I recently finished reading Out of the Fiery Furnace: the Impact of Metals on the History of Mankind, by Robert Raymond. The book was published in 1984 as a kind of companion to a documentary television series of the same name, which was also written and produced by Raymond, I believe for an Australian public television network.
The book is about as big as a textbook or a coffee-table book, and it’s 260 pages long. It pretty much succeeds at its ambitious plan of giving a brief history of metallurgy and its impact on human civilization, from the Chalcolithic Age, which started around 6000 BC, up to the time of the book’s publishing. While being – at least for a naïve person such as myself, a rather comprehensive book, the book is very accessible.
The writing style is very much like the narration style for a documentary TV series. But the structure of the book is also like that of a TV show. There is a definite through line, at least within each chapter, which does read like a TV episode. But the through line might often hop from subject to subject, time period to time period, or location to location, all with the blithe easiness of the short-attention-span format of a TV show.
The main plan of the book follows the movement of civilization out of the Stone Age and into the Chalcolithic, or Copper-Stone Age, into the Copper, Bronze, and Iron Ages. The book then follows civilization into the Dark Ages, then traces its beginning movements out of the Dark Ages, into the Renaissance and into the Industrial Revolution. The book finishes with some discussion regarding man’s apparent movement into the Nuclear Age, which is treated, it seems to me, with a little bit of suspicion.
The first theme that interested and surprised me was the length of time during which Asia and Europe, or at least Asia and the Mediterranean, have been in contact with each other. It seems to me like nowadays, with all our talk of emerging markets, especially our talk of countries like China being emerging markets, we as Americans have an almost romantic perception of our contact with Asia, South America, and Africa as being something new. But the different civilizations of the world have been in touch with each other for a long time.
If anything, what’s interesting is the notion that this might not have been very well known, at least by European and American nations, until the archaeologists began, in the 1960s and 1970s, finding clues of old trade routes with Asian civilizations and Mediterranean societies. From what I understand, Raymond even seems to argue that the birth of the Bronze Age occurred in the Mediterranean (then spreading into Western Europe) because of the contact the Mediterranean civilizations had with the Mediterranean civilizations through the trade routes which came by boat from Asia to Persia and then spread westward on land from Persia.
Bronze is an alloy of copper and tin. But Raymond argues that in the Mediterranean there wasn’t an abundant enough supply of tin for the civilizations to create bronze on the scale in which it has been found in Bronze Age archaeological sites. Raymond believes that the abundant tin also had to be easily recoverable, i.e. to come from alluvial, or river, deposits. But Raymond does not believe there is any evidence for alluvial bronze in the Mediterranean areas which were the seat of the Bronze Age.
Raymond instead argues, based on archaeological discoveries that were new at the time of his writing (and which may, for all I know, now be either old hat or completely disproven – or still new in a sense!), that there was plenty of tin in China, Malaysia, Thailand, and Indonesia.
Raymond proposes that the archaeological evidence indicates that as early as 3000 BC, the alloy of bronze was being made from copper and tin in Northern Thailand. It also indicates that in China, an area known as Ban Chiang became a rather developed center of a Bronze Age civilization in 2000 BC. It is argued that the Asian techniques of creating bronze were passed along, through trade routes, to Cyprus, which was, in the West, the seat of Bronze Age civilization.
A theme of Out of the Fiery Furnace that seems similar to this one points out the fact that the Asian civilizations not only were in contact with at least the Mediterranean civilizations, but that they also were leading innovators and technicians in their own right. When it came to the making of metals, the Asian civilizations were, Raymond argues, in possession of incredible alloying technologies. Not only did they, seemingly, invent the alloy of bronze, but they also routinely performed alloying of various metals, including metals the alloying of which was not common practice in the Western world until relatively recent times.
The Asian civilizations also introduced certain innovations in the processes of smelting metals, or heating the metals in order to separate them in their purity from the ores. These innovations included the invention of the horizontal bellows and the double-acting box bellows.
The bellows are what blow air over fire, to increase the amount of air which is fueling the fire, thus increasing the heat of the fire. Bellows were often impeded in the past by gravity. People working the bellows would have to push the bellows up and down to work them. But the Chinese metal-makers came up with the idea of horizontal bellows, hung from a rod, so that the bellows were works by a back-and-forth motion, free of gravity, rather than an up-and-down motion.
