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Show COAL. ~4 . . d I {i ppmr e para 11 el with the Jimefrone onfr wh• ich• [I (t t generally lie incltne ' u d which is termed banettwg' As the e ra a dges of them all come out t~ ay: . robablc that the inflam-h rell the upper e . f; entatiOn, Jt ts p f t ~;nth; wholo m•f• w" ignitod by '" ':'my &•pc th•n of oth.,•in tho :o~m o :able part of fome frrata mightfl~~u~;:::n fuch flrata in the procluchSon oft p~~~ ' dews are known to I e [, than others. ee no e vapour; as al beds being fo much wore . . uld :1ppear, that which accounts for fome co . d n·lon of coals from morafles It wo h,l r T l1ave . t f the pro llCl a N ·ve rt e e1s From this accoun o ed beneath maffes of lime- tLOt~e. "' e will foon 1 beds are not to be expeCt M' I 11 of Thornhill, who I hop coa- . db my friend Mr. tc 1e ' d f halk are the upper- ~"0 :·,'~!yp::~~::ith ~i• gcologic•l in.cftig~io"';h~;::~:l~:,; ~m:-fionc, e>lld kot- ;:~ of all the 1ime~frones; a~d tha~ they r~ha~n which covers the whole country fro~ ton-flone; l . I I fuppofe IS fitmlar to . d I at thirdly, coal-delpbs w liC 1 - Sleaford to Lincoln; an t ,, ' L denham to Sleaford, and tram o!l: beds of lime-frone. ea . entl found beneath thefe two upperm . (tone may have been formed by are ftequ yh beds of chalk and of granulated lt:ne- II' f the land, it would fecm, Now as t e f h [, or m va les o r l . . on or beneath the fhores o t e ea, . s of the Larth had been llln \. alluvJatwn, . hich in the great commouon . 11 . others with that fome coal countnes, w l with alluvial lime-Hone, as>\~ as ~ :1: [ eath the water' were thus covcre< r ex ten five plains, whtch no"': co.n _n o ~~~~vial baraltes, cr common gra\·cl~beds. ~r:~ywith waicr, which has fince dl!mnlfhed , alluvi.a l m3ten.a ls ' were in the e:uly t.t mes cro, vd Fort I1 e 1r 0 I.t ( I I) arts of the earth confifltng as the fclitl parts of the earth have mcrea e . {1 lutvc originally been formed or pro- ch1.e Ay o f .a m.m a l and vegetable rccrcmcnts bmleu procefi.e s,. amI as the folid part$ of t·h e duce d f rom the water by animal. and vheg eta as water, 1. t fo ! lows that thrice the qnaTnlll t·y 1 be fuppofed to be thnce as cavy . f earth thus produced. 1IS eart 1 may . d com arcd with the quantity~ ' rounded fand, of water mufl have vandhe • ~ d f alluvial matenals, as gra\ el, I . Count for many immenfe e s o fi e pJ,-,ins as Lincoln-heath, 1avtng may ac · a [uch exten IV •· ranulated lime-flone, and chalk~ covenno. lavina been again elevated from the ocean. gb ecome dry without the fuppo!itwnk of th1e Hdo Ie fo f the ufcs or final caufes of the 0 one o · A h fame time we acquire the nO\\ e b 'ty th"t it converts water wto t t e . 1deed ver flattering to our vam ' ': ·orga!1ized ·world, not II . y b . " crements or cxuvlx • .earth, forming iD.ands and continents y lL re NoTE xxrn. C 6s ) NOTE XXIV.-GRANITE. Climb the rude jlceps, the Granite-Cliffs jurround. CANTO II. 1. 52J. THE Iowen llratum of the earth which human labour has arrived to, is granite; and of this likewife conll!l: the highefl mountains of the world. It is known under \·aricty of names according to fome difference in its appearance or compolltion, bnt is now generally confidered by philofophers as a fpecies of lava; if it contains quartz, feltfpat, and mic:1 in di!linCl: cryflals, it is called granite ; which is found in Cornwall in rocks; and in loofe !l:ones in the gravel near Drayton in Shropfhire, !n the road towards Newcaflle. If thefc p:trts of the compofition be lefs rliflinCl:, or if vnly two of them be vi~ble to the eye, it is termed porphyry, trap, whinflone, moor!l:one, nate. And if it appears in a regular angnlar form, it is called bafaltes. · The affinity of thefe bodies has lately been f11rther well cflablilhed by Dr. Beddoes in the Phil. Tranf. Vol. LXXX. Thcfc arc all ellecmed to have been volcanic procluClions that have undergone different degrees of heat; it is well known that in Papin's di ge!l:er water m;.:y be made red hot by confinement, and will then diflolve many bodies which otherwife arc little or not at all aCled upon by it. From hence it may be conceived, th:lt under immenfe preffurc of f11perincumbent materials, and by great heat, thefe m:lffes of lava may have undergone a kind of aqueous folution, wi thout any tendency to vitrifaClion, and might thence ha~e a power of cryflallization, whence all the varieties above mentioned from the different proportion of the materials, or the different degrees of heat they may have undergone in this aqueous folution. And that the uniformity of the mixture of the original earths, as of lime, argil, filex, magnefia, and barytes, which they cont:~in, was owing to their boiling together a longer or thorter time before their elevation into mountains. See note XIX. art. 8. The feat of volcanos feems to be principally, if not entirely~ in thefe firata of granite; as many of them are fituated on granite mountains, and throw up from time to tim~ thtets of lava which run down over the preceding llrata from the f:tmc origin; and in this they feem to differ from the heat which has feparated the clay, coal, and fand in moraiTes, which wou!J :~ppear to have rifcn from a kind of fermentation, and thus to have pervadetl the whole mafs without any expuition of la\'a. All the lavas from Vefuvi11s contain one fourth part of iron, [Kirwan's Min.) and all the five primitive earths, Yiz. calcareous, argillaceous, fi]iccous, bar) tic, and magnefian earths, whtch are alfo evidently produced nc,w daily from the recrements o£ animal and vegetable bodies. What is to be thence concluded? Has the granite t1ratum in very antient times been produced like the prefent calcareous and llliceous malies, according to the ingenious theory of Dr. Hutton, who fays new continents are now forming at the bottom of rhe fea to rife in their turn, and that thus the terraqucous ~lobe has been, :.tnd will be, eternal! Or fltall we fuppofe that this internal heated· I |