3. It causes contraction of the capillaries, and thus lessens the
superficial circulation, and stops the cutaneous secretion.
4. It probably destroys the principle of vitality, equally in every
part, and does not exclusively disturb the functions of any particular
organ.
These positions have been confirmed by experiment. Dr. _Chassat_ states
that in an animal immersed in a cold bath, death may take place at 79°
Fahr. (26 _Centig._), although it may be sometimes cooled down as low as
69° (17 _Cent._) before it dies; but, _cæteris paribus_, the animal dies
sooner as the cooling is more rapid.
M. _Portal_ thinks that cold produces death by inducing apoplexy, and
remarks that the examination of the bodies of persons who have died from
cold, proves the presence of sanguineous congestions in the vessels and
cavities of the body, and especially in those of the brain. Dr. _Cooke_,
however, has remarked that “M. _Portal’s_ notions on this subject seem
to want confirmation. Excessive cold undoubtedly produces, first
drowsiness and afterwards a profound sleep, in which the unfortunate
individual generally perishes; but we have not on record a sufficient
number of cases with particular descriptions of symptoms and appearances
on dissection, to enable us to say positively that cold kills by
apoplexy.”
After death the blood is generally florid in the aorta, so that the
animal does not die of suffocation; the heart sometimes contracts feebly
after the muscular irritability of the limbs and intestines are nearly
destroyed; the cerebral veins contain but little blood; the ventricles
contain a small portion of fluid. Mr. _Brodie’s_ experiments coincide in
most respects with those of Dr. _Chassat_, who uniformly found after
death, the heart much distended with blood, as in Syncope, scarlet blood
occupying the left side; and he also found that the heart ceased to
contract before the diaphragm, so that he has seen the animal
insensible, and gasp for breath, even after the chest was opened and the
heart excised! The muscles were unusually florid, and the peristaltic
motions of the intestines were generally observed to continue longer
than the action of the heart. The voluntary muscles, he says, lose their
irritability in different degrees, those of the legs before those of the
thighs, and those of the thighs before the abdominal muscles.