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Amgueddfa Cymru
Typed in black ink on off-white paper, with details handwritten in pencil, blue ink and red ink. Three documents. Two are letters to Ivor Williams of the Powell Duffryn Ltd. Cardiff Office regarding the number of electrical units purchased from the South Wales Power Company. Also attached is a document with a list/table of the electrical units purchased from the South Wales Power Company by Powell Duffryn Ltd from March 1936 - December 1948. Loose within pink/peach card file with other documents relating to Middle Duffryn and Bargoed High Pressure Station.