主题：我写的关于铁问题的research paper，请大家批评指正 -- 鸭绿江

写这个research paper还是有私心的，academic writing课要求写一个research paper,所以立即想到了这个题目，回头找了找资料，现如今在整个欧美，只有一个叫Wagner, Donald B.的哥们儿研究中国的铁的问题（在我找到的近年的资料里确实如此）。而我对中国铁的问题的看法是，很有可能比中亚以西发明（发现）的晚，而且中国什么时候出现铁尚未有定论，所以这个问题没法谈，但是中国的铁制品发展却是很快的，前后约300年左右，即普及（主要是个人推测，战国末，齐楚以盐铁致富，那么出现的时期往前推个一二百年，大约是公元前3，4 百年的样子，然后在公元前一百年左右，即文景之治和汉武帝反击匈奴时大规模普及）不像是西方，很不平均，这一点，我的research paper里有论述。

坛子里水深，千万别留情面，倘若有错，只管批就是了，还有就是，我现在只来得及把英文版的发出来，最近学习太忙，可能一两个礼拜后把中文的贴出，或者那个兄弟帮个忙，在这里先谢过了。

Comparison of History of Iron Smelting in Western and China

Iron is one of most important natural resources used by people. Not only because its qualities in natural, but only its abundance all over the world. The history of people using iron can be traced back to at least 3000 BC. The Iron Ages does not begin until about 1200 B.C. Different regions have different times of entering Iron Ages. Comparing with their west counterparts, people in ancient China area had a late start entering the Iron Ages. The history of iron using in China is generally ignored in historian discussions. There are a few comprehensive studies of history of iron usage and smelting in ancient China. In fact, the iron producing techniques used by ancient Chinese were more advanced than Western World. Not long after ancient Chinese began to use iron, iron was more commonly used in China than in west. In the paper, I try to explain that ancient Chinese have technical advantages of using iron, and iron usage was popularized faster in China than in the rest of the world.

Metallic iron was known and used for ornamental purposes and weapons in prehistoric ages; the earliest specimen still extant, a group of oxidized iron beads found in Egypt, dates from about 4000 B.C. And there are other occasional smelting of meteoritic irons to build decorative weapons. Since meteoric irons are rare and hard in nature, they are very precious. The archaeological term Iron Ages properly applies only to the period when iron was used extensively for utilitarian purposes, as in tools, as well as for ornamentation.

Around 1400 B.C., the knowledge of smelting iron was first discovered by Hittites in the West Asia area, somewhere around today’s Turkey. In a letter dates from between 1275 B.C. to 1250 B.C., Hittite king wrote to a contemporary monarch, in which he apologized for not being able to provide more iron for dagger-blades from Kizzuwatna. Thus, the beginning of the Iron Ages can be traced to about 1200 B.C. According to Snodgrass, there are three-stages for development of the Iron Ages: “first, iron is known but is rare, and is used mainly for decoration; second, iron is used as a ‘working metal’ for weapons and tools, but bronze dominates for practical implements; third, iron is the main working metal, although it does not completely replace bronze.” Further, Snodgrass identifies that Cyprus, Greece, Syria and Palestine enter stage two by 1200 B.C., and says Cyprus is the first iron-based economy, entering stage 3 around 1100 B.C. Aegean islands begins their stage 3 by 1050 B.C. Crete is about 50 years behind, and western Greece and western Mediterranean Europe is up to 300 years latter. Iron Ages here is off course in a relative sense. To say the above regions iron-based economy is a distortion, since iron moved around in a very restricted relation of exchange, and away from everyday activity. Braudel observed that “the Iron Ages had hardly begun for the entire chronological span of this book [A.D. 1400-1800]. The farther back in time one goes from the great turning point of the industrial revolution, the small the role played by iron …”

There are still debates of why there was a sudden adoption of iron among archaeologists and historians. One popular theory is that warfare and mass migrations beginning around 1200 B.C. disrupted the regional trade, including copper and tin, which are two raw materials of making bronze, so that forcing a switch from bronze to iron. Egypt, on the other hand, did not experience such a rapid transition from the bronze to iron ages: although Egyptian smiths did produce iron artifacts, bronze remained in widespread use there until about 500 B.C.

For readers unfamiliar with iron metallurgy, some explanations are necessary in order to follow my arguments. In the Bronze Ages, iron oxides, which are widely distributed, were used as flux of smelting bronze, in order to reduce the melting point. Some iron tools or weapons discovered in some major bronze smelting centers might be the by-products of the bronze making process. Iron in sponge form is called wrought iron, which has a melting point of 850ºC. Cast iron has a smelting point of 1170ºC. Two kinds of irons are different in their carbon content, which affects not only their qualities but also their fusibility. Wrought iron is free of carbon, and it becomes cast iron when the iron content reaches two and one half percent. Carbon absorbed by iron makes it harder. Therefore, wrought iron is soft, and cast iron is hard and brittle. This explains why Roman soldiers always have to run back and forth during the battle in order to straighten their bended sorts.

