Letters (including some transcripts and photostats) from and to Vaughan from many American and British correspondents, including: Also personal correspondence and business papers of Benjamin, Charles, Petty, Samuel Sr., Samuel Jr., William, William Oliver, and Sarah Vaughan (2 boxes); lectures, mostly in shorthand (3 vols.); a large number of notes and memoranda on a wide variety of topics, such as agriculture, architecture, astronomy, diplomacy, diseases, dueling, electricity, hieroglyphs, internal improvements, medicine, meteorology, land, manufactures, politics, punctuation, religion, silk-manufacturing, stock-breeding, taxation, Unitarianism, Benjamin Franklin, John Locke, Napoleon I, Joseph Priestley, Bowdoin College, town of Hallowell, Maine; notes on the peace negotiations, 1782-1783; miscellaneous legal papers; genealogy of the Abbott-Vaughan families. For a personal account of the collection, see Mrs. Mary Vaughan Marvin, "The Benjamin Vaughan Papers," APS Proceedings 95 (1951): 246-249.

Personal and professional correspondence of the chemist Robert Hare, including drafts of letters to editors of journals on such varied topics as fish guano, slaughterhouses, paper money, and the meaning of the term "Yankee annexations." The collection originally contained over 300 scrolls, since disbound, which contained drafts of letters, essays, and lectures, composed by Hare on ordinary sheets of paper, then pasted end to end, and rolled up. The essay and lecture topics include: chemistry, storms, slavery, currency, fire-fighting, capital punishment, railroads, the Smithsonian Institution, Michael Faraday, religion and Spiritualism, riots in Philadelphia, epidemics, underwater blasting, and Ralph W. Emerson; there is some verse. The collection also contains an account book of Hare and his wife, 1806-1829 (180 pp.; B/H22#3); a volume by Hare on Cyclones (tornadoes), n.d. (ca. 60 pp.; B/H22#4); and Samuel Powel, Jr.'s "Short notes on a course of antiquities at Rome... under M. Byre Antiquarian," 1764. (60 pp.).

A product of the distinctive culture of reform in antebellum Philadelphia, William Parker Foulke was the scion of the old elite who put a conservative stamp on social change. Trained as an attorney, Foulke spent much of his adult life engaging his deep amateur interest in natural history and mental philosophy and devoting himself to a variety of civic and philanthropic causes, including the colonization of formerly enslaved persons, penal reform, and cultural institutions in his native Philadelphia. The Foulke Papers are the product of the diverse social and intellectual interests of the Philadelphia attorney and philanthropist William Parker Foulke. Consisting primarily of correspondence, notes, and essays, the collection touches on Foulke's many interests. The collection includes numerous lectures delivered by Foulke along with material on the Lancaster County Prison, New York Prison Association, and the Philadelphia Society For Alleviating the Miseries of Public Prisons; notebooks concerning prisons and prisoners, including a 1846-1852 diary, and a listing of prisoners, their race, age, crime, sentence, and observations; a diary concerning the American Colonization Society (1852); a copy of an arctic diary (1853-1854) by John Wall Wilson, in the hand of Isaac Israel Hayes, which recounts much of the journey aboard the brig Advance, commanded by Elisha Kent Kane. There is also a list of buildings (1820-1841) designed by John Haviland, and material on the American Academy of Music, Philadelphia.