Editing Industrial Revolution (section)

===Iron industry===
[[File:Reverberatory furnace diagram.png|thumb|The [[reverberatory furnace]] could produce [[cast iron]] using mined coal; the burning [[coal]] is separated from the iron to prevent constituents of the coal, such as sulfur and silica, from becoming impurities in the iron. Iron production increased due to the ability to use mined coal directly.]]
[[File:Ironbridge 6.jpg|thumb|[[The Iron Bridge]] in [[Shropshire]], England, the world's first bridge constructed of iron, opened in 1781.<ref name="Iron bridge">{{cite web|title=Ironbridge Gorge|url=https://whc.unesco.org/en/list/371|website=UNESCO World Heritage Centre|publisher=UNESCO|access-date=20 December 2017}}</ref>]]

====British iron production====
Bar iron was the commodity form of iron used as the raw material for making hardware goods such as nails, wire, hinges, horseshoes, wagon tires, chains, as well as structural shapes. A small amount of bar iron was converted into steel. Cast iron was used for pots, stoves, and other items where its brittleness was tolerable. Most cast iron was refined and converted to bar iron, with substantial losses. Bar iron was made by the [[bloomery]] process, the predominant iron smelting process until the late 18th century.

In the UK in 1720, there were 20,500 tons of [[charcoal iron]] and 400 tons with coke. In 1806, charcoal iron production had dropped to 7,800 tons and coke cast iron was 250,000 tons.<ref name="Tylecote_1992"/>{{rp|125}} In 1750, the UK imported 31,000 tons of bar iron and either refined from cast iron or directly produced 18,800 tons of bar iron, using charcoal and 100 tons using coke. In 1796, the UK was making 125,000 tons of bar iron with coke and 6,400 tons with charcoal; imports were 38,000 tons and exports were 24,600 tons. In 1806 the UK did not import bar iron but exported 31,500 tons.<ref name="Tylecote_1992"/>{{rp|125}}

====Iron process innovations====
[[File:Puddling furnace int captions.png|thumb|Horizontal (lower) and vertical (upper) cross-sections of a single [[Puddling (metallurgy)|puddling]] furnace]]
A major change in the iron industries during the Industrial Revolution was the replacement of wood and other bio-fuels with [[coal]]; for a given amount of heat, [[Coal mining|mining coal]] required much less labour than cutting wood and converting it to [[charcoal]],<ref>{{cite book
|title= American Iron 1607–1900|last=Gordon|first= Robert B|year=1996 |publisher = Johns Hopkins University Press|location=Baltimore and London|isbn= 978-0-8018-6816-0 |page=156}}</ref> and coal was more abundant than wood, supplies of which were becoming scarce before the enormous increase in iron production that took place in the late 18th century.<ref name="David S. Landes 1969"/><ref name="Tylecote_1992">{{cite book|title=A History of Metallurgy, Second Edition |last=Tylecote |first=R. F.|year= 1992|publisher =Maney Publishing, for the Institute of Materials |location= London|isbn=978-0-901462-88-6}}</ref>{{rp|122}}

In 1709, [[Abraham Darby I|Abraham Darby]] made progress using coke to fuel his blast furnaces at [[Coalbrookdale]].<ref>{{cite news |title=Danny Boyle's intro on Olympics programme |url=http://www.awardsdaily.com/blog/2012/07/27/danny-boyles-intro-on-olympics-programme/ |publisher=Awards Daily |first=Ryan |last=Adams |date=27 July 2012 |access-date=20 December 2017 |archive-date=6 February 2013 |archive-url=https://web.archive.org/web/20130206135250/http://www.awardsdaily.com/blog/2012/07/27/danny-boyles-intro-on-olympics-programme/ |url-status=live }}</ref> However, the coke pig iron made was not suitable for making wrought iron and was used mostly for the production of cast iron goods, such as pots and kettles. He had the advantage over his rivals in that his pots, cast by his patented process, were thinner and cheaper.

