The continued low water in the Red river, and the difficulty of keeping up a line of supplies, caused the army to fall back to Alexandria. The march commenced in the afternoon of April 21st, by starting the baggage train with a suitable guard. At 2 o’clock the next morning the army began silently to evacuate its position, General Smith’s force forming the rear guard. Soon after daylight, the enemy observing the movement, began his pursuit, but with so small a force that only slight skirmishing took place. The army reached Alexandria without serious fighting, on the 27th of April. * * * * * The difficulties and dangers which the naval commander was called upon to meet and overcome are worthy of more than a passing notice. During the return of the vessels through the narrow and snaggy river, they were assailed continually by rebel batteries on the shore, and were followed and attacked at all favorable points by thousands of infantry and horse artillery. On the 12th of April a severe engagement occurred, owing to an attempt, by a rebel force of two thousand men, to capture the iron-clad Osage and the transport Black Hawk, which had grounded. Flushed with their recent victory over Banks’s army, the rebels displayed unwonted courage, and soon drove all the men from the transport to the safe casemates of the monitor; but a destructive cross-fire from the Osage and Lexington quickly put them to flight with severe loss. Every day difficulties of this character occurred, as the vessels were constantly grounding, until they arrived at Grand Ecore, when greater and more serious obstacles presented themselves, which threatened the loss of the most valuable vessels of the fleet. The rebels were industriously employed in cutting off the supply of water from various channels up the river, in the hope of preventing the passage of the vessels over the bar at Grand Ecore, and the result appeared to promise success to their plans. The heavy vessels were constantly grounding, and, on the 26th of April, the commander of the Eastport, after laboring night and day for a week to carry his vessel over the sand-bars and logs by which she was clogged, was compelled to blow her up, after removing all her stores and available equipments. On the 4th of May the steamers Covington, Warner, and Signal were captured by about two thousand rebels, who attacked them from the banks of the river, killing or capturing forty of their crew. The crowning act of heroism and of engineering skill in this unfortunate campaign, is described in the report of Admiral Porter, in detailing the passage of the Falls of Alexandria by the fleet: “MISSISSIPPI SQUADRON, FLAGSHIP BLACK HAWK, } “MOUTH RED RIVER, May 16th, 1864. }