'C 4 4*2 J 
fetting out the next morning, the former had got 
down to 109, and the latter to 12. 
80. In the two laft mentioned obfervations the hy- 
grometer had been expofed long enough to the' open 
air, to conform itfelf to the degree of humor preva- 
lent in the place ; but we had not time for the ob- 
fervations I was mod: defirous to make with accu- 
racy. The hygrometer being ufually fhut up in the 
box of my barometer, it would have been neceffary 
to have left that open fome time;, in Order that it 
fhould adapt itfelf to the date of the air, and we 
could alloyy.but a very fhort time fot thefe obfer- 
vations. 
81. The firft of them was made at nine in the 
morning, at the height of about 1000 toifes above 
the plain. The Iky appeared clear over head, but 
the plain was darkened with vapours. The ther- 
mometer in the fun flood at 13I, and the hygrome- 
ter rofe to 1 1 5 in the ihade. 
82. It was two in the afternoon when we reached 
the top of the mountain, which is always covered 
with an enormous mafs of ice and fnow. We found 
there a very ftrong fouth wind, which is the warmed 
wind in our plains : befides this, we were nearly at 
the hotted time of the day : and yet the thermometer, 
upon being expofed to the fun, fhewed only 6. The 
wind, and the coldnefs of this region, obliged us to 
quit the fummit in a quarter of an hour, during 
which the hygrometer had rifen only to 119 ; but 
we judged that it was not yet dationary. 
83. In this fhort time we experienced a nevy effed 
of the diminifhed humidity of the air, which fur- 
prized us all three v.ery much. We foand our fkin 
withered 
