Founded in 1743 by Benjamin Franklin, the American Philosophical Society was the first learned society in the United States. For over 250 years, the Society has played an important role in American cultural and intellectual life. Until the mid-nineteenth century, the Society fulfilled the role of a national academy of science, national library and museum, and even patent office. Early members of the Society included Thomas Jefferson, David Rittenhouse, Benjamin Rush, Stephen Peter Du Ponceau, George Washington, and many other figures prominent in American history. The Archives of the American Philosophical Society consists of 192.25 linear feet of material, organized into thirteen record groups dating back to 1743. The Society's archives extensively documents not only the organization's historical development but also its role in American history and the history of science and technology.

Britton Chance (1913-2010) was a biochemist and biophysicist as well as a pioneer in the field of biomedical optics. Chance received his Ph.D. in Physical Chemistry from the University of Pennsylvania in 1940 and his Ph.D. in Biology and Physiology from Cambridge University in 1942. Over the course of his nearly eight decade career, Chance was dedicated to the application and transfer of basic scientific research and technology to clinical medicine. The Britton Chance Papers contain correspondence, research notes, experimental data, publication materials, and photographs stemming from Chance's life as a biochemist, biophysicist, and yachtsman. The collection is broken up into fifteen series that document every aspect of his scientific work.

Though the Miscellaneous Manuscripts collection is composed of items that do not fall readily into any other existing collection, the two dominant intellectual areas represented in the collection are Early American History and History of Science.