]'2 



Geology of the Country 



[July 



exfoliates in thick laminae, portions of which lay, like huge cubic 

 pieces, on the convexity of the rock. The quartz strata of this gneiss 

 are seen sometimes protruding some inches above the surface of the 

 rock, for the reason so often mentioned in the course of these Notes ; 

 here, as elsewhere, the gneiss contains nests of mica. 



Chinnapatam. — Along the road near Kingairee and Closepet, horn- 

 blende slate is the rock jutting above the soil (No. 39). The village 

 of Chinnapatam is situated in a plain, and being surrounded by a dry 

 ditch some feet deep, an opportunity is given of seeing the rock which 

 underlies the soil. 



In this ditch the lowest rock is gneiss, in many blocks the felspar be- 

 ing of a flesh colour (No. 40). This mineral, also, in veins, intersects 

 the strata of the gneiss, the surfaces of contact being tinged with a 

 green substance (chlorite ?) (No. 41). The stratification of the rock 

 is clearly seen in the walls of the ditch, where it is in a decomposing 

 state. 



The greater number of stones of the walls which surround the vil- 

 lage, the gate of the Fort, the several works, the door-posts and steps, 

 are all of this gneiss. 



On the outside of these walls, which are constructed without cement, 

 I found some pieces of a rock, which I am at a loss what to denominate. 

 In the few blocks I saw in the walls, the rock seemed unstratified, hav- 

 ing a porphyritic appearance. It is composed of red semi-foliated fel- 

 spar, approaching to compact, and glittering— penetrated by numerous 

 microscopic cavities, occasionally filled with a yellow clay, and con- 

 taining grains of perfectly transparent white quartz, some of them in 

 regular crystals of that mineral (No. 42). 



I was inclined to call it porphyry, but, having lately examined other 

 specimens from the same locality, in which the stratification of the 

 rock is quite evident, I forbear giving a name to it ( a). 



Mundium.— &\\ the rocks between Chinnapatam and Mundium, and 

 for some miles round, are hornblende slate, intersected in all directions 

 by numerous quartz veins, of divers dimensions and shapes. The soil 

 about the Bungalow is bestrewed with quartz stones and pebbles, chief- 

 ly angular, resulting from the breaking up of the quartz veins of the 

 hornblende slate. 



In the vicinity of Mundium I picked up some loose pieces of talc-slate, 

 mica slate, actynolite slate, induratedasbestos, green-stone, &c. (No. 41). 



(a) Since my examination of this rock I have read Mr. Hardy's remarks on the geo- 

 logy of the country in the route from Baroda to Udayopoor, &c. where he describes ap- 

 parently on analogous rock, but his is stratified, and he classes it among the varieties of 



granite. , ■ 



