1836.] 



A y eelgherric$ and Koondahs, 



Following the course of the river, within a quarter of a mile of 

 the waterfall, we meet with immense tabular masses, slightly con- 

 vex, of hornblende slate, scarcely above the level of the soil, over 

 the middle of which the water of the river flows. The strata are nearly 

 vertical at this place, and the water has cut a passage in them, making 

 a kind of trough. This has not been effected by the mere erosion of 

 the rock by the water, but by its displacement in the following way. 



The strata are vertical, and their direction seems in a line with 

 the course of the water, the action of which must tend to widen them ; 

 and this rock being intersected, as it is almost everywhere in these 

 hills, by numerous fissures perpendicular to the seams, square, rhom- 

 boid, or angular pieces, being loosened, are carried away, leaving the 

 space, occupied by the parallel strata, empty, and, therefore, trough- 

 like with parallel sides. But, although the formation of this oblong ca- 

 vity is chiefly owing to the cause above assigned, yet the corroding 

 action of the water, charged with pebbles and sand, is contributing like- 

 wise to the work of destruction ; since, this trough is a little wider at 

 the lower part than near the brim, on account of this part being 

 subject to the corroding action of the water the whole year round, 

 while the upper part is so only during the monsoon time. The dimensi- 

 ons of this excavation are the following : depth six feet — breadth, which 

 is uniform in all its length, six feet and a half — length, ninety two feet. 

 The rock as I said, in which this excavation is seen, is hornblende slate, 

 composed of hornblende, glassy felspar and a little quartz (No. 74). 



On arriving at the waterfall, the ledges forming the steps, down 

 which the water precipitates itself, are clearly stratified ; there are two 

 cascades, a very romantic parterre intervening between the two. It 

 seems that this last spacious ledge is formed by immense tabular masses, 

 or strata, placed in a horizontal position ; while those, which recede 

 perhaps a hundred feet back, and then rise abruptly two hundred feet 

 or more, forming the walls of the first fall, are vertical^ and in them 

 there is an excavation, similar to the one already described ; its depth 

 being ten feet, but its length not exceeding one half of the former J 

 specimen (No. 75) is from its side, which is the usual hornblende slate. 

 Among these strata, some are composed of two minerals, and some 

 arc entirely formed of hornblende ; while it is not rare to find some of 

 felspar alone. In all these cases, the strata are intersected by veins of 

 quartz, and, judging from the appearance at a little distance, it seems 

 that the precipitous sides of both the hills, forming the gorge facing 

 \ Koonoor through which the cascade falls, are of the same slaty foi> 

 \ matron as the masses of the waterfall. With the exception of some 

 i -basaltic boulders, implanted in the soil at the summit of the left hand 

 I hill, I saw no other rock in the vicinity of this cascade (No. 76). 

 | The rock which prevails in the Kaitee range, as well as in other places, 



! 



