At half-past six o’clock, A. M., this haze cleared away. Looking towards Sewall’s Point there appeared the Merrimac and the rebel steamers Yorktown and Patrick Henry. They were stationary—the Merrimac to the right of the others, blowing off steam. Their appearance was the cause for a second alarm. The rebel craft seemed deliberating what to do—whether to move on and attempt the destruction of the Minnesota, which was aground, or to attack the Union fleet anchored near the Rip Raps. The appearance of the Merrimac on this second visit caused great precipitation in the removal of the Federal transport fleet to a safe harbor a mile or two up the Chesapeake. At seven A. M., a plan seemed to have been adopted, and the Merrimac steamed in the direction of the Minnesota, which was still aground. The Yorktown and Jamestown were crowded with troops, and steamed slowly after the Merrimac. The plan of the latter seemed to be to destroy the Minnesota, and then proceed to shell out the Union camp at Newport News, land and take possession of the camp with their own troops. The Merrimac steamed along with boldness until she was within three miles of the Minnesota, when the Monitor emerged from behind the latter, and proceeded towards the Merrimac. At first the rebel craft seemed nonplussed, and hesitated, no doubt, in astonishment at the strange-looking vessel approaching her. The Merrimac then closed the distance between her and the Monitor until they were within a mile of each other. Both batteries stopped. The Merrimac fired a shot at the Minnesota, to which no reply was made. The rebel craft then fired at the Monitor; the latter replied, hitting the Merrimac near the water line. The Merrimac then commenced firing very rapidly, first from her stern gun at the Monitor, and then her broadside guns, occasionally firing a shot at the Minnesota. The fight went on in this way for an hour or two, both vessels exchanging shots pretty freely. Sometimes the Merrimac would retire, followed by the Monitor, and _vice versa_.