Crossed-coil power-factor meters

P. A. Borden (The Bristol Company, Waterbury, Conn.): To one who has read the literature on power-factor measurement as published during the past 30 years, it would seem almost imposible that any further contribution of value could be produced. Mr. Millar, however, appears to have accomplished the task and made a valuable addition to the theoretical discussion of the subject, and particularly to the laws underlying scale conformation.