The Henry M. Seidel Collection covers his years as a medical student at Johns Hopkins. It consists of Seidel's class notes and several large binders of handwritten notes and handout materials from Johns Hopkins University School of Medicine lectures and Johns Hopkins Hospital grand rounds, 1943-1945. In addition to providing extensive written records of School of Medicine classes, the notebooks contain photographic records. The physiological chemistry class notebook includes dozens of black and white photographs taken of the instructor's blackboard notes. These photos capture the blackboard text that was heavily interlaced with graphic models of molecular structures, diagrams, chemical formulas, equations, tables, and graphs. The neurology class notebook contains numerous hand-colored photographs of sections of specimens. The notebook for the biostatistics class contains computer punch cards along with the hospital obstetrical code necessary for analysis. An extensive collection of Seidel correspondence while he was dean of the school of health services is found in the institutional records of the Office of the Dean, Johns Hopkins University School of Health Services. Also in the institutional collections are Seidel's records (while assistant dean of the school of medicine) of the Health Care Programs Working Committee of 1968, also known as the "Heyssel Committee."