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setting out the next morning, the former had got down to 109, and the latter to 12.

80. In the two last mentioned observations the hygrometer had been exposed long enough to the open air, to conform itself to the degree of humor prevalent in the place; but we had not time for the observations I was most delirious to make with accuracy. The hygrometer being usually shut up in the box of my barometer, it would have been necessary to have left that open some time, in order that it should adapt itself to the state of the air, and we could allow but a very short time for these observations.

81. The first of them was made at nine in the morning, at the height of about 1000 toises above the plain. T he sky appeared clear over head, but the plain was darkened with vapours. The thermometer in the fun stood at 13 3/4,, and the hygrometer rose to 115 in the shade.

82. It was two in the afternoon when we reached the top of the mountain, which is always covered with an enormous mass of ice and snow. We found there a very strong south wind, which is the warmest wind in our plains : besides this, we were nearly at the hottest time of the day: and yet the thermometer, upon being exposed to the sun, shewed only 6. The wind, and the coldness of this region, obliged us to quit the summit in a quarter of an hour, during which the hygrometer had risen only to 119 ; but we judged that it was not yet stationary.

83. In this short time we experienced a new effect of the diminished humidity of the air, which surprized all three very much. We found our skin

catchword withered /catchword