242 KING: KADAPAH AND KARNUL FORMATIONS. [PART II. 
The Yellaconda mountain-ridge is for the length indicated, viz., 
Southern Yellaconda HOM about the parallel of Porenaumla down 
beds. to the Rawpoor-ghat, mainly made up of these 
quartzites. They are generally grey, white, or buff sands and grits 
in thiek beds, very compaet, vitreous, and in some bands, particularly 
the lower, rather waxy looking. Intercalated with them are thinner beds 
and flags, and there are occasional thin bands of slates and slaty flags. 
No conglomerates were observed of any importance. The beds are 
dipping to the eastward, regularly all down the range, at various angles, 
though the average 1s about 30^; and they are overlying a decided band 
of brown and green talcose slates. There is some undulation in the 
beds more particularly on the eastern slopes of the ridge. "Towards the 
Penn-air river on the north side, the highest beds exposed in the lofty 
mass of Pedda Mallam Conda are nearly horizontal, thus giving some 
fine scarps on the eastern face of the mountains. 
North of the Penn-air, the thickness of the quartzites now left 1s 
well displayed, and there must be at least 800 or 
900 feet of them. South of the river, they are 
at a much lower level in the hills; and there is no distinct evidence 
Thickness. 
of subjacent slates on the western slopes. 
On the eastern side of the range the base of the slopes is an exceed- 
E ingly wide deposit of broken and somewhat rounded 
by talus. debris of quartzite; the greatest width of this talus 
being 1۶ miles, without any rock being seen în situ. Consequently 
it is, on the whole, almost impossible to conjecture what kind of junction | 
there may be hidden beneath between these quartzites and the gneiss 
which lies outside the talus. There are frequent cases of the two different 
serles of rocks being traceable into almost immediate contact; and 
then the Yellaconda quartzites are dipping at high angles at the gneiss. 
In such cases, there has been faulting; for the 
Faulted. 
beds thus brought abruptly against the erystallines 
