Without iron, there could have been no meaningful industrialisation. It was needed everywhere, from the framework of spinning mules to the boilers and cylinders of steam engines, from the railway lines that criss-crossed the country to the metal skeletons of a thousand cotton mills and eventually, the iron ships that carried Britain's manufactured goods around the globe.
So it is impossible to overestimate the importance of the contribution made by Britain's iron-masters, in particular the three generations of the Darby family who took the science of iron manufacture to new levels in the 18th century.
Iron had been made in Britain since Roman times, but in small quantities and using charcoal to smelt the ore. So most early foundries were small, woodland-based enterprises close to sources of wood and ore, such as in the Forest of Dean and the Weald.
The first improvement in technique came with the introduction of the blast furnace, where air was forced into the fire by bellows to increase the temperature.The first record we have of such a furnace comes from the Weald in 1496.
By the beginning of the 18th century, iron manufacture and the blast-furnace technique had spread to several parts of the country and it was into this expanding scene that the Darby dynasty made its entrance.
Abraham Darby I was born near Dudley in Worcestershire about 1678, the son of a Quaker farmer.
As a youngster he was apprenticed to a malt-mill maker but in 1704 he visited Holland. When he returned he brought with him several Dutch brass founders, who helped him establish the Baptist Mills brass foundry in Bristol.
In 1708, however, Abraham turned his attention to iron. He saw it as a cheap substitute for brass in the manufacture of cooking utensils.
He patented the use of sand casting and, after leasing an old iron furnace at Coalbrookdale in Shropshire, he went on to perfect a technique for smelting iron ore by using coke.