Burton Anthony - The Iron Men

The author would like to thank the following for permission to reproduce illustrations (the remainder are from the authors collection):

Elton Collection, Ironbridge Gorge Museum, 41; Mansell Collection, 129; National Museum of Wales, 41; Pamlin Prints, 85; Richard Thomas & Baldwin, 138; Scottish record office, 105; Shropshire Record Office, 64; Waterways Archive, Gloucester, 63 (bottom) and 66; Windfall Films, 91.

Since cast-iron has got all the rage,

And scarce anythings now made without it;

As I live in this cast-iron age,

I mean to say something about it.

Theres cast-iron coffins and carts,

Theres cast-iron bridges and boats,

Corn-factors with cast-iron hearts,

That Id hang up in cast-iron coats.

We have cast-iron gates and lamp-posts,

We have cast-iron mortars and mills, too;

And our enemies know to their cost

We have plenty of cast-iron pills, too.

We have cast-iron fenders and grates,

We have cast-iron pokers and tongs, sir;

And we soon shall have cast-iron plates,

And cast-iron small-clothes, ere long, sir.

These are just two verses from a broadsheet ballad published in 1822 with the satirical title Humphrey Hardfeatures Description of Cast-iron Inventions. There are three more verses listing still more cast-iron inventions, some real, others imaginary. The song is quoted not for its very limited literary merits, but because it is an indication of just how important iron had become by the beginning of the nineteenth century, so common a part of everyday life that it was seen as an appropriate subject for a popular song sheet. Cast iron was indeed transforming the world, and not merely cast iron: the other two forms wrought iron and, to a lesser extent, steel were also having a profound impact on society as a whole.

The world had entered a New Iron Age, whose influence was arguably to have a far greater impact than the prehistoric period that was first given the name. This book is about the men and women who made this great transformation possible and who worked with the different forms of iron. But to understand exactly what it was that made the new age possible, you have to know just how it differed from the earlier period. We have to step back in time, not just a few years or even centuries, but through the millennia.

There are two intriguing questions to ask about the traditional Iron Age. The first is, how did anyone ever discover that heating a lump of rock could produce a metal something as unlike stone as it is possible to get? The second is, having done that to produce silver, lead, copper and tin, why did it take nearly another 1,500 years before anyone found a practical way of producing iron that could be used for a whole range of different tools and artefacts?

No one can really answer the first question, other than to say silver objects that date back to around 3000 BC have been excavated in Egypt and Mesopotamia. But if you look at the ore galena, it has a silvery metallic sheen that might suggest it would be worth experimenting with it to see what would happen. We know that it is primarily lead sulphide but associated with a little silver and that by roasting it the sulphur can be burned off as sulphur dioxide, leaving metallic lead and silver behind. Once you have heated one interestingly coloured rock it makes sense to try others to see what they might produce.

Copper was almost certainly originally found by people looking for gold. Near the gold deposits were dark nodules with a greenish tinge, and anyone taking the trouble to scratch away the surface would have found native copper buried in the centre. These small lumps of metal were quite difficult to work, but the process could be improved by annealing heating to a high temperature and then slowly cooling.

It was not, perhaps, too big a step to discovering that there were very promising ores, notably copper pyrites, which looked as if they might also produce something worthwhile. However, it was not simple to reduce them to metal. There must have been a long period of experimentation, as heating alone is not enough and eventually they would have found that two stages were necessary. First, the ore had to be roasted, and then heated in some sort of furnace, which would need to be provided with a blast of air to raise the temperature to the point where the molten metal could be produced. The technology of smelting had been born.

The copper ores were frequently found associated with tin, and the combination of these two metals produced the alloy bronze. This had all sorts of advantages over pure copper, with greater strength and hardness, making it valuable for a whole range of products from tools and weapons to ornaments. It was such a huge leap in technology that its introduction was used to mark the start of a whole new period of civilization the Bronze Age, which began around 1600 BC and lasted for over 1,000 years. So, throughout this period metal extraction and working was developing and still iron played, at best, a minor part in the story.

Which brings us to our second question. Why didnt the production of iron get going during all those centuries? The short answer is that it did, but only on a very small scale. Iron could be found naturally in meteorites, but in such small quantities that it was useless for anything much more than ornaments. It took a long time to make the connection between this iron and its ore. Like the other ores, iron ore looks as if it ought to produce something interesting when heated in a furnace, but when it was first tried the result must have been very disappointing. What appeared at the end of the process would have appeared rather like a fossilised sponge, a lump of stone riddled with holes. This is known as a bloom and the actual iron is hidden away inside a mass of slag and cinder.

It takes repeated heatings and hammerings to turn the bloom into wrought iron. Even when iron did appear, it was not immediately obvious what to do with it. Bronze could be given a hard cutting edge by hammering. Do that with cold iron and you do get an edge but it blunts quite easily, much more easily than bronze, so there was no obvious incentive to develop the technology. It was the discovery that a different technique could be used which made the great breakthrough. To produce a hard, sharp edge requires heating, hammering while still red hot and then quenching the hot metal in cold water. The result was a metal that was actually superior to bronze in terms of hardness and durability, and a new age was born.

In Britain, the Iron Age is conventionally described as lasting from the end of the Bronze Age, at around 500 BC, to the arrival of the Romans. The dates simply reflect the fact that archaeologists have given these labels Stone Age, Bronze Age and Iron Age specifically to the prehistoric period before written records. In terms of technology, this first Iron Age could be said to have lasted far longer, right up to the beginning of the sixteenth century.

Technology looks very different, with the benefit of hindsight, from the way it appeared to the workers of the past. We know, thanks to modern scientific investigation, that wrought iron is a very pure form of the metal. Seen under the microscope, it has a fibrous structure, which allows it to be bent and shaped with comparative ease. The aim of the early ironmasters was to produce this form of the metal, which they could work and use to make essential items such as tools and weapons, and everyday objects like nails and horseshoes.

The early furnaces, known as bloomeries, in which iron was made were comparatively crude. At their simplest they were no more than depressions in the ground, which were then filled with the ore and charcoal for use as a fuel, which would be covered by a dome of clay or some other fireproof material. More sophisticated versions would be constructed like stubby chimneys, also made of some sort of fire-resistant material. The resulting bloom would have been quite small. Because the nature of iron was not understood, there was no way of working out how long the ore should be kept in the bloomery, apart from trial and error. If it was not long enough, the reduction would be incomplete. If it was left in too long, some of the carbon would infiltrate the bloom, and what emerged was not wrought iron, but cast iron.