The achievements of our troops from September 25 to October 3, 1915, in this region may be thus summarised: They scaled the whole of the glacis of l'Epine de Vedegrange; they occupied the ridge of the hollow at Souain; debouched in the opening to the north of Perthes to the slopes of Hill 195 and as far as the Butte de Tahure; carried the western bastions of the curtain of le Mesnil; advanced as far as Maisons de Champagne and took by assault the "hand" of Massiges. That is to say that they captured an area about forty 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.