tance of a flat trajectory is progressively lost, however, with
any rifle, as the weapon is gradually sighted to greater distances. Thus
when sighted to 2,000 yards the bullet from the Lee-Metford rifle rises
174 feet, and a whole army might comfortably be situated over a
considerable area within that distance. The importance of flatness of
trajectory is also influenced by the nature of the ground occupied by
the combatants. Thus when the area to be covered consists in ground
first rising then falling from the rifleman, the trajectory will become
more or less parallel to the surface crossed, and the 'dangerous zone'
will be correspondingly increased in extent. On the other hand, when the
ground slopes away from the rifleman the rise of the projectile is
exaggerated, and reaches its most limited capacity of covering an
intervening space when the flight crosses a hollow.
_Revolution of the bullet._--It only remains in this place to say a few
words concerning the revolution imparted to the bullet by the rifling of
the barrel. This ensures the flight of the projectile on a line parallel
to its long axis, and notably increases its power of penetration.
Both these properties of the flight are to the advantage of the wounded,
since, as already mentioned, the more exactly the impact corresponds to
a right angle with the skin, the more limited will be the area of
contusion, even if it be of the most severe character, while to the
twist of the bullet must be ascribed a not inconsiderable part in the
explanation of the ready and neat perforations of narrow structures
which are frequently produced.
It has been pointed out that the Lee-Metford bullet turns on its own
axis once in a distance of ten inches, while the Mauser revolves once in
a distance of eight and eleven-sixteenths inches; hence not more than at
most two revolutions are made in tracks crossing the trunk, and not more
than half a full revolution in the perforation of a limb. None the
less, no one can deny the influence of the one half turn of supination
in entering a perforating tool of any description, both as preventing
splintering, and in preserving the surrounding parts from damage.
Beyond this, the spiral turn of the bullet, by diverting a part of the
transmitted vibrations into a second direction, must, in the case of
wounds of the body, help to throw off contiguous structures, and while
those that are in actual contact are more severely contused, the
surr
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