Thus a bullet entered below the
centre of the right clavicle and emerged 2-1/2 inches below, above the
angle of the scapula, at its axillary margin. The arm was outstretched
at the moment of the reception of the injury; but when the wound was
viewed with the limb placed alongside the trunk, it seemed almost
impossible that the chest cavity could have escaped. In some cases of
this kind the difficulty was at once cleared up by noting evidence of
injury to the axillary nerves.

A word will suffice as to the treatment of these wounds. The only
special indication was to keep the scapula at rest for a sufficient
period. I have dealt with the anatomy of them at such length only
because in their extreme form they are so highly characteristic of the
nature of the injuries which may be produced by bullets of small
calibre.

_Penetrating wounds of the chest._--Tracks crossing the thoracic cavity
in every direction were common. When the erect attitude was maintained,
frontal and sagittal wounds, pure or oblique, were received; when the
prone position was assumed, longitudinal tracks, either purely or
obliquely vertical, were the rule. Experience of wounds of the latter
class was extensive in the present campaign, from the fact that so many
of the advances were made in prone or crawling attitudes. The vertical
and transverse tracks each possessed the special characteristic of
frequently implicating both the thoracic and abdominal cavities, but the
vertical were often prolonged into the neck, or even downwards through
the pelvis. The vertical wounds in addition sometimes exhibited one very
important feature, the fracture of several ribs from within, often at a
very considerable distance from the aperture of either entry or exit.

[Illustration: FIG. 81.--Superficial Track in anterior Wall of Trunk]

_Characters of the apertures of entry and exit._--As has already been
mentioned, the chest-wall was one of the situations in which the
aperture of entry was often large, and the oval form due to obliquity of
impact on the part of the bullet was particularly well marked. The exit
wounds were often smaller than those of entry, especially if the bullet
emerged by an intercostal space; even when the ribs were comminuted, the
fragments were, as a rule, too small to occasion more than a slightly
enlarged and irregular aperture. Taken as a class, however, and putting
aside explosive exit wounds, wounds of the chest afforded more numerous
ex