For the first time for several decades, there are grounds for optimism about the future of Sheffield’s steel industry (very much reduced in scale though it now is). Sheffield Forgemasters (now UK state owned) is building a major new facility, and Special Melted Products (with an infusion of Taiwanese capital) is also expanding. This isn’t about the standard grades of steel for use in construction – the expansion is to meet demand for specialised forgings from speciality steels and other alloys, driven by applications in defense, aerospace, civil nuclear and energy, and influenced by a new focus on UK national resilience and industrial capacity. This gives me a pretext to republish this piece I wrote nearly ten years ago about the history of the steel industry in Sheffield – and the valuable lessons this history can teach us about innovation.
As someone interested in the history of innovation, I take great pleasure in seeing the many tangible reminders of the industrial revolution that are to be found where I live and work, in North Derbyshire and Sheffield. I get the impression that academics are sometimes a little snooty about local history, seeing it as the domain of amateurs and enthusiasts. If so, this would be a pity, because a deeper understanding of the histories of particular places could be helpful in providing some tests of, and illustrations for, the grand theories that are the currency of academics. I’ve recently read the late David Hey’s excellent “History of Sheffield”, and this prompted these reflections on what we can learn about the history of innovation from the example of this city, which became so famous for its steel industries. What can we learn from the rise (and fall) of steel in Sheffield?
Specialisation
“Ther was no man, for peril, dorste hym touche.
A Sheffeld thwitel baar he in his hose.”
The Reeves Tale, Canterbury Tales, Chaucer.
When the Londoner Geoffrey Chaucer wrote these words, in the late 14th century, the reputation of Sheffield as a place that knives came from (Thwitel = whittle: a knife) was already established. As early as 1379, 25% of the population of Sheffield were listed as metal-workers. This was a degree of focus that was early, and well developed, but not completely exceptional – the development of medieval urban economies in response to widening patterns of trade was already leading to specialisation based on the particular advantages location or natural resources gave them[1]. Towns like Halifax and Salisbury (and many others) were developing clusters in textiles, while other towns found narrower niches, like Burton-on-Trent’s twin trades of religious statuary and beer. Burton’s seemingly odd combination arose from the local deposits of gypsum [2]; what was behind Sheffield’s choice of blades?
I don’t think the answer to this question is at all obvious. Sheffield has deposits of ironstone, but that’s very common across England, so the early presence of iron smelting isn’t a great selective advantage. It has abundant water power, but again it is far from unique in this. What one can say is that knives are an obvious product for somewhere to specialise in at the developing stages of an economy. They are relatively small and portable, and thus relatively transported by packhorse or bagman from a place like Sheffield, which is distant from easy water transport. They have a very large market – everyone wants a knife, and Sheffield’s products were at the affordable end of the market. And making them clearly takes some degree of craft skill and some capital investment. So perhaps there isn’t much more to say that many places could have ended up as centres of knife making, but chance and contingency pointed to Sheffield.
But once a specialisation becomes established, the advantages are clear. Skills are passed from person to person, often down families. There is a degree of shared infrastructure – water mills owned by the land-owners drove grinding wheels and operated bellows and trip-hammers. What we’d call a supply chain developed, with raw materials being brought in, and networks to distribute the products across the country would form. And finally, as the Chaucer quote indicates, “Sheffield” soon became an identifiable nationwide brand, recognisable as the origin of choice for the concealed weapon of a bullying and violent miller.
Mobilisation of energy resources
Three sources of energy were important for the early cutlery industry in Sheffield and its near hinterland (traditionally known as Hallamshire) – water power, wood and coal. The river Don and its tributaries run fast off the steep flanks of the moors to the west of the city, fed by the ample Pennine rain. By the twelfth century, water mills were becoming widely used for industrial purposes across England. The introduction of water-powered trip-hammers mechanised the repetitive beating that was required to work iron, and the blades were sharpened and polished on water-powered grinding wheels. By 1637 400-500 workman were using these wheels. The steep, wooded hillsides rising from these rivers were ideal for the production of coppiced wood for conversion into charcoal, used for the production of iron and to heat the forges.
But Sheffield also lies on a coal-field, and outcroppings of the coal-seams would have been obvious in the sides of the gorges that the streams flowed through. These seams would have been easily followed and worked from surface pits. We know that coal-mining was already being conducted in a serious way at the time Chaucer was writing. A lease for a coal mine survives from 1398, specifying a rent to the land-owner of 20 marks a year [3]. The lease specifies the scale of the mine, which employed 4 underground workers, and was deep and extensive enough to require drainage by a sough. By 1540 John Leland could comment “Hallamshire hath plenti of woodde, and yet ther is burnid much se cole”. What was this “sea-coal” (so called to distinguish it from char-coal) being used for?
