1002 Notes, chiefly Geological, across the Peninsula. [No. 156. 



phyry. As anticipated, the laterite was found capping a ridge of trap 

 and vvacke a little to the S. W. of Ingleswara presenting a similar deve- 

 lopment of the lithomarge near the line of contact with the trap as ob- 

 served at Beder. The latter rock passes into a friable greenish wacke, 

 and also into a dark amygdaloid containing spheroidal cavities, often 

 filled or lined with green earth. 



The hill of Ingleswara, marked by an old tower, is principally com- 

 posed of wacke penetrated by flattish, apparently compressed, veins of 

 fibrous arragonite. On the top of the hill are scattered globular and 

 angular fragments of basaltic trap ; while partially imbedded in 

 the soil covering its sides, are rough, scabrous-looking blocks of a 

 light coloured rock, resembling altered limestone passing into chert. 

 These blocks are mostly angular, from generally 6 inches to two feet 

 thick, have a whitish exterior so rough in aspect and touch as, in these 

 respects, to resemble trachyte, and when fractured the small glistening, 

 red, and white calcareous crystals they imbed, might at first sight be 

 taken for those of glassy felspar, The softer and more crystalline 

 portions of this singular rock effervesce with acids. It occurs also, in 

 detached blocks, on the wacke at the base of the laterite cliffs S. W. 

 of Ingleswara. The rock here is more compact, homogeneous, less 

 crystalline in structure and exhibits dark dendritic delineations. Some 

 fragments are partly coated with a thin bluish white enamel, which is 

 apt to assume a botryoidal form ; on its surface are seen numerous small 

 white globules of white enamel. Among the lateritic debris intermin- 

 gled with these blocks are interspersed numerous nodules of a black cine- 

 ritious looking mineral, containing cavities filled with an impure, 

 earthy, brown manganese ; their black outer crust is often so indurated 

 as to give fire with steel. Before the blowpipe, per se it reddens slightly 

 and exhibits minute globules of a bluish white enamel. 



The following section will exhibit the position of these blocks of 

 cherty limestone as they occur on the sides of a valley of denudation 

 and excavation, a mile in width. {Plate Diagram No. IV.) 



A. Laterite, overlying trap at B. and stripped off at E and B. b. 



B. B. b. Trap. 



C. Globular basaltic trap. 



D. D. Blocks of whitish scabrous limestone passing into dust and 

 half imbedded in lateritic gravel. 



E. Valley of denudation and excavation. 



