12/20/1880 Girdler, Charles A to Edison, Thomas Alva
Electric traction; Ore milling and separation [Marginalia by Edison, Thomas Alva]
[D8004]  Document File Series -- 1880: (D-80-04) Edison, T.A. -- General
[D8004ZGX; TAEM 53:274]
Courtesy of Thomas Edison National Historical Park.