350 THE LIFE OF JAMES D. FORBES. [CHAP. 



trast to the noble buttresses of the Jorasses and Tacul, 

 and the pinnacles of Le Ge'ant and Mont Mallet. The 

 lower termination is also quite unlike, for the glacier 

 spends itself on nearly level ground at the expansion or 

 embouchure of the valley which it occupies. And here 

 we have evidence of the immense fluctuations in dimen- 

 sion to which glaciers are subject within periods by no 

 means remote, probably more striking than is anywhere 

 to be found in Switzerland, not even excepting the case 

 of the glacier of La Brenva, on the south side of Mont 

 Blanc, which I have very fully illustrated elsewhere. 



' I made the best of my way on horseback across the 

 stony desert which separates the roadway from the foot 

 of the Nygaard Glacier, slanting towards its southern 

 edge. Dismounting, I scrambled along the moraine 

 bordering the ice, in company with the man whom we 

 brought from Ronneid, and who said he had been once 

 on the glacier before. I proposed to cross it from south 

 to north at a convenient place. This is always a matter 

 of some difficulty and uncertainty, and but for my 

 geological hammer, which I used to cut steps, we must 

 have abandoned it The character of the ice was very 

 highly crystalline, such as we find characteristically in 

 such glaciers as that of Aletsch which have run long 

 courses. The ice was very hard, rough, and sharp, pre- 

 senting many angular prominences ; and the sun glanced 

 from the plates of crystalline texture in a way which I 

 do not recollect to have seen so strikingly except in the 

 Swiss glacier just named. Farther, the general surface 

 of the glacier showed the gradual obliteration of the 

 more salient outlines, which I have particularly noticed 

 late in autumn on the Mer de Glace, and elsewhere, as 

 one of the most familiar and evident proofs of the 

 " plasticity " of the ice of glaciers on the great scale 

 the ridges between crevasses sink, the crevasses them- 

 selves are gradually cemented by the cohering of the 

 material of the sides bulging under their own weight 

 all the forms pass gradually from serrated into undula- 

 ting. This was so well marked on the Nygaard Glacier, 



