How did Damascus gain such a reputation? After all, fine bronze work by Peking Man had been known thousands of years before, while Japanese curved swords, the classic samurai blades, date back to around A.D. 800. Yet for a significant period the sharpest, most sought-after weapons came from Damascus, crafted from strong, light metal whose surface was patterned like the grain in wood. The city’s swordsmiths would use a mixture of iron and carbon with traces of silicon and sulfur (in so-called wootz ingots) from India, which would be hammered and heated into deadly weapons. The process produced the special “damask pattern,” the “damascening” or “watering” that swordsmen so prized. So to two further questions: What special technology led to such a reputation? And why did Damascene craft come to so sudden an end, all those centuries ago?
In January 2000 Discovery magazine reported that the secret of the remarkable technology was emerging from the thousand-year-old ruins of the city of Gyaur Kala in eastern Turkmenistan, which had disclosed the remains of an ancient factory, including a high-temperature furnace fed with air from below. The innumerable steel-beaded clay shards scattered among the surrounding sands appeared to be the remains of thick-walled crucibles in which steel had been fired at temperatures of up to 2,500 degrees Celsius—far higher than any other steelmaker could then command. Under analysis, the steel revealed a mixture of low-carbon and high-carbon iron alloys, which the ancient ironmasters seem to have combined in an advanced process called “cofusion” to create a high-strength steel.8
Just under a year after this article, the London Times published an account of how, twelve years before, a professor of materials science and engineering had set out to reproduce swords similar to those of the Damascene swordsmiths. Scrutinizing pieces of a Damascene sword donated by a Swiss museum, John Verhoeven, from Iowa State University, found that the highly prized grain effect was created by clusters of iron carbide, which show up as white against the dark steel. How to create that effect? He teamed up with Alfred Pendray, a Florida blacksmith, who discovered that the clusters were induced by repeated cycles of heating and cooling. As hot liquid metal cools, impurities separate out, the ferric carbide particles congregating and growing around these impurities at each heating and cooling. It takes about six cycles to reach the damask pattern. Simple, once you know.9
Over the years, fewer and fewer blades came out of Damascus, and after the fifteenth century production there virtually ceased. In Verhoeven’s view, this was because changes in world trade transformed the content of the ingots until they no longer offered the right blend of impurities. So Damascene steel fell victim to the international commodity market. For some years the city’s reputation continued to overshadow those of other established centers of the craft—Yemen, Q’al’a in the Arabian desert, and India, so often a pacemaker and fundamental supplier—as Damascus became the point of distribution for fine weapons produced elsewhere. Much of its trade was with the West, which probably explains the reputation of “Damascene” blades.
ICONFESS THAT I AM NO SCIENTIST AND WAS MYSTIFIED BY THESE various processes. What is the difference between iron and steel? Why is carbon so important? What does the cycle of heating and cooling achieve, and why were the temperatures at which blades were “quenched” so guarded a secret?‡
I fell by luck upon The New Science of Strong Materials by Professor James E. Gordon, a Scottish academic with a tart sense of humor (the subtitle of his book is “Why You Don’t Fall Through the Floor”). “Broadly speaking,” Gordon writes, “there are two problems with all metals—extraction metallurgy, the separation of the metal from its ore; and physical metallurgy, which is how to get the metal into its most useful condition of hardness, strength and toughness.”11 The latter is achieved through “the sharp instrument of fire,” a power available to mankind for four hundred thousand years. As that keen fencer Michelangelo wrote in one of his sonnets, “It is with fire that blacksmiths iron subdue / Unto fair form, the image of their thought.” With fire, certainly, it was possible to create a whole new class of metals, and it is no accident that the one technologist in Greek mythology to have been given the rank of a major god was Hephaestus, smith and purveyor of weapons to the Olympians. (Prometheus, who fashioned man out of clay, is only a demigod.)
