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Show 32 NOTE XVI.-CALCAREOUS EARTH. IVhile Ocean wrap' d it in his azure robe. CANTO II. I. 34· FROM having obfervcd that many of the highe11 mountains of the world ~onfifl: of . a 1 · th £hells and that thefe mountains bear the marks of havmg been llme-llOne rep etc wt ' . . f he lobe. and as lime-fl:onc lifted up by fubterraneous fires from the mtenor parts o t g ' . . replete with !hells is found at the bottom of m:my of our deepefl: mmes, fome phi~Ofuphers have concluded that the nucleus of the earth was for many ages covered wtth water which was peopled with its adapted animals ; that the fhe\ls and bo~es of the:e animals in a long [cries of time produced folid fl:rata in the ocean furroundmg the an-ginal nucleus. . . Thefe fl:r::~ta confi11 of the accumulated exuvire of Odl-fill1, the animals penll:ed age after age, but their {hells remained, and in progreilion of time pro~uced t_he amaz111g quan t.I t.I CS 0 f J"11ne - 11on,•. which almofl: cover the earth. . Other m. anne ammals cal. led coralloids railed walls and even mountains by the cungenes of their calcareous ha_bJta-tions, thefe perpendicular coralline rocks make fome parts of the Southe~n Oce~n htghly dangerous, as ::ppears in the journals of Cap_t. Cook. From .contemplatmg the tmmenfe firata of lime-fione, both in refpeCl to the1r extent and thtcknefs, formed from thefe !hells of animals, philofophers have been led to conclude, that mu~h of the wat~r o~ the fea has been converted into calcareous earth by palling through thetr organs of digefl:IOn. The formation of calcareous earth feems more particularly to be an animal procefsas the formation of clay belongs to the vegetable economy; thus the iliells of crabs and other teflaceous fi01 are annually reproduced from the mucous membrane beneath them; the !hells of eggs are firt1 a mucous membrane, and the calculi of t!ole kidneys and thofe found in all other parts of our fyt1em which fometimes contain calcareous earth, feem to originate from inflamed membranes; the bones themfelves confifi of calcareous earth united with the phofphoric or animal acid, which may be feparated by diffolving the all1es of cakincJ bones in the nitrous acid; the various fecretions of animals, as their faliva and urine, abound likcwife with calcareous earth, as appears by the incruflations about the teeth and the fediments of urine. It is probable that animal mucus is a previous procefs towards the formation of calcareous earth; and that all the calcareous earth in the world which is fcen in lime-11ones, marbles, fpars, alabafl:ers, marls, (which make up the greateH part of the earth's crufi, as far as it has yet been penetrated,) have been formed originally by animal and vegetable bodies from the mafs of water, and that by thefe means the folid part of the terraqueous globe has perpetually been in an increating fl.ate, and the water perpetually in a decrealing one. After the mountains of {hells and other recremrnts of aquatic animals were elevated ,,bove the water the upper heaps of them were gradually diffulved by rains and dews and oozing through were either perfealy cryfl:allized in fmaller cavities and formed NOTE XVI. CALCAREOUS EARTH. 33 calcareous fpar, or were imperfectly cryllallizcd on the roof:s of 1"' ge. · · d . . . . .. r t cavities an pro-duceJ !lalaCl1tes; or tmxwg with other undiflolved {hells beneatl1 . . tl 1cm 1·o rmc J mar bl cs, w h1ch were more or lefs crvfial!Ized and more or lcfs pme · or ]a11 ly aft b · d'fT'l d _ , ll , er emg 1 a vc , the wate~ was exhaled from them in fuch a manner that the external parts became folid and formmg an arch prevented the internal parts from approach1'no each 11 r ' . ' b o ncr 10 ncar as to become fol1d, and thus chalk was produced. I have fpccimens of chalk funned at the root of feveral. flalaClites,. a~d in their ceutral p:lrts: and of other fialaCl.ites which are hollow like qllllls from a lmular caufe, viz. from the external part of th fl 1• n· h d · fl . c la .t~.:ute _ar enmg fir l by 1ts evapor~tion, and thus either attraCl:ing the internal difiolveJ par-ticles to the crull;, or preventing them from approaching each other fo as to form a folic! body. Of thefe I faw many hanging from the nrchcd roof of a cellar und th 1 · n ilreet in Edinbnrgh. er c 11g If this dilfulved limeftone met with vitriolic acid it was co11,,crt"d · t 1 b a ,.. . . . . · ~ 1n o a a <~Her, partmg at the fame time wJth 1ts fixable a1r. If it met with the fluor acid it b fl · f · h 1 r. · ccame uor; 1 Wit . t 1e uliceous acid, flint ; and when mixed with clay and fand, or either of them, ncqmres the name of marl. And under one or other of thefe forms compofes 2 great part of the folid globe of the earth. . Another ~ode in wh~ch Jimcflone appeilrs is in the form of round granulated par 4 t1cles, ~ut flightly_ cohenng togethc~; of this kind a bed extends over Lincoln heath, pcr~aps twenty miles ~ong by ten w1de. The form of this calcareous fand, its angleg hav111g been rubbed off, and the flatnefs of its bed evince that that part of tl . . ' le COUntry was fo f01 med under w~ter, the particles of fand having thus been rounded, like all other rounded pebbles. Th1s round form of calcareous fane! and of other larger pebbles is produced under water, partly by their being more or lefs foluble 1'n w te. d h . . a 1,an encet11 e angular parts become Jt!lolved, firfi, by their cxpofing a larger furface to the aCl:ion of the menfiruum, and fecondly, from their attrition aoainfi each other b th a . . b y e ureams or tH1es, for a great length of t1me, fuccc!Tivcly as they were colle.a.ed c1 h h fome of them had not acquired their hardefi fl:ate. ~..ot , an per aps w en 1 his calcareous fand has genernlly been called ketton-flone and believed to refemble th~ fpawn of fifh, it ~as acquired a form fa much rounder than fiJiceous fand from its be111g of fu much fofter a texture nnd alfo much more foluble in water. There are other fuft calcareo~s fl:ones ~al.led tupha which nrc depofited from ·water on moffes, as at _Matlock, ~rom wh1ch mofs It IS probable the water may receive fomething which induces It the readier to part with its earth. I_n fume lime-ll.ones the living animals feem to have been buried as well as their {hells dunng fome great convulfion of nature, thcfe !hells contain a black coal fub11 · h" h · . Y ance Wl.t Ill t em,_ 111 O~herS f~mC phJogiflon Or VOlatile aJcaJi from the lJocfies 0f the dead ammals remains mrxed wJth the flone, which is then called lil"er-11one as it emits a fidphurous fmell on being 11ruck, and there is a 11ratum about fix inches thick extends a cot~liderablc w~y over the iron ore at Wingerworth ne~r Chel1erficld in Dcrbyfhirc-, which feem~ evtdently to have becll formed from the £hells of frelh· water mufcles. E |