t in diving under the margin of a rib and turning longitudinally up
or down. Removal was sometimes necessary, either from the prominence
produced, the presence of pain, or the continuance of suppuration. Some
of the specimens removed offered interesting evidence of the capacity of
the ribs to withstand considerable violence from a bullet. These were
slightly bent, and marked by a half-spiral groove. I saw such bullets
removed from the thoracic and the abdominal wall, and the evidence
seemed rather against the groove having been produced prior to their
entrance into the body.

[Illustration: FIG. 82.--Spirally grooved Mauser Bullet]

_Wounds of the diaphragm._--Perforations of the diaphragm were very
frequent, and as a rule of small significance. When, however, the course
taken by the bullet was parallel with that of the slope of the
diaphragm, a more or less extensive slit was the result. I saw such a
wound still gaping, and 2 inches in length, in the body of a patient
who died three weeks after the infliction of a fatal abdominal injury.

In several other obliquely transverse thoracic wounds there was reason
to assume the existence of similar slits. Certain signs were more or
less constant under these circumstances. These consisted in shallow
respiration, often accompanied by a groan or the slightest degree of
hiccough on inspiration, and considerable increase in respiratory
frequency. In one patient the respirations were at first 48, only
dropping to 36 some seventy hours after the reception of the injury. In
some of the cases in which the abdominal cavity was implicated, wound to
the diaphragm seemed a more likely explanation of early, frequent, and
painful vomiting than did visceral injury. The possibility of the later
development of diaphragmatic herniae in some of these patients will have
to be borne in mind in the future.

_Visceral injuries._--The frequent escape of the thoracic viscera from
injury, putting aside the lungs which fill so great a part of the
cavity, was very remarkable. I never saw a case in which I could assume
injury to any of the posterior mediastinal viscera, although such may
have occurred on the field of battle. An injury to the oesophagus, for
instance, would almost of necessity be accompanied by wound of either
one of the large vessels, even the thoracic aorta, or the spinal column.
I was somewhat surprised, however, to learn on enquiry from surgeons who
had seen a large number of the d