<P> Innovation in 18th - century Birmingham often took the form of incremental series of small - scale improvements to existing products or processes, but also included major developments that lay at the heart of the emergence of industrial society . In 1709 the Birmingham - trained Abraham Darby I moved to Coalbrookdale in Shropshire and built the first blast furnace to successfully smelt iron ore with coke, transforming the quality, volume and scale on which it was possible to produce cast iron . In 1732 Lewis Paul and John Wyatt invented roller spinning, the "one novel idea of the first importance" in the development of the mechanised cotton industry . In 1741 they opened the world's first cotton mill in Birmingham's Upper Priory . In 1746 John Roebuck invented the lead chamber process, enabling the large - scale manufacture of sulphuric acid, and in 1780 James Keir developed a process for the bulk manufacture of alkali, together marking the birth of the modern chemical industry . In 1765 Matthew Boulton opened the Soho Manufactory, pioneering the combination and mechanisation under one roof of previously separate manufacturing activities through a system known as "rational manufacture". As the largest manufacturing unit in Europe this come to symbolise the emergence of the factory system . </P> <P> Most significant, however, was the development in 1776 of the industrial steam engine by James Watt and Matthew Boulton . Freeing for the first time the manufacturing capacity of human society from the limited availability of hand, water and animal power, this was arguably the pivotal moment of the entire industrial revolution and a key factor in the worldwide increases in productivity that would follow over the following century . </P> <P> Birmingham rose to national political prominence in the campaign for political reform in the early 19th century, with Thomas Attwood and the Birmingham Political Union bringing the country to the brink of civil war during the Days of May that preceded the passing of the Great Reform Act in 1832 . The Union's meetings on Newhall Hill in 1831 and 1832 were the largest political assemblies Britain had ever seen . Lord Durham, who drafted the Act, wrote that "the country owed Reform to Birmingham, and its salvation from revolution". This reputation for having "shaken the fabric of privilege to its base" in 1832 led John Bright to make Birmingham the platform for his successful campaign for the Second Reform Act of 1867, which extended voting rights to the urban working class . </P> <P> Birmingham's tradition of innovation continued into the 19th century . Birmingham was the terminus for both of the world's first two long - distance railway lines: the 82 mile Grand Junction Railway of 1837 and the 112 mile London and Birmingham Railway of 1838 . Birmingham schoolteacher Rowland Hill invented the postage stamp and created the first modern universal postal system in 1839 . Alexander Parkes invented the first man - made plastic in the Jewellery Quarter in 1855 . </P>

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