trajectory the range is short. The gun in the fortress does not lob
its shell, but throws it. The course of the gun shell is much more
straight. It therefore can only hit the howitzer and its crew
indirectly by exploding its shell just above them. Until recently, the
gun was master of the howitzer for three reasons:--

First, because the largest howitzers capable of movement and of being
brought up against any fortress and shifted from one place of
concealment to another were so small that their range was
insignificant. Therefore the circumference on which they could be used
was also a small one; their opportunities for hiding were consequently
reduced; the chances of their emplacement being immediately spotted
from the fortress were correspondingly high, and the big gun in the
fortress was pretty certain to overwhelm the majority of them at
least. It is evident that the circumference αβγ offers far more
chances of hiding than the circumference ABC, but a still more
powerful factor in favour of the new big howitzer is the practical one
that at very great ranges in our climate the chances of spotting a
particular place are extremely small. Secondly, because the explosives
used, even when they landed and during the short time that the
howitzer remained undiscovered and unheard, were not sufficiently
powerful nor, with the small howitzers then in existence, sufficiently
large in amount in each shell to destroy permanent fortification.
Thirdly, because the effect of the aim is always doubtful. You are
firing at something well above yourself, and you could not tell very
exactly where your howitzer shell had fallen.

[Illustration: Sketch 20.]

What has modified all this in the last few years is--