18440 Notes, chiefly Geological, across the Peninsula, fyc. 985 



verse river courses through the chalk escarpments of the weald, by the 

 elevatory forces that raised the strata to their present position. The 

 features of the original fissure have doubtless been modified by the 

 abrading power of the river; which, when swelled by the freshes 

 entirely fills the gap, about a mile in width, its sides rising rather pre- 

 cipitously from the river's banks. 



Beyond this ridge, which is of no great length, the surface of the 

 country appears flat as before, and the rise from the coasts scarcely 

 perceptible. With regard to the theory, of the tract between Bez- 

 warah and Condapilly having once formed the bed of an extensive 

 lake, my friend Mr. Malcolmson has justly observed, that, " a careful 

 survey of the hills from the summit shows, that they are short insu- 

 lated ranges, such as are found over the Circars and other tracts rising 

 from a level country ; and that had a lake existed in the plain above, 

 every slight rise of the river would have carried its waters round their 

 shoulders to the North and South." 



The gneiss composing the ridge of Bezwarah is garnetiferous, Clea- 

 velandite often replaces the common felspar, and renders the gneiss li- 

 able to decay. It contains large veins of quartz, and is intersected by 

 greenstone dykes, the presence of which may serve to account for the 

 distortion observable in its strata. 



A little to the N. E. of Bezwarah are the diamond mines of Mal- 

 lavelly where the gneiss is in some places covered by a conglomerate 

 sandstone, resembling the diamond conglomerate of Banganpilly and 

 Kurnool, and of which it appears here as an outlying patch. The dia- 

 monds are however dug for in a bed of gravel composed chiefly of 

 rolled pebbles of quartz, sandstone, chert, ferruginous jasper, conglo- 

 merate sandstone and kunkur, lying under a stratum of dark mould 

 about a foot thick. Dr. Benza traced the conglomerate sandstone hence 

 by Ellore and Rajahmundry to Samulcotah. 



From Bezwarah by Condapilly to the vicinity of the Warapilly 

 ghaut, the hypogene schists, chiefly gneiss and granite occur. East of 

 Warapilly these rocks are covered by the Northern termination of the 

 Cuddapah limestone beds. The diamond sandstone associated with 

 this limestone, stretches still further North as already mentioned, by 

 the diamond pit of Mallavelly to Samulcotah. 



A little North of Warapilly, granite and the hypogene rocks con- 



