ACROSS UNKNOWN SOUTH AMERICA 
deep blue shadows cast by the spurs which projected, some 
to the southeast, others due south — that is, it will be 
understood, on the southern face of the range. 
Thick deposits of cinders lay in the valley. On 
approaching an intermediate and lower range we cut our 
way through scrub, chiefly of sciadera trees, seldom grow¬ 
ing to a greater height than seven feet. The domed hills 
showed through the grass great blocks of volcanic rock, 
while at the foot of the hills could be noticed huge boulders 
of consolidated ashes with veins of crystals and marble. 
There, too, the stratification was vertical. There was 
lamination in some of the rock, but not in the granite 
blocks nor in the blocks of marble, which appeared to have 
been subjected to enormous heat. Some of the rock had 
been in a state of absolute ebullition. 
At the spot where we crossed the range, starting our 
ascent from an elevation of 1,100 feet, were immense holes, 
vents, and cracks in the earth’s crust. As we rose slightly 
higher among many chains of low hills, we were upon a 
horizontal stratum of laminated granite. Higher still we 
passed a semicircular hill composed of immense blocks of 
granite. In the centre of the semicircle was a great round 
hole, thirty feet in diameter, an extinct crater. Farther on, 
ascending upon an inclined plane, we came to another 
similar semicircle, not of rock that time, but of red earth 
and cinders. When we reached the highest point (ele¬ 
vation 1,270 feet) of the divide, we had to our left huge 
pinnacles and pillars of rock of the most fantastic shapes, 
monoliths from ten to fifteen feet high, and rocks hollowed 
by the action of fire. Big boulders, which had become per¬ 
fectly rounded by having been shot through the air and 
revolved at a great speed while in a half-solid condition, 
were to be seen scattered all over the inclined planes of 
the saddle of the divide. Giant cacti grew in abundance 
in the interstices between rocks. Although most of the 
rocks were blackened outside, by chipping off the outer 
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