It now became rather a painful experiment to touch any metallic
substance in the open air with the naked hand; the feeling
produced by it exactly resembling that occasioned by the opposite
extreme of intense heat, and taking off the skin from the part
affected. We found it necessary, therefore, to use great caution
in handling our sextants and other instruments, particularly the
eye-pieces of telescopes, which, if suffered to touch the face,
occasioned an intense burning pain; but this was easily remedied
by covering them over with soft leather. Another effect, with
regard to the use of instruments, began to appear about this time.
Whenever any instrument which had been some time exposed to the
atmosphere, so as to be cooled down to the same temperature, was
suddenly brought below into the cabins, the vapour was instantly
condensed all around it, so as to give the instrument the
appearance of smoking, and the glasses were covered almost
instantly with a thin coating of ice, the removal of which
required great caution, to prevent the risk of injuring them,
until it had gradually thawed, as they acquired the temperature of
the cabin. When a candle was placed in a certain direction from
the instrument with respect to the observer, a number of very
minute _spiculae_ of snow were also seen sparkling around the
instrument, at the distance of two or three inches from it,
occasioned, as we supposed, by the cold atmosphere produced by the
low temperature of the instrument almost instantaneously
congealing into that form the vapour which floated in its
immediate neighbourhood.
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