The scene of the attack was terrible; it was one of those breaches technically termed "a covered breach," and was, it must be remembered, not a wide breach opened to daylight, but a mere crack, traversing the wall from side to side. The powder had worked like an auger. The effect of the explosion had been so tremendous that the tower was cracked for more than forty feet above the chamber of the mine; but it was only a fissure, and the practicable rent that served as a breach and afforded an entrance into the lower hall, had the effect of having been pierced by the thrust of a lance rather than cleft by a blow from an axe. It was a puncture in the side of the tower, a long, deep cut, not unlike a well, horizontal with the ground, a narrow passage twisting and turning like an intestine through a wall fifteen feet thick, a shapeless cylinder, abounding in obstacles, pitfalls, and all the débris of past explosions, where a man, blinded by the darkness and stumbling over the rubbish beneath his feet, would surely dash his head against the granite rock. Before the assailants yawned this black portal, like a cavernous mouth, whose upper and lower jaws, closely set with jagged rocks, rivalled a shark's mouth in the number of its teeth. This cavity was the only means of entrance or exit, and while the grape-shot was raining within, on the other side--that is to say, in the lower hall of the ground-floor--rose the _retirade._ The ferocity of the encounter can only be compared with the encounters of sappers in underground passages when a counter-mine has just cut across a mine, or with the cutlass butcheries that take place when in a naval battle a man-of-war is boarded. Fighting in the depths of a grave reaches the very climax of all that is dreadful. The fact that a ceiling is overhead seems to increase the horror of human slaughter. Just as the first of the assailants came surging in, the _retirade_ was wrapped in a sheet of lightning, and it seemed like the bursting of a subterranean thunder-clap, report answering report as the besiegers returned the thunder of the ambuscade. Above the uproar rose the voice of Gauvain, shouting, "Break them in!" then Lantenac's cry, "Stand firm against the enemy!" then the cry of the Imânus, "Stand by me, men of Maine!" then the clang of sabres clashing one against the other, and terrible discharges following in swift succession, dealing death on every hand. The torch fastened to the wall but dimly lighted this scene of horror. A lurid glare enveloped all objects, amid which nothing could be clearly distinguished; and those who entered were straightway struck deaf and blind,--deafened by the uproar, blinded by the smoke. The disabled lay here and there among the rubbish; while the combatants trampled upon the corpses, crushing the wounds and bruising the broken limbs of the injured men, who groaned aloud in their wild agony, and sometimes set their teeth in the feet of those who were torturing them.