Mortar-firing, however good, would not reduce the forts, nor lay New Orleans at the mercy of the fleet. It was necessary to pass above. Neither the flag-officer on the one hand, nor the leaders of the enemy on the other had any serious doubt that the ships could go by if there were no obstructions; but the obstructions were there. As originally laid these had been most formidable. Cypress trees, forty feet long and four to five feet in diameter, were laid longitudinally in the river, about three feet apart to allow a water-way. Suspended from the lower side of these logs by heavy iron staples were two 2½-inch iron cables, stretching from one side of the river to the other. To give the framework of trunks greater rigidity, large timbers, six by four inches, were pinned down on the upper sides. The cables were secured on the left bank to trees; on the right bank, where there were no trees, to great anchors buried in the ground. Between the two ends the raft was held up against the current by twenty-five or thirty 3,000-pound anchors, with sixty fathoms of chain on each. This raft, placed early in the winter, showed signs of giving in February, when the spring-floods came sweeping enormous masses of drift upon it, and by the 10th of March the cables had snapped, leaving about a third of the river open. Colonel Higgins was then directed to restore it. He found it had broken from both sides, and attempted to replace it by sections, but the current, then running four knots an hour, made it impossible to hold so heavy a structure in a depth of one hundred and thirty feet and in a bottom of shifting sand, which gave no sufficient holding ground for the anchors. Seven or eight heavily built schooners, of about two hundred tons, were then seized and placed in a line across the river in the position of the raft. Each schooner lay with two anchors down and sixty fathoms of cable on each; the masts were unstepped and, with the rigging, allowed to drift astern to foul the screws of vessels attempting to pass. Two or three 1-inch chains were stretched across from schooner to schooner, and from them to sections of the old raft remaining near either shore.
Such was the general character of the obstructions before the fleet. The current, and collisions with their own vessels, had somewhat disarranged the apparatus, but it was essentially in this condition when the bombardment began. It was formidable, not on account of its intrinsic strength, but because of the swift current down and the slowness of the ships below, which, together, would prevent them from striking it a blow of sufficient power to break through. If they failed thus to force their way they would be held under the fire of the forts, powerless to advance.
It is believed that, in a discussion about removing the obstructions, Lieutenant Caldwell, commanding the Itasca, volunteered to attempt it with another vessel, and suggested taking out the masts of the two. The Itasca and the Pinola, Lieutenant-Commanding Crosby, were assigned to the duty, and Fleet-Captain Bell given command of both; a rather unnecessary step, considering the age and character of the commanders of the vessels. To handle two vessels in such an enterprise, necessarily undertaken on a dark night, is not easy, and it is a hardship to a commander to be virtually superseded in his own ship at such a time. This was also felt in assigning divisional commanders for the night attack only, when they could not possibly manage more than one ship and simply overshadowed the captain of the vessel.
On the afternoon of the 20th, the Itasca and Pinola each went alongside one of the sloops, where their lower masts were taken out, and, with the rigging, sent ashore. At 10 P.M. Captain Bell went aboard both and addressed the officers and crews about the importance of the duty before them. He remained on board the Pinola and the two vessels then got underway, the Pinola leading. All the mortar-boats now opened together, having at times nine shells in the air at once, to keep down the fire of Jackson in case of discovery, although the two gunboats showed for little, being very deep in the water.
As they drew near the obstructions two rockets were thrown up by the enemy, whose fire opened briskly; but the masts being out, it was not easy to distinguish the vessels from the hulks. The Pinola struck the third from the eastern shore and her men jumped on board. The intention was to explode two charges of powder with a slow match over the chains, and a torpedo by electricity under the bows of the hulk, a petard operator being on board. The charges were placed, and the Pinola cast off. The operator claims that he asked Bell to drop astern by a hawser, but that instead of so doing, he let go and backed the engines. Be this as it may, the ship went rapidly astern, the operator did not or could not reel off rapidly enough, and the wires broke. This hulk therefore remained in place, for the timed fuzes did not act.
The Itasca ran alongside the second hulk from the east shore and threw a grapnel on board, which caught firmly in the rail; but through the strength of the current the rail gave way and the Itasca, taking a sheer to starboard, drifted astern with her head toward the bank. As quickly as possible she turned round, steamed up again and boarded the hulk nearest the east shore on its port, or off-shore side, and this time held on, keeping the engine turning slowly and the helm aport to ease the strain on the grapnel. Captain Caldwell, Acting-Masters Amos Johnson and Edmund Jones, with parties of seamen, jumped on board with powder-cans and fuzes; but, as they were looking for the chains, it was found that they were secured at the bows, by lashing or otherwise, to the hulk's anchor chain, the end of the latter being led in through the hawse-pipe, around the windlass and bitted. When its windings had been followed up and understood, Captain Caldwell was told that the chain could be slipped. He then contemplated firing the hulk, but while the materials for doing so were sought for, the chain was slipped without orders. The vessels went adrift, and, as the Itasca's helm was to port and the engines going ahead, they turned inshore and grounded hard and fast a short distance below, within easy range of both forts.