Pure copper, Gordon explains, is a soft metal and cannot be given an effective cutting edge. It is made up of layers of minute crystals; to hold the crystals together, one needs grit. Yet if one adds a particular, yet softer metal—tin—one obtains bronze; tin’s impurities combine with copper to make a far stronger alloy. Much stronger, in fact: about 5 percent tin to 95 percent copper makes bronze three times as hard as the copper alone. Bronze was discovered in the Middle East around 3800 B.C. and became, as Jacob Bronowski put it, “a material for all purposes, the plastic of its age.”12
After bronze came iron, then the steels, a family of iron alloys. By 2500 B.C., iron, which the Sumerians called “a metal from heaven,” was already in use. (The word “iron” has close English connections to the word “ire” but is also related to “holiness,” “frenzy,” and “defecation”—all having the common denominator “fast-moving.”§) Societies started to make swords from iron without realizing what the processes they employed did to the metals under hammer and forge—they simply judged by the results. Not until 1860, quite late in the first industrial revolution, did people start to understand carbon’s role in the steelmaking process. To make cast iron, one needs about 4 percent carbon (about as much as pure iron will hold); to make steel, one needs iron and 1 percent carbon or less.
That carbon would affect the behavior of iron is easy enough to understand, but these percentages seem so small. Gordon clarifies all this by explaining that the percentage is calculated by weight, not volume—and since carbon atoms are much lighter than iron atoms, the actual volume of carbon in steel is about 20 percent.
The difficulty facing the primitive metallurgist was to get a furnace hot enough to fuse metal and carbon. Bronze melts at between 900 and 1,000 degrees Celsius, just within reach of the ordinary wood fire. Pure iron melts at 1,535 degrees—for centuries beyond the range of technology, which is what makes the achievements of the Damascene swordsmiths so astonishing. However, even small amounts (by weight) of carbon will lower the melting point of iron considerably, and carbon fuel, usually in the form of charcoal, was often used to heat iron ore. If just over 4 percent of carbon seeped into the metal, it would lower the melting point by nearly 400 degrees, a temperature just about attainable with a blown charcoal fire. The Damascenes must have discovered this technique for themselves, after which it fell out of memory for several centuries.
Hammering iron has two effects: first, it squeezes out most impurities, including what is known as “slag,” a dirty brown or gray substance formed from mixing with lime or limestone; second, it reduces the carbon content of the iron, leaving only small amounts of silicon and slag, both of which protect the wrought iron from becoming too soft. When iron is heated and beaten into elongated billets, it develops a particular kind of oxide coating. A smith would then double the metal over like a piece of pastry, trapping the oxidized film between layers of hot metal. This folding process would be repeated about a dozen times, which is why top-grade swords when broken show a delicate wavy pattern, each line the sign of a beating operation. But the alloy will stand a maximum of only about fifteen such procedures; thereafter blades begin to weaken (our word “meager” is related to the French word “marcrosse,” meaning “endlessly thinned out”).
Next comes the crucial “quenching” phase. This hardens the steel as it progresses from its “austenite” to its “martensite” state—that is, iron once again deprived of carbon. The metal loses heat very rapidly, but a smith must still quench a blade, that is, plunge it into a cool liquid. If a blade is quenched too swiftly, cracks appear, especially if water rather than oil is used. So quenching hardens, tempering softens; the trick is to find the ideal balance. Preparing a steel blade entails a series of
approximations, each process going too far in one direction and being offset by the next.‖
Quenching calls upon a further special skill, and at this point swordmaking enters into mythology. Some of the myths are true, however: it is better to quench a blade in urine because it cools more quickly than water. Urine contains urea and ammonia, both nitrogen compounds, which spread into the iron, forming needlelike crystals of iron nitride. These contribute to the strength of a blade, but iron has to be very hot for the nitrogen compounds to enter it—dogs do not harden lampposts.a
I made out the following list:
1. Cast iron—hard but brittle, with too much carbon, i.e., charcoal.
2. Blade heated—all carbon removed—metal now too soft.
3. Blade reheated—some carbon put back in again.
4. Blade quenched, to harden it—thus becoming too brittle.
5. Blade, now tempered, reheated to 220–450°C—as it cools, becomes softer.
So much for my scientific education.
