ACROSS UNKNOWN SOUTH AMERICA 
a minimum of 60° and a maximum temperature 
of 75°. 
Owing to the usual trouble of recovering the mules in 
the morning, we only left camp at 10.30 a.m., rising over 
great masses of ferruginous rock, which showed through 
the deposits of ashes and sand at an elevation of 1,950 
feet. The immense view of the campos in great un¬ 
dulations was really exquisite to the west and south¬ 
west. 
My mules were then travelling over a strange, narrow 
strip of rock at a height of 2,050 feet — in some places 
only a few yards across — on the top of vertical walls 
dividing two deep valleys, one to the south, very extensive, 
with great lava-flows; another to the north. In the latter 
valley an immense, extinct crater was visible, in three 
well-defined, internal terraces and a deep, central 
depression. 
Upon climbing on the summit of a high, conical hill, 
I further discovered that the crater had an elongated 
shape, the longest diameter being from north to south, 
the southern and lower part being overlapped by a 
voluminous flow of lava, which also covered a great part 
of the mountain slope. Strange monoliths were numer¬ 
ous, among the many fantastically shaped rocks, and also 
boulders lying about at all angles. One, like a huge table, 
rested on the top of another, upon which it had fallen with 
great force, as could be seen by the vertical splitting of 
the rock underneath. The rock above appeared simply 
broiled, and so were the huge masses of debris, especially 
of ferruginous rock, which had evidently been ejected 
by that crater. The entire summit of the crater cone 
(2,100 feet above sea level) was of hard black baked rock. 
Close by, to the north, was another peculiar oval 
depression, the highest part of which to the northwest 
was in four distinct terraces in the interior. The eastern 
part was more flattened, not unlike a huge soup plate. In 
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