihcitptfo vntrifvgd, squared Examples; A string ope foot Ion 279 921. certain velocity, generate a. ccntrlf uwitof ofone pound.:. AWng, ?ould W force oi half of a t in to a third of a pound; ten feet long, ohe- taa ihrndk a xe oaly half aa great, la tl t aa ttawi a that through which the Bearer I Kth dex4ec4d. At Hiree times the UlaUnce, t pwer aiosl.tlae.-tbfrdr.thatof 'tha n itttt, bbiW. AttcntlBScathedJstancathodtfl the k ty oac-tehlk of that of the' nearest sua .,c. Tha force xed pba the" the bclar a the deQectlohs; and the dcflteilc sua lac iaverscly a the distances therefor bm t?eatrifaalforces Baust be iAVeraaly as tb the taace. . '- J -- ' : . 1. ", Next, Uppoe that the.velocKj'of tha r ance tag ball to. bd varfed, whllo;tba lepgth. tKb tiring, coaaectlng It. with tho centre, re les thes4te. What will to tbe law of te apei tho striBgf la thi:eaei the foreier, both experiment and mathes arth calculation prove that, aace Wktu&ilmathniftht itrinj femaini tht s, Its tfcitntrifvsalforittariH dirritytttAtiwa , four' crtocitv. . ' .,' ttea Kxaaples:. istrlnsono foot long, v lew; velocity equal to one. generate a centi , force equal to one pound; if' the,' same' b w&ed the' end of the string, Jatoaue to rovoW vtcy twice theVelodty,, ilicforce exerted upc nutj stribg. wlU.be four pounds: if the vfcloc hcxti hree, time a .great.?, the"', string w oglne atrctebe'd nlnes;p0undi If theovblviog,vi s are 1 Ore times as great, tho, tension on the litre 5 "'U to twcntynveipoundk:.ftthe c)rcul rlncli Jocltyof the!"bU.ri.r600Ctlin"ea, a."gre Uonsi a exerted upon the String -will. he.,S wd'uui P'ftund.'-" -.v -;?; ti-i; tweeri The'reasbnorthU.laW;will.beiperccli form rcflwtlng;.thata,body', revolving ,1a1.' enno' W " e'bel ty equal tobnc, wilt Ue.VdeJ belne itth glVeatlme',frout,the taugei;bf It -hick td thohrvc,; thronghta jspaee; which cii ' -r reprcscnteby ohe: iAVith;twlcelhbw ritem. vjlocjtyi'theidcflectlonj.iri thesame.'tlh ce" or ha four times a far: "with three times , otlon; volvlbg velbclty.the deflection fremiti Birder genMnthcsarae timetwIU bo, ntnOit! sS Mtjto., '&cU..The deflection being-m being-m oif tquareof- the velocity' the;eforo the letary forces, which prouueo these dflectIon ever to the square of the; vclocl.uesi a nro- circle the central. andjcehtrlfugnl for; cflecta lanceeach other and' "are, .equal f.tlieref i,w cntrtfuKal force must bo, as the sqwu telwS vArttoctnlfal force, ivlth.two.tlmei - '-i.h lIty;.mu6;befour.'Um'eB.8Jt;grent,; i". "the under Its Jnflurnce, must fall from. It notion foer tlmcjt'a fit In,', thbme . time.! lty "of "the first halfof the tlmb. Jt. -allfc rtaXh. ihat Vf one part of the spacbcqual to one,qi -times the'.wbole'f during'tho. last halfof the k orbit will fallthrough.three,"tlmea;.a.,-nluc Tiie'rcfoie, tinting the, whole time the fi'eX' oJspab.fallehlhr6ugli from the taDg "orbit, he -.equal to" the;uta bfjthe pac loicen-"1 throughdurlng ihe two equal intervals or; oh' that Is, equal to four , yinust fifths central force,' 1 Jjlne tlmc iWa, tti;clrcular ,vlUy sow: haitlwea, sctlenP grwt, and the. fall.pt deflection from: lglcs fo gent must be alno" times Mfari for dt ilent to tlrst third of the "time, tbe.eacctlbn ribo hn one part of.thb space'equal to ona.niu will be "wholes the next.tliird of tho'.tlme, l -win bcdeflccUd through three parts ti igha to the last thlrd.of thetlmcit; yrillfbb " liat totf through five parta,,tnore: one,;three, i Into . a being added ti)gether;: will be equal itch the These "are the -phllosbphicalireasons-n"-: " " deflections and forces vary directly ait! baking of the velocities;, i'.;,- "T'V .. " , stloa.of By a combination of thesettwoJaw some- tain alaw still moio general, appllcat h (If at riven length or' th'o'.stringv' and' ta ai mgles); velocity of the.whitllng ball, ,tTh: v I ribo an be expressed pi follows: , . . iTte'fmtionitfttrwgtpdfrtcttyatJ inai to thtttlxitiaVrwiavilshteaac, falllnV and nrrr'y or fAr Itng&t'. It'-wlll BxampUsr A airing, one foot longs jody, In velocity. of one, will exert a orce of cbes of equal to one pound. . beyond A string; four feet long, with a or return weight attached, and whirling with a of alxV.wllt exert a centrifugal forca gteater nine pqnnda. In foi- A weight of one pound, attached to be sun, ten' feet lbhg,.and whirled with a lerbola, equal . to twenty, will generate a e body force equal to forty pounds, i to an A string, 400 feet long, "attached to return welght. and having a revolving veloe to thirty will stretch the tririg cqus lerbola, and a quattcr rounds. i which To determine the Utmost tension th ttf pro- Imparted to.a string of giveu strength Wtmihe tfftflglh f ttri3i iMtnadelova veto ly,at the tguarti of their (tngtkti thtn th j icircu voMtqwirtUtuhjthtityvtll admit cft - which attht Inviru tmtari root cf their laigtht. m infl- Examples: 1 A wcfght, attached t luce on of a certain given strength, onqfoot ireen a revolving with a velocity representea ii also will support, at it greatest possible :h will before,brenling, a centrifugal force rc uber ot by one. 2. A ettlng four times aslong will, system to the nsiumed .hypblbesis, be slxt h from weaker (one sixteenth being tbe Inve ellipses of its length)! and the greatest revo ipposcd Joclty which jt cap endure will be b being the Inverse gquare root of it r projec.l'thQ.stitng, reprwcnting tne central adjusted l ing sixteen times weaker, tho force, ijeceesary to balance It, mijs emcnts, sixteen llroea, weaken but the. lengtl raround velocity ' halt will exactly -gencratt itcrwlne fugal forcis equal to 110. listaoccs 3, 'If the string-be '400 tiny loi tho first example.- the assumed. ied to aWtould make itlCO.G 0 times weakc id; Jet It 000th beings tbe Inverse squared of it e. and H and the gteatcsi circular velocity, w the cen- capable of enduring; w f f I ba equal tion, the (l29th being the lnvcfo sfjuafe r ipon the length). In this cai. the greates centre tension which the trjng. will etidi V'ben thatl-160,000llipartof thattn the first Jseconds,, bit the length 400 and. A;cToclty 1 :ula.r ve- exactly generate this force0f tension t, thatls, Tbeee simple mechanical laws are pound, to the retolvlng wbeelaof machloei generates Dtrengthfthesnokea.c-roftbeotberr nrcsented nheehu and their dlameiera, be ki exact revolving velocities, hlch th jail with ahleofcpdurlflg, tan, by theselaw while Its lalttl. - . 1 he the Hat, tho most InteresHpgexhtbltl, rt Both laws; wllllo seen to their appllcatl te that, celestial. machinery of the universe. rM. if & one-pound ball be attached: t rorrtwrtw JWi,,,, centre of the ea - with a equatorial surface. Its length wonl fAit fores miles, which would be.equal to20.t: f rives" If thli weight be whirled rounct the g,gives tan to complete one re l t5tog force eqnal to one pound in by ' log exactly equal to it "1M " saffio twit velocity continued the mat. tody t X have altcady stalsd, that a ha) he do- poqad freight, attached to a KtlKg cartat long, would generate a centrifugal far cctioa to its Weight, if It Is made to rvo body touml la 1.09362 second. . . - tring Now, if the square root of the seaat- ns be of tbe earth, or the square root of 2 o, tl.e fcot (which l eqaal to 4,674,530), 1 ie di)- piled .Into 1.0652 eecoaik, the, pn , leeaualtblBtkxttdetwhlchHev evolv minutes and 22 seconds): this, thereto of the precise tiat In which a body woU ala KroimJ the satth close to 11 surface. , ; Tttowy tbe Moon ia about