104 



THE NULL AM ULLAYS, 



which thick deltas of sand have been formed, with their steep 

 shore-edges just in a line with the edge of the flooded 

 river. 



As it was, we saw the true channel of the Kistnah 

 throughout this part of its course which, except for a rapid 

 here and there, is often cut, like a canal, in the nearly hori- 

 zontally-bedded quartzite rocks. In one case, we walked 

 along a reach of smooth water for nearly six miles, as it 

 flowed in a vertical-sided channel. The other reaches were 

 also tolerably long ; and at no points were the rapids of 

 much length. 



The rock- exposures in this river bed are wonderful. 

 Looking at the way the beds lie ; at say 5° east-south-east, 

 we must have walked, on one occasion, over the successive 

 edges of at least 2,800 feet of quartzite beds, all fairly exposed. 

 One might almost reckon the height of some of the hills to 

 the north at sight, as the outcrop of beds from the river 

 is seen contouring along the valleys and up the slopes to 

 near the crests of these hills. And nearly all these miles 

 of rock-surface are polished and varnished, as it were with 

 a coating of black-lead ; the combined action of the river 

 and atmosphere having formed on the surface of the usually 

 white and buffish- colored rock a deposit of peroxide of 

 iron. The smoothing and polishing are easily accounted 

 for, but it is extraordinary what little effect this long-con- 

 tinued wear-and-tear has had in rubbing down the edges 

 of the outcropping quartzite beds. These have almost lost 

 their ordinary sharpness of angle, it is true, but they are 

 as square as on the day they became exposed. 



Towards Yeerabudr the river bed becomes a perfect 

 museum of true geological effects : as they are seen in the 

 way the rocks are lying, the form into which they have 

 been worn do^ 7n ; their constitution, and the manner in. 



