: Annealing furnaces located at the Ohio Malleable Iron Company, a Columbus-based subsidiary of the Jeffrey Manufacturing Company, Columbus, Ohio, 1922. In order to toughen brittle metal, annealing was a process where metal was heated and then slowly cooled. View on Ohio Memory.
: AL01429 Subjects
: Ohio Malleable Iron Company (Columbus, Ohio); Ohio Economy--Economy--Business Places
: Columbus (Ohio)