HMS Ocean ( 1862 ) HMS " Ocean " was the last of the Royal Navy ' s four s to be completed in the mid - 1860s . She was originally laid down as a 91 - gun second - rate ship of the line , and was converted during construction to an armoured frigate . The ship spent the bulk of her career on the China Station and served as flagship there for a time . Upon her return to Great Britain in 1872 her hull was found to be partly rotten and she was placed in reserve until she was sold for scrap in 1882 . Design and description . HMS " Ocean " was long between perpendiculars and had a beam of . The ship had a draught of forward and aft . She displaced . " Ocean " had a metacentric height of which meant that she rolled a lot and was an unsteady gun platform . Her hull was sheathed with Muntz metal to reduce biofouling . Her crew consisted of 605 officers and enlisted men . Propulsion . " Ocean " had a simple horizontal 2 - cylinder horizontal return connecting - rod steam engine driving a single propeller shaft using steam was provided by eight rectangular boilers . The engine produced during the ship ' s sea trials in June 1864 which gave the ship a maximum speed of . " Ocean " carried a maximum of of coal , enough to steam at . She was barque - rigged with three masts and had a sail area of . Her best speed with the propeller disconnected and under sail alone was . Yard s were added to the ship ' s mizzenmast by 1866 and " Ocean " was given a full ship rig which she retained for the rest of her career . Armament . " Ocean " was initially armed with twenty - four rifled muzzle - loading guns . Four of these guns were mounted on the upper deck as chase gun s , two each fore and aft . The 16 - calibre seven - inch gun weighed and fired a shell . It was credited with the ability to penetrate of armour . In 1867 four of these guns were replaced by rifled muzzle - loaders . The shell of the 15 - calibre eight - inch gun weighed while the gun itself weighed . It had a muzzle velocity of and was credited with the ability to penetrate of wrought iron armour at the muzzle . Armour . The entire side of the " Prince Consort " - class ships , from the upper - deck level downwards , was protected by wrought iron armour that tapered from at the ends to amidships . The armour extended below the waterline . One small conning tower was fitted on each side of the upper deck amidships , but these proved to be untenable when the ship ' s guns were fired . The armour was backed by the sides of the ship which were thick . Service history . HMS " Ocean " was laid down on 23 August 1860 as a wooden two - deck , 90 - gun ship of the line by Devonport Dockyard . The Admiralty ordered on 5 June 1861 that she be lengthened , cut down one deck , and converted to an armoured frigate for the price of £298 , 851 . The ship was launched on 19 March 1863 and commissioned in July 1866 , but was not completed until 6 September 1866 . " Ocean " initially served with the Channel Fleet , but she was almost immediately transferred to the Mediterranean , and from there to the Far East ; she arrived in Batavia ( now Jakarta ) on 15 October 1867 . She was the only armoured ship ever to double the Cape of Good Hope under canvas alone . During this voyage " Ocean " set a record in having sailed on 26 August 1867 with cold boilers , the greatest distance ever covered under sail power by a British ironclad . " Ocean " served on the China Station for five years , 1867 – 1872 , without docking once . The ship relieved the old two - decker as station flagship in 1869 when Vice - Admiral Henry Kellett took command ; a new crew was carried out by and Captain William Hewett , VC assumed command of the ship . " Ocean " was relieved in turn by in 1872 , but drew too much water to pass through the Suez Canal . The Admiralty therefore ordered that she return home via the Cape of Good Hope using steam . The ship ' s bottom was very foul and she averaged only 4 . 5 knots ( 8 . 3 km / h ) during the voyage . " Ocean " had lost a lot of sheathing during her time in the Far East and much of her planking was in a bad state . The ship was therefore relegated to dockyard reserve until sold in 1882 .