344 
PORTILLO PASS 
CHAP. 
About noon we began the tedious ascent of the Peuquenes 
ridge, and then for the first time experienced some little 
difficulty in our respiration. The mules would halt every fifty 
yards, and after resting for a few seconds the poor willing 
animals started of their own accord again. The short breathing 
from the rarefied atmosphere is called by the Chilenos “ puna 
and they have most ridiculous notions concerning its origin. 
Some say “ All the waters here have puna : ” others that “ where 
there is snow there is puna ; —and this no doubt is true. The 
only sensation I experienced was a slight tightness across the 
head and chest, like that felt on leaving a warm room and 
running quickly in frosty weather. There was some imagina¬ 
tion even in this ; for upon finding fossil shells on the highest 
ridge, I entirely forgot the puna in my delight. Certainly the 
exertion of walking was extremely great, and the respiration 
became deep and laborious : I am told that in Potosi (about 
i 3,000 feet above the sea) strangers do not become thoroughly 
accustomed to the atmosphere for an entire year. The inhabit¬ 
ants all recommend onions for the puna ; as this vegetable has 
sometimes been given in Europe for pectoral complaints, it 
may possibly be of real service :—for my part I found nothing 
so good as the fossil shells ! 
When about half-way up we met a large party with seventy 
loaded mules. It was interesting to hear the wild cries of the 
muleteers, and to watch the long descending string of the 
animals ; they appeared so diminutive, there being nothing but 
the bleak mountains with which they could be compared. 
When near the summit, the wind, as generally happens, was 
impetuous and extremely cold. On each side of the ridge we 
had to pass over broad bands of perpetual snow, which were 
now soon to be covered by a fresh layer. When we reached 
the crest and looked backwards, a glorious view was presented. 
The atmosphere resplendently clear ; the sky an intense blue ; 
the profound valleys ; the wild broken forms ; the heaps of 
ruins, piled up during the lapse of ages ; the bright-coloured 
rocks, contrasted with the quiet mountains of snow ; all these 
together produced a scene no one could have imagined. 
Neither plant nor bird, excepting a few condors wheeling 
around the higher pinnacles, distracted my attention from the 
inanimate mass. I felt glad that I was alone ; it was like 
