diminished pressure of the atmosphere, at a lower temperature than it
does in a less lofty country; the case being the converse of that of a
Papin's digester. Hence the potatoes, after remaining for some hours
in the boiling water, were nearly as hard as ever. The pot was left on
the fire all night, and next morning it was boiled again, but yet the
potatoes were not cooked. I found out this, by overhearing 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 mountains
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, similar 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,
[4] 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 sticking 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 enveloped 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 limit of
vegetation, and found good quarters for the night under the shelter of
some large fragments of rock. We met here some passengers, who made
anxious inquiries about the state of the road. Shortly after it was
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