FEATURES HISTORICAL NOTE

The legend of Benjamin vats of molten iron. Coke was also bet- ter than charcoal at reducing iron oxide in Huntsman and the early steel production. Though first applied to the manufacture of steel as early as 1709, days of modern steel coke wouldn’t be in vogue for steelmak- ing until production methods gradually im- By Omar Fabián proved in the following decades. Shards of glass, meanwhile, were the t was a cold winter night in Sheffield, Samuel Walker made indescribably rapid secret sauce in Huntsman’s recipe. When IEngland, when a cloaked beggar strides in producing crucible steel within added to the crucibles that hosted the knocked on the doors of the local steel a suspiciously short time. And in mid-18th steelmaking reaction, glass would soak foundry seeking shelter. The benevolent century Sheffield, England, enterprising up impurities from the molten metal and crew took pity on the man and ushered craftsmen would go to almost any lengths then be skimmed off the surface after fir- the stranger in, offering the warm shop to gain a foothold in the burgeoning and ing. It was, according to Huntsman family floor as makeshift quarters for the night. lucrative market for high-quality steel. lore, the step Samuel Walker most desired But a closer look at the self-described Benjamin Huntsman never set out to be- to glimpse that Sheffieldian winter night. “tramp” would have revealed him to come the famed inventor of modern steel Walker was hardly the only one to resort be no stranger or beggar. The man was he’s known as today. A master clockmaker to furtive means in this quest. Samuel Walker, a rival steelmaker from by trade, Huntsman had a simple purpose: The French metallurgist Gabriel Jars, nearby Grenoside, and he was on a mis- to make better clock springs than those af- by government commission, descend- sion: to learn how to make what was then forded by the highest-quality steel available ed into Sheffield to acquire the methods the finest steel in the world. to him then. From a materials engineering of steel manufacture earning the town At least, that’s how the story was perspective, the problem was heterogeneity. acclaim in continental Europe. Likely passed down to descendants of Benja- Even the best blister steel imported France’s first international industrial spy, min Huntsman, owner of the factory and from Germany at that time lacked the mi- Jars became well acquainted with the use of the secret for making crucible steel. crostructural uniformity that could keep of coke through his travels to Sheffield While lore and legend tend to bend small parts operating literally like clock- and other English towns. But on the use facts as they’re passed down through gen- work. The steel was formed by diffusing of glass, his diary reveals that he knew erations, they almost always contain some carbon from charcoal into heated wrought only that a “flux” was added to Hunts- nugget of truth. In this case, there are two. iron over days or even weeks. While the man’s crucibles. The composition of that added carbon improved the strength and flux, he lamented, remained a secret. hardness of the final product, the effect Huntsman never patented his process. was, for the most part, only skin-deep. That, many believe, is what made him the The hottest wood- and charcoal-fired fur- frequent target of industrial spies from naces couldn’t reach temperatures high his native England and abroad. Some his- enough to completely melt wrought iron. torians attribute Huntsman’s decision to Most of the diffused carbon, therefore, his deeply religious beliefs. As a devout never quite made it to the iron core. Even member of the Society of Friends (Quak- when small ingots of blister steel were ers), Huntsman shied away from the pub- forged together by hammering to form lic’s eye and may have found any notori- shear steel, the structure of the “sheared” ety gained through his success to conflict material remained largely irregular. Char- with his Quakerism. He even turned down coal also tended to introduce impurities, an invitation to the prestigious Royal So- such as sulfur and phosphorus, which un- ciety for his work on crucible steel. dermined steel’s desirable properties. Thanks to Huntsman, Sheffield would Huntsman would find a solution to the thrive as the world’s hub for modern steel twofold problem of low heat and low pu- production—particularly with the advent rity in one game-changing material and of mass production techniques. Though one deceptively ordinary one. some debt of gratitude is no doubt owed Unlike the charcoal dust used to fuel to the likes of Walker and Jars. Their ef- the production of blister and shear steel, forts to appropriate mastery of steel, du- Huntsman used coke. More carbon-rich bious as they were, represent a recurring coke could actually burn hot enough to element in the story of how the Industrial melt wrought iron. This enabled carbon Revolution was spurred in countless ways from the coke to spread evenly through through other trades and enterprises.

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