EACH OF THE VARIOUS CENTERS ASSOCIATED WITH SWORDMAKING has, unsurprisingly, been keen to assert its primacy over its rivals. Over the centuries Toledo steel has had many admirers. Andrew Steinmetz asserts that “the sword-blades of Toledo have always carried off the palm as trusty weapons; proof against all violence without breaking. One was shown at the recent French Exhibition bent into a complete circle, and yet straight as an arrow on being released.”14 Even the villainous Sheriff of Nottingham (played by Alan Rickman) in the 1990s film Robin Hood: Prince of Thieves muses to his cousin, as he whets his sword, “Spanish steel … so much stronger than our native blades.”
Yet blades were fashioned in cities such as Valencia, Granada, and Zaragoza as well as Toledo. What gave to this one city such a special fame?
Toledo is situated in La Mancha, Don Quixote’s stomping ground, and has always excelled in the arts. Its swordmaking reputation rests in large part on its tornerías, the engines that shape the blades. The Latin poet Grattius Faliscus writes of the Toledo knives that hunters carried in their belts. Even Shakespeare insists that Othello’s sword came from Toledo. But the city’s swordmaking dates back even earlier, to the Bronze Age. The reputation of Toledo’s swordsmiths was further enhanced by local myths claiming that Hercules had added the building of Toledo to his labors and that the first hammer and anvil had been dropped on the town from the heavens, to improve the human condition. The notion even grew that Saint Joseph, the accepted father of Jesus Christ, had been not a carpenter but a smith.b
An armorer’s shop in eighteenth-century Paris, designed by Diderot for his Encyclopédie méthodique, 1751–1775. Practice—or maybe something more deadly—continues outside in the street. (illustration credit 5.1)
When the Romans occupied Hispania, they quickly adopted the Spanish sword, gradually abandoning their inferior flat, heavy blade. During their occupation Toledo advanced significantly, gaining ascendancy thanks to the excellence of its swordmaking and its strategic geographical situation.
The Roman order was eventually superseded by the Visigoths, under whom swordmaking declined. In 711 the Visigoths gave way to Arab rule, a bloody period during which the city’s swordmaking was forced underground. Once Toledo-born Abd-er-Rahman III (r. 912–61) ascended to the caliphate, the industry revived—recognized guilds developed and there emerged aminin, who presided over each work community and controlled standards and productivity. Toledo further enhanced its reputation when Syrian smiths fled from the turbulent caliphate of Damascus and established their workshops in Arab-dominated Spain.
Toledo claimed that its artisans succeeded in improving on the work of Damascus by eliminating the iron veins left by their predecessors’ techniques and by developing what they called their “alma de hierro”—literally, “soul of iron,” a layer of steel that covered the intrusive vein and assured the blade a greater resilience; but this is a doubtful advertising line, since the surface rainbow effects in Damascene blades were a large part of their mystique.
The prestige of Toledo was next enhanced by the arrival around 1470 of Julián del Rey, “The Moor,” a respected smith and excellent swordsman. Eight years later he was baptized, with the first king of all the Spanish kingdoms, Ferdinand II of Aragon, as his godfather. Such was Julián’s prowess that Arab swords thereafter would carry his trademark, a small dog (perrillo), which came to be taken as a fox. Soon “fox-blade” meant any good sword—hence the anachronistic reference in Henry V, Act IV, Scene 4: “Thou diest on point of fox.”
At the beginning of the thirteenth century an influx of Arab warriors known as “zenete,” hispanized as jinetes, had introduced new and effective fighting techniques. This gave rise to the jineta sword, the weapon of choice of Moslems warring against Christians. By the fifteenth century the Christians too were using such swords—and these were largely manufactured in Toledo.15 Even Toledo’s most renowned artist, the Cretan El Greco, sported a jineta sword and reproduces it in at least two of his self-portraits. The swordsmiths of the city congregated into one street, “La Calle de Las Armas,” where the rules of their craft could be better enforced. Punzones (“punches”) were set as marks of workshop identity on all swords made in the city. Apprentices were expected to pass tough exams, which included tests of their ability to work with leather, thread, netting, velvet, and silk. They were also expected to make jinetas for use in juegos de canas, popular jousting tournaments that took place on feast days. Two bands of eight horsemen each got up in their finest armor would attack one another within a fixed set of rules and movements—very similar, in fact, to the old Roman version—in the first recorded example of competitive sporting swordplay in Spain.
