Bessemer, Henry (1813-1898)

In a Bessemer converter, a blast of high-pressure air oxidizes impurities in molten iron and converts it to steel.

English engineer and inventor who developed a method of converting molten pig iron into steel (the Bessemer process) in 1856. Knighted 1879.

Bessemer was born near Hitchin, Hertfordshire, and moved to London. His early inventions included a typesetting machine, new ways of making gold paint and lead pencils, and machinery for sugar refining.

During the Crimean War of the early 1850s Bessemer turned to the problem of high gas pressures causing guns to explode. The British military commanders showed no interest in Bessemer's work which was as yet unsuccessful owing to the use of phosphoric iron, but Napoleon III of France encouraged Bessemer in his experiments. By modifying the standard process, he found a way to produce steel without an intermediate wrought-iron stage, reducing its cost dramatically. However, to obtain high-quality steel, phosphorus-free ore was required. In 1860 Bessemer erected his own steel works in Sheffield, importing phosphorus-free iron ore from Sweden.