The Josiah Fox papers include professional, personal, and family papers concerning the naval architect and shipbuilder and also contain a series of transcripts of some of the original papers as they were compiled by their collectors, Ernenst J. Wessen and Merle T. Westlake. The bulk of the collection related to Fox's work as a naval architect, shipbuilder, and naval administrator from 1795 to 1809. The collection has been divided into four series.

Series I. Naval Architecture and Shipbuilding Papers includes ships' papers, correspondence, specifications, accounts, drawings, and writings by Fox and others. This series has been divided into three subseries. Subseries A. Ships' Papers and Correspondence includes materials related to specific ships and related correspondence. The ships' papers are comprised of materials concerning the design or construction of a single identified vessel. The papers relative to the frigates Chesapeake, Congress, Essex, President, and United States are the most complete. The inventory of the frigate Raleigh is notable for its detailed description of one of the earliest American ships. The correspondence in this subseries includes incoming and outgoing letters regarding the design and construction of vessels, administration of the naval yards at Gosport, Virginia and Washington, D. C., and appointments to positions in the War Department and later to the Navy Department. There are a number of letters from the Secretary of the Navy, Ben Stoddart, and other significant naval administrators and officers such as Joshua Humphries, William Pennock, and Thomas Tingey. Of particular interest is the autograph letter from Paul Revere to General Henry Jackson with Revere's estimates of the copper and tin work for the USS Constitution (June 18, 1796). Two letters from William Hall to Fox (June 23 and 27, 1807) contain a detailed account of the battle between the USS Chesapeake and the HMS Leopard and of events in Norfolk after the confrontation. There are photocopies and transcripts integrated into the correspondence of this series. It is not clear who did this or when the copies and transcripts were created.

The letter books in this collection are almost entirely comprised of correspondence concerning naval affairs. The first volume contains incoming correspondence and an index. Volumes two and three are outgoing correspondence with some memoranda concerning specifications and dimensions of various naval vessels. These two volumes are also indexed. Volume four is outgoing correspondence with similar memoranda but is not indexed. There are also folders with that contain memoranda and notes on dimensions and specifications for warships of a designated class. Similar material relating to more than one vessel or vessels of an unidentified class is located in the Miscellaneous Specifications folder. Within the specifications for a 36-gun ship are photocopies obtained from the Department of the Navy.

Subseries B. Naval Yards contains material related to specific naval yards that Fox worked for. The Gosport Navy Yard materials folder contains papers regarding supplies of timber, metal products, etc. specifically associated with activities at Gosport. Of interest among the miscellaneous papers is a petition from the laborers for a pay raise, estimates for the construction or repair of docks, and a list of regulations in force at the yard. The Washington Navy Yard papers contain similar materials related papers, lists of employees (some including rates of pay), cost estimates for physical improvements, and a list of yard regulations.

Subseries C. Other includes miscellaneous naval architecture and shipbuilding papers. The naval architecture literature folder contains manuscript copies of writing by other individuals, including a description of "a work to be published in 1805," The Elements and Practice of Naval Architecture. Miscellaneous materials include papers on timber and metal products needed for an unspecified ship at an unspecified yard. Miscellaneous writings include a list of "Ships of War drafted by J. Fox - for the United States (1799)," a draft memorandum regarding the Fox/Humphries controversy, the associated article from Niles Register (1827), and a holograph autobiographical statement written for the Secretary of the Navy in 1813. Of particular interest in the printed matter folder is a 1797 broadside entitled "Regulation Respecting Salutes," a report on coastal fortifications (1806), prints of various ornate figureheads, and stern configurations. The folder labeled "File dividers" contains thin slats of balsa wood that Fox apparently used to manage his correspondence.

Series II. Personal and Business Papers includes correspondence, account books, legal papers, and printed matter. The correspondence is comprised of incoming and outgoing letters, mostly those received from family members. Most of the family correspondence related to the business activities and personal affairs of a number of relations in England and America. Frederick Beates managed Fox's business affairs in Philadelphia, and so his correspondence is largely concerned with investments. Of interest in the legal papers is Josiah's document of certification as a shipwright in England. Other legal papers document purchases of slaves and their manumission by Fox. The printed matter is almost exclusively comprised of biographical news clippings on Josiah Fox.

Series III. Family Papers are composed of miscellaneous deeds, accounts, and letters relating to a series of Fox's relations and ancestors. The Anna (Miller) Fox correspondence received is mostly from Josiah and is generally personal in nature. The genealogical notes were taken by mostly unidentified individuals, and were used in the compilation of the genealogical chart (See Appendix I).

Series IV. Transcripts and Reproductions contains documentation of the two major accessions of Fox papers as they were maintained by their collectors. The MSS calendar for the Wessen collection includes detailed descriptions of the contents of letters and letter books collected by Wessen. It also includes a discussion of sources available on the history of the American Federal-era Navy and a commentary of the Fox/Humphries controversy. There are four separate MSS calendars; they are the same except for some minor differences. The MSS transcripts have been left in the numerical order that Wessen maintained, so that citations to Wessen's MSS numbers can be traced using the transcripts. The "S" numbers at the end refer to "supplement" manuscript numbers utilized by Wessen to add material to his collection after the initial arrangement had been completed. Materials from the Merle T. Westlake collection include a microfilm copy of the papers and a bound transcript of the collection with provenance information in the introduction.