One thing we can be sure of is that it was not being mined for sale outside the region. Transport from Sheffield for bulk commodities was very difficult – the moors to the west would have been passable only on foot or by pack-horse, while the nearest navigable waterway was twenty difficult miles to the east, at Bawtrey wharf. Sheffield coal couldn’t compete on national markets with coal from Newcastle, which was mined on the banks of the Tyne and Wear, from which it could be loaded straight onto ships for export to London and elsewhere. Instead, Sheffield coal was for local use – as a substitute for charcoal, for heating forges and furnaces.
By 1672 Sheffield city had 224 metal-working smithies in the town itself, and another 376 in its Hallamshire hinterland. This scale of expansion was only made possible by the large-scale availability and use of coal as a substitute for charcoal. By this time all available woods were intensively coppiced, for white-coal (kiln-dried wood) and charcoal. White-coal and charcoal needed to be reserved for the more sensitive metallurgical operations that its sulphur content makes coal unsuitable for (smelting the lead from the nearby Derbyshire ore fields, in the case of white coal, and for the smelting iron and converting iron to steel for charcoal). These constraints on the use of coal as a substitute for charcoal were relaxed by the development of the coking process. Although the use of coke in iron-making is associated with Abraham Darby in Coalbrookedale in the early 18th century, its first large scale industrial use in England was recorded in 1640 in nearby Derby, for the drying of malt for beer. Certainly by the early 18th century coke was being extensively used in Sheffield in smiths’ hearths.
Meanwhile water power continued to grow in importance with the expansion of the industry; by 1660 at least 49 sites on the Don and its tributaries had been dammed for industrial purposes, with two thirds of these used for grinding wheels. By 1794 all sites for water wheels were occupied, & steam engines were being installed alongside the watermills to increase capacity, marking the point at which coal became the primary energy source for almost all aspects of the industry (some charcoal was still needed in the cementation process of making steel).
New technologies, new markets, new products
It wasn’t until the 18th century that Sheffield produced a radical innovation that had a significant impact on its industry; before that cutlers undoubtedly produced incremental improvements to their products and processes, and new techniques and technologies were adopted from elsewhere. One shouldn’t make the mistake of thinking that technological innovation only began in the 18th century in general, though, despite the impression one might get from reading some economists.
To go back to the beginning, using the methods of iron making developed in the Iron Age, experimental archaeology suggests that to produce a single kilogram of smithed bar iron would take 25 person days of work and 100 kg of charcoal [4]. By the fifteenth century, in the Weald, at the time the most advanced iron making region of England, a bloomery might produce about 14 kg of iron a day, using 110 kg of charcoal and the labour of 4 workers (mostly to operate the bellows) [5]. On top of this nearly 90-fold increase in productivity, the use of water-power increased productivity by another factor of 6. Another jump in productivity came with the introduction of blast furnaces from the continent in 1491 – early blast furnaces would produce 6 or 7 tonnes of iron in a 6 day run (though the much higher carbon content of pig iron compared to bloomery iron required further processing to convert it into wrought iron, done in a finery forge with charcoal heating and a water-powered trip-hammer).
This is a perhaps a digression in the industrial history of Sheffield, though. Sheffield was an iron-making region, though it wasn’t in the forefront even of the British industry. The cutlers of Sheffield had no hesitation in buying in better quality bar-iron from Spain and the Baltic to make their products. More relevant to the cutlery trade was the cementation process to convert bar-iron to steel in large batches. This had been invented in Germany in the 1580’s, introduced to Coalbrookdale in 1615, and reached Sheffield in 1709. The key point is that before the 18th century, Sheffield was an adopter of technology, not a creator (and for that matter, most of these techniques would have been familiar in China almost a millennium earlier).
This changed with the invention of crucible steel by Benjamin Huntsman, which provided the first way of producing steel of consistent quality at scale, by melting it in coke-fuelled furnaces. There are three things about Huntsman that are worth noting here. Firstly, his background – he was not a cutler or iron-master, he was a clockmaker. His motivation, then, was frustration at the shortcomings of the existing materials for fine work such as making springs. Secondly, he wasn’t from Sheffield. He moved from Doncaster to Sheffield in 1742, specifically to take advantage of Sheffield’s specialisation in steel and products made from it. Finally, it’s worth noting that having perfected his process and established a factory to make crucible steel in 1751, the local cutlers were not willing to use his material, as it wasn’t compatible with existing manufacturing processes.
Huntsman managed to keep his process secret for a decade or so, during which his material found success. It was exported to manufacturers elsewhere in England and abroad, it was used by the Sheffield cutlers, when they eventually adapted to the new material, and it provided the driving force for an expanding Sheffield tool-making industry. Crucible steel wasn’t the only innovation in materials at the time; in 1743 Thomas Boulsover invented a method for fusing a coating of silver onto a body of copper, to make what became known as “old Sheffield plate”. This allowed the development of a large market in lower cost flatware [6] and hollow-ware – silver plated forks and spoons, candlesticks, snuff-boxes, coffee pots and so on – to fulfil the rising demand for affordable luxuries from an expanding middle class.
