Medicine--Practice--20th Century Academy of Natural Sciences--Philadelphia (Pa.) 1 Episcopal Hospital--20th century 1 Health and hygiene 1 Medical Profession--Surgery--Pennsylvania--20th century 1 Public Health and Hygiene--Early 20th Century 1 Tuberculosis Research--Early 20th Century 1 more ... University of Pennsylvania--Department of Hygiene--Early 20th Century 1 less ...