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Mankind discovered how to smelt iron at least 4,000 years ago. The basic process went like this:
- Discover how to make charcoal first
- Find some likely-looking reddish rocks
- Choose a nice day, and a location not too close to valuable property
- Mix the rocks and charcoal together in the middle of a suitable pile of other rocks
- Set fire to it all
- Wait until you notice some spongy-looking glowing stuff
- Beat the hell out of this, being careful not to burn yourself
If you do this, you will be rewarded with a fairly insignificant quantity of wrought iron, plus some slag and a certain amount of clinker. The by-products will come in handy when you discover roads, except that you're not going to produce enough of them to extend your road for more than a few feet.
High-volume steelmaking took a bit longer to get going. In fact the whole story, as we'll see, is a quest for a means of making enough of the stuff. For a few thousand years, wrought iron was great for swords and ploughshares, according to the prevailing mood, but the Industrial Revolution had to be put on the back-burner, so to speak.
By about 1700, most of the iron in the known world was being made in Europe. It was then that somebody noticed that we seemed to be running short of trees.
To be slightly more accurate, there were other parts of the world that were making iron too, only Europe ignored them, so they might have been known about, but only among themselves. Anyone who had iron put up too much of a fight to be suitable trading partners on the then-fashionable European model, so they deserved to be ignored.
Anyway, in treeless Shropshire a man named Abraham Darby started experimenting with iron made with coal. He found that it was an excellent process for making industrial quantities of shrapnel. Then he heard that some brewers were roasting their malt using coke, which got round the problem of tainting it with sulphur. Over a pint that tasted much better than the one he'd had the week before, Abe began to ponder the possibility that the sulphur in coal was spoiling his iron too.
Iron produced from coke was a big success, and the transformation of Coalbrookdale into the cradle of modern industry was spectacular, if a little environmentally irresponsible. To show the world the potential of abundant iron, an iron bridge was built at Ironbridge, a particularly apt choice of location.
Very soon, England's green and pleasant land was dotted with dark satanic mills, and proto-economists gave their permission for the Industrial Revolution to get started. Nothing too ambitious yet, mind. A volume process for refining blast furnace iron was needed, because beating the hell out of this much cast iron was proving a bit tiring.
Enter Henry Cort, who was probably from Northamptonshire1. Henry developed a secondary ironmaking process called puddling. Puddling looks ridiculous to the layman; basically you get carbon and slag in your iron when you reduce the ore with Darby's coke, and now you have to get most of this unwanted stuff out again. This is a subtle idea which is quite lost on non-metallurgists. Since being a non-metallurgist is an honourable estate, it suffices to say that puddling involved a kind of conscientious poking rather than swinging big hammers. As a result, it Cort on famously2.
Next came a Doncaster clock-maker called Benjamin Huntsman. It's a bit of a pity that it took a group of statues in a shopping mall near to his adopted home of Sheffield before anyone realised who he was. But even if the man himself was somewhat anonymous, Huntsman's legacy was noticed alright. He developed the crucible process for making steel, and it stood Sheffield in good stead for a couple of centuries, as those big bronze buggers at Meadowhall will testify.
And, for the first time, this was steel, with the non-ferrous bits in solution, and not strung out through the stuff like some kind of heavy-duty Shredded Wheat. The Little Mesters began to learn some subtle smelting and alloying techniques, and the deliberate targeting of a spectrum of properties from high strength to high workability became possible.
Designer Steel had been born. Unfortunately it was more Gucci than Ralph Lauren: seriously expensive and scarce. There was still no volume process for the really good stuff. Clock springs had been added to the swords and ploughshares, but the discerning entrepreneur of the early 19th Century was already looking for boiler-plate and battleships, and it was frankly a bit of a struggle to keep him supplied.
The next and greatest name deserves a lot more credit than the world gives him. You can forget the theory that the railways and steam power were the foundations of the Industrial Revolution proper. Without the Ironmasters, there simply weren't going to be any steam engines or tracks. Until this man came along, the whole enterprise was limping along on the scale of the aforementioned short-range road-building program.
Archimedes knew that the world could be moved with a long-enough lever. The trouble was, who's going to get you the lever? Henry Bessemer's yer man.
Before we get dewy-eyed about this Titan among Titans, it's worth pointing out that this next breakthrough, as well as the next couple, happened in Sheffield too. Just you load of southern jessies remember this next time you sneer at our suitability to host the World Athletic Championships. Or snigger at our football teams. Steel is the fabric of modern civilisation, and the majority of its technology originated in Sheffield. Had the discoveries made in Sheffield never taken place, it would almost certainly write off a good couple of years of your life expectancy.
Bessemer's convertor could turn tons of iron into steel in minutes. He called its product malleable iron, but this time it really was volume steel. Steel. What a word. Speak it only with awe.
The Modern World was suddenly possible, and innovation flourished as the markets boomed. Hadfield introduced manganese, and construction steels were born. Brearley alloyed it with chrome and nickel, and created stainless steel. As the 20th Century dawned, a Machine Age was rising in fiery glory, and Mechanically-Advantaged Man seized his world.
The history of steel in the last century will have to wait for another Entry. It's an epic history and a chequered one, revealing the illusion of steel as the ultimate tool of war, but also its reality as the feedstuff of mass consumerism. It begins with the rise of American steel, in perfect harmony with American capitalism, and it's exemplified by Frederick Taylor and a 'second miracle at Bethlehem'.
There is a Ribbon of Fire running around the World.
It runs Day and Night.
It runs out of the Past and into the Future
And it Feeds the World.
Few among Millions know this.
We are the few who tend the Ribbon of Fire.
Long May it Serve us All.