The development of a new Atlantic empire also provided new markets – the slave plantations of the Caribbean and the Americas were equipped with plantation knives and machetes made in Sheffield. After independence, the USA continued to be a major market, many Sheffield companies had agents there, and new products were designed in response to its demands. One colourful example from the 1830’s was the Bowie knife – an icon of the old West, but largely made in England. Bowie knives were a centre-piece of the catalogues that were produced for the American market, and best-sellers right up to the time when they began to be superseded by handguns as the preferred artefact for interpersonal violence, from the 1850’s onward. Even as the capacity of the USA’s own industry grew, much of the tool steel for their machine shops came from Sheffield, with as much as one third of Sheffield’s steel output being exported across the Atlantic in the first half of the 19th century.
The “second industrial revolution” – state power and the invention of R&D
Industrialisation in England and the development of the USA between them fuelled a substantial expansion of the Sheffield steel industry in the first half of the 19th century. But it was another technological innovation that transformed steel from being a material for making small, high value artefacts to building the infrastructure of the modern world – in railways, bridges, ships and sky-scrapers. In 1856, Henry Bessemer announced the invention of a new way of converting pig iron into steel. The Bessemer converter converted 25 tonnes of iron into steel in half an hour; it reduced the price of steel by a factor of five and greatly increased the volumes produced. Like Huntsman before him, Bessemer moved to Sheffield to build a factory to implement his invention. Unlike Huntsman, he encouraged other manufacturers to build Bessemer converters of their own, under license.
The railway booms in England and the USA provided massive markets for the new mass-produced steel, but Sheffield’s first-mover advantage didn’t last long. Within a decade or two, competition from other parts of the UK and from a rapidly developing US steel industry, together with a slowing of the railway boom, made life harder for the new, industrial scale Sheffield steel makers. They chose to respond by moving up-market, making innovative, higher quality alloy steels, for higher value markets.
In this they were helped by three factors. Firstly, a new process for making steel – the Siemens open hearth process, developed in South Wales by 1870, was rapidly adopted in Sheffield. This was slower than the Bessemer process to make steel – it took 10-12 hours to convert a 100 tonne batch. But the quality of the steel was higher, and significantly it was possible to analyse the material as it was being converted, to do in-line quality control. Secondly, an important new market had appeared. The late nineteenth century saw a naval arms race between Britain and Germany, with bigger, more heavily armed ships being built, and more powerful guns and armour-piercing shells being made in response. Sheffield firms dominated these new, government driven markets for armour plate and guns, which accounted for much of the expansion of the industry in the second half of the nineteenth century.
The third factor was the development of a scientific understanding of the metallurgy of steel. It’s fair to say that until the mid-nineteenth century, innovation in steel had been pretty much entirely empirical. It was a Sheffield scientist who changed this. Henry Sorby was the son of a wealthy Sheffield family, and he used his private income to support a career as a gentleman scientist. He made distinguished contributions to geology and natural history, for which he was elected to the Royal Society, but his biggest contribution – both to Sheffield and science more widely – was the invention of the techniques of metallographic microscopy, in 1863.
Formal institutions in support of science-led innovation were slow to arrive in Sheffield. Traditionally, the industry was regulated by the Company of Cutlers in Hallamshire – a guild incorporated in 1624, whose traditional purpose was to control entry to the trade by apprenticeship. It’s fair to say that the Cutlers’ Company is a guardian of standards and protector and advocate of the Sheffield brand, rather than a promoter of innovation [7]. A Mechanics Institute was set up in 1832, though the motivation for this seems to have been as a response to the political unrest of the time as much as a desire for improvement through education. It wasn’t until the late nineteenth century that technical education was pursued seriously, through the foundation of Firth College in 1879, and Sheffield Technical School in 1884. It was these institutions, promoted both by Henry Sorby and a local steelmaker, Mark Firth, that in 1905 came together with the medical school to form the University of Sheffield, which from the outset had a strongly technical character [8].
The key innovations, however, took place in industry. In 1882, Robert Hadfield invented Manganese steel, an alloy which maintains its toughness on hardening, has very high impact strength and great resistance to wear. Another steel alloy invented in Sheffield achieved even greater prominence: stainless steel. Harry Brearley discovered this chromium alloy of steel in 1912, while looking for a material able to resist the hot and corrosive environment found inside the barrels of rifles and naval guns. The applications in Sheffield’s traditional, and still important, cutlery industry were very quickly realised. Brearley’s discovery was refined by William Hatfield, who developed the mostly widely used modern grade of stainless steel, 18/8.
