CHAP. VI. TUFTED SNOW-CORNICES, 133 



spersed with numerous snow-beds overhanging one or the other 

 side in cornices. The thickness of the mists hindered progress, 

 and shortly before mid-day (being then about 17,000 feet above 

 the sea) we were brought to a halt. The clouds drifted away 

 for a few minutes, and we saw that although we might advance 

 perhaps two hundred feet higher we should not be able to reach 

 the summit.^ 



Two glaciers have their origin on the upper part of the 

 southern ridge of Illiniza. That which goes westwards, almost 

 from its commencement, is prodigiously steep, and is broken up 

 into the cubical masses termed seracs. The other glacier, de- 

 scending towards the east, though steep, is less torrential. The 

 two were united on the crest of our ridge, and over some cleft 

 in it there was a sheer, vertical wall of glacier-ice perhaps a 

 hundred feet high. We could see no way of turning it, and 

 there appeared no possibility of getting higher upon this side 

 except by tunnelling. But if we had passed this obstacle we 

 should not have reached the top of the mountain, for its extreme 

 summit was garnished with a cornice of a novel and very 

 embarrassing description. 



In the illustration at the head of this chapter two types of 

 snow-cornices are represented. That on the right of the engrav- 

 ing is common upon the crests of ridges near the summits of many 

 Alpine peaks, and in other high ranges, including the Andes. The 

 one upon the left I have seen only amongst the Great Andes of 

 the Equator, and for the first time on the summit of Illiniza. We 

 observed them again upon the lower peaks of Antisana, Cayambe, 

 Cotocachi and elsewhere. The formation of snow-cornices of the 

 more usual type is due to drift of the snow, and the icicles under- 

 neath them to the subsequent action of the sun ; and the process 

 of their manufacture, upon a small scale, can be observed upon 

 the ridges of roofs during any severe snowstorm. The other type 



1 The top was seen onl}? during these few minutes, and tlien became invisible 

 until we left the mountain. 



