orty square kilometres in extent. The
importance of that figure is shown when one examines on the map
accompanying this report the position of the German trenches, with a
view to understanding the system of defence adopted by our adversaries.
Two positions, distant from three to four kilometres from each other,
stand out clearly. The first is the more dense; the trenches with their
alleys of communication present at certain points the appearance of a
wirework chessboard. Everywhere, to a depth of from 300 to 400 metres
there are at least three parallel lines, sometimes five. The trenches
are separated from each other as a rule by wire entanglements varying in
width from 15 to 60 metres.

[Sidenote: The second position.]

[Sidenote: Alleys of communication.]

The second position comprises only one trench, reinforced at certain
points by a supporting trench. It is everywhere constructed, as is the
wire network in front of it, in the form of a slope. On top there are
merely observation stations with machine-gun shelters connected with the
trench by an alley of communication. Between the two positions the
terrain was also specially prepared, being cut up by transverse or
diagonal trenches. The alleys of communication constructed to facilitate
the firing, which were in many cases protected by wirework, make
possible, according to the German method, a splitting up of the terrain
by lateral fire and the maintenance, even after the tide of the
assailants had flooded the trenches, of centres of resistance, veritable
strongholds that could only be reduced after a siege. The positions of
the artillery were established, as were also the camps and provision
depots, behind the first position, the principal line of defence.

[Sidenote: German organization known.]

The whole German organization was known to us. It was shown on our maps,
and every defensive work, trench, alley of communication, and clump of
trees was given a special name or a number preceded by a certain letter,
according to the sector of attack wherein it was situated. This minute
precision in the details of the preparation is worthy of being pointed
out; it constitutes one of the peculiarities of the present war, a
veritable siege war, in which the objective has to be realised
beforehand and clearly determined, every piece of ground having to be
captured by heavy fighting, as was formerly every redan and every
curtain.

The bombardment of the German positions b