t
is therefore only what might be reasonably expected when we remember
that every such bullet track is lined by a thin layer of damaged tissue.

[Illustration: FIG. 25 (_b_).--Great Omentum carried by the bullet into
an exit track leading from the abdominal cavity. A. Outline of opening
in the peritoneum]

When fully healed, the points of entry and exit are so insignificant as
to be less obvious than ordinary acne scars, and later are often hardly
visible, but for a considerable period they are often more palpable than
apparent. This depends upon the induration of the line of cicatrix
corresponding to the course of the original track which is adherent to
the two points. The induration is indeed so marked as to occasionally
give rise to the suspicion that a foreign body such as a fragment of
lead or of the mantle of the bullet has been enclosed during the healing
of the wound.

In the deeper portions of the tracks the extreme density of the cicatrix
is a factor of great prognostic importance, since if it implicates
muscles, tendons, vessels, or nerves, impairment of movement,
circulatory disturbance, or signs of neuritis or nerve pressure are
often witnessed. Thus, for instance, a track traversing the calf, will
more or less tie the whole thickness of the structures perforated at one
spot, and the apertures of entry and exit may be visibly retracted when
the muscles are put in action with consequent pain and stiffness to the
patient. Such pain and stiffness form some of the most troublesome
after-consequences of many simple wounds. It is remarkable for how long
a period after the healing of the wound and resumption of active duty
the patients suffer from pain in and radiating from the locality of the
wound, when fatigued or suffering from stiffness from the prolonged
retention of one attitude or exposure to cold. The cords, however,
eventually completely disappear, and the cicatrices become moveable. The
effects of secondary pressure on the vessels and nerves are considered
under the headings devoted to those structures.

_Suppuration._--While the occurrence of deep suppuration or septic
phlegmon was rare, local suppuration of the apertures of entry and exit
was seen in a considerable proportion of the wounds. This was referable
to infection from the skin itself, or to infection from without
subsequent to the infliction of the injury. Infection from the skin,
difficult to obviate at all times, is especially likely to