and a Gatling gun. The ship was designed to withstand hits by guns. Her hull was protected by a wrought-iron armored belt that extended below the waterline that was backed by about 15 inches of teak. The hull armor was amidships and tapered to towards the bow and stern. Above it was a strake of armor thick. The bow turret was protected with armor and the amidships turret was fitted with armor plates. The power plant consisted of a pair of Mazeline horizontal two-cylinder single-expansion steam engines, each driving a four-bladed, screw using steam provided by two Mazeline tubular boilers. The engines were rated at a total of . The ship reached a maximum speed of during her sea trials on 9 October 1864. She had an estimated range of with a full load of of coal. Origins and career In June 1863, John Slidell, the Confederate commissioner to France, asked Emperor Napoleon III in a private audience if it would be possible for the Confederate government to build ironclad warships in France. Arming ships of war for a recognized belligerent like the Confederate States would have been illegal under French law, but Slidell and his agent, James D. Bulloch, were confident that the Emperor of France would be able to circumvent his own laws more easily than other potential secret contractors. Napoleon III agreed to the building of ironclads in France on the condition that their destination remain a secret. The following month Bulloch entered a contract with Lucien Arman, a French shipbuilder and a personal confidant of Napoleon III, to build a pair of ironclad rams capable of breaking the Union blockade. To avoid suspicion, the ships' guns were manufactured separately from the ship herself and the pair were named Cheops and Sphinx to encourage rumors that they were intended for the Egyptian Navy. Prior to delivery, however, a shipyard clerk walked into the U.S. Minister's office in Paris and produced documents which revealed that Arman had fraudulently obtained authorization to arm the ships and was in contact with Confederate agents. The French government blocked the sale under pressure from the United States, but Arman was able to sell the ships to Denmark and Prussia, which were then fighting on opposite sides of the Second Schleswig War. Cheops was sold to Prussia as , while Sphinx was sold to Denmark under the name Stærkodder on 31 March 1864.