Until 1858, the navies of the world were wooden vessels, but, in that year, the French applied armor-plating to the steam frigate La Gloire, whereupon the British admiralty speedily constructed the 9200-ton iron steamship, Warrior. Probable though it was that an immense change was imminent in naval construction, the United States Navy department was slow to make a venture in the direction indicated. Richmond was in advance of Washington. As early as May 8, 1861, the Confederate Secretary of the Navy wrote, I regard the possession of an iron-armored ship as a matter of the first necessity;1 and in July, he gave an order to raise the steam frigate Merrimac (one of the ships partially burned and sunk when the Gosport navy-yard was destroyed2) and convert her into an ironclad: this was accomplished as rapidly as could be expected under the imperfect manufacturing and mechanical conditions in the South.
By an act of August 3, 1861, the United States Congress constituted a naval board; four days later the Navy Department advertised for plans and offers of iron-clad steamboats of light draught suitable to navigate the shallow rivers and harbors of the Confederate States.3 John Ericsson submitted a plan which was rejected but, on the persuasion of a friend, he went to Washington and demonstrated to the entire satisfaction of the board that his design was thoroughly practical and based on sound theory.4 His proposal was accepted and Secretary Welles told him to begin the construction forthwith without awaiting the execution of the formal contract, inasmuch as the knowledge of the progress on the Merrimac had impressed the naval people