420 Notes, principally Geological, [No. 162. 



or seven miles per hour. In the dry season it is scarcely knee-deep, 

 and can be forded immediately above the Falls, with perfect safety, to 

 the opposite bank, whence a path, partly hewn in the rock, leads to the 

 basin and bed of the river below, impracticable or nearly so in the 

 depth of the monsoon. There are many other cascades in Upper Canara 

 seen glancing among the forest-clad heights of the Ghauts, but which 

 are approachable with difficulty during the monsoon, for instance, those 

 near Yellapoor, and Honeycoom, about three koss from Allawully. 



To have a true estimate of the beauty of the Falls of Gairsuppa, 

 they should be visited both during the monsoon, and when the water 

 in the river is so low as to admit of their being viewed from below. 



The rocks immediately beneath must present one of the most strik- 

 ing illustrations in the world of the eroding action of falling water, as 

 proved by the immense depth of the basin. To these must be added 

 the abrading effects of precipitated masses of rock. At the time of my 

 visit not less than 43,000 cubic feet of water, by rough calculation, 

 were falling per second into this vast rock basin. 



The precipice, over which the water falls, affords a fine section of 

 the gneiss and its associated hypogene schists, which dip Easterly and 

 Northerly away from the Falls at an angle of about 35°. The gneiss 

 is composed of quartz and felspar, with both mica and hornblende, 

 and alternates with micaceous, talcose, actynolitic, chloritic and horn- 

 blende schists, imbedding (especially the latter) iron pyrites. These 

 rocks are penetrated by veins of quartz and felspar, and also of a fine- 

 grained granite composed of small grains of white felspar, quartz, and 

 mica. Christie is of opinion, that this rock is not so old a granite as 

 the ordinary granites of India, and that this is the only locality in 

 India where he has met with primitive gneiss. No sound geological 

 proof, however, is assigned for this opinion. All the granites of India 

 are of posterior origin to the hypogene rocks, which they have invaded 

 and altered. Regarding the age of the hypogene rocks themselves — 

 always a most difficult problem to solve — we are still in the dark; 

 nor does the fact of this granite being associated with the so-called 

 "primitive gneiss," lead us to infer an origin more recent than the or- 

 dinary granites of South India. 



The mass of hypogene rocks has evidently been worn back several 

 hundred feet by the erosion and abrasion of the cataract ; the softer 



