t favoured by a high rate of
velocity.

The special features of the fractures caused by the small-calibre
bullets were: (1) The nature of the exit wound, which in a certain
proportion of the cases exhibited the so-called 'explosive' character.
(2) The presence, in a marked degree in the severe cases, of the
condition spoken of in Chapter III. as 'local shock.' (3) The striking
contrast of clean perforation and extreme comminution in different
cases. (4) The occasional occurrence of fractures of a very high degree
of longitudinal obliquity. (5) The rarity of any that could be termed
transverse fractures. (6) The general tendency of longitudinal fissuring
when it occurred to stop short of the articular extremities of the
bones.

It will perhaps be most convenient to consider first the explanation of
the development of the so-called explosive apertures, and then to pass
on to a general consideration of the types of fracture commonly met
with, before proceeding to the description of the injuries to the
separate bones.

_Explosive wounds in connection with fractures._--The aperture of entry
in these injuries presented little or no deviation from the normal,
unless it was due to the passage of ricochet bullets, when it might be
very irregular, but usually not of great size.

[Illustration: FIG. 47--(21) 'Explosive' Exit Wound of Forearm over
margin of ulna. Note creased tongue of skin originally covering whole
wound. The entry wound was a small typical circular one]

The aperture of exit offered special features beyond simple increase in
size. First of all, as in the small type wounds, the actual extent of
destruction of the skin was small, this having been projected outwards
by the passing bullet and then either burst or torn by the bullet and
accompanying bony fragments. Fig. 47 well illustrates this feature. A
triangular tongue of skin was lifted by the passing bullet and probably
by the lower end of the upper fragment of the fractured ulna; through
the resulting opening a mass of soft tissues and bone fragments, bound
together by an infiltration of coagulated blood, was extruded,
separating the lateral lips of the aperture, while the original tongue
has shortened and retracted up to the top of the wound.

The small extent of skin actually destroyed is an important element in
the rapid contraction often seen in these wounds when they progress
favourably. Thus the large wound portrayed in fig. 48 contracted to
one-f