I tried to do some translation research on the word Moire'. It appears to be a French word with perhaps a Norwegian language background. The translation is a combination of the concepts of "shimmering effect" and "memory". Perhaps similar to the ripples that continue after a rock is thrown into water. Or in the case of damascus steel, the effects remaining in the damascus pattern as a result of hammer blows on the metal. The English Ruban naming of the pattern, must be derived by attributing the pattern's appearance to something found in Celtic artwork.
By manufacturing the lopin, to make the iron and steel barrel from which I come to speak, it arrived sometimes that the forgeur is misled, with the of place; ce qui avait confondu toutes les mises ensemble. The canonnier, unaware of the error made, once the forged and déroché gun, is found amazed to see appearing a completely odd nuance, imitating the effet de moire. It is this the Canon Moire' was called.
I read this paragraph as saying that the barrel welder discovers that he has made a barrel from poorly prepared damascus rods. The iron and/or steel not sufficiently welded and folded to homogenize the scrap pieces before it was stacked in the lopin. This results in a random appearing patterning, caused by the individual scrap pieces showing in the etched barrel. ce qui avait confondu toutes les mises ensemble. = which had confounded all put together
Japanese swordsmiths took homogenization of blade steel to the extreme. They purportedly folded their steel, up to a million layers. Still after this concerted effort to homogenize the metal, Japanese blades have been described as being made of "watered steel". The etched blades displaying faint ghostly swirls, resembling water spots on a table top.
Might be just a round punch making regular dimples along an untwisted layered bar.
I won't argue against Craig's thoughts too strongly. He is correct that punching the layered bar will facilitate creating the pattern shown in the photo. However, the effects of the multitude of hammer blows that fell on the barrel tube is probably sufficient to cause the pattern. Modern damascus smiths call this "Random Pattern" damascus. This term coined probably in the mid 1970's. Bladesmiths who use this pattern, usually will intentionally leave hammer marks on the surface of the forged blade. Grinding away the hammer marks, rather than forging the blade surface smooth, will develop a degree of patterning in the steel.
Even careful reforging to a smaller diameter might show the logical elongation of the patterns that were already formed in the larger bore barrel.
Craig,
I don't wish for my comments to seem that I am picking on your analysis'.
You are correct that on the face of it, it seems logical that forging a barrel tube smaller would elongate it. However, it does not. This is one of the interesting pieces of the puzzle, regarding forging small bore barrel tubes.
Forging a solid round rod smaller, will definitely cause it to elongate. The rod is compressed between the hammer and the anvil, causing the material to move laterally. The lateral movement of the metal will lengthen the rod.
In forging a hollow tube to a smaller diameter, the upper surface of the tube is not supported by the anvil. Without the anvil to support the underside of the metal, there will be no compression of it, thus no elongation of the tube. Hammering on the tube, will only drive the sides of the tube closer together. I'll dig into this subject deeper, when I post the thread on forging small bore barrel tubes.
