TRANSITION ROCKS. ^''^ 



however, that I have purposely confined myself to the exam- 

 ples of the relations which exist within my own knowledge, 

 between the Transition rocks and Granite. The same pheno- 

 mena are familiar, where gneiss and mica-slate come in contact 

 with that rock ; but as these strata are considered to be ot a 

 very different age, the facts which I might have cited, had my 

 object been to prove the age of granite with respect to all 

 other rocks, were unnecessary, when my purpose was to point 

 out the relative ages of killas and granite. 



From what I have said, I consider myself warranted in fi- 

 nishing this paper with the following conclusions : 



The Killas of Cornwall belongs to the Transition series of 



Werner. 



The Granite of Cornwall is possessed of every character by 

 which the Oldest varieties are distinguished. 



That Granite, the nucleus round which Werner conceives 

 all other rocks were deposited, is in some cases actually of a 

 later date than the Transition series, which comprehends strata 

 containing shells ; and that its subsequent formation is clearly 

 evinced by the appearances at St Michael's Mount. 



Hence, that the distinction of Transition rocks, is grounded 

 on false conclusions. 



And finally. That Werner must make very material altera- 

 tions on his present system, if he wishes to accommodate it 

 to the phenomena so commonly presented in nature. 



R 2 APPENDIX. 



