The Royal Navy's Victoria class (or Sans Pareil class) of the 1880s was the first class of ironclad warship (sometimes described as a battleship) which used triple expansion steam engines, previous classes having used compound engines. There were only two ships in this class. The lead ship, , was sunk in an accidental collision with another Royal Navy battleship, HMS Camperdown in the Mediterranean Sea with the loss of half of her crew. Her sister ship, , survived until she was scrapped in April 1907. Design This class was intended to be an improved version of , and it was originally called the new Conquerors. Armament The original intention had been to fit 13.5 inch (343 mm), 67-ton guns in place of the Conquerors 12 inch (305 mm) guns in the single forward turret but late during the design it was decided to enlarge them to take the 16.25 inch (413 mm), 110-ton gun. Similar guns had been supplied by the manufacturer, Sir W. G. Armstrong, Whitworth & Co., Ltd., to the Italian Regia Marina and fitted in the and the 1,800 pound (816 kg) projectile could penetrate any thickness of armour afloat at that time. At a period when naval supremacy of the Mediterranean was seen as a crucial part of British policy, the Victoria class was intended for service as part of the British Mediterranean Fleet. The same model of gun had been fitted in the last , which had a single example in each of its two barbettes instead of pairs of 13.5 inch (343 mm) guns and was the only other British warship to carry them. The gun was not successful in service since it took four or five minutes to load and fire. The barrel only had a 75-round life and the muzzle tended to droop. The rear turret contained a smaller 10 inch (254 mm) gun of similar design, and which weighed 26 tons. Seakeeping This class was one of the last of this period to have very low freeboard, of around 10 feet (3 m). This was done to reduce target area in a naval engagement but had a deleterious effect upon seaworthiness, and was an important factor in Victoria sinking within fifteen minutes following a collision since it allowed the water to quickly reach the gun turret ports. Propulsion The most successful innovation of the class was the introduction of triple expansion