336 Mr. B. Babin gt on’s Remarks on the . Geology 
rocks, especially on the east side, are frequently in sloping ledges, 
and some of the mountains themselves have steep sloping ledges 
also. Their decay leaves a whitish soil beneath the surface, I sup- 
pose from the quantity of felspar they contain. The dark particles 
of hornblende become ferruginous, and this is in general the top of 
the soil, which is reddish. Little fragments also become rounded, 
and in some cases, as at Bangalore, the whole is settled into the ferru- 
ginous stone mentioned as seen on the Malabar coast. In the de- 
tritus of these rocks, it does not seem that particles of felspar are 
washed away until they are decomposed ; on the contrary, water 
seems to percolate through the mass, and carry off the other con- 
stituents of the sienite, leaving the felspar in a decayed state in mass. 
Between Tompelly and Moolwagul there is much decayed rock. 
From Moolwagul to the top of the Moogly pass I travelled at night. 
This pass, down to the Carnatic, consists chiefly of a chain of wooded 
mountains, which run northerly and southerly ; and though the road 
passes up and down these for some miles before arrival at the lower 
land of the Carnatic, yet there is not a decided and continued de- 
scent except in one place. The rocks which compose these moun- 
tains I omitted to write a description of on the spot, so that they 
will be best known by an inspection of the specimens collected. 
The country below continues nearly as rocky as above : the low 
mountains run far beyond Chittoor into the interior, and rocks push 
up every where above the surface. Two great divisions of the rocks 
still continue, the one being the greenstone with a vein of quartz, 
the other the black rock. This latter, being found in particular 
places sticking up in blocks above the surface, I am led to believe 
runs sometimes in dykes or lies in beds. This seems of a more 
harsh feel than that which is found imbedded in the sienite, and it 
tends to split angularly, not concentrically. The composition of 
