Correspondence. 



291 



with Dr. Boase's work. " If my theory be correct, then the strata so 

 traversed by granite veins are not fossiliferous, but will be found at 

 some point to be distinct." Dr. Boase denies the generally received fact, 

 of the supposed graduation of fossiliferous formations into the prima- 

 ry schists. If, on the other hand, it be substantiated that the very 

 same beds with organic remains reach the granite, and at the parts 

 adjoining are metamorphised by the action of heat, then I am in 

 error. 



Dr. Boase doubts the correctness of the assertion, that rocks are 

 metamorphised by the action of heat when in contact with what are 

 called "igneous rocks," and he remarks, (Primary Geology, page 306,) 

 " Admitting these changes to have been produced by the action of in- 

 " tensely heated trap rocks, how comes it to pass that a like cause 

 "has not produced a corresponding effect ; how is it if these rocks have 

 " been intruded among the strata in a state of ignition, that they have 

 " not equally altered the same rock throughout their entire course ? 



I have alluded in several parts of my book, more particularly in the 

 last chapter, but more explicitly in the Annals of Philosophy, to a way 

 in which the generally received theory and mine may be recon- 

 ciled. Suppose my general views to prove erroneous, as in the above 

 instance, then I must admit that primary crystalline schists are only 

 secondary strata, changed by the action of heat ; but in so doing I 

 contend, that granite itself is in the same predicament ; that is, that the 

 whole of the primary rocks have then resulted by the action of fire on 

 fossiliferous strata. It may come to this, but in the mean time, the 

 facts are not sufficient to justify " our jumping at such a conclusion." 



Upon the investigation of the points on which Dr. Boase remarks, I 

 do not find that we have any published information as yet from the 

 examination of the vast primary formations of South India. The only 

 notice I am able to find, is a remark by Dr. Malcolmson, ( Journal of the 

 Asiatic Society of Bengal, No. 50,) where he remarks, that between 

 Hydrabad and Nagpore at the Meeklegandy Ghaut "limestone con- 

 taining shells was observed lying upon granite of a reddish colour ;" 

 but the observation is very imperfect, as it does not appear whether 

 the rock was part of an extensive granitic formation, or only a 

 portion of one of the granitic beds occurring in what I have termed the 

 " schistose series ;" neither does it appear, that Dr. Malcolmson endea- 

 voured to observe, whether the fossiliferous bed was traversed by veins 

 from the granite, or whether it was metamorphised in any way, or 

 changed in appearance or mode of aggregation, by association with the 

 bed of granite. 



