"All hail, King Steel," wrote Andrew Carnegie in a 1901 paean to the monarch of metals, praising it for working "wonders upon the earth." A few decades earlier a British inventor named Henry Bessemer had figured out how to make steel in large quantities, and Carnegie and other industry titans were now producing millions of tons of it each year, to be used for the structural framing of bridges and skyscrapers, the tracks of sprawling railway networks, the ribs and plates of steamship hulls, and a multitude of other applications extending from food cans to road signs.