92 GLACIOLOGY 



the direct rays of the sun a re-freezing process has set in, long acicular needles of ice 

 forming from the small grains of gravel and crossing and recrossing in the most 

 beautiful patterns. In others we saw hexagonal plates being formed on the surface 

 of the water, as well as the needles radiating from the sides and bottom. The last 

 quarter or half mile of our day's sledging we have been passing over and through a 

 series of streams which cover the ground almost without intermission for the whole 

 distance, and it was only by treading on the tops of the ablation ripples that we 

 were able to keep dry, and even with that precaution we succeeded but indifferently. 

 To the roar of rushing water which we heard from the ice-cliff now succeeds the more 

 insidious trickle of the thousands of streams which are steadily finding their way by 

 devious paths over the convex face of the glacier to join the main streams below. 



Late in the evening of the 21st of December we walked down to the edge of the 

 glacier just at the corner made by the isthmus joining the Solitary Rocks to the 

 mainland. At the corner of the glacier bulge, and below the granite isthmus, was 

 a lake which was fed by at least four streams from a large hanging glacier opposite. 

 These streams we could see from our position were yellow with silt, and a very large 

 amount of fine detritus must be carried into the lake and on into the New Harbour 

 Dry Valley by the stream which has its origin in the lake. A fifth stream of water 

 could be heard flowing underneath us from one side of the Solitary Rocks, and in- 

 numerable tributary streams were flowing over the face of the glacier cliff". By the 

 night of the 21st the 2 inches of snow which fell during the 19th and 20th had 

 either been removed as thaw-water, or left as a thin coating of rough ice, opaque 

 through the inclusions of air ; and the ablation-rippled surface has been much 

 intensified, the ripples being converted into ice-waves, with several inches difference 

 between the top of the sharp crest and the bottom of the trough." 



When we awoke on the morning of the 22nd a strong cold breeze was blowing- 

 down through the gullies leading from the inland plateau, and this breeze continued 

 until the 26th. The thaw practically ceased when the breeze sprang up (except in 

 those districts locally affected by heat-radiation from the rocks), and no further 

 remarkable evidences were noted until the last stages of our return down the glacier 

 valley. 



During this gale ablation and the removal of snow by drift were very rapid, and 

 the patchy snow-drifts passed on our way up had been lai'gely reduced in size before 

 we passed them on our way down the valley. Many, indeed, had been entirely re- 

 moved, and the only evidences of their former occurrence were the corresponding 

 patches of ice free from ablation ripples. The thick drifts piled against the southern 

 side of the bluff" under the peaks Dj, D^, and D3, Ferrar's report, had had at least 18 

 inches of its upper surface removed, and sastrugi a foot or more high had been 

 evolved. 



Another effect of the quick change from thaw to cold wind was the formation of 

 a fringe of outstanding feathery ice-crystals along the margin of many of the open 



