chap, ix GEIT BIDGE 129 



and splitting frost loosen and crack the slabs into a mere 

 slope of debris, all rotten and ready again to split and resplit. 

 Sodden snow and trickling water rapidly produce immense 

 quantities of mud, which partly support, partly carry down 

 the stones that are not reduced to powder. On hot or wet 

 days streams of this stuff, small mud avalanches, in which 

 the mud predominates over the stones, trickle down the 

 slopes, and either reform on gentler slopes below, or flow 

 on to the surface of some glacier. In the latter case they 

 are carried down, and ultimately either shovelled off the sides 

 and end to form astonishingly large masses of boulder-clay, 

 or dumped into the stream and carried straight away to fill 

 the estuary at the river's mouth. 



This day was really hot. The sun shone with sensible 

 power, and all the land felt its force. The snows had now 

 been subjected to its dissolving action without cessation for 

 all the four-and-twenty hours of three consecutive clays. 

 What melting had thus been accomplished may be readily 

 imagined. One could see the snow-beds growing smaller. 

 Whole white hill-sides became brown between sleeping and 

 waking. Brown slopes with no more snow above them dried 

 into grey cakes. Bog-slopes facing the sun steamed like hot 

 potatoes. Every water-course was swollen to its full capacity, 

 and the brooklets of the previous week were channels dim- 

 cult to wade. We discovered this to our cost when within 

 Delta Valley its river had to be crossed. It was a raging 

 torrent between ice-banks which it undermined. For some 

 distance there was no point where a passage could even be 

 attempted. A division in the valley was reached, where the 

 stream unites two almost equal branches, one coming 

 from the col leading to Brent Pass, the other from a glacier 

 basin between Mounts Lusitania and Marmier, the explora- 

 tion of which was the day's aim. The first branch had to 

 be crossed ; it seemed no shallower than the united torrents. 



I 



