One of the oldest houses in Philadelphia, Wyck is now a non-profit museum listed on the National Register of Historic Places. Nine generations of the Jansen-Wistar-Haines family owned the Wyck property from 1690 until 1973. The last family owner deeded 2.5 acres of land, the house and its contents, several outbuildings, a landscaped garden, and a small endowment to the Wyck Charitable Trust. The Wyck Charitable Trust and the Wyck Association now administer the preservation of the property and its educational services to the public. This collection contains diaries, letters, accounts, bills and receipts, deeds, and photographs. The collection as a whole is deepest for the period 1770-1970. Items of particular note include accounts of household expenses at Wyck from ca. 1790-1970; papers pertaining to the Academy of Natural Sciences of Philadelphia, Quaker schools, and social reform groups; agricultural and horticultural practices; and correspondence to and from cultural leaders of 18th and 19th century Philadelphia. The papers of the John S. Haines family (Ms. Coll. 52A) form part of the Wyck Papers. The papers cover the years 1845 to 1949 and are arranged into eight series.

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.).