1836.] 



Neelgherties and Koondahs, 



273 



some miles round, is bestrewed with blocks and pieces of magnetic 

 iron ore (No. 110); and, between this place and the moderately large 

 river further west, not only this species of iron ore, but the lateritic 

 kind also, are seen in numerous pieces on the soil. 



Four or five miles further west, just before fording the largest torrent 

 in this road, we see a small ridge of whitish rocks, not more than five 

 or six feet above the ground, formed by a thick bed of quartz rock, run- 

 ning in a direction E. and W., traversing the river, many of the blocks 

 jutting above its waters, and extending half a mile west beyond it. It 

 is a bed of granular, or rather columnar, quartz, containing titaniferous 

 iron, somewhat like the one in the Kaitee descent (No. Ill), although 

 the quartz is not so friable, nor the titanium so abundant. 



The waters about this ore seem strongly impregnated with iron; 

 since the rivulet, which runs near it, deposits in its course a good deal 

 of an ochreous earth, and the little pools of stagnating water, in its 

 vicinity, have the ferruginous irridescent film on their surface. 



The prevailing rocks are now hornblende slate and sienitic granite. 

 All the hills have a rounded contour, and, in the sections for the road, 

 the usual detritus of the decomposed rock is seen everywhere. In 

 some of the blocks near the Avalanche, the decomposition of the rock 

 into the first stage penetrates so deep, that, if the geologist is satisfied 

 by breaking a superficial piece from the mass, he may be led into error 

 regarding the composition of the rock. The pisiform iron ore is not 

 rare in all this tract of country (No. 112); I mean the conglomerate 

 resulting from the agglutination of rounded pieces of the heematitie 

 iron ore. 



In the bed of the river, about half a mile from the Avalanche bunga- 

 low, the masses imbedded are granitic, composed of four minerals, 

 felspar, quartz, garnets and hornblende ; this last being in some blocks 

 replaced by mica (No. 113). All the angular pyramidal masses 3 near 

 the bungalow, are of the same kind of granite (No. 114). 



Eastern Koondah Ghaut — Avalanche — Himigala Hills. — Leaving the 

 Avalanche bungalow, to go to the new road above it, and following the 

 path which descends from the stables, about fifty yards onwards, we 

 ford the rivulet which conveys all the waters collected in the large ravine 

 descending from the eastern Koondah pass. Crossing the field we see a 

 little knoll traversed by a basaltic dyke in an east and west direction 

 (No. 115); it is flanked by, and has burst through, sienitic granite 

 (No. 116). 



Crossing the road, and ascending the ridge opposite to the Avalanche, 

 this landslip comes at once to view. There has evidently been no sink- 

 ing of the land in the declivity of the hill, but it seems that a thick 

 stratum of the rock, lying nearly vertically on the declivity of the hill 