To this innovation was added the concept of the double-acting box bellows, which, instead of providing air to the fire on one of the directions of pushing and pulling the bellows, provided air on both the push and the pull. This continuous provision of air to the fire made it much easier to raise the fire to a certain temperature and keep it there.
Raymond also notes the Chinese for their skill in casting iron. In particular, the bronze works from Xi’an during the Shang dynasty are noted. Some of these works weigh almost a ton, but they were cast in one piece. Raymond notes that the technology for this kind of casting required an almost industrial-scale technology. And, indeed, Raymond points out, traces of this industrial technology were found in recent times by archaeologists.
In addition to casting, however, the Asian civilizations developed a skill in assembly of cast parts, often creating interlocking iron pieces for weapons, such as arrows. The casting and interlocking of parts was different from the techniques of the Near East civilizations of the Bronze and Iron Ages, which often conducted their metal-smithing through hammering, like the ancient flint-knappers of the Stone Age.
The first part of this book also seems to be largely concerned with the decay, decline, and disappearance of civilizations. As a person who used to work in the Park Service, I know that the mystery of a disappearance of a civilization is one of the biggest and most popular mysteries of history. And Raymond speculates over the decline and disappearance of many civilizations in the first part of his book. It’s not really a wonder. The book is 260 pages long. In the first 100 pages, Raymond covers roughly 7,500 years of history. In the last 160 pages, he covers roughly 500 years. There is obviously going to be a decent amount of discussion of decaying civilization packed into a 100-page discussion of 7,500 years of society.
Some of the stories are pretty straightforward. The discussion of the vanished society of Catal Huyuk, which seemed to usher in the Chalcolithic Age in about 6000 BC, is a standard mystery story like the other mystery stories of the vanished societies of time. I don’t remember much discussion of the Anatolian civilization, that of the Timna Valley in the Sinai Peninsula.
The Cypriot, Hittite, and Western European Civilizations were said to have been invaded by what the archaeologists of Raymond’s time called the “sea peoples,” which were assumed to have been peoples from the Balkan regions, in about 1200 BC. This invasion disrupted the supply of tin from Asia and, from what I can tell, dispersed the Hittite civilization, destroyed the Cypriot civilization, and set the newly sprouting Bronze Age of Western Europe back into the Stone Age. But it also ushered in the Iron Age.
The Greek civilization, the first paragon of the Iron Age, was at least partly said to have declined as a result of the tapping out of its mines. The Greeks had many mines in Attica, most famously the Laurion mine. But the mines eventually became unproductive, and as they did, the Greek civilization decayed.
Raymond also connects the story of the Roman empire to mining, most notably the Tartessian or Rio Tinto mine in Spain. Though the fate of Rome wasn’t tied to the fate of this mine, Raymond notes how, as Roman society decayed, the Romans were forced to abandone the mine.
Raymond traces the decline of Roman civilization to an “implosion of mediocrity” in what was really the first technological empire of the world. As Roman civilization decayed, the empire saw increased inflation and decreased economic fortune. As a result, Roman currency declined and Roman society became fragmented. Due to this fragmentation, other forces, such as the Visigoths, were able to invade the Roman empire and take power over its territories. The Visigoths took over Spain, thus cutting Rome off from its valuable Rio Tinto mine. But, as Roman civilization declined, the invading forces did not take up mining on the scale of the Romans. Mines such as the Rio Tinto were abandoned for centuries.
The “decline” of China, if there was one, seems to have been concurrent with the decline of Roman civilization – during the Han dynasty, around 200 AD. Raymond again cites complacency as a cause for the decline of China’s civilization. But, instead of showing China to be a fragmented civilization, he seems to show it as an overly centralized and isolated civilization that saw itself as its own little universe, sort of complete and perfect as it was, with no room for growth or change. Raymond seems to argue that this complacency led to a stagnation of and decline of civilization.
Another interesting theme of the book is how the discovery of metal-making techniques came about. I see four different factors for discovery: accident, non-productive curiosity, distribution of information, and necessity. The birth of the Copper Age seems to have come as a result of both accident and non-productive curiosity.