During these years Spanish Moslem swordsmiths cooperated freely with their colleagues in Syria and so learned the craft of forging steel through the process already described—combining iron with an array of other elements such as carbon, silicon, sulfur, phosphorus, nickel, and chromium, which brought about the desired balance of hardness and flexibility. By 1561, however, the royal court moved to Madrid, and Toledo began to lose its importance. The population dropped from 125,000 to 55,000 (in 1594), exacerbated by plague at the end of the century. Apart from that, the sword was being replaced by the gun.
Toledo continued to make swords, but in 1664 a last surge of hyperinflation hit the country and a financial crisis in 1680 ruined whatever remained of the Castilian economy. Artisans abandoned their craft, and guilds everywhere were dissolved. So few native swordsmiths remained in Toledo that it suffered the indignity of having to induct foreign specialists. In 1760 the visionary King Carlos III, aware how far the rot had gone, recruited from Valencia its only remaining skilled swordmaker, seventy-year-old Luis Calixto, whom he directed to bring to Toledo the few master craftsmen he could find. In 1780 a Royal Manufactury was constructed on the outskirts of Toledo.
In the spring of 2000 I went to see Toledo for myself. A well-established stop on the tourist route, it offers swords everywhere, of all shapes and sizes—enough on show to equip an army. The city boasts two main swordmaking companies now, plus a smaller concern that specializes in bullfighting swords; but that apart, everything is made for ornamental or kitchen use. It was all vaguely depressing, as if real life had deserted the body of the town.
Throughout the nineteenth century Toledo remained a byword for excellence in swordmaking, but although the town asserts today that it has produced “the finest and most beautiful swords in the world” for centuries, from at least the early fifteenth century onward it had two principal rivals: Passau, on the Danube, at the border between Austria and Bavaria, and Solingen, a small town in the Wupper Valley in the Rhineland, near Cologne.
IT WAS WHILE CLEARING LAND FOR FARMING THAT THE INHABITANTS of the scattered villages of the Wupper Valley first discovered that veins of plentiful and easily obtainable iron ore were to be found just below the earth. Nearby beechwood forests could provide the charcoal, the numerous streams and rivers the necessary power. With such
abundant resources, craftsmen could make high-quality, long, flexible steel swords. That alone did not lead to high steel craftsmanship: the people of Solingen did the rest. Even King Philip II of Spain, an Austrian Habsburg, flaunted a sword created there, as if to keep the craftsmen of Toledo in their place. The German town was greatly helped by the Knights of Saint John’s decision to settle in the area, and during the Crusades a chosen number of the local swordmakers would accompany these knights abroad, enabling them to see for themselves the practices and techniques of foreign rivals.
A late-sixteenth-century swordsmith’s, a contemporary depiction by the Italian Bernardino Poccetti. Craftsmen grind and polish blades while a variety of swords, daggers, and other arms are displayed for sale. (illustration credit 5.2)
By the fifteenth century, the reputation of the “City of Swords” shone bright. In Solingen the term “Kotten” does not refer to a shed or cottage, as it does elsewhere, but rather to a grinding workshop operated by waterpower. These Kotten first appeared in the river valleys and on the banks of the Wupper. Contrary to practice elsewhere, twin workshops—Doppelkotten—were set up, so that hammering and quenching went side by side. By 1684 there were 109 such shops. A German historian has noted that the craftsmen would take the iron ore “and melt it in draught and smelting ovens and fashion it into axes, spades and weapons.”16 It was these “draught and smelting ovens” that enabled Solingen’s smiths to rival the steel refinement of Damascus.
Yet the artisans of Solingen were not the only craftsmen of their kind. Bladesmiths elsewhere, in Prussia as well as in Württemberg, Saxony, and the lands beyond, sought to emulate the quality and reputation of the Solingen smiths. Some went so far as to mark their blades “Solingen,” when the true place of manufacture was as far away as Spain or Russia. For centuries, the most famous mark remained that of a running wolf, still used to identify blades made in the Solingen and Passau regions.
By the Sword Page 16