CHAPTER VIII. 



THE DECCAN TRAP IRON-CtAY (lATERITe) FORMATION. 



The group of argillo-ferruginous rocks, of which so many varieties 

 rp, 1 1 't occur in India, is one of the most difficult to deal 



should be restricted with, because SO much confusion has been intro- 



duced by the indiscriminate use of the term " laterite/'' a term good and 

 useful in itself, but which, in conformity with the rules of scientific 

 nomenclature, should be rigidly restricted to rocks of the same origin 

 as those to which the term was first applied by Dr. Buchanan, its in- 

 ventor. Doubts exist, however, as to what was the nature of the rock 

 he was treating of when he proposed the name in question. He de- 

 scribes it as " diffused in immense masses without any appearance of 

 stratification," and '' placed over the granite that forms the basin of 

 Malayala" — Malayala meaning the countiy in which the Malayalam 

 language is spoken, and including Travancore, Cochin, and Malabar. 

 He does not localize his description more closely when treating of the 

 subject in Chapter XII of his journey through Mysore, Malabar, and 

 Canara,^ a chapter which is headed " Through Panyain (Panyani) and 

 ,. , Central Malabar.'^ The laterite of Malayala, 



to certain sedimentary -^ ' 



deposits. Canara, and the Konkan is, from its very posi- 



tion, presumably of sedimentary (marine) origin, and this view is greatly 

 strengthened by the fact that not only are proofs found in parts of 

 the formation itselff of such sedimentary origin, but also by the fact 

 that, on the opposite side of the peninsula, beds occupying the same 

 relative position with regard to the present coast line (and which from 

 their geographical position may safely be regarded as mere extensions 



* Published in London, 1807, 3 vols., 4to. 



t e. g., at Cottayam in Travancore,— see Memoirs, Geological Survey of India, Vol. IV, 

 p. 258, note. 



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