Developed in the middle of the nineteenth century, the open hearth or 'Siemens-Martins process', as it is known, accounted for a major proportion of UK steel production until the early 1970s. For economic and quality reasons it has been replaced by the 'Electric Arc Furnace' and the 'Basic Oxygen Steel Making process'. There are no open hearth furnaces in use in Britain today but they are still in use in Russia and Eastern Europe.