310 KING: KADAPAH AND KARNÜL FORMATIONS. 
gradually increasing their dip till they pass under the slates (4). The 
limestone is much obscured by cotton soil, so 16 cannot be decided 
whether the thiekness of the limestone has been here exaggerated by 
faults repeatedly bringing up the same beds to the surface. From the | 
boundary between the limestones and the slates the ground rises steadily 
up to the top of the Venkatayapalem hill; and along this rise there 
appears an unbroken and nearly perfect succession of all the slates 
and quartzites recognized further to the north. The general lithological 
features of the different beds are not different from their appearance 
elsewhere. The limestone (/2) does not here accompany the slates (F) ; 
but an extra bed of gritty quartzite occurs in its place marked (5 a) 
in the section. The summit of the hill forms a small but striking 
plateau surrounded by a small scarp on all sides. It is capped by a 
dark reddish brown gritty sandstone which has been perfectly honey- 
‘combed with diamond pits. This gritty bed represents only the lower 
part of the great quartzite formation of the Pulichinta ridge, if it be 
regarded as the real representative of that formation, which seems rather 
a matter of fancy, for it might with equal propriety be set down as 
being the upper part of the (No. 6) diamond grit, separated merely by a 
rather unusual thickness of slates (vide Section III). Descending the 
hill to the east a line of fracture is crossed; and the gneissic rocks are 
found to abut against the horizontal (or nearly so) beds of slate (f). 
Near the centre of the valley is the village of Venkatayapalem, after 
which I propose to call this very singular trough between the two ridges 
of hills. The upheaval of the gneiss-area of this valley is remark- 
able for its great length and narrowness, and for the great height to 
which the intruded gneiss rocks were forced up. There is not the 
slightest trace of any of the once overlying quartzites, &c., to be seen 
on the gneiss, which rises in many places into great hummocky hillocks, 
some of which are not much under 100 feet in height. The southern 
end of the valley is thickly covered with a coarse shingle, chiefly made 
( لت ) 
