(SwGbt: l. 252'; b. 30'; dr. 6'; dph. 6'; s. 9 k.; cpl. 65 to 94; a. 2 9" s.b., 1 8" s.b., 1 6.4" r.)
CSS Selma was a coastwise packet built at Mobile for the Mobile Mail Line in 1856. Little doubt now remains that she was originally named Florida. As the latter, she was inspected and accepted by Capt. Lawrence Rousseau, CSN, 22 April 1861, acquired by the Confederacy in June, cut down and strengthened by hog frames and armed as a gunboat—all, apparently, in the Lake Ponchartrain area. Her upper deck was plated at this time with ⅜"-iron, partially protecting her boilers, of the low pressure type preferred for fuel economy and greater safety in battle. CSS Florida is cited on 12 November 1861 as already in commission and serving Commodore Rollins' New Orleans defense flotilla under command of Lt. Charles W. Hays, CSN.
The Mobile Evening News editorialized early in December on the startling change "from her former gay, first-class hotel appearance, having been relieved of her upper works and painted as black as the inside of her smokestack. She carries a jib forward and, we suppose, some steering sail aft, when requisite."
Although much of Florida's time was spent blockaded in Mobile, she made some forays into Mississippi Sound, two of which alarmed the U.S. Navy's entire Gulf command: On 19 October Florida convoyed a merchantman outside. Fortunately for her the coast was clear of Union ships and batteries, for Florida fouled the area's main military telegraph line with her anchor and had no sooner repaired the damage than she went aground for 36 hours. Luck returning, she tried out her guns on USS Massachusetts, "a large three-masted propeller" she mistook for the faster R. R. Cuyler. Being of shallower draft and greater speed, she successfully dodged Massachusetts in shoal water off Ship Island. The havoc caused by one well-placed shot with her rifled pivot gun is described by Commander Melancton Smith, USN, commanding Massachusetts: "It entered the starboard side abaft the engine five feet above the water line, cutting entirely through 18 planks of the main deck, carried away the table, sofas, eight sections of iron steam pipe, and exploded in the stateroom on the port side, stripping the bulkheads of four rooms, and setting fire to the vessel ... 12 pieces of the fragments have been collected and weigh 58 pounds."
The first sortie by Florida caused consternation. Capt. L. M. Powell, USN, in command at Ship Island—soon to be main advance base for the New Orleans campaign— wrote to Flag Officer McKean, 22 October, "The first of the reported gun steamers made her experimental trial trip on the Massachusetts, and, if she be a sample of the rest, you may perhaps consider that Ship Island and the adjacent waters will require a force of a special kind in order to hold them to our use…. The caliber and long range of the rifled cannon from which the shell that exploded in the Massachusetts was fired established the ability of these fast steam gunboats to keep out of the range of all broadside guns, and enables them to disregard the armament or magnitude of all ships thus armed, or indeed any number of them, when sheltered by shoal water."
Protecting CSS Pamlico, in contrasting white dress and laden with some 400 troops, "the black rebel steamer" Florida on 4 December had a brush with USS Montgomery in Horn Island Pass that caused jubilation in the Southern press. Comdr. T. Darrah Shaw of Montgomery, finding his 10-inch shell gun no match for Florida's long-range rifles, signaled Comdr. Melancton Smith for assistance, and when it was not forthcoming, ran back to safety under the guns of Ship Island. Shaw saved Montgomery and lost his command for fleeing from the enemy: Commodore McKean promptly sent Lieutenant Jouett to relieve him and forwarded Shaw's action report to Secretary Welles, noting, "It needs no comment." Crowed Richmond Dispatch on 14 December, quoting Mobile Evening News, "The Florida fought at great disadvantage in one respect, owing to her steering apparatus being out of order, but showed a decided superiority in the effectiveness of her armament. That gun which scared the Massachusetts so badly, and had nearly proved fatal to her, is evidently a better piece or must be better handled than any which the enemy have." With the advent of cruiser Florida, she was renamed Selma, in July 1862, Lt. Peter U. Murphey, CSN, assuming command.
On 5 February 1863, while steaming down Mobile Bay with 100 extra men in search of a blockader to carry by boarding, Selma was bilged by a snag in crossing Dog River Bar, entrance to Mobile, and sank in 8 feet of water. Pumped out hastily, she was back in service the 13th.
By the following year, Selma, Morgan and Gaines, the only ships capable of defending lower Mobile Bay, were having a serious problem with deserting seamen, and intelligence reported Selma's crew as having fallen as low as 15 men about mid-February. At the crucial battle of 5 August 1864, Selma particularly annoyed Farragut by a steady, raking fire as she stood off Hartford's bow. After passing the forts, Farragut ordered gunboat Metacomet cast loose from Hartford to pursue the Selma. After an hour-long running fight, Murphey, unable to escape to shallows out of reach, had to surrender to faster, more heavily armed Metacomet. Selma lost 7 killed and 8 wounded, including her captain.
She was sold at New Orleans, 12 July 1865, being redocumented as a merchant ship the following month.