steam engines into Royal Navy battleships. These engines had been developed as a result of the introduction of steel in boiler manufacture, which in turn had led to higher steam pressures. The Royal Navy had originally tried them with great success in the torpedo gunboat . The principal benefit was the improved efficiency of the engine meant a reduced displacement because less coal was needed. In trials, , which had been re-engined with triple-expansion engines in 1889–1891, showed that the coal consumption at 80% power was roughly halved. Ships References Bibliography David Brown, Warrior to Dreadnought: Warship development 1860–1905, Chatham Publishing. External links Battleship classes Ship classes of the Royal Navy