358 Capt. Cullen's Notice of the Geological Features 



of Naggery, and which continuing near to the left of the road 

 as far as Woramallipett, then stretch off to the west, till they 

 are lost in the prolongation of the Tripetty range. The pe- 

 culiar features of the granite are very marked and conspicuous 

 in the whole of this western mass of hills, exhibiting itself on 

 their slope, in those great bare masses of rock, which are so 

 familiar to most people in this country, and on their summits 

 in enormous detached rugged piles and fragments. But what 

 contributes most powerfully to the interest of this part of the 

 route are these singular courses or dykes of trap rocks, which 

 may be observed crossing the country, without experiencing 

 the smallest deviation or interruption in their course from the 

 granitic barriers, which seem to oppose themselves on all hands 

 to their progress. 



Their deep black hue, and sharp, well-defined outline, con- 

 trasted with the light colour of the granite-masses, through 

 and over which they seem to pass, forcibly arrest the attention. 

 Granite appears also to a considerable distance on the right 

 or north-east side of the road, and probably constitutes the 

 greater portion of the very remarkable hill called Naggery Nose, 

 as I have traced it nearly to the foot of that hill. The hill just 

 mentioned, however, as well as those immediately to the north 

 of it, and whose outlines are equally singular, are evidently 

 capped with rock of a different nature. 



The caps, which occupy about one-fifth or one-sixth of the 

 whole height of the hills, are precipitous and mural on their 

 south and east sides, to the north sloping gradually off, until 

 they fall almost into the same level with the plains. I at- 

 tempted, both from Potoor and Woramullipett, to reach these 

 hills, with the view of ascertaining their composition, but the 

 distance was too great, and I could only approach their bases. 



Judging from the external appearance of the cap, it is com- 

 posed of two distinct rocks arranged in horizontal beds or 

 strata. The upper and lower portion of it appeared to be of 

 the same nature, being alike in colour, and marked by similar 

 numerous, but irregular vertical seams and fissures ; the effect, 

 probably, of decomposition. The aspect of the central stra- 

 tum or bed, was, however, different from either of those be- 

 tween which it lay. It was marked most distinctly through- 

 out its whole extent, by regularly parallel and horizontal 

 seams, which appeared to be those of stratification ; its colour 

 also, which was darker than the others, strengthening the sup- 

 position of its being a rock of a different nature*. 



The 



• I have since had an opportunity of examining the hills at Tripetty, 

 where both the cap and slope of the hills appeared to consist of but one 



rock. 



