Before revision: The presence of phosphorus (without carbon) produces a ductile iron suitable for wire drawing for piano wire Antique music wire, manufactured at a time when mass-produced carbon-steels were available, was found to have low carbon and high phosphorus; iron with high phosphorus content, normally causing brittleness when worked cold, was easily drawn into music wires.
After revision: Antique music wire, manufactured at a time when mass-produced carbon-steels were available, was found to have low carbon and high phosphorus; iron with high phosphorus content, normally causing brittleness when worked cold, was easily drawn into music wires.