of a Route from Madras to Bellaiy, in 1 822. 36 1 



when it suddenly altered to green ; and this colour subsequently 

 seemed to be constant in all the plains and low grounds. The 

 general direction of the strata of clay-slate corresponded with 

 that of the ranges of mountains which they composed ; viz. 

 about north-north-west and south-south-east, with a very great 

 dip to the north-east; all the associated rocks being conform- 

 able, unless the sandstone-caps should be an exception, which 

 appeared to have a very slight dip, if the appearances noticed 

 from Curcumbaddy and Nundialpett may be considered as 

 indications of it. However, of the latter I had few favourable 

 opportunities for examination. 



The strata of clay-slate appeared sometimes to be nearly 

 vertical ; but the exact dip was never measured. 



The same dip and direction of the strata were exhibited in 

 the fourth division, of clay-slate. 



Of the rocks associated with clay-slate, the more important 

 and general were sandstone, hornstone, calcareous schistus, 

 flinty slate, and quartz. Calc-tufa, and marls of infinite variety 

 of colour and induration were also found nearly throughout, 

 and in some places in extraordinary quantity. 



The sandstone was usually found on the summits of the hills ; 

 the calcareous schistus and flinty slate in the valleys; the quartz 

 forming veins and layers in the seams of the clay-slate, and 

 appearing therefore only where the latter was not concealed 

 by alluvial depositions. 



These were sometimes found all together ; but it may be 

 more convenient to consider each of them separately. 



The quartz was generally of a white colour, and the layers 

 of all degrees of thickness, from one tenth of an inch to one 

 foot and a half. It was extremely subject to disintegration, 

 covering the ground frequently in such quantity with its no- 

 dules, as completely to whiten it. These appearances were 

 particularly remarkable on the march from Curcumbaddy to 

 Baulpilly, from the vicinity of the hills on both flanks. After- 

 wards the valley opens, and the strata are generally concealed 

 by the soil ; but whenever rocks appear to any extent, quartz, 

 either in veins or layers, will almost invariably be found per- 

 vading them. It is very abundant in the clay-slate between 

 Nundaloor and Wuntimettah, and here rather remarkable 

 from containing numerous little nests of a kind of green earth ; 

 until, however, fifty miles north of Cuddapah, and clearing 

 the hills beyond Jungumpilly, the individual masses of quartz 

 are too inconsiderable in themselves, to serve in any other way 

 than merely as a characteristic of the clay-slate, and other 

 more important rocks. 



The march from Jungumpilly to Poornamila, with the ex- 

 New Series, Vol. 4. No. 23. Nov. 1828. 3 A ception 



