William Tulloch Jeans (1848–1907) was a parliamentary journalist with an interest in economics and technology. This book was first published in 1884, and comprises biographies of six men whom Jeans believed to have made significant contributions to the development of modern steel technology. The Bessemer process revolutionised steel-making, reducing the cost and allowing steel to replace the much more brittle iron in civil engineering projects such as bridges. Siemens' regenerative furnace allowed much more fuel-efficient manufacture of steel. Sir Joseph Whitworth developed a method of producing stronger steel by removing blowholes in the ingots. Sir John Brown's rolled steel was used in almost all the British navy's armour-plated ships. The work of Sidney Gilchrist Thomas and George Snelus on reducing phosphorus content in steel meant low-grade ores could be used. The combined researches of these men transformed modern industrial and engineering methods.