of a Route from Madras to Bellary, in 1822. 439 



of the nulla at Tungtoor, where it was quarried for building, 

 the limestone was of a dull brick red, and frequently also va- 

 riegated with stripes and shades of a light gray or white. 



In approaching Banaganapilly, and all about that town, the 

 limestone was in great abundance, and its colour blue of dif- 

 ferent shades, but chiefly dark. The deposition of soil on 

 these plains afforded only a few opportunities of examining 

 the limestone; but, where visible, the strata seemed to be 

 nearly horizontal. These varieties, especially the last, were 

 very compact and fine grained, and with rather a conchoidal 

 fracture. The fine village of Banaganapilly, and the cele- 

 brated diamond deposit, is situated near the base of a low 

 range of tabular land, running about north and south, and 

 forming the western boundary of the great limestone field just 

 described. The range is here abrupt and precipitous, and 

 very irregular and broken in its outline, running out into 

 headlands, as well as having deep narrow valleys penetrating 

 far within it to the westward. 



Banaganapilly lies under the point of one of these promon- 

 tories, which projects five or six miles from the main range. 

 These hilly tracts form the fourth division, or second of clay- 

 slate, but, perhaps, do not terminate that of the limestone ; 

 for, although the depth of alluvium in this narrow valley is so 

 great as to conceal all rocky strata, yet, from the numerous 

 nodules of limestone on the surface, and the amazing depth 

 and extent of the depositions of calcareous tufa, and the re- 

 appearance of strata of limestone some miles east of Jeldroo- 

 gum, which then continue, with little interruption, even on to 

 the table land three or four miles west of that village, it is not 

 improbable that a connection subsists throughout. With ex- 

 ception of the cap, which is of sandstone, and which has al- 

 ready been adverted to, the whole mass of land forming the 

 right hand boundary of the valley commencing near Banaga- 

 napilly, and extending to Jeldroogum, appears to consist of 

 clay-slate nearly to the summit. There appeared to be table 

 land also to the left, or south, and which, I imagine, also to 

 be covered with sandstone (the Banaganapilly promontory I 

 ascertained to be so, by ascending three or four miles to the 

 west) ; but the immediate boundary of the valley on this side, 

 although, like the former, composed of clay-slate, instead of 

 a sandstone cap, was crested in its whole length with a sharp 

 black ridge of trap rock, formed of loose blocks piled upon 

 each other. 



The apparent base of the trap observed a pretty uniform 

 level ; nor was the ridge of much depth, the peaks, merely by 

 rising somewhat higher occasionally, giving the bed an ap- 

 pearance 