The recovery of metals, or their separation from ores into a more pure and workable form, is usually achieved through smelting. Smelting is a process which requires three things: the ore, a sufficient amount of heat to melt and separate the metal from the rest of the ore, and a “reductive” atmosphere, which allows the metal to form back into a body separate from the rest of the ore. Copper, in fact, requires a heat of 1084 degrees Celsius. The reductive atmosphere would be an atmosphere of combined oxygen and carbon.
Copper may previously have been worked in its “native,” or found, state, i.e. when there were open deposits of copper big enough to have been worked, for purposes of adornment, such as jewelry. However, there was no way to get enough copper to make it more practical to use for everyday purposes, such as tools, than stone already was. Yet, because of its beauty as an adornment, Raymond argues, copper became highly value to pre-Copper Age civilizations.
Raymond says that toward the end of the Chalcolithic Age, when pottery had developed into a process using kilns, there was finally a vessel and process capable of creating enough heat – as well as a reductive atmosphere (of air and wood-smoke, or carbon) – to allow for the smelting of copper. Copper ores were used as pigments on Chalcolithic pottery, and so they would occasionally, instead of sticking to the vase, turn into splotches, the copper of which would separate and drip onto the floor of the kiln.
The Chalcolithic potters, Raymond says, became curious as to this effect and eventually learned how to duplicate it. They eventually produced copper in enough supply, Raymond seems to argue, that copper became preferred over stone for the making of some daily objects. And thus the Copper Age was born.
The birth of the Bronze Age seems to have been largely a result of the distribution of information, at least in the Western World. As far as I can tell, the birth of the Bronze Age in the East wasn’t discussed to deeply by Raymond.
The birth of the Iron Age was also partly due to the distribution of information – from the Hittites, who held their power over the civilizations they invaded as a result of their iron-making techniques, and who would not share their iron-making techniques until the “sea peoples” invaded them and everybody else in the Near East, causing both their civilization and their technical knowledge to be distributed throughout the Mediterranean.
But the Iron Age also came about as a result of necessity. When the “sea peoples” invaded the Near East in 1200 BC, they cut off trade routes with Persia (I think) and thus with Asia. The tin supply which was necessary for the creation of Bronze was cut off. Bronze was cheaper to make, stronger, and more flexible than iron, or at least iron made by non-Hittite techniques. But Bronze was no longer in supply. So iron had to be used.
So the Mediterranean civlizations began to improve their iron-making processes. The original process of making iron consisted of heating the ore to 1573 degrees Celsius. This created a sort of slag known as bloom iron. Bloom iron was then hammered, or “wrought,” into a shape.
Iron-making technique developed when people began to hammer the iron at a certain temperature. The iron was first heated to 1200 degrees Celsius. It was then hammered, while never being allowed to drop below 800 degrees Celsius, and while also keeping the iron in contact with white-hot charcoal. The charcoal added carbon to the iron, which “steeled” the iron. This high-temperature hammering created iron that was twice as strong as cold-wrought bronze.
The iron was then subjected to a third technique, called “tempering.” In this phase, the iron was quenched in cold water, which added strength, but caused the iron to lose some of its flexibility. The iron was then, however, reheated to 700 degrees Celsius. This made some of the carbon, which caused the loss of flexibility, to evaporate from the surface of the iron. The pure iron of the surface created a kind of jacket of flexibility around the iron. This created a form of iron that was superior to bronze in both strength and flexibility, and allowed the growth of the Iron Age.
As far as I can tell, no further developments seemed necessary in the production of iron until about 1550 AD, when parts of Europe, in particular Britain, underwent what can be thought of as an energy crisis. As populations grew, agriculture increased, and the industries of iron production, ship-making, and glass-making burgeoned, Europe’s forests were decimated. In 1588, Britain imposed a duty against anybody who would use timber as fuel for the production of iron. Not only was fuel becoming scarce, it was also being taxed, making the production of iron more and more expensive all the time.
