[ 57 ] 



author means that mofl: or all calcareous mountains were fortiied 

 in the fea, this will not be difputed ; but if his meaning be, 

 that all calcareous matter confifts of marine exuvise, this cannot 

 be allowed, as huge, mafles of marble exift which difcover not 

 the' leaft trace of marine exuvia, and calcareous fubftance is 

 found in many granites and the component parts of granite, 

 which was never fufpedled to be of teftaceous origin. The exift- 

 ence of fuch maffes is not difputed by our author. " There are 

 " (fays he) in all regions of the earth, huge mafles of calcareous 

 " matter, in a cryftalline or fparry fiate, in which, perhaps, no 

 " veflige can be found of any organized body, nor any indication 

 " that fuch calcareous matter had belonged to any animals, but 

 " as in other mafles this fparry flrucfture or cryftalline fl:ate is 

 " evidently aflumed by the marine calcareous fubftances in oper- 

 " ations which are neccfl"ary to the confolidation of the ftrata, it 

 " does not appear that the fparry mafles in which no figured body 

 " is formed have been originally different from other maflTes 

 " which leave ample evidence of their marine origin." That is to 

 fay, fince fparry mafles arc found among calcareous fl:rata of 

 teftaceous origin, other fparry maflTes may alfo have the fame 

 origin. This reafoning does not appear to me at all conclufive, 

 any more.than if an inhabitant of the interior parts of a continent, 

 itnacquainted with any calcareous flones but thofe of a fparry 

 fl:ru<5lure, fliould conclude that all this matter originally proceeded 

 from the bones of land animals, becaufe they alfo are of a calcareous 

 nature. It is much more probable that fea animals themfelves de- 

 rive their calcareous matter from a pre-exifting fubftance of the fame 

 nature contained in their food, as we have no proof of the adlual 

 Vol. V. H produ(5libillty 



