h 



, HUTTONIAN THEORY. 193 



1; 



Carrara marble does not diredtly originate from 

 to 5j ihells. 



cidj^ That nature has fome procefs, by which the 



k, above acid is feparated from the earth of bones. 



£ 



i^jj , and probably alfo from the earth of (hells, is 



evident from the flate in which the bones are 

 found in the caves of Bayreuth. Thofe that are 

 the moft recent, and leaft petrified, contain mofl 

 of the phofphoric acid. Where the petrifadion 

 has proceeded far, that acid is not found. 



171. Among many of the llrata, fuch a fluidi- 

 ty has prevailed, as to enable fome of the fub- 

 ftances included in them to cryftallize. Calca- 

 reous fpar and filiceous cryftals are often found 

 in ftratified rocks, forming veins of fecretion, or 

 lining clofe cavities, included on all fides by the 

 uncryilallized rock. In the inftances of srneifs. 



to 



ffflfiii 



pm; 



I 



3 



trik 



ml 



f 



and many fpecies of marble, almoft the whole 



matter of the ftratum is cryftallized. This 



. union of a ftratified and cryftallized llrudure in 



1^1 the fame fubftance, has a great affinity to that 



union of the cryftallized with the organic ftruc- 

 ture of fliells and corals which has juft been 

 mentioned ; and both are doubtlefs to be refer- 



^d red to the fame caufe. 



4 



y 



N Note 



