This collection consists of letters from doctors, relating to medicine and medical publications and editing, as well as medical organizations. Most significant of the correspondence is that with John Shaw Billings (ca. 60 letters).

The bacteriologist and virologist Thomas Milton Rivers spent over thirty years at the Rockefeller Institute as a researcher in the Department of Bacteriology and from 1937-1955, as Director. Working on measles and pneumonia, Rivers discovered the parainfluenzae bacillus and cultivated vaccine virus for human use, and during the 1950s, he played an important role in coordinating research on poliomyelitis as head of the National Institute for Infantile Paralysis. During the Second World War, Rivers led the Naval Medical Research Unit in the South Pacific, rising to the rank of Rear Admiral. The Rivers Papers contains correspondence, laboratory notes, speeches, and photographs documenting Rivers' activities at the Rockefeller Institute, the development of polio vaccine, and Rivers' Navy experience in the Pacific during World War II.

Simon Flexner, born in 1863, one of the nation's leading experts in pathology and bacteriology, was most renowned for his research on cerebrospinal meningitis, polio and infantile paralysis. Arguably though, Flexner's stewardship of the Rockefeller Institute was his greatest contribution to medical and scientific research. His rise in the medical community began in the late nineteenth century in Louisville, Kentucky, where despite not having completed even the seventh grade, Flexner taught himself basic bacteriology by conducting experiments at home using a microscope borrowed from the pharmacy where he served as an apprentice. Granted a medical degree from the University of Louisville School of Medicine in 1889, he went on to a pathology fellowship at the newly opened John Hopkins School of Medicine. Within two short years of leaving Louisville, Flexner received an assistant of pathology appointment at Johns Hopkins. It was a quick ascent and the beginning of a long and brilliant career that included a prestigious appointment at the University of Pennsylvania and then a directorship at the new Rockefeller Institute where he realized his lifelong dream of creating a dynamic and productive research laboratory. The Rockefeller Institute became instantly famous worldwide as the preeminent research facility for virology and under Flexner's direction produced invaluable contributions in pathology, bacteriology, and immunology. This collection does not reflect the early phases of Flexner's career at Johns Hopkins but does document an early interest in meningitis and other infectious diseases with science-related correspondence, laboratory notebooks, and administrative correspondence with the New York City and State Departments of Health. There is abundant material on Flexner's directorship of the Rockefeller Institute for Medical Research, including Flexner's search for staff, an involved process which is detailed in correspondence with the scientists, many of whom became quite famous. Also included is material relating to the other institutions and Rockefeller philanthropies with which Flexner was involved. (Among the most significant correspondence, however, may be that which documents the support of the General Education Board and the Rockefeller Foundation in the development and subsequent reorganization of medical schools following brother Abraham Flexner's scathing report on medical education in the United States and Canada). This collection would be of great interest to anyone interested in the history of bacteriology, histology, and immunology or the general history of modern medicine and philanthropy.

These papers reflect Isaac Hays' interests and activities in the medical profession and as an editor. His interest in paleontology, especially in the controversy with G. W. Featherstonhaugh, is also represented. There is one separate volume (77 letters) containing correspondence about natural history and naturalists, written to Hays by C. L. Bonaparte, George Ord, Thomas Say, and Charles A. Lesueur. The correspondence in the larger collection, however, contains much material on the American Journal of the Medical Sciences, particularly illuminated in the correspondence with John D. Godman. The I. Minis Hays material consists of letters from doctors, relating to medicine and medical publications and editing, as well as medical organizations. Most significant of the correspondence is that with John Shaw Billings (ca. 60 letters).

Correspondence, notebooks, research data related to Cole's career as the first director at the Hospital of the Rockefeller Institute of Medical Research, 1908-1937. His research of pneumonia was conducted when the disease was epidemic. Personal correspondence reflect Cole's life as a medical resident at Johns Hopkins, 1899-1908. Documented are his memberships in leading medical organizations throughout his career, including the Association of American Physicians and the New York Academy of Medicine. This collection showcases the evolving changes in the medical profession from practicing physician to clinician.

A pathologist and cancer specialist, James B. Murphy (1884-1950) spent most of career associated with the Rockefeller Institute (1911-1950) investigating the role of lymphocytes in tuberculosis, x-ray mutagenesis, and the nature of malignant tumors in fowls. The Murphy Papers contains professional correspondence and research notes relating to James B. Murphy's cancer research at the Rockefeller, and information on several of the organizations to which he contributed or belonged, including the American Association for Cancer Research; American Bureau for Medical Aid to China; American Cancer Society; Bar Harbor Medical and Surgical Hospital; Roscoe B. Jackson Memorial Laboratory; Memorial Hospital for the Treatment of Cancer (New York City, ca. 1932-1950); National Advisory Cancer Council; and the New York Academy of Medicine (1923-1950). Murphy helped to develop mobile laboratories for hospitals in France during World War I.