Among the vessels France acquired was the _Dunderberg_, which was renamed _Rochambeau_ by her new owners. It consisted of a long iron fortress mounted with guns to fire on the broadside and also ahead and astern. The hull, also of iron, was but little above the water, and the decks were iron-plated. The central portion had armour 7 inches thick with a heavy wooden backing, and the decks fore and aft of the fortress were plated 8½ inches thick. Her two engines, developing 5,000 h.p., gave her at a pinch a speed of between eleven and twelve knots, but when she crossed the ocean she made the voyage under her own steam at between eight and nine knots. The after part, containing the screw propeller and steering gear, was also shot-proof. She had an immense beak or ram. Her total length was 378 feet, her breadth 73 feet, and her depth 81 feet, and she drew 22 feet of water. As purchased by the French she had an armament of five 15-inch Rodman guns, and twelve 11-inch Dahlgrens. Another vessel, the _Onondaga_, was also purchased from America by the French, and both were altered at Cherbourg to meet French views. When the French decided to adopt ironclad ships carrying a very few guns of great power, they did not hesitate to make some extraordinary experiments. One of their vessels, built in 1866, was the _Taureau_. It was like nothing that had been afloat before or has been launched since. Viewed from the stern, it resembled a sphere with a deck-house, a couple of masts, and a chimney. Much the same aspect was presented by a front view, except that before the deck-house was a small turret in which was one large gun. The turret was carried very far forward and could be revolved so that the gun had almost an all-round fire, the only limitation being the funnel and deck erections. The bow was extended enormously from the deck level to some distance below the water, and projected no less than 40 feet under the surface. The turret was not built on the deck, but descended to the bottom of the hold, and was protected by nearly 5 inches of armour, and a similar thickness was placed over the bows. The sides were plated 3 feet above the water-line, this belt extending to the stern. The engines were of 250 h.p. The _Taureau_ was about 48 feet maximum width, and 197 feet in length without the ram. The idea underlying the construction of this unwieldy ship was that she should be able to deliver a heavy shot at close range to an enemy’s ship, and follow this up by ramming it, thereby completing its destruction; while her convex bows and circular turret would present no plane surface to the enemy, so that any shot which might strike it could only give a glancing blow and bound away harmlessly.