rying interval after death, usually within twelve hours, there is a
general contraction and hardening of the muscles due to chemical
changes, probably of the nature of coagulation, in them. This begins
in the muscles of the head, extends to the extremities, and usually
disappears in twenty-four hours. It is always most intense and most
rapid in its onset when death is preceded by active muscular exertion.
There have been cases of instantaneous death in battle where the body
has remained in the position it held at the moment of death, this
being due to the instantaneous onset of muscular rigidity. The blood
remains fluid for a time after death and settles in the more dependent
parts of the body, producing bluish red mottled discolorations. Later
the blood coagulates in the vessels. The body loses moisture by
evaporation. Drying of the surface takes place where the epidermis is
thin, as over the transparent part of the eye and over areas deprived
of epidermis. Decomposition and putrefaction of the body due to
bacterial action takes place. The bacteria ever present in the
alimentary canal make their way from this into the dead tissue.
Certain of these bacteria produce gas which accumulates in the tissues
and the body often swells enormously. A greenish discoloration
appears, which is due to the union of the products of decomposition
with the iron in the blood; this is more prominent over the abdomen
and appears in lines along the course of the veins. The rapidity with
which decomposition takes place varies, and is dependent upon many
factors, such as the surrounding temperature, the nutrition of the
body at the time of death, the cause of death. It is usually not
difficult to recognize that a body is dead. In certain cases, however,
the heart's action may be so feeble that no pulse is felt at the
wrist, and the current of the expired air may not move a feather held
to the nostril or cloud the surface of a mirror by the precipitation
of moisture upon it. This condition, combined with unconsciousness and
paralysis of all the voluntary muscles, may very closely simulate
death. The only absolute evidence of death is given by such changes as
loss of body heat, rigor mortis or stiffening of the muscles,
coagulation of the blood and decomposition.

CHAPTER III

THE GROWTH OF THE BODY.--GROWTH MORE RAPID IN EMBRYONIC PERIOD.--THE
COOeRDINATION AND REGULATION OF GROWTH.--TUMORS.--THE GROWTH OF TUMORS
COMPARED WITH NORMAL GR