MAP OF FORT HENRY, FEBRUARY 6, 1862.

      At the hour designated the troops and gunboats started. General Smith found Fort Heiman had been evacuated before his men arrived. The gunboats soon engaged the water batteries at very close quarters, but the troops which were to invest Fort Henry were delayed for want of roads, as well as by the dense forest and the high water in what would in dry weather have been unimportant beds of streams. This delay made no difference in the result. On our first appearance Tilghman had sent his entire command, with the exception of about one hundred men left to man the guns in the fort, to the outworks on the road to Dover and Donelson, so as to have them out of range of the guns of our navy; and before any attack on the 6th he had ordered them to retreat on Donelson. He stated in his subsequent report that the defence was intended solely to give his troops time to make their escape.

      Tilghman was captured with his staff and ninety men, as well as the armament of the fort, the ammunition and whatever stores were there. Our cavalry pursued the retreating column towards Donelson and picked up two guns and a few stragglers; but the enemy had so much the start, that the pursuing force did not get in sight of any except the stragglers.

      All the gunboats engaged were hit many times. The damage, however, beyond what could be repaired by a small expenditure of money, was slight, except to the Essex. A shell penetrated the boiler of that vessel and exploded it, killing and wounding forty-eight men, nineteen of whom were soldiers who had been detailed to act with the navy. On several occasions during the war such details were made when the complement of men with the navy was insufficient for the duty before them. After the fall of Fort Henry Captain Phelps, commanding the iron-clad Carondelet, at my request ascended the Tennessee River and thoroughly destroyed the bridge of the Memphis and Ohio Railroad.