less importance as affecting spent
bullets only, that bullets, which have perforated the body but lie
between the skin and the clothing, leave no sign of cauterising action
on either, may be mentioned. None the less, the sources of heating while
the bullet is passing from the barrel are many and obvious. Thus there
is the heat consequent on explosion of the powder, the warm state of the
barrel itself when the rifle has been fired a few times consecutively,
and the heat resulting from the force and friction essential to the
propulsion of the bullet through the barrel. Again, bullets covered with
wax before their introduction into the barrel retain no trace of this
when they have been fired, although at any rate the portion covering
the tip is not exposed to friction on the part of the rifle, and lastly
the base of the bullet has no other explicable reason for its
innocuousness than subjection to a certain degree of heat. While not
claiming any cauterising action on the tissues by the bullet, I should
therefore still be inclined to allow the probability of the heat to
which the surface of the bullet is exposed exerting a cleansing action
on the projectile. In regard to this point it is interesting to bear in
mind that shots from an ordinary gun seldom or never give rise to
infection.

Foreign bodies were rarely carried into the wounds with the bullet. I
saw several instances in which portions of the metal of cigarette cases
and of cartridge cases when the bullet had perforated cartridges in the
wounded man's bandolier, and in one instance small pieces of glass from
a pocket mirror, must have been carried in without any obvious ill
effect. Fragments of clothing, on the other hand, in every case caused
suppuration: clothing was not often carried in, the khaki linen was
perforated with a clean aperture, most commonly a slit; but the thick
woollen kilts of the Highlanders, and thick flannel shirts, occasionally
furnished fragments. The introduction of large pieces of clothing is a
sure proof of irregularity of impact on the part of the bullet. The
frequency with which portions of cloth were introduced from the kilt was
one of the strongest surgical objections to its retention as a part of
the uniform on active service.

Retained bullets themselves remained as foreign bodies in a certain
number of cases. I cannot say that suppuration never followed the
retention of a bullet, since in two of the instances where I saw such
rem