Sample of Bessemer steel, one slice cut from the muzzle of a gun section, 2.5" x 1.375", and bent cold under the steam hammer, 1860

Sir Henry Bessemer (1813-1898) was an English inventor and engineer who invented a cheap process for manufacturing steel. He patented a process in 1856 by which molten pig iron was converted to steel by blowing air through it in a Bessemer converter.This removed most of the impurities and no extra fuel was required, because the carbon, oxidised during the blow, generated great heat. Establishing a steelworks in Sheffield, England, Bessemer manufactured guns and, later, steel rails.However further improvements were made by Robert Mushet and Sidney Gilchrist Thomas in 1878. In the USA, industrialists like Andrew Carnegie made a fortune from the process.