The temperatures at 1.25 P.M. and 2.12 P.M. respectively were as
follows:--In the sun, between 3 and 4 feet above the snow, 72 deg..1 and
70 deg..5; in the shade, outside the cave, 36 deg..7 and 35 deg..8; at the
Observatory of Geneva, in the shade, 27 deg..3 and 28 deg..2, having risen from
24 deg..5 since noon. In the cave, 1 foot above the surface of the
ice-floor, the thermometer stood at 24 deg..8; and in a hole in the ice,
some few inches below the surface, 24 deg..1. In the large fissure, which has
been already mentioned as the source of the summer currents of air, the
temperature at various points was from 29 deg..3 to 27 deg..5. The circumstances
of these currents of air were now of course changed. Instead of a steady
current passing from the fissure into the cave, and so out by the main
entrance into the open air, strong enough to incline the flame of a
candle 45 deg., M. Thury found a gentle current passing from the cave into
the fissure, sufficient only to incline the flame 10 deg., and near the
entrance 8 deg., while in the entrance itself no current was perceptible at
4 P.
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