of the Scmthern Mahratta Country. 106 



veins of quartz ; and, what is curious, there are numerous small 

 vesicular cavities throughout the felspar, some of which are 

 lined with very minute crystals, apparently of chlorite. It would 

 be interesting to ascertain the exact relation which this rock 

 bears to the granite, a jwint which I myself had not an oppor- 

 tunity of examining. 



A very beautiful rock is found associated with the granite at 

 Gudjunderghur. It is a sort of greenstone porphyry; the 

 basis being greenstone, and containing large crystals of red fel- 

 spar. 



The Indian granite is generally small granular. I have only 

 seen one specimen of large-grained granite in India, which had 

 been brought from Mysore, and was composed of felspar, quartz, 

 and mica. 



At the Falls of Garsipa there is a variety of granite, which 

 differs from the common granite of India. It is not so old a 

 granite as the latter ; is composed of small grains of white fel- 

 spar, quartz, and mica; has, in some instances, a slaty appear- 

 ance; and is associated with gneiss and hornblende schists. 

 These rocks, being perfectly bare, can be very easily examined. 

 They all occur within a space of a few hundred yards. I ob- 

 served several varieties of the hornblende rock. One consists 

 almost entirely of hornblende ;. a second contains disseminated 

 crystals of felspar ; a third contains mica and felspar ; a fourth 

 has more of the characters of actynolite than hornblende ; and a 

 fifth contains so much mica, that it appears to be almost entire- 

 ly composed of it. All these varieties, with the gneiss and gra- 

 nite, pass insensibly into each other. They are distinctly stra- 

 tified ; have a dip of about 30° ; and their direction is nearly 

 ESE. They form the sides of the chasm, over which the river 

 is precipitated at the Falls of Garsipa ; and the depth of which, 

 as already stated, is nearly 1000 feet. This is the only place 

 in India where I have met with primitive gneiss ; but it is not 

 improbable that it occurs in many other parts of the country. 

 We are told by Dr Davy, that the greater part of Ceylon is 

 composed of it ♦ ; and it is also found in the Hymalayas t. 



• Vide Transactions of the Geological Society of London, voL v. p. 314 

 ^ Vide do. da New Series, vol. i. p. 132. 



