56 TOPOGBAPHT. 



the tributaries of the Bowany river in the Koondahs ; and 

 there is a considerable fall or weir, in the Pycara river. 



The soil of the HUls is exceedingly rich, and covered with a 

 short close green sward, which is maintained in a constant 

 state of verdure by the abundant supply of moisture. 



The Bowany river takes its rise in the Koondahs, flowing 

 through a deep fissure till it reaches the S. W. angle of the 

 range, when it makes a sudden turn to the eastward. It is 

 joined by a great number of tributary streams, each of the 

 lateral valleys having its own brook of beautifully limpid 

 water. Several of these rise within a few feet of the edge of 

 the precipice, bordering the hills on the west ; but with 

 scarce an exception all flow to the eastward. The edge of 

 the Koondahs, towards Ootacamund, is broken into a number 

 of valleys nearly filled with wood, and interspersed with patches 

 of verdure. 



The steepness of the sides of the valleys on the Koondahs, 

 and the loose nature of the soil, has given rise to a number of 

 what are called in French eboulements, or earth avalanches, 

 the earth having slipped down in large masses, leaving a cir- 

 cular vacuity in the edge of the hill above. One of the most 

 remarkable of these took place about 33 years ago, and is easily 

 recognised at the distance of 12 or 15 miles ; it is close to the 

 point at which the new road ascends the Koondahs. The 

 cause was probably the bursting of a water-spout immediately 

 above the spot, the earth having been in all probability pre- 

 viously loosened by the filtration of water through the sub- 

 jacent strata. 



Towards the lower part of the valleys, which is still encum- 

 bered with rocks, trunks of trees, masses of earth, &c., a chaly- 

 beate spring is found issuing from below the debris, and ming- 

 ling with the rivulet, to which it imparts an ochrey tinge. 