It’s worth stepping back from these individual inventions to consider the institutional framework in which they were made. Robert Hadfield was, like Sorby, the gifted son of a local manufacturer. Having decided to stay in the steel industry rather than going to University, his father encouraged him to set up a laboratory. When his father died, he took over the business, but continued, in effect, both to lead its research and development activities and to contribute personally as a scientist, as well as running the company. He collaborated extensively with academic scientists throughout Europe, and was elected to the Royal Society in 1909. Harry Brearley, on the other hand, was an employee – a steel-worker’s son who left school at 14 to become a labourer, and became a bottle-washer in the chemical laboratory in Thomas Firth’s steel-works. From there, he was able to learn enough science at evening classes to rise to a leadership position in a new R&D laboratory jointly supported by two Sheffield steel companies, Firth and Brown. After his discovery of stainless steel he left the Brown-Firth laboratories with some bitterness about the patent rights, and his place was taken by William Hatfield, who had a doctorate in metallurgy (presumably one of the first) from the newly chartered University of Sheffield [10].
Between 1880 and 1918, then, industrial research and development had become institutionalised in the Sheffield steel industry. It was personally supported by the leading capitalists in the industry, institutions were in place to supply skilled scientists and technicians, and its activities were integrated into wider national and international scientific networks.
What was the cause of Sheffield’s steel pre-eminence?
The few years between the end of the first world war and the economic troubles of the 1930’s were probably the high water mark for steel in Sheffield – in the area of high performance alloy steels, its major rivals in Germany were engulfed in the chaos after the war, which itself had provided a massive and lucrative market for Sheffield’s steel industry. Its tools and cutlery industries had buoyant worldwide markets, helped by favourable treatment in Britain’s expansive overseas empire and dominions. What was the cause that led a small, provincial town to such world dominance of a major industrial sector?
Of course, there was no single cause – there were many causes, operating differently at different points in the city’s history, often reinforcing each other, usually amplifying the effects of chance and contingency. In this narrative, I’ve discussed all these as contributory factors at various times:
The point goes beyond the fact that there were multiple causes, it is that these different causes were often mutually reinforcing. For example, the availability of water power contributed to the specialisation of the area in edged tools, but it was the early exploitation of coal that permitted a concentration of industry that hugely exceeded the constraints that the availability of wood and water power would otherwise have imposed. It was this concentration that drove a contagious culture of innovation, and then these innovations (e.g. Old Sheffield Plate, Huntsman’s crucible steel) in turn drove demand for yet more energy, met by the locally mined coal. It seems to me that it is understanding this process of interaction and mutual reinforcement of multiple causal factors that is essential for understanding the industrialisation of Britain.
[1] See Dyer, Making a Living in the Middle Ages –
[2] Gypsum is calcium sulphate, which in the form of alabaster makes a soft, white, easily worked rock ideal for mass production of statues. Its presence in ground-water makes it particularly suitable for making bright, clear beers which store and travel well (I know that in this time of craft beer I’m in the dwindling minority of consumers who, rather than wanting to be overwhelmed by the crude taste of hops, prefer their beer to taste of sulphur, as is characteristic of the finest, most traditional Burton bitter).
[3] 20 marks is £13 6s 8d. This corresponds to about £9,000 in today’s money correcting for price inflation, about £95,000 relative to average wages.
[4] P. Crew, quoted in Barry Cunliffe’s Iron Age Communities of Britain (“Lovely boy, arrow climber” – yes, that Peter Crew).
[5] The Iron Industry of the Weald, H. Cleere and D. Crossley
[6] In the traditional nomenclature of Sheffield, cutlery refers to tools with an edge – knives, razors, scalpels, scissors, scythes and so on. Forks and spoons, not having sharpened edges, don’t count as cutlery – they’re flat-ware.
[7] The Company of Cutlers in Hallamshire is still going strong, now representing all with an interest in manufacturing in the Sheffield region.
[8] There had been an earlier attempt by the nascent institution to join the federal Victoria University, which in the late 19th century comprised what were to become the Universities of Manchester, Leeds and Liverpool. Sheffield’s application to join was rejected because of its perceived over-emphasis on engineering and other technical subjects, rather than the classics and humanities. In any case, the partnership fell apart in the early 20th century, with Manchester, Liverpool and Leeds all becoming independent institutions.
[9] Inventors in the USA and Germany were working to develop non-rusting steels using very similar approaches, and Brearley’s priority is disputed by some. But, to use a phrase I picked up from a colleague about a more recent discovery, “he may not have invented it first, but he invented it best.”
[10] Here I’ve drawn on information in the Royal Society’s obituary notices for Robert Hadfield and William Hatfield.
Minimum transistor footprint (product of metal pitch and contacted gate pitch) for successive semiconductor process nodes. Data: (1994 – 2014 inclusive) –