The distinguished physicians featured in this volume were all members of the American Philosphical Society (APS), the oldest learned society in America. The biographical memoirs, selected from the archives of the Society, present a panorama in the evolution of medicine during the 18th, 19th and early 20th centuries and the personalities behind them. The memoirs were selected and edited by APS members Clyde F. Barker, President, APS, Former John Rhea Burton Professor and Chairman, Donald Guthrie Professor, Dept. of Surgery, Hospital of the University of Pennsylvania; and Thomas E. Starzl, Professor of Surgery, University of Pittsburgh School of Medicine. Each memoir includes a portrait of the physician.