Its Method of Action.
The most important question concerning the penetration of the enemy’s line is perhaps the action of the reinforcements (renforts), and as that action has always fallen short, we have never been able to attain the victory which has seemed so nearly within our reach.
The inertia of the second line and its expenditure without effect arise from two causes.
To take the first trenches is a task relatively easy; the artillery preparation is minutely regulated; the terrain is well known, and the attack is therefore free and open and is pushed through without reservation. But when the first lines have been crossed, one enters thenceforth into the domain of the unknown, one is on the lookout for ambushes and apprehends an unexpected trap at each step; this disquietude slows up the march and quickly transforms into a surprise the least activity of the enemy. A resistance which starts up suddenly intimidates and paralyses the second line immediately, because the fear of the enemy leads to exaggeration of his strength and the mental disturbance prevents locating and estimating him rapidly. In addition, the reinforcements have during long hours of waiting been subjected to a very demoralizing artillery fire.
All these causes so influence the second line that when it goes into action, it attacks without spirit and soon stops.
The second cause arises, as I have previously mentioned, from a faulty conception of the action of the second line.
In place of having a second line of attack analogous to the first, coming into the fight in one body and marching straight on to the assigned objectives, the superior commander uses these troops as reinforcements, which he throws in at the point where he judges their employment necessary. Now it is impossible for this commander to see clearly in the mêlée, he must wait a long time for the situation to unravel, and as it is necessary for him to be properly informed to send in his reinforcements opportunely, they always arrive too late. Having generally received orders which are ill defined and not having been able to prepare beforehand for the rôle that falls to them, their attitude is necessarily weak and hesitating.[[10]]
It is absolutely necessary to keep pushing on in a brutal, preconceived, and almost unintelligent manner until the last link is broken, otherwise hostile reinforcements will suddenly arrive and shatter the supreme effort.
Choice of Troops for the Second Line.—This line being subject to the severe trial of bombardment and of the rifle fire directed on the first line sweeping the ground behind, and being obliged to act with as much decision as the troops of the first line, it should be particularly well officered and be composed of troops of excellent spirit; now it often happens that less reliable troops are placed in this line, and far from pushing the first line forward, they stop short of it.
Location of the Troops of the Second Line. The Moment for Putting Them in Action.—During the preparation, the troops of the second line await their turn in the shelters which open into the approach boyaux. It would be very advantageous if they could be placed as close as possible to the parallel of departure[[11]] in order to profit from the more or less complete protection against hostile artillery fire which comes from being close to the hostile trenches; but in general this will not be possible, except where the German and French trenches are separated by a considerable distance; in this case, there will be enough space between the parallel of departure and the old trench to install several support trenches.