Starting in the early nineteenth century, residents of Wyck collected genealogical information about their ancestors, particularly in regard to the Bowne, Haines, and Wistar families. Included in the collection is genealogical research done by Reuben Haines III primarily on the Haines family in the first decades of the nineteenth century. Later in the nineteenth and twentieth centuries, Jane Reuben Haines, Caspar Wistar Haines II, Jane Bowne Haines II, and Reuben Cope Haines conducted extensive research on the three previously mentioned families as well as on more distant relations in the Hartshorne, Johnson, Lukens, Marshall, and other families. Further genealogical information may be found in the correspondence of Reuben Haines III, Jane Reuben Haines, Caspar Wistar Haines II, Jane Bowne Haines II, and Reuben Cope Haines.

The correspondence, dating from 1676-1971, is the most extensive series in the Wyck Papers. It includes the letters of family members, as well as correspondence to and from notable people as listed in this Register. The correspondence particularly illustrates the internal development of this family, the development of American thought and society, and the relationship between family and society. The emphases on religion, education, and concern for Blacks are topics which exemplify this dynamic. These issues emerge in the correspondence of Caspar Wistar Haines I, Hannah Marshall Haines, Reuben Haines III, Jane Bowne Haines I, Robert Bowne Haines I, and Caspar Wistar Haines II.

Letters not associated with a family member include a collection of correspondence from Anthony Morris to his children from 1790 to 1816.

This series includes diaries, essays, journals, notebooks, and poetry which reflect the characters, lifestyles, interests, and thoughts of the various authors. The earliest manuscript is an oath of allegiance signed by Caspar Wistar in 1721, and the latest is a typescript of a book about Wyck written in 1970.

Of note are the diaries kept by Reuben Haines III, Margaret Vaux Wistar Haines, and Caspar Wistar Haines II, the latter two of whom kept personal journals for over 65 years. Also of interest are a variety of notebooks kept by many family members on topics ranging from agriculture to horticulture, beer brewing, natural science, travels in the U. S. and abroad, patent inventions, and religion. Children's cypher books offer insight into early American educational practices, notably at the Quaker boarding school, Westtown; and testimonies to deceased persons provide biographical information about many of the family members represented in this collection.

A variety of miscellaneous writings includes such highlights as the Memoirs of the French Count de Miollis; a series of papers describing the exploits of a runaway slave, Henry Hudson, in 1819; and Notes prescribing methods for cleaning the rooms of yellow fever victims.

The Financial Material includes business and household accounts, bills and receipts, bank books and statements, and tax information which together present a remarkably complete record of the family's financial history. Certain of these materials document the purchase of food, clothing, and many of the furnishings still in the house; the employment of servants; and various improvements made to family properties. Also of interest are the records of family businesses, including two brewhouses (c.1790-1850), a lumber company (1911-1915), and an orchard (c.1940-1963).

This series contains information regarding the transfer of family wealth from one generation to another. Also included are those Financial Materials (receipts, accounts, banking, etc.) accumulated during the settlement of family estates. Some estates continued for decades, and both daily and business expenses for the duration are found within this series. For example, the Estate of Reuben Haines I (d.1793) contains many of the expenses incurred by his Philadelphia brewhouse during the early 19th century; the Estate of Caspar Wistar Haines I (d.1801) contains many of the expenses of Hannah Marshall Haines until her death in 1828; the Estate of Reuben Haines III (d.1831) contains virtually all of the expenses of Jane Reuben Haines until 1888; and the Estates of Catherine Haines Hartshorne, Caspar Wistar Haines I, and Reuben Haines III include many of the expenses of Ann Haines during her lifetime. This series, then, is an important adjunct to Series IV, Financial Materials.

Included in Legal Materials are bonds, contracts, deeds, leases, mortgages, and promissory notes. The significance of these papers lies chiefly in their information about land ownership within the family.

The legal documents regarding real estate reveal a major source of long-term wealth of the Haines family. Reuben Haines I speculated in real estate with considerable success during the second half of the eighteenth century. Besides valuable land holdings in Philadelphia, he purchased huge tracts in northern and central Pennsylvania which his descendants inherited and variously rented or sold for cash profits.

The documents concerning the family's Philadelphia and Germantown properties are of interest for information on 18th and 19th century land divisions, notably on Second, Fourth, and Market Streets in Philadelphia, and on Germantown Avenue, Walnut Lane, Haines Street, and High Street in Germantown.

Finally, this series as a whole furnishes examples of the style and format of legal materials over a period of 250 years.

Memorabilia includes a wide variety of materials, such as announcements, diplomas, membership cards, mementos, and programs. Many items in this series are of interest because of their age or rarity, such as early charge account tokens, passports, and valentines.

This series contains printed material collected by the family and reveals business, educational, and religious interests. Most of this material dates to the 20th century.

This series provides a graphic complement to the manuscripts in the collection. Included are prints, original art, photographs, and maps.

Of interest among the prints are miscellaneous late 18th and early 19th century engravings, including a view of Wakefield Mills, Germantown. Family interest in natural history is reflected in prints of animals and plants. Also notable are prints of the homes of Charles Bonaparte and E. I. Dupont, and of homes in the Philadelphia area.

The photographs provide documentation of Wyck's interior and exterior appearance from 1871 through 1958. This section also includes photographs of family members who lived after photography became popular. Representations of many family members who lived before the invention of photography are provided in photographs of portraits. A collection of stereoscopic views of the U. S. Centennial at Philadelphia is also contained in this category.

Maps and plans included in this series provide documentation of 18th and 19th century land divisions in Germantown and Philadelphia. Also included are plans of Wyck before and after its renovation in 1824.

This series is not a subject category of itself, as it is based on size rather than content. The materials are listed throughout the collection in the appropriate series.