ACROSS UNKNOWN SOUTH AMERICA 
south in the inner part of the crater. The northern face 
of this vertical wall showed thick strata cracked into 
squares and rectangles with a dip in two different direc¬ 
tions at an angle. There a draining channel had formed. 
Two rows of circular holes, like port-holes, were to be 
seen, one directly under the summit, the other one third 
down the cliff side. A giant, rectangular tower of solid 
rock stood erect, parallel to the great wall. Skirting this 
vertical wall, we travelled northwest-by-west, rising grad¬ 
ually to 1,800 feet on a deep layer of red, volcanic sand 
and grey ashes. 
Looking back to the east, we had a complete view of 
the two-tiered plateaux with their vertical, northern walls, 
showing a dip south in their stratification. A crowning 
mound could also be observed surpassing their height, 
when we rose still higher to 1,900 feet on the summit of 
a ledge of cracked lava, with a slant westwards. On the 
eastern side, where it had crumbled owing to a subsidence, 
it showed a rounded moulding, whereas on the other side 
were great waves of lava. The lava had flowed from east 
to west. 
After leaving this curious spot, we went over undu¬ 
lating red and ochre-coloured sand and more grey ashes. 
We rose twice to an elevation of 2,000 feet. We crossed a 
streamlet of delicious water flowing north over a red lava 
bed. Then more and more ashes were found all along. 
A second stream, also flowing north, was then negotiated, 
also over a red lava bed (elevation 1,800 feet), after which 
we climbed to 2,000 feet, descending soon after to 1,900 
feet on the banks of another river flowing northeast. 
At this spot were two more enormous lava-flows — one 
on each side of the stream, and extending in a tortuous 
course from southwest and northeast. The lava had 
flowed northeast. 
On rising slowly in deep red sand to an elevation of 
2,100 feet, we saw two prominent elevations of brilliant 
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