Abstract :
A memorial tablet marking the site at which Elihu Thomson (A´84, F´13, HM´28) built his first bipolar dynamo for generating alternating current was unveiled in Philadelphia, Pa., January 3, 1940. Placed on the office building now occupying the site of the Harrison Machine Works where Thomson worked on inventions in 1878–79, the tablet was erected under sponsorship of the Franklin Institute and through the efforts of four of Thomson´s early associates, A. L. Rohrer (A´87, M´88), J. R. Lovejoy (A´91, F´13), H. G. Reist (A´90, F´13), and W. J. Foster (A´07, F´16).