Sir Henry Besemer (1813-1898) cast this ingot at a works in Greenwich, London. Besemer learned metallurgy working in his father's foundry. In 1856, in response to demand for stronger cannon able to fire a new type of artillery shell in the Crimean War, he invented the Besemer proces, enabling molten pig-iron to be turned into steel by a blowing air through it in a tilting converter. This was the first proces for producing large amounts of good quality steel cheaply. Previously, steel was available in small quantities produced by either the cementation or crucible proceses. Hence engineers were restricted to using wrought iron, which is relatively strong in tension, or cast iron, which is brittle and weak in tension.
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