But Bragg was also an officer of great energy and activity, and he had under his command a force nearly if not quite equal to that of his foe. He was at disadvantage during Rosecrans's sudden and unexpected advance from Nashville, from the fact that he had sent away his cavalry under Wheeler, Forrest, and Morgan to assail Rosecrans's communications at a time when that general was not expected to take the initiative in a winter campaign in the field. But now that Rosecrans was in his front, and obviously intending immediate battle, Bragg in his turn determined to assume the aggressive and himself bring on the action. His plan was absolutely identical with that of Rosecrans, namely to push forward his left wing, envelope and crush his enemy's right and by successive right wheels to destroy his foe or drive him into retreat. Thus Rosecrans intended to begin the battle at one end of the line while Bragg meant to begin it at the other. Each of course massed his forces at the point where he purposed to make his first assault, and each thus weakened his line at the point which his enemy was planning to assail. As a consequence the initiatory advantage must of necessity lie with the force that should succeed in making itself the first aggressor, bringing on the battle before the other was ready and striking the other's weakest wing with his own strongest divisions. That advantage fell to Bragg as a reward for his alertness in striking as soon as possible after dawn on the last day of the year. He had so extended his left as completely to overlap Rosecrans's right and he fell upon it in flank with resistless impetuosity. The force defending it was quickly crushed and the Confederates, advancing with enthusiasm, bent back the next division encountered, and after some strenuous fighting, forced it to retire upon a new line which Rosecrans had hastily established at right angles to that of the morning. The fighting continued with desperate determination and great slaughter on both sides until nightfall. The advantage was conspicuously with the Confederates, though there was no decisive victory won. Rosecrans had held his position indeed, upon a part of his line, and had not been either destroyed or forced into retreat. But the Confederates had driven him from one half or more of the ground that he had held at the beginning of the battle, had captured twenty-eight of his guns and large numbers of prisoners, while their cavalry had marched entirely around him and fallen upon his communications in a way that very seriously threatened him with an isolation that must have involved his destruction.