Thomas Edison and Henry Ford looking at an Edison Telegraph at the Western Union Exhibit, Liberal Arts Palace, Panama-Pacific International Exposition, 1915; Courtesy Special Collections, University of California, Davis

Thomas Edison and Henry Ford looking at an Edison Telegraph at the Western Union Exhibit, Liberal Arts Palace, Panama-Pacific International Exposition, 1915; Courtesy Special Collections, University of California, Davis

Thomas Edison and Henry Ford looking at an Edison Telegraph at the Western Union Exhibit, Liberal Arts Palace, Panama-Pacific International Exposition, 1915; Courtesy Special Collections, University of California, Davis