990 
THROUGH ASIA 
on, so that it reached its maximum in the evening. But 
during the night it sank again, and became edged with 
a thin fringe of ice. 
The cold made itself felt immediately the sun set, the 
thermometer falliiip' to five or six dep-rees above freezing- 
point. But it was the everlasting wind that was so tiring, 
and that made the tent cold, because it did not subside 
until after darkness set in. The nights were always calm 
and bright. Owing to the active radiation, the uppermost 
layer of the earth invariably froze ; but just as invariably 
it thaw'ed again immediately the sun rose in the morning. 
That night the minimum temperature was i2°2 Fahr. 
{-11° C.). The altitude above sea-level was 16,675 foet. 
