The process is compound, and into it there enter three elements. In
the first place, the body is robbed rapidly of its waste force, and
the reserve and active elements of force are, consequently, called
upon to the depression of the organism altogether. This obtains
because the medium surrounding the body, the air, unless it be
artificially heated, removes from its contact with the body a larger
proportion of heat than can be spared; and it might be possible to
produce such an influence on the body by sudden extraction of its heat
as to destroy it at once by the mere act. If a man could be surrounded
with frozen mercury he would die instantaneously, as from shock, by
the immediate extraction of his heat. But in ordinary cases, and under
ordinary circumstances, the mere rapid extraction of waste heat is not
sufficient to account for all the mischief produced by a low
temperature; for by artificial warmth and non-conducting garments, we
counteract the influence, and that, too, in a manner which proves
pretty successful. We may, therefore, leave this element of extraction
of heat as a most important, but not as the sole, agent of evil.