d's test); (c) looking through the web of the fingers at
a bright light (diaphanous test); (d) the dulling of a steel needle when
thrust into the living body; (e) the clear outline of the dead heart
when viewed in the fluorescent screen. (3) The state of the eye; the
tension is at once lost; iris insensible to light, fundus yellow in
colour; cornea dull and sunken. (4) The state of the skin; pale, livid,
with loss of elasticity. (5) Extinction of muscular irritability. The
above signs afford no means of determining how long life has been
extinct. The following, however, do:

=Cooling of the Body.=--The average internal temperature of the body is
from 98 deg. to 100 deg. F. The time taken in cooling is from fifteen to twenty
hours, but it may be modified by the kind of death, the age of the
person, the presence or absence of clothing on the body, the surrounding
temperature, and the stillness or otherwise of the air about the body.
Still, the body, other things being equal, may be said to be _quite
cold_ in about _twelve hours_.

=Hypostasis= or =post-mortem staining= is due to the settling down of
the blood in the most dependent parts of the body while the body is
cooling. It is a sure sign of death, and occurs in all forms of death,
even in that due to haemorrhage, although not so marked in degree.
Post-mortem staining (_cadaveric lividity_) begins to appear in from
eight to twelve hours after death, and its position on the body will
help to determine the length of time the body has lain in the position
in which it was found. The staining is of a dull red or slaty blue
colour. It must be distinguished from ecchymosis the result of a bruise,
by making an incision into the part; in the case of hypostasis a few
small bloody points of divided arteries will be seen, in the case of
ecchymosis the subcutaneous tissues are infiltrated with blood-clot.
Internally, hypostasis must not be mistaken for congestion of the brain
or lungs, or the results of inflammation of the intestines. If the
intestine is pulled straight, inflammatory redness is continuous,
hypostasis is disconnected. About the neck hypostasis must not be
mistaken for the mark of a cord or other ligature. When the blood is of
a bright red colour after death (as happens in poisoning by CO or HCN,
or in death from cold), the hypostasis is bright red also.

=Cadaveric Rigidity--Rigor Mortis.=--For some time after death the
muscles continue to contract under stimuli.