Created by the German priest Johann Martin Schleyer in 1879, Volapük ("World's Speech") was the first artificial language to gain wide spread popularity as a prospective form of universal communication. During the 1880s, Volapük clubs were formed throughout Europe and the Americas, with a particularly active center in eastern Massachussetts, however it was gradually replaced by its somewhat less elaborate rival, Esperanto. The Volapük Collection includes printed materials, ephemera, and small number of letters and postcards written in Volapük. Assembled by F. L. Hutchins of Worcester, Mass., a leading American Volapükist, the collection reflects the brief, but intense international interest in the potential of Volapük to become a lingua franca of business and a medium for exchange across borders, and it conveys some of the excitement its adherents felt at its potential.

This collection was assembled by Court and was partly used in the book, "The History of the Microscope" (with Reginald S. Clay, London, 1932). There is historical correspondence (including some by Court), documents, broadsides, and photographs, concerning microscopes and instruments. This includes material on Joseph Bonomi, James Epps, John Lee, Edward Nairne, and others. There is significant material on Cornelius Varley: account book, autobiographical sketch, watercolors and sketches, etc. This collection also contains a large number of deeds pertaining to the property of John Lee (1783-1866), Fellow of the Royal Society and an amateur astronomer. In addition, there are about 300 pamphlets, including early trade and auction catalogs, used by Court for his research.

These papers include letters, broadsides, and other documents pertaining to various branches of the Rittenhouse family, in particular, David Rittenhouse and his daughter Elizabeth "Betsey" Rittenhouse Sergeant. Included are references to Benjamin Smith Barton, and copies of documents concerning the Barton family, especially Thomas Barton, in Fanny Abbott's, "Family Records."

The papers include: minutes, 1794, 1802-1942; minutes of the Managing Committee and Committee of Seven, 1791-1950; rough minutes of the Managing Committee, 1819-1857; minutes of the Wardens, 1769-1919 (with some gaps); roll of members, 1841-1875; price books, 1786, ca. 1804, 1827, 1852; Price Book Committee minutes, 1786-1791, 1827-1897; price book of the Second Carpenters' Company, 1784; cash books, 1889-1952; treasurer's account, 1874-1907; ledgers, 1801-1896; record of certificates granted to measurers of carpenters' work, 1827-1889; account book, 1763-1834; minutes of the Building Committee, 1810 11; minutes of the Committee on fitting up the Old Hall, 1857; minutes of the Committees of Accounts and Rents, 1780-1784; minutes of the Library Committee, 1853-1889; receipts for books and library record of borrowers, 1846-1890; by-laws and rules and regulations and standing resolutions, ca. 1866-1869; minutes of the Friendship Carpenters' Company, 1770-1775; account of the Friendship Carpenters' Company, 1769-1799; rules and regulations of the Friendship Carpenters' Company and specifications for building, 1769; relief given to 12 widows, 1818; scrapbook, 1887-1892; Antiques, Curiosities, and Memorabilia, 1683-1855; autographs, pictures, etc., relating to the Centennial Anniversary, 1874; Trustees' minute book, 1895 1941; book of "Dementtions" of carpenter's work by Samuel Jones, 1784; real estate record, 1905-1918; receipt books, 1795-1918; and other materials. The whole collection has been filmed by APS. Recent deposits include: Miscellaneous bills, and bills and receipts relating to widows relief (1800-1854), Managing Committee minutes (1857, 1859, 1860), library bills (1795-1854). There are also more contemporary records on deposit (1952-1980s), relating to all aspects of the Company's activities (with restrictions on the use of some of this material).

David Rittenhouse (1732-1796) was one of the most prominent American men of science of the 18th Century. A skilled instrument maker, Rittenhouse was the an astronomer, playing a major role in recording the 1769 Transit of Venus, among many accomplishments. Rittenhouse also conducted important survey work for the state of Pennsylvania, establishing the state's western border, as well as overseeing the completion of the Mason-Dixon survey. In addition to his scientific endeavors, Rittenhouse's work for American independence places him among the important founding fathers. Subordinating his scientific interests for the greater good of Pennsylvania during the American Revolution, Rittenhouse served as a member of both the Pennsylvania Assembly and the Pennsylvania Constitutional Convention, and held powerful positions on the Pennsylvania Council of Safety and the subsequent Committee on Safety. Rittenhouse also served as the first director of the United States' Mint, at the behest of President George Washington. Rittenhouse was elected to the American Philosophical Society in 1768 and played a major role in placing the Society on the scientific map. He held many positions in the Society, including serving as its President from 1791 until his death in 1796. The Rittenhouse papers span 1774 to 1932, and consist of 61 items, over 0.25 linear feet. The collection is comprised mainly of correspondence, but also includes receipts, genealogies and broadsides.

From the Sugar Act of 1764 through the Tea Act of 1773, the British Parliament imposed a variety of taxes upon their American colonies in an effort to raise revenue to offset the enormous debts incurred during the Seven Years' (French and Indian) War. Far more efficiently than raising revenue, these duties raised the indignation of the colonits, contributing more than their share to the alienation that fueled the independence movement The two volumes that comprise the Pennsylvania Stamp Act and Non-Importation Resolutions Collection contain 34 manuscript and printed items relating to the political crisis over taxation on goods imported into the American colonies between 1765 and 1773, with a focus on Philadelphia. The first volume is concerned exclusively with agitation over the Stamp Act of 1765 and its repeal, while the second volume relates more specifically to the Non-Importation agreements of the 1760s, the Townshend Duties, and the Tea Act of 1773. Among these are letters of Governor John Penn, correspondence between the Sons of Liberty at Philadelphia and those of New York, 1766, an address of the committee of Boston merchants to a committee of Philadelphia merchants, 11 August 1768. Among the more dramatic letters are those from John Hughes, the would-be Stamp Officer for Pennsylvania who resigned bis commission in the face of public protest, and a seies of threatening letters addressed to James and Drinker, consignees for the sale of tea in Pennsylvania in 1773.