The British admiralty, in 1843, had duplicated the Stevens experiments, using a target of 14 plates of boiler iron riveted together, which gave a total thickness of 6 inches; and experiments on laminated plating had been also at this time carried on at Gavres, in France. In 1845 Dupuy de Lôme, the famous naval architect, submitted to the French government the first European design for an armored frigate. His plans were, however, rejected; and only with the outbreak of the Crimean War was the construction of armored vessels begun. On October 17, 1855, the three French batteries which were the first results of this new departure went into action off Kinburn, in the Crimea, silencing in four hours forts which had held at bay the combined fleets of England and France. Armor had won its first victory, and had shown most signally its position as one of the main factors in the warship design of the years which were to come. These vessels, with three similar batteries constructed immediately thereafter by the British government, were clad with solid iron plates 4½ inches thick, backed by 27¾ inches of oak, comparative experiments at Vincennes, France, having shown the marked superiority of solid over laminated plating. They were, however, in but a most limited sense sea-going ships, their low speed and other inferior qualities being radical defects as to this. France led in a further advance, beginning in 1857 and completing in 1859 the transformation of the wooden line-of-battle ship Napoleon into the armored vessel of 5000 tons, which, as La Gloire, is famous as the first sea-going ironclad. She carried a strake of 4¾-inch plating at the water line, and 4½-inch plates in wake of the battery. England answered the challenge of her hereditary foe with the Warrior, an iron vessel of 9210 tons, completed in 1861. While her rival had a fully armored side, but 212 of the Warrior’s 380 feet of length carried plating. Its thickness was 4½ inches. [Illustration: _“La Gloire” (France) 1857. Side Armor Iron 4½ in. Solid._ _“Warrior” (England) 1859. Side Armor Iron 4½ in. Solid._ _U.S. Monitor “Passaic” 1862. Side Armor Iron 3 to 5 in. Laminated. Turret Armor Iron 11 in. Laminated._ _“Inflexible” (England) 1876. Belt & Citadel Armor Iron Sandwiched._ _“Duilio” (Italy) 1876. Belt Armor Steel Solid._ _U.S. Battleship Oregon. Belt Armor Harveyed Nickel Steel Solid. 13 in. Turret Armor Harveyed Nickel Steel Solid._ PLATE VIII. THE GROWTH OF ARMOR. ]