1840.] 



from the Peninsula of India. 



21 



fracture granular crystalline. This stone is susceptible of a fine polish, 

 and might be employed with advantage in ornamental slabs for inscrip- 

 tions, vases, &c. It occurs near the line of contact with the schistous 

 chlorite, from which it probably derives its peculiar hardness and colour. 



39. Lim estone of Kurnool altered by contact with the schistous 

 chlorite ; colour, dull green, streaked with dark purplish ferruginous 

 bands ; fracture granular, sub-crystalline, extremely tough under the 

 hammer, effervesces feebly with dilute mineral acids. Some varieties 

 imbed pyrites and assimilate serpentine. It occurs at Kurnool, and on 

 the tongue of land between the confluence of the Tumbuddra and Kist- 

 nah rivers. 



40th.— Quartz rock of Darwar, coloured with iron, and containing 

 nests of decayed quartz and felspar, passing into kaolin, and often tinted 

 yellow, brown, and reddish by oxide of iron. In the hilly zone ex- 

 tending between Kittoor and Darwar, there is a variety that ex- 

 actly resembles the rock composing the upper portions of the cop- 

 per mountain and Sondur ranges, being of a jaspery and highly fer- 

 ruginous clay, sometimes passing into a true ore of iron, with a 

 cherty quartz in alternate layers, generally on their edges, and vary- 

 ing from the eighth part of an inch, to an inch in thickness. The lami- 

 nae are frequently contorted and bent, and impart a curious waved 

 or striped appearance to the rock. It occupies a similar geognostic po- 

 sition, and is seen generally cresting the slaty hills around Kittoor. Some- 

 times, as Christie accurately observes, the base of the rock is white or 

 grey, and traversed in all directions by dark brown-coloured veins, high- 

 ly impregnated with iron : but in some specimens, the dark brown variety 

 is in much larger quantity than the white basis ; and then the latter ap- 

 pears as if it had been broken into a number of small angular fragments^ 

 which had afterwards been united by the consolidation of the brown va- 

 riety from the fluid form. This variety contains numerous small cavities 

 which are lined with red haematite in the shape of stalactites, or having 

 a blistered, or mammillary form. The cavities are generally very sraaU. 

 This rock in petrographical structure and geognostic position, we may 

 safely pronounce to be identical with that composing the precipitous 

 sides of the Bimagundi pass into the Sondur valley (described at page 

 147 Journal No. 20) ; and associated with it, we find, near Kittoor, as at 

 Sondur, a magnetic iron ore with polarity, exhibiting a similar laminar 

 structure and a like tendency to split into rhomboidal paralellograms, 



41. — Breccia, of the old red sandstone formation of Christie, from the 

 north bank of the Malpurba, Southern Mahratta Country ; a reddish brown 



