ACROSS UNKNOWN SOUTH AMERICA 
we began to get thick cold mist, and it was about that time 
that the minimum temperature was usually registered 
— 58° Fahrenheit that particular night, May nineteenth. 
We were at quite a low elevation, merely 1,100 feet. 
When we started in the morning, we found more sand 
and volcanic debris over ridges some 100 feet or so above 
the level of the river. A torrent, 15 metres wide, flowing 
swiftly west-southwest on a red lava bed, was crossed, 
the mules slipping terribly on the polished rock. More 
ashes and sand were found as we ascended to an elevation 
of 1,200 feet, from which height we discerned a much- 
terraced headland to the east and two streams meeting 
and flowing south where we eventually crossed them. One 
of those watercourses descended in cascades over lami¬ 
nated successive flows of lava, between which thin layers 
of white crystallization could be seen. 
Slightly higher, at 1,250 feet, we sank again in yellow 
and grey ashes. 
Across campos we reached another foaming torrent, 
flowing as usual over a lava bed, but this time in a 
northwesterly instead of in a southerly direction. That 
day we met with many watercourses. Having risen to 
1,450 feet, we soon after found another streamlet (ele¬ 
vation 1,280 feet). Again a red lava-flow was exposed 
in its bed and showed heavy upper deposits of grey ashes, 
with above them a thick layer of yellow-ochre sand 
(1,300 feet). 
The distances on the journey were measured by a 
watch, the speed of the animals at the time being naturally 
taken into consideration. It was not possible to use the 
usual bicycle wheel with a meter attached, which is used 
with so much success in the Arctic regions or in countries 
where travelling more or less in a straight line and on a 
level surface is possible. 
Another limpid stream flowing southwest (elevation 
1,200 feet) was reached, then more deep sand and ashes. 
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