158 GEOLOGY. 



is one of the smallest, although very interesting.^ It is 

 four miles long by three broad, and was found by Major 

 Goodfellow and a party of engineer oflS.cers, who sounded 

 it, to be 103 feet deep. As soundings were only carried 

 on over a small portion of the lake, this may perhaps 

 not be the maximum depth. The spot at which it 

 occurred was not far from the south-west shore, and 

 the bottom was found to rise in all directions around. 

 Its chief peculiarity is the absence of any perceptible 

 outlet whatever. To the west are high hills, to the east 

 a lower range. The lowest portions of the rim sur- 

 rounding the lake are to the north-east and to the south. 

 The latter, evidently the lowest of all, are about 150 feet 

 above the lake. 



It appears almost certain that the lake has a sub- 

 cast. If over British India the effects of marine to those of fresh-water 

 denudation in removing the rocks of the country be estimated at 1 to 100, I 

 believe that the results of marine action will be greatly overstated. 



Some years ago, before the question had assumed the present phase, before 

 «ven Colonel Greenwood's pamphlet had appeared, I remember being struck 

 by the absence of all signs of marine action and by the unmistakeable evi- 

 dence of immense fresh-water denudation in the Himalayas of Sikkim, where 

 ravines from 6,000 to 15,000 feet in depth are evidently the excavations of 

 the rivers running in them : so I am no new convert to a belief in the complete 

 efficacy of rain and rivers to produce gigantic effects. But after seeing, both 

 in India and Abyssinia, what the effects of these agents are in tropical coun- 

 tries, I do not feel surprised that their powers should be recognised with 

 diflficulty in regions where their effects are comparatively so dwarfed as in the 

 British isles, while the power of marine denudation is at its maximum from 

 the enormous coast line exposed and the small amount of detritus furnished 

 for its protection by rivers of small length, and in which floods are of excep- 

 tional occurrence. 



1 One of the principal geological questions which I had hoped to investigate 

 in Abyssinia is the mode of origin of one of the large African lakes, such as 

 Dembea. Unfortunately, I was unable to reach so far. 



