On the Influence of Trades, Professions and Occupations in the United States in the Production of Disease. By Benjamin W. McCready, M.D. With an Introductory Essay by Genevieve Miller. [Publications of the Institute of the History of Medicine, The Johns Hopkins University, Fourth Series, Biblioteca Medica Americana, Vol. IV.] Baltimore: The Johns Hopkins Press, 1943. Pp. 129.