The enemy made a desperate effort to recover what he had lost, and the battle became general again; but no permanent advantage was secured. Lee retired to his inner line of intrenchments, which he had strengthened so that a direct assault was not practicable. For a week, while the roads were rendered unfit for use by heavy rains, the two armies confronted each other. Grant watched for an opportunity to turn the enemy's position, but his wily foe as often discovered his purpose. It was manifest that no brilliant results were to be achieved at Spottsylvania, and Grant made up his mind to "fick it again." A new flank movement was begun, and the lieutenant general safely moved his army "on to Richmond," across the North Anna River, where its passage was disputed by the rebels; but they were driven back, and the nationals crossed the stream, posting themselves in a strong position. In the mean time, Grant had changed his base of supplies from Fredericksburg to White House, on the Pamunkey. Sheridan had returned from his raid, and was rendering efficient service in protecting the supplies with his cavalry, and in reconnoitring the positions of the enemy. Lee, who had been over all this ground before, in the memorable campaign with McClellan, and knew from experience what strong places the region contained, was found to be even more securely placed than before. Grant therefore decided not to attack him in his intrenchments, but, under cover of a feint, recrossed the North Anna, marched along its banks till he reached the Pamunkey, of which the former river is a branch, crossing it near Hanover Court House, only sixteen miles from Richmond. The rebels still kept up with the movement, occupying their intrenchments made to cover Richmond. They were posted on the Chickahominy, which Grant was obliged to cross if he reached the city. He decided to make the attempt to break the enemy's line at Cold Harbor, where roads were available from White House and to the rebel capital. The attack was made, and one of the severest battles of the campaign followed. Sheridan had taken possession of the place, and the enemy attempted to drive him out. The Sixth Corps went to his assistance, and the spot was held. Two days later, four o'clock in the morning, a general assault was made. The first line of the rebel works was carried by Hancock, but he was forced back with heavy losses. The conflict raged with unabated fury till half past one in the afternoon, when the weary combatants rested from the strife. Grant fortified his line, but it was impossible to carry the rebel strongholds.