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Further to Peter's comments, the best wrought iron (meaning iron that was uniformly low in carbon content, lacking steely patches, and as near free of slag and phosphorus as possibly) was required for drawing wire. In the USA this requirement kept the bloomery industry alive in the Adirondacks and New Jersey much longer that would otherwise have been possible. (The last American bloomery closed in 1900). The main customers for bloomery iron were the makers of suspension cable (as in the Brooklyn Bridge) and the makers of crucible steel. For more detail see Robert Gordon's splendid book American Iron 1607-1900 (Baltimore, Johns Hopkins University Press, 1996), especially chapter 9 (Iron Quality). David Killick Associate Professor Department of Anthropology University of Arizona Tucson, AZ 85721-0030 phone: (520) 621-8685 fax: (520) 621-2088 -----Original Message----- From: Peter Hutchison [SMTP:[log in to unmask]] Sent: Tuesday, November 06, 2001 9:26 PM To: [log in to unmask] Subject: Re: Meaning of the term Slitting? Mark 19th century wrought iron and medieval wrought iron are quite different. Most 19th century wrought iron was a fairly cheap mass produced product. Peter Nothover has examined some railway track and was apalled at how poor the quality was. Similar comments were made about the iron used for the Titanic. The best was reserved for jobs such as anchor and lifting chains. The iron used for these had to be capable of being tied hot into a loose overhand knot and pulled up tight cold without any cracking. Medieval wrought iron was an expensive craft product. It was probably a matter of careful attention to the production variables such as the ore used, the charcoal, and the temperature at which the bloom was made and forged. The final test was probably to try a bit. Like all Medieval crafts almost nothing was written down perhaps because the craftmen could not read or write. I expect there were horses for courses. The wire drawers would know or employ a smith who usually produced the right quality. Drawn wire is, of course, quite different from the sizing operation you have described. I do not see how you would tell whether the base material was slit from a plate by examining the finished wire. The modern steel industry (and most other industry) works in a similar manner, though controlling the process is more accurate. Testing (which is really only trying a bit) is to find out whether you got it right. If you didn't all the processing is wasted. Only at a very few points can things possibly be put right. As in Medieval times you may be able to sell the lower grade material. In the 1960s if it was sheet steel and flattish someone would buy it but not now. Peter Hutchison