For breaching fortifications, on the other hand, curved fire is necessary; the escarps of modern fortresses are usually covered from view by screens of earth or masonry in front, so that the projectiles must pass over the crest of the screen, and drop sufficiently to strike the wall about half-way down, that is to say, at an angle of 15 deg. to 20 deg.. To destroy the wall, shell containing large bursting charges of powder are found to be particularly well adapted.
He discovered D'Hérouville leaning against a cannon, contemplating the escarps and bastions of the citadel. The marquis went forward, striking his heels soundly. D'Hérouville roused himself and turned round. "You are Monsieur le Comte d'Hérouville," began the marquis, abruptly. "I am," peering into the marquis's face, and stepping back in surprise.