'Industrial Workshop (a steel works)', 1910.
© Science Museum / Science & Society Picture Library
Oil painting on canvas by A H Knighton Hammond, showing men working in a large steelworks. Steel is an alloy of iron and carbon in which the maximum carbon to iron content is 2%. The addition of a tiny amount of carbon results in a substance that exhibits great strength and hardnes. The low cost of manufacturing steel makes it the most widely used of structural materials.