In 1750, [[coke (fuel)|coke]] had generally replaced charcoal in the smelting of copper and lead and was in widespread use in glass production. In the smelting and refining of iron, coal and coke produced inferior iron to that made with charcoal because of the coal's sulfur content. Low sulfur coals were known, but they still contained harmful amounts.<ref name="Tylecote_1992"/>{{rp|122–125}} Another factor limiting the iron industry before the Industrial Revolution was the scarcity of water power to power blast bellows. This limitation was overcome by the steam engine.<ref name="Tylecote_1992" />

Use of coal in iron smelting started before the Industrial Revolution, based on innovations by [[Clement Clerke]] and others from 1678, using coal [[reverberatory furnace]]s known as cupolas. These were operated by the flames playing on the ore and charcoal or coke mixture, [[Redox|reducing]] the [[oxide]] to metal. This has the advantage that impurities in the coal do not migrate into the metal. This technology was applied to lead from 1678 and copper from 1687. It was applied to iron foundry work in the 1690s, but in this case the reverberatory furnace was known as an air furnace.<ref>{{Cite book |last=Tylecote |first=R. F. |url=https://books.google.com/books?id=H5hTAAAAMAAJ&q=This+technology+was+applied+to+lead+from+1678+and+to+copper+from+1687.+It+was+also+applied+to+iron+foundry+work+in+the+1690s,+but+in+this+case+the+reverberatory+furnace+was+known+as+an+air+furnace.+(The+foundry+cupola+is+a+different,+and+later,+innovation.) |title=A History of Metallurgy |date=1976 |publisher=Metals Society |isbn=978-0-904357-06-6 |language=en |access-date=28 November 2022 |archive-date=4 April 2023 |archive-url=https://web.archive.org/web/20230404131200/https://books.google.com/books?id=H5hTAAAAMAAJ&q=This+technology+was+applied+to+lead+from+1678+and+to+copper+from+1687.+It+was+also+applied+to+iron+foundry+work+in+the+1690s,+but+in+this+case+the+reverberatory+furnace+was+known+as+an+air+furnace.+(The+foundry+cupola+is+a+different,+and+later,+innovation.) |url-status=live }}</ref>

Coke pig iron was hardly used to produce wrought iron until 1755, when Darby's son [[Abraham Darby II]] built furnaces at [[Horsehay]] and [[Ketley]] where low sulfur coal was available, and not far from Coalbrookdale. These furnaces were equipped with water-powered bellows, the water being pumped by [[Newcomen atmospheric engine]]s. [[Abraham Darby III]] installed similar steam-pumped, water-powered blowing cylinders at the Dale Company when he took control in 1768. The Dale Company used Newcomen engines to drain its mines and made parts for engines which it sold throughout the country.<ref name="Tylecote_1992" />{{rp|123–125}}

Steam engines made the use of higher-pressure and volume blast practical; however, the leather used in bellows was expensive to replace. In 1757, ironmaster [[John Wilkinson (industrialist)|John Wilkinson]] patented a hydraulic powered [[blowing engine]] for blast furnaces.<ref name="Temple 1986">{{cite book|title=The Genius of China: 3000 years of science, discovery and invention|url=https://archive.org/details/geniusofchina3000temp|url-access=limited|last1=Temple|first1= Robert|first2=Joseph|last2=Needham|year= 1986|publisher = Simon and Schuster|location=New York|pages=[https://archive.org/details/geniusofchina3000temp/page/65 65]|isbn=978-0-671-62028-8}} Based on the works of Joseph Needham</ref> The blowing cylinder for blast furnaces was introduced in 1760 and the first blowing cylinder made of cast iron is believed to be the one used at Carrington in 1768, designed by [[John Smeaton]].<ref name="Tylecote_1992"/>{{rp|124, 135}}

Cast iron cylinders for use with a piston were difficult to manufacture. [[James Watt]] had difficulty trying to have a cylinder made for his first steam engine. In 1774 Wilkinson invented a machine for boring cylinders. After Wilkinson bored the first successful cylinder for a [[Boulton and Watt]] steam engine in 1776, he was given an exclusive contract for providing cylinders.<ref name="Roe1916"/><ref>Author Simon Winchester dates the start of the Industrial Revolution to 4 May 1776, the day that John Wilkinson presented James Watt with his precision-made cylinder. (19 August 2018) [https://transcripts.cnn.com/show/fzgps/date/2018-08-19/segment/01 Fareed Zakaria ] . CNN.com</ref> Watt developed a rotary steam engine in 1782, they were widely applied to blowing, hammering, rolling and slitting.<ref name="Tylecote_1992"/>{{rp|124}}

