In the artillery depots, very numerous gun crews should be organized beforehand for the torpedo guns, and not date only from the day before and be at their first try out, as at Arras.
The aerial torpedo, terrorizing the defenders in the interior of their shelters, already neutralizes them in part; but the best plan of eliminating the enemy is to destroy him. In order to destroy him, it is necessary to force him to expose himself, to oblige him to come out to become the prey of the iron hail. For this there are several means:
Have the infantry advance during the preparation by the artillery;
Simulate the attack;
Finally a third method that can be transferred from the domain of fox hunting to that of the war with Germany: smoke him out.
The first plan is not applicable from first trenches as they are too near the enemy; we shall speak of this again.
In order to simulate an attack, interrupt the artillery fire suddenly and open rifle fire with a great deal of shouting; the enemy hurries out immediately to his combat positions; after several minutes’ waiting, a violent rafale of 75. This is what we did from time to time when we wished to make the Germans come out into their trenches so that we could demolish some of them by artillery fire. At Arras, there was a brusque interruption of artillery fire for ten minutes, but it was an absolute and impressive silence. The Germans were not misled by it, and when the interruption for the real attack came with its fusillade and noise, they manned their trenches to meet it.
As a third scheme we have suffocating grenades and cartridges, which irritate the eyes and produce tears and render the neighborhood of the spot where they fall untenable for several minutes. We could also have projectiles of larger dimensions, containing materials giving off heavy, suffocating gas. Thus this gas would creep over the ground, fall into the bottom of the trenches, and enter the shelters, driving out the occupants, who would then come under the fire of the high-explosive shells. This gas, being, moreover, only suffocating, would afterwards have the advantage of not incommoding our soldiers in their trench or during the attack.
While the heavy artillery may be replaced very advantageously by torpedoes for the preparation on the continuous line of trenches, it may be employed effectively against the centers of resistance, where its more concentrated effects will not produce the simply superficial disorganization of the 75, which leaves the cupolas of the machine guns intact.
The most important part to destroy in the centers of resistance are the edges, for the attack breaks through easily enough in the intermediate spaces but immediately comes under flanking fire. Moreover, a center of resistance whose borders are disorganized, becomes a harmless island, the attack of which by main strength would be terribly costly; for instance, the Labyrinth, Neuville-Saint-Vaast, Carency, which were passed by in less than an hour by groups arriving at the Cemetery of Neuville, at the La Folie Woods, and at the first houses of Souchez. Therefore try especially to neutralize the borders by concentrating on them the fire of batteries suitably placed with a view to following the attack on the intervals. If one could put a veil over the centers of resistance to isolate them and obstruct the view of the flanking works, the problem would be partly solved. It would then be necessary to have projectiles giving off large quantities of heavy smoke, which would spread out over the ground and dissipate very slowly.