Remarks on Dr. Boase's Primary Geology. bb7 



7th. That the granitic and primary schistose formations are 

 only positions of the same continuous formation with a variety 

 of structure. 



Sth. That as masses of granite are found to occur insulated 

 and imbedded in the schistose formations, and connected with 

 the schists by the most intimate gradations of structure, 

 and mineral composition ; it is possible that all the granitic 

 formations, however extensive, may be merely imbedded 

 varieties in the schistose. 



9th. That the granitic rocks in the same continuous forma- 

 tion are found to present every variety of mineral composi- 

 tion, and although a particular mineral is found to prevail 

 in particular localities, that mineral composition cannot be 

 allowed to be a guide to the age or mode of formation of the 

 granitic rocks. 



I have shewn that Dr. Boase's 7th Inference derives 

 support from an examination of the association of the granitic 

 and schistose rocks of Mysore, and the idea expressed in the 

 8th Inference has often occurred to me as a subject of specu- 

 lation. It is supported by the insulated appearance of the 

 granitic mountain masses in the Bharramahal and in most 

 parts of South India; also from the globular concretions 

 of granite of which many granitic hills are formed, but the 

 evidence has appeared to me to be strongest in support of 

 the probability of the granitic formation of Southern India 

 being continuous in all its vast extent. 



In his 11th Chapter, the author gives a synopsis of the pre- 

 vailing theories regarding the nature and oirgin of the primary 

 rocks, which he thus concludes : 



" Having now given a general view of the prevailing theory 

 concerning the primary rocks, and having endeavoured to elucidate 

 the same by copious extracts from Lyell's « Principles of Geology,' 

 we proceed to point out those parts of the theory which appear to 