In addition to lower cost and greater availability, coke had other advantages over charcoal in that it was harder and made the column of materials flowing down the blast furnace more porous and did not crush in the much taller furnaces of the late 19th century.<ref>{{cite book|title=Inside the Black Box: Technology and Economics|last=Rosenberg|first=Nathan|year=1982|publisher=Cambridge University Press|location=Cambridge; New York|isbn=978-0-521-27367-1|page=[https://archive.org/details/insideblackboxte00rose/page/85 85]|url=https://archive.org/details/insideblackboxte00rose/page/85}}</ref><ref name="auto3">{{cite book|title=The Unbound Prometheus: Technological Change and Industrial Development in Western Europe from 1750 to the Present |last=Landes |first= David. S.|year= 1969|publisher =Press Syndicate of the University of Cambridge|location= Cambridge; New York|isbn=978-0-521-09418-4}}</ref>

As cast iron became cheaper and widely available, it began being a structural material for bridges and buildings. A famous early example is [[The Iron Bridge]] built in 1778 with cast iron produced by Abraham Darby III.<ref name="Iron bridge"/> However, most cast iron was converted to wrought iron. Conversion of cast iron had long been done in a [[finery forge]]. An improved refining process known as [[potting and stamping]] was developed, but this was superseded by [[Henry Cort]]'s [[Puddling (metallurgy)|puddling]] process. Cort developed significant iron manufacturing processes: [[Rolling (metalworking)|rolling]] in 1783 and puddling in 1784.<ref name="David S. Landes 1969" />{{rp|91}} Puddling produced a structural grade iron at a relatively low cost.
Puddling was backbreaking and extremely hot work. Few puddlers lived to be 40.<ref name="David S. Landes 1969"/>{{rp|218}} Puddling became widely used after 1800. British iron manufacturers had used considerable amounts of iron imported from Sweden and Russia to supplement domestic supplies. Because of the increased British production, by the 1790s Britain eliminated imports and became a net exporter of bar iron.

[[Hot blast]], patented by the Scottish inventor [[James Beaumont Neilson]] in 1828, was the most important development of the 19th century for saving energy in making pig iron. The amount of fuel to make a unit of pig iron was reduced at first by between one-third using coke or two-thirds using coal;<ref>{{cite book|first= David S.|last= Landes|date=1969|title= The Unbound Prometheus|publisher= Press Syndicate of the University of Cambridge|isbn= 978-0-521-09418-4|page=92}}</ref> the efficiency gains continued as the technology improved.<ref>{{Harvnb|Ayres|1989|p=21}}</ref> Hot blast raised the operating temperature of furnaces, increasing their capacity. Using less coal or coke meant introducing fewer impurities into the pig iron. This meant that lower quality coal could be used in areas where [[Metallurgical coal|coking coal]] was unavailable or too expensive;<ref>{{cite book |title= Inside the Black Box: Technology and Economics |last= Rosenberg |first= Nathan |year= 1982 |publisher= Cambridge University Press |location= Cambridge; New York |isbn= 978-0-521-27367-1 |page= [https://archive.org/details/insideblackboxte00rose/page/90 90] |url= https://archive.org/details/insideblackboxte00rose/page/90 }}</ref> however, by the end of the 19th century transportation costs fell considerably.

Shortly before the Industrial Revolution, an improvement was made in the production of [[steel]], which was an expensive commodity and used only where iron would not do, such as for cutting edge tools and springs. [[Benjamin Huntsman]] developed his [[crucible steel]] technique in the 1740s.<ref>{{Cite web |title=Steel Production {{!}} History of Western Civilization II |url=https://courses.lumenlearning.com/suny-hccc-worldhistory2/chapter/steel-production/ |access-date=1 May 2022 |website=courses.lumenlearning.com |archive-date=11 May 2022 |archive-url=https://web.archive.org/web/20220511213833/https://courses.lumenlearning.com/suny-hccc-worldhistory2/chapter/steel-production/ |url-status=live }}</ref> The supply of cheaper iron and steel aided a number of industries, such as those making nails, hinges, wire, and other hardware items. The development of machine tools allowed better working of iron, causing it to be increasingly used in the rapidly growing machinery and engine industries.<ref>{{Cite web|url=https://courses.lumenlearning.com/boundless-worldhistory/chapter/iron-making/|title=Iron Making {{!}} Boundless World History|website=courses.lumenlearning.com|access-date=9 January 2020|archive-date=13 April 2021|archive-url=https://web.archive.org/web/20210413171318/https://courses.lumenlearning.com/boundless-worldhistory/chapter/iron-making/|url-status=live}}</ref>