ABSTRACT
But these thin pointed rods or wires must have been forged and hammered out, not drawn through a draw-plate. There is a special classical verb, na,2 meaning to sharpen iron to a point by hammering; and in the West, at any rate, wire-drawing was a late medieval invention. The oldest description of it occurs about + 1130, in the De Diversis Artibus of Theophilus Presbyter (Roger of Helmarshausen),f but it must have started a little before that. By the middle of the + 14th century water-power was applied to the drawing of iron wire, and by the + 15th it was a widespread industry.g Hence it is natural to find a picture of iron wire-drawing in the Thien Kung Khai Wu3 (Exploitation of the Works of Nature) of + 1637,h but so far no earlier illustration has come to light. Sung Ying-Hsing4 says that the drawn and cut-off needles, after having been filed and ground to a sharp point, are packed in a cementation pot over a slow fire and then heated, quenched or tempered so as to give various grades of steel. This is significant because it is much easier to draw soft wrought iron than hard highcarbon steel.
