Harriet Verena Evans was born in Lancaster, Pa., on April 28, 1782, the daughter of John and Sarah Musser. On May 21, 1807, Harriet married Cadwalader Evans (1762-1841), a former surveyor who went on to a distinguished career in politics, as one of the directors of the Bank of the United States, a promoter of the Schuylkill Canal, and president of the Schuylkill Navigation Company. The couple had nine children, including a set of twins. The diary of Harriet Verena Evans is an unusual example of a woman's spiritual diary from early national Philadelphia. Beginning on her 46th birthday in 1827, the same day her seventeen year-old son John died, Evans made sporadic entries in her diary for seventeen years, marking birthdays, holidays, special events, and anniversaries of various kinds. Fixated upon praying (or fretting) over her spiritual state and future, Evans continued to mourn over John's loss for many years, remembering him regularly on the date of his birth, death, and burial. She was also particularly prone to composing (or copying) religious poetry, and in sections, the diary verges on a poetical commonplace book. Other entries reveal Evans' concern for her other children, three of whom were students at the University of Pennsylvania, and on July 25, 1832, she made a particularly long entry discussing the arrival of the cholera in Philadelphia.

This collection includes letters, diaries, notebooks, and early photographs, relating primarily to the Wister family of Germantown and Philadelphia. Much of the correspondence concerns domestic news and consists of letters from or to Sarah Wister. These include interesting observations on Germantown and Philadelphia society from other families as well, such as the Bayntons and Bullocks. There are numerous letters from various Wisters, including Casper, Charles Jones, Elizabeth (including a journal of a trip to Bristol, 1783), Hannah, John, Owen Jones, and others. There is also poetry by Sarah.

The collection contains information on Fox family speculation in western lands, two manuscript maps from the 1790's and 1830's depicting the family's holdings in northwestern Pennsylvania, and a photograph album from the 1890's documenting Chestnutwold, the Fox estate adjacent to Andalusia. Chief correspondents are Samuel and George Fox.

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.

A physician, natural historian, and professor at the University of Pennsylvania, Benjamin Smith Barton (1766-1815) was one of the central figures in Philadelphia's early national scientific establishment. Having received his medical training in European universities, Barton was appointed Professor at the University of Pennsylvania in 1789, lecturing on botany, materia medica, natural history. A prolific author, he established his reputation as one of the nation's preeminent botanists through his botanical text book The Elements of Botany (1803), but his contribtions to zoology, ethnology, and medicine were equally noteworthy. Barton's monograph on the "fascinating faculty" of the rattlesnake and his efforts in historical linguistics (New Views of the Origin of the Tribes and Nations of America, 1798) were widely read, and his Philadelphia Medical and Physical Journal (1804-1809) was one of the nation's first medical journals and an important outlet for natural historical research. The Barton Papers offer a comprehensive view of the professional work of Benjamin Smith Barton from the time of his return to the United States in 1789 until his death. The collection is divided into five series: Correspondence, Subject Files, Bound Volumes, Graphic Materials, and Printing Plates. The collection includes a particularly valuable series of botanical, medical, and natural historical drawings collected by Barton for research, reference, and publication. Among the many artists represented are William Bartram, Frederick Pursh, Pierre Turpin, and Benjamin Henry Latrobe.

After a brief career in the Congregational church, J. Peter Lesley (1819-1903) left the ministry in 1852 to work full-time as a geologist. Having gained experience in structural geology and stratigraphy with the First Pennsylvania Geological Survey (1836-1842), Lesley became an expert in the geology of coal, working for the Pennsylvania Railroad and other corporations and conducting some of the first systematic studies of the state's hydrocarbon resources. A long-time professor at the University of Pennsylvania, he was elected to the APS in 1856, serving variously as its librarian, secretary, and vice president, and he was selected as Director of the Second Pennsylvania Geological Survey (1875-1889). The Lesley Papers include letters to and from Peter Lesley and his wife, Susan on geology, coal and iron mining, abolition, educational reform, organized charity, and Unitarianism. The collection offers important insight into academic and applied geology in late 19th century Pennsylvania, the development of the coal and iron industries, as well as into the Lesleys' progressive social and intellectual milieu. It is divided into three series: Lesley's general correspondence, his correspondence with his brother Joseph, and microfilms of Lesley's research notes.