344 CHARLES DARWIN 



my two companions discussing the cause; they had come 

 to the simple conclusion, " that the cursed pot [which was a 

 new one] did not choose to boil potatoes." 



March 22nd. After eating our potatoless breakfast, we 

 travelled across the intermediate tract to the foot of the 

 Portillo range. In the middle of summer cattle are brought 

 up here to graze ; but they had now all been removed : even 

 the greater number of the Guanacos had decamped, knowing 

 well that if overtaken here by a snow-storm, they would be 

 caught in a trap. We had a fine view of a mass of moun- 

 tains called Tupungato, the whole clothed with unbroken 

 snow, in the midst of which there was a blue patch, no 

 doubt a glacier ; a circumstance of rare occurrence in these 

 mountains. Now commenced a heavy and long climb, simi- 

 lar to that of the Peuquenes. Bold conical hills of red 

 granite rose on each hand ; in the valleys there were several 

 broad fields of perpetual snow. These frozen masses, during 

 the process of thawing, had in some parts been converted 

 into pinnacles or columns,* which, as they were high and 

 close together, made it difficult for the cargo mules to pass. 

 On one of these columns of ice, a frozen horse was stick- 

 ing as on a pedestal, but with its hind legs straight up in 

 the air. The animal, I suppose, must have fallen with its 

 head downward into a hole, when the snow was continuous, 

 and afterwards the surrounding parts must have been 

 removed by the thaw. 



When nearly on the crest of the Portillo, we were envel- 

 oped in a falling cloud of minute frozen spicula. This was 

 very unfortunate, as it continued the whole day, and quite 

 intercepted our view. The pass takes its name of Portillo, 

 from a narrow cleft or doorway on the highest ridge, 

 through which the road passes. From this point, on a clear 

 day, those vast plains which uninterruptedly extend to the 

 Atlantic Ocean can be seen. We descended to the upper 



* This structure in frozen snow was long since observed by Scoresby in 

 the icebergs near Spitzbergen, and, lately, with more care, by Colonel 

 Jackson (Journ. of Geograph. Soc., vol. v. p. 12) on the Neva. Mr. Lyell 

 (Principles, vol. iv. p. 360) has compared the fissures by which the 

 columnar structure seems to be determined, to the joints that traverse 

 nearly all rocks, but which are best seen in the non-stratified masses. I 

 may observe, that in the case of the frozen snow, the columnar structure 

 must be owing to a " metamorphic " action, and not to a process during 

 deposition. 



