Coal and iron ore were essential for the. manufacture of machines were plenty in England. Materials like black lead, copper and white lead which were extensively used in industries were also plenty in the country. But until the 18th century, there was a shortage of “usable iron”. Iron was made by melting iron ore into a liquid state and then separating the pure iron from it. To melt iron ore charcoal was used. There were many problems with this. Since charcoal was brittle, it was difficult to transport charcoal to faraway places. Because of the impurities in it, the iron produced this way was not of high quality. Moreover charcoal could not produce high heat. Because of the large scale deforestation, there was a shortage of charcoal.
The solution to this problem was found by the Darby family of Shropshire. In 50 years, three generations of this family (grandfather, father, and son) brought a revolution in the rening of iron.
In 1709, Abraham Darby (1677-1717) developed the first blast furnace which could maintain a very high degree of heat. In it, coke could be used. Coke was made by removing the sulphur and other impurities from coal. With this, there was no need for charcoal. The iron that was made from the blast furnace of Darby was strong and of a higher quality.
Darby II(1711-1768) made cast iron from iron. This would not break easily. Henry Court (1740-1823) made two important discoveries – the puddling furnace to remove impurities from pig iron and the rolling mill to produce rails. These discoveries helped in producing many different kinds of iron products.
