how one company transformed England's iron industry

Abraham Darby was born at Wren's Nest, near Dudley, England, in 1678. After serving an apprenticeship in Birmingham with a malt mill maker, he moved to Bristol and set up in business himself. He soon became involved with other Quakers in the city's brass industry, and it was this that set him on the route to his greatest innovation.

Abraham and his partners were manufacturing brass pans for domestic use; the problem was they were very labor intensive to make. Darby's solution was to make cast iron pots using molten metal poured into molds made from sand. He patented the process in 1707, and the following year leased the Coalbrookdale furnace in order to make his own iron.

The process of smelting iron ore to produce cast or pig iron traditionally relied on charcoal to fire the furnaces. This placed a strict limit on the amount of iron that could be produced at any one firing, however, because charcoal broke down quickly under the intense heat necessary for smelting. In addition, the forests of England were being seriously depleted because of the demands of the iron trade for wood to make charcoal. From the beginning of the 17th century there were attempts to substitute coke, a product of coal, for charcoal in the production of pig iron, but the presence of sulphur in coke tended to make the iron too brittle for practical industrial use.

In 1708, when Darby set up the Bristol Iron Company in Coalbrookdale in the Severn Valley, he chose his location carefully. The region was known to have supplies of coal with a relatively low sulphur content, as well as deposits of iron ore close at hand. The use of coke enabled Darby to build taller and hotter blast furnaces than had been possible before, and he soon began to turn out iron of a high quality.

base of the blast furnace used by Abraham Darby to produce his high-quality cast iron

At first Darby's iron was used mainly to cast cooking utensils and iron fittings because the forge owners and blacksmiths regarded charcoal-smelted iron as the only kind suitable for their trade. A breakthrough occurred when Thomas Newcomen came to Darby to have the cylinders cast for his steam engine. The association of the Coalbrookdale factory with steam power continued to the end of the 18th century, when the plant built the first high-pressure boiler for Richard Trevithick.

The Darby family managed to keep its industrial secrets largely within its own sphere for five generations. After the death of Abraham Darby in 1717, management of the company passed to his son-in-law Richard Ford. During his time the company began supplying products to Britain's mining industry, including the first iron wheels for use on primitive wooden railways and cast iron cylinders for steam engines used to pump water from deep mines.

Ford died in 1745, and management of the company passed into the hands of the founder's son, Abraham Darby II. Under his leadership, the smelting of iron with coke was perfected to the point where it was suitable for converting into wrought iron, a form of iron which can be shaped by hammering and rolling. In addition, new ironworks were built and the company took control of mining its own raw materials and transporting them on its own network of horse-drawn railways.

a wrought iron bench crafted at Coalbrookdale

When Abraham Darby II died in 1763, management of the company passed to his son-in-law Richard Reynolds, who operated it until Abraham Darby III reached legal age in 1768. It was while under the leadership of Abraham Darby's grandson that the Bristol Iron Company contributed to yet another technological breakthrough.

In 1779, Abraham Darby III and John Wilkinson built the world's first iron bridge. It spanned the gorge of the Severn River around the corner from Coalbrookdale. The bridge's roadway was supported by an arch of five iron ribs, each of which had been cast in two halves. Although Darby and Wilkinson intended the bridge to be an advertisement for another use of iron it immediately became regarded as a great wonder. The bridge, which was designated an Ancient Monument in 1934, carried traffic well into the 1950's, when the foundations became unsafe; it still draws tourists today.

the Iron Bridge over the Severn River

Abraham Darby III died of scarlet fever in 1789, and management of the company fell to his widow, Rebecca, and two of his sisters, Deborah and Sarah. It was during the period of their control that the company carried out work for Richard Trevithick, building the world's first steam locomotive for him in 1802.

The enterprise of the Darbys in Coalbrookdale made the whole area into what has been called the "cradle of the Industrial Revolution." Intense and more varied manufacturing industries, the building of more furnaces and kilns, the mining of iron ore and coal, and the digging of a network of canals, made it a leading center of industry. In the course of time, however, the mines became worked out and many of the factories moved elsewhere. The canals, forges, and factories fell into disuse, decay, and silence. Alfred Darby II, a great-nephew of Abraham Darby I, was the last of the Darby's to be connected with the Bristol Iron Company, serving as its chairman from 1886 to 1925. With his death the link between the Darby family and the ironworks finally came to an end, after an association of more than 200 years.

Very devout Quakers, neither Abraham Darby nor his heirs allowed their portraits to be painted during their lifetimes.

PRINT SOURCE
Anthony Feldman and Peter Ford Scientists and Inventors, The People Who Made Technology from Earliest Times to Present Day New York: Facts on File, 1979

WEB SOURCE
Ironbridge Gorge Museum www.ironbridge.org.uk

SEE ALSO
Thomas Newcomen

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This page was last updated on September 25, 2017.