Chap. XI.l cuddalore sandstones. 165 



Chaptee XI. — Guddalore Sandstones. 



With the exception of tlie alluvial deposits, the formation which I 

 Extent of the forma- ^^^® termed the Cuddalore sandstones is the most 

 ^^^' recent sedimentary formation in this part of the 



Carnatic. It overlies all the Cretaceous rocks to the Eastward, and 

 probably extends both in a North and Southerly direction beyond the 

 limits of the area herein treated of. Beds similar in lithologic character 

 and classed by Newbold with this formation, are also met with in the 

 neighbourhood of Madras, and, according to Newbold, to a considerable 

 extent in the low country still farther North. The same formation also 

 extends to the South of Tanjore, though of its limits in that direction 

 we are ignorant ; and it is, moreover, a question for future consideration 

 whether parts of the lateritic deposits of the low country of the West 

 Coast be not of equivalent age to the sandstones of Trivicary and 

 Cuddalore. 



The area occupied by this formation is more elevated than any 

 Characters of the sur- P^^^^ ^^ ^^^ surrounding country. It is generally 

 ^^^®- covered thickly with a ferruginous sandy soil, 



known as '' lal," or red soil, and as, from its elevation, it is dry and but 

 rarely capable of irrigation, the greater part of it is abandoned to 

 jungle, which in some parts is very dense, although of stuated growth. 

 The rocks are only seen at rare intervals, chiefly on the edges of the 

 elevated ground, which is frequently bounded by a little escarpment 

 such as that figured in Plate II. (frontispiece.) The formation consists 

 in a great measure of grits and sandstones : thin beds of clay are 



occasionally intercalated, but are rare; and the 

 Mineral character. . . , 



whole formation is characterized by its ferruginous 



character, the sandstones, clays, &c., being tinted of all hues of yellow, 



