Bessemer, Sir Henry. Civil engineer and inventor. Born at Charlton, Herts., in 1813. Of his many inventions, the chief is the process named after him, of converting pig-iron into steel at once by blowing a blast of air through the iron while in fusion until everything extraneous is expelled and only a definite quantity of carbon is left in combination. This process revolutionized the iron and steel trade all over the world-leading, as has been calculated, to the production of thirty times as much steel as before, and at one-fifth the cost per ton. Died 1898.