There is a letter book / account book of 347 p., 1790-1856, containing 466 draft copies of his commercial and social correspondence with shipping agents in Great Britain, France, Spain, Portugal, Holland, Germany, China, Canada, as well as in the United States. The correspondence concerns Bell's business arrangements, the various cargos he shipped and their disposal, political affairs affecting the shipping trade, laws and treaties of various countries to be dealt with, taxes, embargoes, piracy, threats of war, and other pertinent events. A second account book of 84 p. (many are blank), 1787-1852, for the Ship Stephania and others contains ships' records for 1799 to 1828 and miscellaneous accounts up to 1857. There is a one volume carbon typescript (113 p.) of genealogical notes and reminiscences by Gordon Knox Bell (Regent of the University of the State of New York and grandson of Isaac Bell) and others, ca.1940. There is also an essay and lists of the residents of Greenwich Street (including the Bell and Rogers families) by Elizur Yale Smith with related correspondence, 1940.

Correspondence, manuscripts of poems, and manuscripts of lectures by Benjamin. The correspondence consists of original letters of Benjamin, typescript and photostatic copies of Benjamin letters in other libraries, and letters to Benjamin from some of his literary contemporaries including Paul Hamilton Hayne, Willis Gaylord Clark, John Lothrop Motley, and Fitz-Greene Halleck. Many of the letters relate to Park Benjamin's lecture tours. There are other family letters and many documents relating to the Benjamin family,and two letterbooks of John Lothrop Motley. Also, a large amount of genealogical material of the Benjamin family, and its related families from the 16th century to the present day. There are also financial records, monographs, clippings, and photographs.

The Pierrepont family papers (1761-1918) document the intersection of commercial, civic and personal interests across three generations of one of the most prominent and influential families of nineteenth century Brooklyn, New York. The bulk of the collection concerns the business dealings of Henry Evelyn Pierrepont from 1838 to his death in 1888. This especially includes an extensive set of accounting and transactional records concerning the Pierrepont Stores, the family's warehouse on Brooklyn's East River waterfront; these include records of ships arriving at the Stores and their cargoes delivered. Additionally, there are substantive correspondence, legal documents and other materials concerning the Union Ferry Company, of which Henry was an officer. In addition to commerce and shipping, a major theme of the collection is that of land acquisition in Brooklyn Heights and at the adjacent waterfront in the early nineteenth century, and the development of that property over the course of the century. Included in the collection are correspondence, deeds, indentures, leases, accounting records, diaries, maps, invoices, receipts, business proposals, legal filings, clippings, and historical and genealogical manuscripts.

Correspondence, account books, invoices, insurance policies, ledgers, payroll and wage records, receipts, and galley proofs. The records concern his cotton spinning mills in Stockport and Mellor. There are letters from merchants, tradesmen, manufacturers, and others relating to textile manufacturing and its mechanization in England during the last quarter of the eighteenth century. Included among the correspondents are: Sir Richard Arkwright, inventor of the spinning jenny; his son, Richard Arkwright; Henry Norris; Samuel Oldknow; Thomas Oldknow; Richard and Susannah Pennant (Baron and Baroness Penrhyn); Samuel Salte; and William Salte. Also included are the galley proofs for those letters published in George Unwin: SAMUEL OLDKNOW AND THE ARKWRIGHTS (London, 1924)