The fuel for the production of iron was charcoal, or charred wood. The wood was charred until most of the carbon had left it. This made a fuel that could burn efficiently, creating a very hot flame, as well as not tainting iron too much with carbon and sulfur. But now charcoal had to be abandoned, for cost reasons, by iron-makers. Iron-makers began substituting coal for charcoal. But coal had a high carbon content and was therefore impractical to use, even though it was much cheaper than charcoal.
However, a man named Abraham Darby, who had chiefly been involved in the brass business, took a cue from the beer brewing business. The beer brewers, who had learned long ago that the impurities of coal, both carbon and sulfur, destroyed the taste of their beer, but could not use wood for their malting process, began to burn the impurities out of coal, the same way they had been burnt out of wood. This charred coal created by the brewers was called coke. In 1709, Darby began to use coke to make his iron, and he created such good iron so cheaply that iron mining was greatly increased.
In 1856, Henry Bessemer improved one type of iron-making process to make it the foremost of all iron-making processes. This process was called “puddling,” and it created a very pure form of iron known as steel. Since ancient time, steel had been used, first in India, and then in other parts of the world, to create a kind of steel known as “wootz steel,” which made fearsomely sharp swords. However, the puddling process was extremely time- and energy-intensive, and it created only a modest amount of steel.
Bessemer’s innovation was to use the improved bellows technologies of his day to add massive amounts of air to the puddling process. By doing so, Bessemer was able greatly to increase the temperature of the puddles. This made the purification of the iron into steel much quicker and easier than it ever had been. The steel-making puddles were scaled up to previously unheard-of sizes, and steel became a very cheap material. Its strength and flexibility surpassed that of iron. And the use of steel enabled the creation of modern machinery and buildings, such as those we see today.
Another metal was discovered through two different processes. Aluminum had been known of for a long time – some argue since the days of the Romans. But it had such a strong affinity with oxygen that no amount of carbon could cause it to be reduced from its ores. Eventually, in 1809, Humphry Davy posited that the reduction could be achieved through electrolysis, or the usage of electricity. But the use of electricity was only in its infancy, and electrolysis was an impractical way of smelting aluminum.
In 1845, Friederich Wollen created a chemical process for recovering aluminum. He used aluminum chlorate and phosphorous to create a chemical reaction that separated aluminum from its ores. This process was then improved upon by Henri Etienne Saint-Clair Deville in 1854. In 1858 a large supply of ore was noted in the Le Baux area of France. This mass supply of aluminum ore allowed for the commercial production, and perfected chemical techniques, for the production of aluminum.
However, in the 1870s, electrical technologies had developed to the point where the process of electrolysis, first proposed by Sir Humphry Davy in 1809, now became more practical for the recovery of aluminum than the chemical process. The electrical process was perfected by Charles Hall of the United States and Paul Heroult of France.
As well as the production of metals, there were plenty of technologies developed around mining for metals and their ores. Raymond lists three different kinds of difficulties posed for mining: holding up the roofs of mines, keeping the mines lit, and keeping water out of the mines. Despite what I’d assume would be Raymond’s obvious knowledge of the modern travesties of both mine collapses as well as landslides due to strip-mining, Raymond lists the most important historical issue of mines to be water seepage.
The Romans, with their Rio Tinto mine, came up with the first innovation for keeping water out of mines. This was the “noria,” or water-wheel. The norias were actually a kind of relay system of water wheels. These wheels were hand-cranked. A ditched would be formed in one level of the mine. Buckets on the end of the wheel would scoop up water out of the ditch. These buckets would be cranked up the wheel, to a ditch on a higher level of the mine. Another bucket on another wheel would scoop up the water and carry it up higher, until the water was finally dumped outside of the mine.
As the Western world headed into the Dark Ages, mining was neglected, and so the Roman noria technology was not improved upon. But, in the year 800 AD, Charlemagne was crowned the emperor of the Western world by Pope Leo III. Charlemagne, in order to improve the material condition of his empire, re-opened mines.
One major mine was the Rammelsburg mine in the Herz mountaints. This mine was opened in 938. The mine continued production and went deeper and deeper, until the year 1250, when there was so much difficulty with water seepage that the mine had to be shut. The mine reopened, however, in 1370, when the hand-cranked water wheel was improved upon. A treadmill was added to the water-wheel. The wheel was no longer hand-cranked, but powered by the continued walking and pushing motion of men. This allowed for more, and more continuous power.
