Both sides fought for a long time in a heavy, smoky dusk, that was practically night. Officers coming from far points, led, compass in hand, having no other guide save the roar of battle. As the Southern leaders had foreseen, Grant was throwing in the full strength of his powerful army, hoping with superior numbers and better equipment to crush Lee utterly that day. The great Northern artillery was raking the whole Southern front. Hancock, the superb, was hurling the heavy Northern masses directly upon the main position of the South. He had half the Army of the Potomac, and at other points Warren, Wadsworth, Sedgwick and Burnside were advancing with equal energy and contempt of death. Fiercer and fiercer grew the conflict. Hancock, remembering how he had held the fatal hill at Gettysburg, and resolved to win a complete victory now, poured in regiment after regiment. But in all the fire and smoke and excitement and danger he did not neglect to keep a cool head. Hearing that a portion of Longstreet's corps was near, he sent a division and numerous heavy artillery to attack it, driving it back after a sanguinary struggle of more than an hour. Then he redoubled his attack upon the Southern center, compelling it to give ground, though slowly. Harry felt that gliding movement backward and a chill ran through his blood. The heavy masses of Grant and his powerful artillery were prevailing. The strongest portion of the Southern army was being forced back, and a gap was cut between Hill and Longstreet. Had Hancock perceived the gap that he had made he might have severed the Southern army, inflicting irretrievable retreat, but the smoke and the dusk of the Wilderness hid it, and the moment passed into one of the great "Ifs" of history. Harry, on horseback, witnessed this conflict, all the more terrible because of the theater in which it was fought. The batteries and the riflemen alike were frequently hidden by the thickets. The great banks of smoke hung low, only to be split apart incessantly by the flashes of fire from the big guns. But the bullets were more dangerous than the cannon balls and shells. They whistled and shrieked in thousands and countless thousands. Lee sat on his horse impassive, watching as well as he could the tide of battle. Messengers covered with smoke and sweat had informed him of the gap between Hill and Longstreet, and he was dispatching fresh troops to close it up. Harry saw the Invincibles march by. The two colonels at their head beheld Lee on his white horse, and their swords flew from their scabbards as they made a salute in perfect unison. Close behind them rode St. Clair and Happy Tom, and they too saluted in like manner. Lee took off his hat in reply and Harry choked. "About to die, we salute thee," he murmured under his breath.