During the days of the bombardment, the exact damage done to the forts could not be ascertained. A deserter from the garrison came to the fleet and stated that Jackson was a complete wreck, but his information was considered rather doubtful. After six days' firing, when the forts showed no disposition to surrender, and when our stock of ammunition was considerably reduced, Captain Porter submitted to the flag officer a plan for passing with the fleet between the forts. The order to pass the forts was given on the 23d of April, and a favorable reference in this order was made to Captain Porter's plan. On the morning of the 24th of April, at three o'clock, the fleet got under weigh. The steam gunboats of the flotilla ran up close to the western fort and engaged the water battery and the rampart guns, and from the mortar vessels a shower of shells was thrown into the besieged work. This bombardment made it impossible for the leaders of the enemy to keep their men on the ramparts. Three times they broke, although they were twice driven back to their guns at the point of the bayonet. From Fort St. Philip a much greater resistance was offered to the ships in their passage up between the works, as that fort had not been (comparatively speaking) so effectively attacked, nor had it suffered previously nearly so much as the other from the mortars of Captain Porter. That the resistance of Jackson was much slighter on this occasion, is further demonstrated, by the fact, that our ships received little injury from the port side (Fort Jackson), while nearly all the shot holes were found to be on the starboard, the Fort Philip side. After the fleet had thus passed the stronghold of the enemy, and destroyed ten or twelve of his armed steamers, the famous ram 'Manassas' among them, Captain Farragut gallantly ascended the river, took and occupied the quarantine, where he paroled the garrison, and then continued his course for New Orleans. In the mean time, it had been ascertained, that the iron-clad battery Louisiana, fourteen guns, and two or three other armed steamers of the enemy were still unharmed near the forts, and it appeared therefore precarious, for Captain Porter to remain with his mortar schooners (all sailing vessels) quite unprotected and liable to momentary attack from such overpowering structures. He consequently despatched them to the gulf, to watch and cut off in the rear all communication with the forts, while he remained with the few steam gunboats of the flotilla, at the station occupied during the bombardment. The Sachem, commanded by Mr. Gerdes, he had sent east of Fort St. Philip, to aid Major-General Butler in landing troops by the back bayou, leading to the quarantine. This duty was successfully executed by the coast survey party. They sounded the channel, and buoyed it out with lamps, and thus facilitated the landing of about one thousand five hundred soldiers during the night in boats and launches of the transports.