On the evening of April 16, 1863, the Union's Mississippi River Squadron under the command of (acting) Rear Admiral David Dixon Porter ran downriver past the Confederate batteries defending Vicksburg, Mississippi. After the war, Ulysses S. Grant recalled the incident in his memoirs.
I had had in contemplation the whole winter the movement by land to a point below Vicksburg from which to operate, subject only to the possible but not expected success of some one of the expedients resorted to for the purpose of giving us a different base. This could not be undertaken until the waters receded. I did not therefore communicate this plan, even to an officer of my staff, until it was necessary to make preparations for the start. My recollection is that Admiral Porter was the first one to whom I mentioned it. The co-operation of the navy was absolutely essential to the success (even to the contemplation) of such an enterprise. I had no more authority to command Porter than he had to command me. It was necessary to have part of his fleet below Vicksburg if the troops went there. Steamers to use as ferries were also essential. The navy was the only escort and protection for these steamers, all of which in getting below had to run about fourteen miles of batteries. Porter fell into the plan at once, and suggested that he had better superintend the preparation of the steamers selected to run the batteries, as sailors would probably understand the work better than soldiers. I was glad to accept his proposition, not only because I admitted his argument, but because it would enable me to keep from the enemy a little longer our designs. Porter's fleet was on the east side of the river above the mouth of the Yazoo, entirely concealed from the enemy by the dense forests that intervened. Even spies could not get near him, on account of the undergrowth and overflowed lands. Suspicions of some mysterious movements were aroused. Our river guards discovered one day a small skiff moving quietly and mysteriously up the river near the east shore, from the direction of Vicksburg, towards the fleet. On overhauling the boat they found a small white flag, not much larger than a handkerchief, set up in the stern, no doubt intended as a flag of truce in case of discovery. The boat, crew and passengers were brought ashore to me. The chief personage aboard proved to be Jacob Thompson, Secretary of the Interior under the administration of President Buchanan. After a pleasant conversation of half an hour or more I allowed the boat and crew, passengers and all, to return to Vicksburg, without creating a suspicion that there was a doubt in my mind as to the good faith of Mr. Thompson and his flag.
Admiral Porter proceeded with the preparation of the steamers for their hazardous passage of the enemy's batteries. The great essential was to protect the boilers from the enemy's shot, and to conceal the fires under the boilers from view. This he accomplished by loading the steamers, between the guards and boilers on the boiler deck up to the deck above, with bales of hay and cotton, and the deck in front of the boilers in the same way, adding sacks of grain. The hay and grain would be wanted below, and could not be transported in sufficient quantity by the muddy roads over which we expected to march.
Before this I had been collecting, from St. Louis and Chicago, yawls and barges to be used as ferries when we got below. By the 16th of April Porter was ready to start on his perilous trip. The advance, flagship Benton, Porter commanding, started at ten o'clock at night, followed at intervals of a few minutes by the Lafayette with a captured steamer, the Price, lashed to her side, the Louisville, Mound City, Pittsburgh and Carondelet—all of these being naval vessels. Next came the transports—Forest Queen, Silver Wave and Henry Clay, each towing barges loaded with coal to be used as fuel by the naval and transport steamers when below the batteries. The gunboat Tuscumbia brought up the rear. Soon after the start a battery between Vicksburg and Warrenton opened fire across the intervening peninsula, followed by the upper batteries, and then by batteries all along the line. The gunboats ran up close under the bluffs, delivering their fire in return at short distances, probably without much effect. They were under fire for more than two hours and every vessel was struck many times, but with little damage to the gunboats. The transports did not fare so well. The Henry Clay was disabled and deserted by her crew. Soon after a shell burst in the cotton packed about the boilers, set the vessel on fire and burned her to the water's edge. The burning mass, however, floated down to Carthage before grounding, as did also one of the barges in tow.
The enemy were evidently expecting our fleet, for they were ready to light up the river by means of bonfires on the east side and by firing houses on the point of land opposite the city on the Louisiana side. The sight was magnificent, but terrible. I witnessed it from the deck of a river transport, run out into the middle of the river and as low down as it was prudent to go. My mind was much relieved when I learned that no one on the transports had been killed and but few, if any, wounded. During the running of the batteries men were stationed in the holds of the transports to partially stop with cotton shot-holes that might be made in the hulls. All damage was afterwards soon repaired under the direction of Admiral Porter.