M ssI- a la of the Vatth Uat, tkstwt sattcal U eqaal to 7,746; this multiplied I rcondawtUhe equal to 86745 aecoeds ' w, 10 hours 46 alnules,45 eeebafta. If gi tafiht -vrerethesaae at alt distance this the periodic time of tbe moon, mil H ilth 1 about 27 days- therefore, hjtt tpkf Ifugal. W about the l'SOth of what it. woali all, at the uppOBUlbn;tha graylfatloa 'ratal with intensity at U tltataaees: but a .the slots' of strligs, when the dhtance slty . It same, are a", the. square of ' the velocl IJl ,!be louare of 1?00 hi equal to- l-BCCWrhei slodty ceutrlfiigal force" at .the dlatahce of, tb string i only the l-BCQOth part of What It 1 r ye. surfaceef the earth: Therefore, sth t. tbo trifugal-and 'centripetal force la .cli 00.000 equal, Btavlfatlon must be S800 timei "the distance of theyluaar orb' than it ffcl-hy wrfaccTbf, the,tarth';; ...i-'A-T"; ".circle "'Letthff earthitnd.TnoOB ,be. Conned letted tiring whose length way bo, represent i orbit, lot the moon tw whltUd around the ei ay:4be ttvclbchy. of n ml'e Iri'lJ seconds; folvlng thecentrifugal fbrce'thuegeheraUdbi ie,.wIU cntell byli;.'-'lt IsAequlredtQ find wh fugal force would bo generated, If .tl ie tan-, were conncclid 'wllh the Sua.by a st ims-a timea longer, and made fa whlrUarbi as the Svith a velocity of 30 miles la .ll central JBythoIawof the distance, the ce s,0must foroeouho tensibnyof the string i but x in .400,time weaker; tlaia when revolvln 9,to- thecarlhi'but. bythflawlbf tlveaqu; ore, the velocity tho.tehafoa oo:tho string-wot sof the timci Rtcaterrrbv dltldlwt the Tatfct ,v .? by tho fotmef tha" qnotent ', will to ! the vc"r 0 centrifugil forc,whfcli the mOou, .a'J.bbdy,- fb revolving aroutvd the .Sutt in comi ' tangent itaprimary,.;l'.2', " times. greater.,1 Purlng generated.' byv 'her' Revolution- rar through -artii.' " :' barter of ThcrefoTeiflhetehslonsofthc.ttrl time, If ecnt the grnvitation, of the moon,' fl h space: eatth and then to the Eon the. forco ramount tatlon to the' latter, though 40O,tI ;cnt will dUwat," 1 ; 2tlmcs-. greater thai ss 'fallen f-orrnerj. hut gravttatloB Increase as I of time, of the dlstqnca decreases: let 4Q0 I "' cr'inultlplled'lritb'itsclf, thofprodui sa -great,, JCO.000: hence, the gravltatloa of tl ,tl-S thaun. "would ha 100,000-times, tho tan thoy were brought 400 timos nearer lirlng the 21tlm'e " lOO.OOO aro equal to 3G0.I i will be feprcjents the' whole force of the 8u ith Of .the parei withthat of thifearth,;whett; t the body piftced at equal distances from .t note; and .Therefore;, If - large scales wcte deflected Btitudlng upon the moon", an A if 300, and : five, wcrcpIucJdlrioPecaler-aad ,tbo;S to nine, oljer theywbuldf ii their pressor why. the the junatorb; balance each other. .T bosquare uerivBre'nscd. asconvenient fat "11 I,-' 'v .' but are not sufficiently, cxact-for asj rs rro oh- purposes. ' . v' , ',s r''---t' jlo to any i't,B Biecliahjcal law which I have ny'Kln. constitute perfect balance ' Jn .wh Ia.w-may cnrately-detcrmlhothe i.pomparatlv . . . of iworlds.-.:;.Thb. astronomer ofUl the mr dtty; lg f-,n,lliar with . tbe, process of htdtothetf voxm -ail the"4 chemist ls.i In' 5 , the" IngredUmta, which enter into having a wU. - tension, I hvealreadr con'lnued my lectt v unusual length" or I. would point; ie pound otncr nterestlng,applIcatlons of thes velocity fulinechanlcanftwa. Tha exact thaj equal to adjustments of tho. various forces Of , . the consummate wisdom and skill ei a string eery department or the ut,lverse, ; vtoc'? to finite mindsthe omnipotent i sntrifugal uranjeur displayed la Iho conttruci magnificent machinery of creallon. the same ,,B wajesty and glory of Him who fi ity equal goTOTnV the mighty fabric, d ta two |