The Kopp mss., 1955-1958, consists of correspondence and memorabilia relating to author Sylvia Plath's time at Cambridge, collected by her friend Jane Kopp.
The Muller mss., 1910-1967, consists of the papers of Hermann Joseph Muller, 1890-1967, geneticist and Nobel prize laureate, including correspondence; writings and reprints; research and data from his work as well as from his students and colleagues; materials related to conferences; and work with various professional organizations.
The Muller, Herbert, mss., 1913-1976, consist of the correspondence, writings and lecture notes of Herbert Joseph Muller, 1905-1980, distinguished professor literature and government at Indiana University, Bloomington.
The Gwatkin mss., 1773-1780, consists of letters from educators Sarah More, 1743-1817, and Martha More, 1750-1819, to their patron, heiress Ann Lovell Gwatkin, 1729-1809.
The Meier mss., 1927-2010, consists of the correspondence and papers of education reformer Deborah W. Meier (1931-), who is frequently credited with founding the modern small schools movement in the United States.
The Leavitt mss., 1846-1849, consist of six letters from George C. Leavitt, 1824-1854, teacher and surveyor, to his parents in New Hampshire, and one letter from his wife Elizabeth to his parents.