The aerial torpedo, on the contrary, seems to produce terrifying effects on the defenders of the trenches; it has also considerable destructive effect. This power is not always sufficient to break in the shelter caverns, but it completely knocks to pieces the firing trenches, produces cave-ins, blocks the openings of the shelters, and thus walls in the occupants. By its formidable explosion, the extraordinary effects of its blast, and the concussion that it induces in the ground, it annihilates all energy in the defenders, who at every instant think their last minute has come. In the sector of attack of my company on the 9th of May, a portion of the trenches in front of the 3d and 4th Sections was severely pounded by the fire of the 75 and especially by the aerial torpedoes, while the remainder of the trenches in front of the 1st and 2d Sections suffered only from the preparation by the 75. The difference was remarkable. While the 1st and 2d Sections, hardly out of their parallel, saw the enemy rise up and melted away under his suddenly opened rifle fire, and especially under that of a machine gun, the 4th Section reached the German trench, crossed it without hindrance, and continued on its way. As for the 3d Section, it had been received by only a few shots and had crossed the first trench in one rush, when it received some shots in the back. Returning to the rear, the men found several dozen Germans crouching in the deep shelters, absolutely all in and crying for mercy. The cannonade had ceased, and in spite of the violent fusillade cracking outside announcing an attack, they had not budged. Only a few had the courage to shoot in the back from an opening the French soldiers who passed close by. Conversations with numerous infantry officers have definitely convinced me that the heaviest bombardment by 75’s alone is ineffective against trenches organized during a long period. The heavy artillery has too much dispersion, while the aerial torpedo, besides its considerable destructive and demoralizing effects, is very accurate. Thus the preparation on the zone of the first trenches may be made largely by means of aerial torpedoes. But it is necessary that the torpedo guns be placed close together in a continuous line (at least one to every 100 metres of trenches) and that each one have its zone clearly defined. At Arras, these guns were not very numerous, and their preparation was consequently only partial; in trying to pound several lines of trenches at the same time, large spaces remained outside the effects of their action, while certain corners were entirely demolished. 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.