170 



ILLUSTRATIONS OF THE 



■ v> 



■ i\ 



/ 



■ i "- 



*- 



:> 





> 



t 



indeed than the Alps, but where the rock 



micaceous, talcofe 



fil 



to the hori 



d 



quartz 



Th 



fliell 



ous, in planes erei!}: 

 felled by veins of 



from Plym 



are fr 



a rock, that Wer 



would 



I think, admit 



to be truly primitive. Thofe from the lakes 

 alfo, are from the centre of a country, occu- 

 pied by porphyry, fchorl, hornftone-fchiftus 



d many oth 



ab 



th 



ord 



of 



hich 



there can be no difp 



It is true, that in this 



are 



trad th 



that might be 



g 



ft 



f the kind 



d 



termed 



were 



they 



nterpofed among thofe that are cer- 



nly primary ; and th 



y intermixture 



Ihews. how 1 



foundation there is for the d 



ftindion attempted to be made between the for- 

 mation of the one and of the other. If there is 

 any principle in mineralogy, which may be con- 

 iidered as perfedly afcertained, it is, that rocks 

 iimilarly ftratified, and alternated with one ano- 

 ther, are of the fame formation. 



r 



Hence we conclude, that there is 7io order of 

 Jlrata yet know?!, that does not contain proofs 

 of the exiftence of more ancient ftrata. We 

 fee nothing, in the ftricl fenfe, primitive. It 

 muft be underftood, that what is here faid has 

 no reference to granite, which I'do not confi- 

 der as a ftratified rock, and in which neither the 



remains of organized bodies, nor fand, have I 



beheve 



