176 CRETACEOUS ROCKS OF S. INDIA. [PaRT II. § 2. 



frorn the sea ; which interval is occupied b}^ the shifting sands of the 



coast. . The base of the escarpment, as at present seen, is probably 



not less than 20 feet above the actual level of the water in the bay. 



General Remarks on the Oiiddalore Group. 



It will be seen from the foregoing description that the Ciiddalore 



sandstone formation must have been formed at a 

 Physical conditions of ..,.,„ 



country during Cuddalore period when the prmcipal physical features of 

 sandstone period. 



the surrounding country were much the same as 



at present, with the exception that a large part of the actual plains 

 of the Carnatic must have been below the level of the sea. The 

 perfectly undisturbed bedding and nearly horizontal position of the 

 underlying Arrialoor beds prove that since the middle of the Cretaceous 

 period, no great disturbance has affected the country in question, and 

 although more than one great elevation and depresssion has increased 

 or diminished the land area since that period, such changes were in all 

 probability equable and extensive in their effects, and were unaccom- 

 panied by local disturbance of a violent character. Under these cir- 



„ , cumstances "we might expect the Cuddalore for- 

 Probable extent of the ° '■ 



formation. mation to have been originally of considerable 



extent, and covering the greater part of the plains of the Carnatic, and 

 being the most recent formation, (of any thickness,) of which we have 

 any knowledge, we might expect to find other remnants than those 

 herein described scattered over the low country in question. 



Unfortunately we have no certain means of identifying the forma- 

 Difficulty of identify- '^io^ '^^ question. Its typical mineral character, 

 ^"^^ ^*' that of ferruginous grits, sandstones, and con- 



glomerates, with occasional beds of white clay, is no less characteristic of 

 many of the sedimentary formations of India, some of which can be 

 proved to be of very ancient date; and similarity of position, com- 

 bined with the negative indications of there being no proof of greater 

 antiquity, is the best evidence of identity obtainable. On such evidence 