A boat was at once sent to the Pinola, which was steaming up to try again, and she came to her consort's assistance. Two lines were successfully run to the Itasca, but she had grounded so hard that both parted, though the second was an 11-inch hawser. The Pinola now drifted so far down, and was so long in returning, that the Itasca thought herself deserted; and the executive officer, Lieutenant George B. Bacon, was despatched to the Hartford for a more powerful vessel. The hour for the moon to rise was also fast approaching and the fate of the Itasca seemed very doubtful.
The Pinola, however, came back, having in her absence broken out a 13-inch hawser, the end of which was passed to the grounded vessel. The third trial was happy and the Pinola dragged the Itasca off, at the same time swinging her head up the river. Lieutenant Caldwell, who was on the bridge, when he saw his ship afloat, instead of returning at once, steadied her head up stream and went ahead fast with the engines. The Itasca moved on, not indeed swiftly, but firmly toward and above the line of hulks, hugging the eastern bank. When well above Caldwell gave the order, "Starboard;" the little vessel whirled quickly round and steered straight for the chains. Carrying the full force of the current with her and going at the top of her own speed, she passed between the third hulk, which the Pinola had grappled, and the fourth. As her stem met the chain she slid bodily up, rising three or four feet from the water, and dragging down the anchors of the hulks on either side; then the chains snapped, the Itasca went through, and the channel of the river was free.
The following morning the hulks were found to be greatly shifted from their previous positions. The second from the east shore remained in place, but the third had dragged down and was now astern of the second, as though hanging to it. The hulk nearest the west shore was also unmoved, but the other three had dragged down and were lying more or less below, apparently in a quartering direction from the first. A broad open space intervened between the two groups. The value of Caldwell's work was well summed up by General M.L. Smith, the Confederate Engineer of the Department: "The forts, in my judgment, were impregnable so long as they were in free and open communication with the city. This communication was not endangered while the obstruction existed. The conclusion, then, is briefly this: While the obstruction existed the city was safe; when it was swept away, as the defences then existed, it was in the enemy's power."
The bombardment continued on the 21st, 22d, and 23d with undiminished vigor, but without noteworthy incident in the fleet. The testimony of the Confederate officers, alike in the forts and afloat, is unanimous as to the singular accuracy of the mortar fire. A large proportion of the shells fell within the walls of Jackson. The damage done to the masonry was not irreparable, but the quarters and citadel, as already stated, were burned down and the magazine endangered. The garrison were compelled to live in the casemates, which were partially flooded from the high state of the river and the cutting of the levee by shells. Much of the bedding and clothing were lost by the fire, thus adding to the privations and discomfort. On the 21st Jackson was in need of extensive repairs almost everywhere, and the officers in command hoped that the Louisiana, which had come down the night before, would be able to keep down the mortar fire, at least in part. When it was found she had no motive power they asked that she should take position below the obstructions on the St. Philip side, where she would be under the guns of the forts, but able to reach the schooners. If she could not be a ship of war, at least let her be a floating battery. Mitchell declined for several reasons. If a mortar-shell fell vertically on the decks of the Louisiana it would go through her bottom and sink her; the mechanics were still busy on board and could not work to advantage under fire; the ports were too small to give elevation to the guns, and so they could not reach the mortars. If this last were correct no other reason was needed; but as the nearest schooner was but 3,000 yards from Jackson, it seems likely he deceived himself, as he certainly did in believing "on credible information" that a rifled gun on the parapet of Jackson, of the same calibre as that of the Louisiana, had not been able to reach. Three schooners had been struck, one at the distance of 4,000 yards, during the first two days of the bombardment, not only by rifled, but by VIII-and X-inch spherical projectiles; and the second division had been compelled to shift its position. Looking only to the Louisiana, the decision of the naval officers was natural enough; but considering that time pressed, that after five days' bombardment the fleet must soon attack, that it was improbable, if New Orleans fell, that the Louisiana's engines could be made efficient and she herself anything but a movable battery, the refusal to make the desired effort looks like caring for a part, at the sacrifice of the whole, of the defence. On the last day Mitchell had repeated warnings that the attack would soon come off, and was again asked to take a position to enfilade the schooners, so that the cannoneers of Jackson might be able to stand to their guns. Mitchell sent back word that he hoped to move in twenty-four hours, and received from Higgins, himself an old seaman and naval officer, the ominous rejoinder: "Tell Captain Mitchell that there will be no tomorrow for New Orleans, unless he immediately takes up the position assigned to him with the Louisiana."[5]