History: Rediscovering William Stanley, Jr.—Part 1

William Stanley, Jr. pioneered the development and use of ac for electric light and power applications. He conceived solutions before others recognized the problems. He contributed in a major way to a major invention: the transformer, the key to large-scale exploitation of ac electricity. Prior to 1885, few people were interested in ac except as a way to circumvent problems with sparking commutators on rotating electric machines. In March 1886, Stanley demonstrated a system of single-phase ac for lighting applications in Great Barrington, Massachusetts, that changed the worldview of electricity. His system showcased the transformer that he had invented two years before. For the first time, this demonstration of long-distance, step-up/step-down, ac power transmission brought into public view the significant benefits offered by ac over dc. Stanley led the way as engineers worldwide extended power transmission to ever higher potentials and increasing distances. He also invented an inductor electric machine that was widely used as an alternator prior to 1900.