1836.] 



between Madras and the Neilgherries. 



5 



The greatest number of the projecting rocks, and of the rolled 

 masses in the river close to the Bungalow, are granitic, both the com- 

 mon and the sienitic (No. 18). 



As I was anxious to pass the eastern Ghauts by day-light (the party 

 intending to pass in at night) I left Goriattum before them, and, as I 

 thought, early enough to reach the Ghauts before sun-set. 



Proceeding west, the country puts on a pleasing aspect, being inter- 

 spersed with hills andvallies, which relieve both the mind and the 

 eye from the wearisome sameness encountered before, and delights the 

 inquiring traveller, offering objects of scientific interest. 



Many hills and clustered masses of rock are seen in all directions ; 

 and on the convex sides of many of the former are placed saddle-shap- 

 ed, immense cubic masses of rock, the remainder, and more de- 

 pending portion, of the laminae to which they belonged, having been 

 hurled down into the plain. Others have these blocks, tor-like, on 

 their summits. 



Judging from the many rocks I examined near the road, all these 

 hills are granitic, the rock being traversed by thick veins of quartz. 

 Here and there in the plain I saw numerous pieces of quartzy magnetic 

 iron ore, so common in the south of India ; and in one place I saw an 

 immense bed of it projecting above the soil. 



Approaching Sautgur, numerous beds of a chloritic rock are seen, 

 sometimes porphyritic; and in other masses, the minerals being distri- 

 buted either in strata, or uniformly through the substance of the rock, 

 it becomes a protogine (No. 19). 



The clustered masses of rock in the plain, below the hills of Sautgur, 

 are of sienitic granite (No. 20), intersected, as usual, by thick veins of 

 quartz. When these veins happen to be found down the precipitous, 

 naked face of a hill, and in a direction perpendicular to the horizon, 

 the rock intervening between them decaying, these project above the 

 vertical surface of the rock, which appears as if furrowed, or fluted. 

 One of the hills of Sautgur has this appearance. 



This sienitic granite, besides the hornblende intermixed with the 

 other minerals, has nests of it formed of the pure foliated mineral, or 

 in a granular state, with some pieces of compact felspar, so as to resem- 

 ble hornblende porphyry (No. 21). 



All the plain below these hills is bestrewed with numerous pieces of 

 quartz and of foliated felspar, this last mineral being regularly crysta- 

 lized, and its surface shining when seen at an angle with the light 

 (No. 22). 



On both sides of the road are seen, nearly level with the soil, the convex 

 surfaces of large masses of a porphyritic rock, composed of regular 

 crystals of red felspar, hornblende and a lively pistachio coloured sub- 

 stance— (chlorite ?) (No. 23). 



