Changes

==Later Developments==

White steel was already around soon after iron working developed, it took some time before mastering the technology improved. The Romans mastered using coal, rather than wood, for fuel in furnaces. This gave them a new fuel source to produce better quality iron and steel. However, this practice did not become widespread and may not have been extensively used after the Romans in Europe. New steel production techniques from China and India, which developed by the 5th century CE, did, however, spread to other areas of the Old World. This included mixing wrought and cast iron together to form a stronger weapon/tool. The so-called Bessemer method, which is a modern steel production technique and developed much later, already had a precursor developed in China by the 11th century CE (Figure 2). This included repeated cooling and reforging the steel into a stronger product. Problems of having relatively brittle iron were now effectively being solved. Previously, the quality of the iron ore affected the quality of weapons and tools. Now, new production techniques that enabled carbonized iron to be more easily made, and thus creating steel, allowed more rapid spread of better weapons and tools. In the Medieval Islamic world, blast furnaces were developed by the 10-11th centuries. These allowed more industrial production and better production of iron. A process that utilized integration of carbides, through a crucible smelting process, produced some of the strongest steel in the Medieval world. This was the so-called Damascus steel, produced in Syria, that produced some of the best quality swords and weapons of the Medieval world.<ref>For more on iron technology development in late antiquity and the Medieval period, see: Lavan, Luke, Enrico Zanini, and Alexander Sarantis. 2008. <i>Technology in Transition A.D. 300-650.</i> Leiden: BRILL.</ref>

In the 19th century, improvements in blast furnaces, invented by James Beaumont Neilson from Scotland, enabled much cheaper steel to be made. The Bessemer process was soon developed by the 1850s, by Henry Bessemer, which enabled the production of steel to not only be relatively cheaper, but it allowed it to be done more quickly at an industrial scale. Within a half hour, nearly 25 tons of pig iron could be converted to steel. Other forms of steel developed, such as alloy steels that gave greater flexibility to steel. Stainless steel was developed by the early 20th century.<ref>For more on blast furnaces, see: Mokyr, Joel, ed. 1999. <i>The British Industrial Revolution: An Economic Perspective.</i> 2nd ed. Boulder, CO: Westview Press.</ref>

==Deep Impact of Ferrous Technologies==