Not until middle Ages, iron made by the people in the west was wrought iron. In the Western, people used similar equipments of smelting bronze to make iron, which made the process labour consuming and costly, since iron has a higher smelting point than bronze, 1530ºC, which can never be reached during the smelting process in the Western. The Greek historian Diodorus, writing in about 25 B.C., says that Aethalia (the island of Elba) abounds in ironstone, “this the natives dig and cut out of the ground to melt, in order to make iron, much of which metal is in this sort of stone. The workmen employed first cut the stones in pieces, and then melt them in furnaces built and prepared for purpose. In these furnaces the stones, by the violent heat of the fire, are melted into several lumps, in form like great sponges, which the merchants buy for truck and exchange for truck and exchange for other wares.” And then these lumps, he continues, are bought by “the smiths, who beat and fashion them into all sorts of tools.” As we can see, the process of smelting iron is very costly. Thus, Western people never naturally wanted to use iron to replace bronze, but the scarcity of tin and copper forced them to do so. In ancient Greece area, between 1125 B.C. and 1025 B.C., the number of bronze items excavated is over iron; between 1025 B.C. and 900 B.C., iron items are more than bronze items; between 900 B.C. and 825 B.C., the iron items is out numbered by bronze items again, and the ratio of bronze over iron is higher than of 1125 to 1025 B.C. period. This observation suggests that iron did not completely displace bronze in the early period suggested by Snodgrass. The period of iron items dominates bronze items above was the time that raw materials of making bronze were in shortage. As in later times, copper and tin became scare and they were hard to be controlled by elites of the countries. Western began to use iron tools and weapons, not because their better qualities and cost efficiency, but their abundance.

Now, let us look at the Chinese story. By the Shang dynasty (about 1500 BC), which is the Chinese dynasty with the earliest-known written records, metal casting or foundry skills had been developed to a remarkable degree. Bronze objects of very large size and complexity of shape, even by modern standards, were produced in this period. The large objects are for ornamental, ceremonial and ritual uses and represented individual works of art. Bronze weapons also were produced in large numbers so that organized armies could engage in the warfare.

Iron was used in China as early as at least 1500 B.C. (Shang dyansty), but in meteoritic forms. Chinese smiths at that time, hot forged meteoritic iron and produced small edges to be cast into bronze axes and other edged weapons. The question of whether these smiths developed their techniques themselves is still in discussion, but the probability of self invention is high. According to Wagner, iron smelting began in the capital of southern state of Wu, in around 500 B.C. Some ancient Chinese documents also suggest that smelted iron had been used in China earlier than 500 B.C. In the Tso Chuan, which is considered to have been written not later than 300 B.C., stated that in 513 B.C. two officials of the state of Chin requisitioned 650 pounds of iron in order to cast a tripod on which the criminal code was inscribed. In the Kuo Yu, considered to be a compilation of historical anecdotes in part at least as old as 200 B.C., there is a description of culture in the Zhou dynasty (1200 B.C. or later, to 600 B.C.) that lists the various implements and tools of iron that a farmer, a woodworker, and a seamstress should have. The reason why iron smelting began in the south is similar to the Western story. The southern state of Wu, is located at today’s Jiangsu Province, China, where copper and tin are rare but rich in iron. In ancient China, northern region of China, where copper and tin are abundant, considered people in the south region, such as Wu, as “barbarians”. Therefore, there was little trade between north and south, and there is always warfare between the two. Even there were trades; the copper and tin would be expensive. As a result, Wu was forced to use iron as their primary material for tools and weapons.

Unlike in the west world, the way of these ancient Chinese smelting irons is different and more efficient. There are two differences of iron smelting in China and in the west. First, Chinese use coal rather than charcoal as fuel of iron smelting. The first recorded Western attempts to use coal as fuel in iron making were made in England in the 1700 A.D. and were not brought to success until 100 years later. Northern part of China, where coal is abundant, first used coal as fuel. Southern part of China later used coal as fuel instead of charcoal. Northern region might have long been familiar with iron, but not able to produce quality iron suitable for sword making. In addition, northern region had more resources of copper and tin than southern China. This might be the reason why people in the south region urged to invent new technique of iron smelting. Second, with charcoal smiths in the southern state of Wu developed an iron smelting technology that would not be practiced in Europe until Middle Ages. In Wu, iron smelters achieved a temperature of 1130ºC, hot enough to be considered a blast furnace. At this temperature, iron combines with 4.3 percent carbon and melts. As a liquid, iron can be cast into molds, a method far less laborious than individually forging each piece of iron from bloomery. Europe, however, continue to produce iron in a bloomery, which is not cost efficient. This is the main reason why use of irons spread slower in Europe than in China in various sectors of daily lives and productions.

The products of blast furnace are cast iron. Since cast iron only appears in the rest of the world occasionally at early Iron Ages, the blast furnace must be an independent invention of the Chinese. Cast iron is rather brittle and unsuitable for striking implements. It can, however, be decarburized to steel or wrought iron by heating it in air for several days. In China, these ironworking methods spread northward, and by 300 BC, iron was the material of choice throughout China for most tools and weapons. A mass grave in Hebei Province, dated to the early 300 B.C., contains several soldiers buried with their weapons and other equipment. The artifacts recovered from this grave are variously made of wrought iron, cast iron, and steel, with only a few, probably ornamental, bronze weapons.

Another theory proposed earlier by Read is that Coal used in China has its unique qualities. Coal is likely to be high in sulphur, which enters the iron and spoils its quality. However, Shanxi coal, which was used by intensively in the northern region, happens to be low in sulphur. In addition, the coal also contains abundant iron phosphate. The high phosphorus in iron tends to decrease the melting point of iron. When iron containing 6.7 percent phosphorus, it has a melting point of about 980ºC, which is lower than copper of 200ºC. The uniqueness of Chinese coal may be an explanation why Chinese iron smelting method did not spread to India, and why the rest of the world did not use coal as fuel of iron smelting.

Although Chinese had a late start of iron smelting, its techniques of iron smelting developed much faster than the Western. Today, the largest iron casting item is still in existence, which is a cast-iron lion about 20 feet high and 18 feet long; cast in about 954 A.D. There is a parallel between the Western world and Chinese history in iron smelting. Both of them began to use iron as inferior substitutes as bronze, until advanced smith techniques was developed in south region China. Ever since blast furnace was introduced, iron usage dominates bronze. However, in Europe, iron smelting was still a costly process.