where it struck the
bodies of the second and third dorsal vertebrae, one third of
the bodies of each of which were driven into an extensive
laceration of the lung; it then grooved the inner surfaces of
the eighth and ninth ribs, fractured the tenth and eleventh,
and passing the twelfth traversed the deep muscles of the back
to the pelvis. Beyond the injury to the occipital lobe, the
cerebellum was found to be lacerated and extensively bruised
and ecchymosed.

_Complications._--_Hernia cerebri_ as a primary feature has already been
mentioned as one of the peculiarities of some explosive wounds. In the
later stages of the cases in which primary union did not take place the
development of granulation tumours was often seen, sometimes in
connection with slight local suppuration, sometimes over a cerebral
abscess. In some cases a wound which had once closed reopened and a
hernia developed. This sequence was chiefly of prognostic significance
as an indication of intra-cranial inflammation, usually of a chronic
character, and affecting rather the lowly organised granulation tissue
formed in the cavity than the brain itself. When primary union of the
skin flap and wound failed, the process of definitive closure of the
subjacent cavity was always a very prolonged one, and it was in such
cases that a great proportion of the so-called herniae developed.

_Abscess of the brain._--Local abscesses formed in a considerable
proportion of the cases where serious damage to the brain had occurred,
in whatever region this happened to be. I never saw one develop in cases
where primary union had taken place, even when bone fragments had not
been removed; neither did I ever see an abscess situated at a distance
from the original injury. I take it that the latter is to be explained
by the early date of the suppuration, and the fact that in the great
majority of small-calibre wounds the exit opening exists in the
situation of the contre-coup damages of civil practice.

The main feature in the symptoms when abscesses developed was the
insidious mode of their appearance, usually at the end of fourteen to
twenty-one days, and their comparative mildness.

Very slight evidences of compression were observed; thus, varying
degrees of headache, drowsiness, irritability of temper or depression,
twitchings, or in some cases Jacksonian seizures, combined with slow
pulse and slight rises of temperature. I never