Henry Bessemer

Lore & Background

Henry Bessemer was born in the village of Charlton, near Hitchin in Hertfordshire, to Anthony Bessemer, an inventor who had been forced to leave Paris by the French Revolution. Henry was given his name by his godfather Henry Caslon, who employed his father as a punchcutter. Bessemer made his first fortune by reverse-engineering and improving a steam-powered process for making bronze powder used in gold paint, reducing the price from £5 12 shillings per pound to about 4 shillings per pound. The profits allowed him to pursue other inventions, including a method for making continuous ribbon of plate glass in 1848, which was not commercially successful.

Bessemer's attention turned to steel manufacture while trying to improve gun construction. He worked on the problem from 1850 to 1855, when he patented his method of blowing air through molten pig iron to remove impurities. He first described the process on 24 August 1856 at a meeting of the British Association in Cheltenham. Although William Kelly received a priority patent in the US in 1857, Bessemer licensed his process to five ironmasters. Initial difficulties in producing good-quality steel were overcome with the help of Robert Forester Mushet, who showed that carbon content could be controlled by adding spiegeleisen. Bessemer eventually erected his own steelworks in Sheffield in partnership with others, and his firm undersold competitors by a significant margin, leading to widespread licensing and royalties exceeding a million pounds sterling.

Reader's Guide

Bessemer's steel-making process revolutionised structural engineering by making steel easier, quicker and cheaper to manufacture. Before his invention, many industries were constrained by reliance on cast iron and wrought iron, which led to catastrophic failures such as the Dee Bridge disaster of 1847, the Wootton bridge collapse, the Bull bridge accident of 1860, and the Tay Bridge disaster of 1879. The Bessemer process allowed steel to be widely substituted for these materials, greatly improving safety and enabling new construction. Though no longer commercially used, the process was of enormous industrial importance at the time. Bessemer was knighted in 1879 for his contribution to science and elected a fellow of the Royal Society. He also held at least 129 patents, including a forerunner of continuous casting. His success was somewhat exceptional, as he developed his process from idea to practical reality in his own lifetime and profited as a businessman.

Did You Know?

• Bessemer made his first fortune by reverse-engineering and improving a steam-powered process for making bronze powder used in gold paint, reducing the price from £5 12 shillings per pound to about 4 shillings per pound.
• He patented a method for making a continuous ribbon of plate glass in 1848, but it was not commercially successful.
• After suffering from seasickness in 1868, he designed the SS Bessemer, a passenger steamship with a cabin on gimbals to stay level, but it never made a commercial maiden voyage; the damage to the Calais pier occurred dur
• Bessemer paid Robert Forester Mushet an annual pension of £300 for over 20 years after Mushet's daughter confronted him about her father's contributions.