196 



Notes on Geological Specimens from 



[July 



seen, the country being flat, and covered with low jungle. Jaspers and 

 fragments of trap are found in the bed of the river, and the granite to 

 the north is intersected by numerous dykes of greenstone, usually run- 

 ning from S. E. by E. to N. W. by W. To the south of the river, 

 the country is lower, and for some way beyond the town of Daehapilly, 

 the limestone, usually dipping slightly to the south, continues to be 

 the surface rock ; which, whenever I have met with it, on the Kistnah s 

 at Cuddapah, near Auk, and the diamond mines of Banganapilly, and 

 at Tarputri in Bellary, or in the neighbourhood of the Wurdah, affords 

 the best indications of success to experiments inboring; copious springs 

 spontaneously rising from it, or being lost in the interstices between 

 its nearly horizontal strata. 



At Bezwarah, the river Kistnah appears to have cut a channel 

 through the short ridge of hills, which terminates on either side in 

 rather precipitous cliffs, and admits the stream into the great alluvial 

 plains extending to the mouths of the Kistnah and Godavery. Above,, 

 the country has much the appearance of having once been an exten- 

 sive lake, the bottom of which now forms the rich plain extending to 

 Condapilly to the N. W., and Munglegherry to the south of the river. It 

 is probably here, that Captain Herbert's correspondent observed that 

 the " hardness and composition of the rock appeared to differ, accord- 

 ing to the pressure they have been subjected to." I believe, that, spe- 

 cimens of the rocks of the bottom of the hill, have been sent to the 

 Asiatic Society by Dr. Benza, and that they are composed of the pecu- 

 liar gneiss of the coast. Felspar is common, and some of the varieties 

 possess considerable beauty. There are the remains of a rock pagoda 

 cut in a mass of compact felspar, above the road, leading along the 

 edge of the precipice over the river, portions of which have fallen, the 

 natural fissures of the rock exposing it to this kind of decay. On the 

 top of the hill the soft friable white rock, is found, and is carried 

 away by the natives for the purpose of whitening the walls of their 

 houses. It corresponds exactly with specimens from Vizagapatam, 

 described as gneiss by Heyne, and containing imperfect garnets. It 

 is not, however, either its site as lying above other rocks, or its ex- 

 posed situation, that has led to its decay, so much as the composition of 

 the ridge where the edges of the strata rise to the south. The strata 

 dip at a very considerable angle a little to the south of east. A care-' 

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

 insulated ranges, such as are found over the Circars and other tracts y 

 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 rise in the line of 

 bearing of the strata of the hill north of the river, and the appearance 



