54 GEOLOGY OF KEBEABASA. Chap. II. 



of rock are huddled in indescribable confusion. The drawing, 

 for the use of which, and of others, our thanks are due to 

 Lord Kussell, conveys but a faint idea of the scene, inasmuch 

 as the hills which confine the river do not aj>pear in the 

 sketch. The chief rock is syenite, some portions of which 

 have a beautiful blue tinge like lapis lazuli diffused through 

 them ; others are grey. Blocks of granite also abound, of a 

 pinkish tinge ; and these with metamorphic rocks, contorted, 

 twisted, and thrown into every conceivable position, afford a 

 picture of dislocation or unconformability which would gladden 

 a geological lecturer's heart; but at high flood this rough 

 channel is all smoothed over, and it then conforms well with 

 the river below it, which is half a mile wide. In the dry 

 season the stream runs at the bottom of a narrow and deep 

 groove, whose sides are polished and fluted by the boiling 

 action of the water in flood, like the rims of ancient Eastern 

 wells by the draw-ropes. The breadth of the groove is often 

 not more than from forty to sixty yards, and it has some 

 sharp turnings, double channels, and little cataracts in it. 

 As we steamed up, the masts of the " Ma Eobert," though 

 some thirty feet high, did not reach the level of the flood- 

 channel above, and the man in the chains sung out, "No 

 bottom at ten fathoms." Huge pot-holes, as large as draw- 

 wells, had been worn in the sides, and were so deep that 

 in some instances, when protected from the sun by over- 

 hanging boulders, the water in them was quite cool. Some 

 of these holes had been worn right through, and only the 

 side next the rock remained ; while the sides of the groove 

 of the flood-channel were polished as smooth as if they had 

 gone through the granite-mills of Aberdeen. The pressure 

 of the water must be enormous to produce this polish. It 

 had wedged round pebbles into chinks and crannies of the 