In 1486, the water-wheel technology was again improved upon when dams, tunnels and waterways were used to create a source of power more powerful and continuous than that of living muscle to power the waterwheels. As a result of this, mines went deeper and deeper.
However, as a result of increased demand for coal after Abraham Darby’s innovation of coking iron in 1709, mines were now being driven so deep that even the water-powered water-wheels were no longer effective enough.
This inspired Thomas Newcome in 1712 to create his pumping engine. The engine was based on the idea that steam, when condensed, creates a partial vacuum, which allows the much heavier air outside this vacuum, to exert a considerable pushing force on the vacuum. Newcome translated these ideas to a piston-and-pump system, which allowed for the pumping of water out of mines to occur with even greater force.
James Watt noted the inefficiencies in Thomas Newcome’s system and created a more efficient engine based on the idea of steam and the partial vacuum. This idea developed into the steam engine. In 1797 Richard Trevithick developed the steam engine which he would then use on his steam-carriage, the predecessor to the locomotive, in 1801.
Raymond discusses other mining technologies, including technologies from Australia, which, after the American gold rush of 1849, had a gold rush of its own, and soon became the developer of the greatest mining technologies in the world. Raymond also discusses some of the modern technologies for mining, which include the usage of immense machinery.
The last theme which really strikes me is the usage of metals. For much of man’s history in the Ages of Metals, it seems to me, man has seen the metals as being of use in four ways: adornment, currency, implements, and containers. Raymond points out that the development of man into a metal-worker would possibly not have occurred, or would not have occurred as quickly as it had, had it not been for the beauty of metals as adornments. Even to this day, the precious metals are sought after by man for jewelry.
The history of man also illustrates how man has used metals – mostly, it seems to me, from my understanding of Raymond, silver – as currency. The ancient Greek mines were largely silver mines. The Romans mined for silver in the Rio Tinto mines, until Roman currency was so debased that the Romans could no longer purchase copper from other places and also had to begin exploiting the Rio Tinto mine for copper as well as silver. The Rio Tinto mine was re-opened by Spain in the 16th century by Phillip the II in order to harvest more silver, to fund the nation’s expansion. And the gold rush was what it was, in both the United States and Australia, because gold was currency. Gold then funded the growth of America into the industrial giant it is today.
The use of metals in a practical sense is, I think, divisible into two types: implements (tools, utensils, etc.) and containers. I think the same could be said of stone and pottery. While weaving could also be thought of as of use for implements and containers, I think it also has the character of being an insulator.
Contrasted, however, with insulation, metal can also be seen as a conductor. But – I think – it was not until the discovery of electricity that metal was seen as being a conductor. When metal began to be seen as a conductor, man obviously entered a new age. Metal has likely always been seen as a conductor of heat, but probably mostly by accident, and its character as a conductor in cooking was likely only seen as an accident or something ancillary to its character as a container for objects being cooked.
However, with the advent of electricity, metal took on a different character. As an implement or container, metal was an object which acted only as man provided the motive force for its action. But now, as a conductor, metal itself carried, and then provided that motive force. To be sure, that motive force was at first provided by another object – namely a power generator. But the metal itself, not man as a carrier, moved that motive force to its end point, which may have been another agent of motive force, or which may have been an expender of that force, such as a light bulb.
The final development of the metals, I would assume, has come from the Nuclear Age. The metals have abstracted their character as implement into what it really is – namely an agent of motive force, activated. But the metals have gone, as implement, into being motive force itself. And, once this happened, I believe, it became much easier for man to see that motive force, even conduction, was not required to have something we would generally think of as “material” to carry it. Thus we have developed the usage of radio waves and so forth.
As I said before, Out of the Fiery Furnace seems to hover at this end point, the Nuclear Age, with a certain amount of caution. Partly, no doubt, that is because of the massive destruction of which nuclear power is capable. But partly, it may also be because the Nuclear Age has managed to usher in an age in which man is dependent, for the development of his civilization, on something that is not a metal – something which may not even be considered to be very material at all.