ACROSS UNKNOWN SOUTH AMERICA 
the rim of the then cylindrical crater. The mountain 
behind those rocks was formed by high accumulations of 
red volcanic sand, which in time, by the action of rain and 
sun, had gradually consolidated into soft rock. 
The plateau extending northward, which was disclosed 
in all its entirety before me from the elevation of 1,600 
feet which we had reached, also seemed to possess an 
extinct crater shaped like a crescent with steep slopes and 
two rounded promontories on its side. 
The sky that day was partly covered by transparent 
feathery clouds and by dense mist near the horizon line 
to the east, but was quite clear to the west. As usual, that 
evening we were again treated to fairly handsome white 
lines radiating from the sun half way up the sky vault, 
but this time they were flimsy and not to be compared to 
the magnificent displays we had observed before. 
Our animals still sank in ochre-coloured sand, or 
stumbled on conglomerate rocks of spattered lava pellets 
embedded in sandstone. Capping the higher undulations 
we again found deposits of ashes. 
We travelled for long distances on a ridge at an 
elevation of 1,650 feet over a thick layer of sand and 
ashes mixed. Then campos spread before us, and upon 
them, here and there, grew stunted vegetation, the trees 
seldom reaching a greater height than fifteen feet. 
From our last high point of vantage, the crater with 
fantastic rocks and its continuation we had observed 
appeared to form a great basin. A subsidiary vent was 
also noticeable. Farther on our march we found other 
immense deposits of grey ashes and sand alternately — 
one great stretch particularly, at an elevation of 1,600 
feet. Water at that spot filtered through from under¬ 
neath and rendered the slope a grassy meadow of the most 
refreshing green. We were rising all the time, first going 
northwest, then due north. At noon we had reached the 
highest point. 
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