Series IV. Sixth Generation Business and Personal Papers, 1753-1868, contain business papers, legal papers, and personal papers of Colonel Timothy Pickering's sons, John(6) (1777-1846), Henry (1781-1838), George (1789-1826), and Octavius (1791-1868), and his nephew Pickering Dodge (1718-1833). John Pickering(6) was a noted lawyer and scholar. The business papers in Box 13 pertain largely to his early law practice in Salem, his service in several sessions of the General Court, and his time as city solicitor in Boston. The papers in Boxes 14-17 contain legal briefs and Pickering's notes on particular cases. Many briefs concern property ownership, wills and estate settlements, or disputed insurance claims or other financial obligations. Other documents and notes deal with vessels or cargoes lost at sea, a petition to build a free bridge (Warren Bridge) from Boston to Charlestown (B14 F6), and construction of the Eastern Railroad (B16 F5-F6). Notable legal cases include Lord Stirling's claim to lands in Maine (B14 F7) and the insurance claim following the loss of the brig Oscar near Havana in 1832 (B15 F8-9 and B16 F1).

John(6) Pickering was esteemed as a linguist and philologist. Papers in Box 18, Folders 3-5 concern the Greek lexicon he wrote in 1826, the first with definitions in English and not Latin. Pickering also wrote various works on American Indian languages (B18 F6). His personal papers also include remarks on military law, the benefits of a classical education and an address as President of the American Academy of Arts and Sciences (F9) in 1845.

John(6) Pickering and his father Timothy Pickering corresponded frequently with one another. There are typescripts of 157 letters from John to his father in Box 19, Folders 2-3. About half the letters relate to the time when John Pickering was in Lisbon and London (1797-1801) preparing for his future life in politics and law. Following his return to Salem in 1801, Pickering's letters deal largely with political and legislative issues, both at the local and national level. Also present is correspondence from his ward (and relative) John C. Lee, two memo books, five bankbooks, and a plan of Sewall's estate in Salem (circa 1753).

Box 20 contains assorted printed materials including documents from the General Court and Supreme Court of the Commonwealth of Massachusetts, studies of American Indian and other languages, descriptions of Pickering's Greek lexicon, plans of railroad routes, announcements of exhibitions and other entertainments in Boston, and papers from historical and other societies, as well as many other items. Boxes 20 and 21 include newspaper clippings reflecting John Pickering's broad interests in law, politics, history, and language. Three oversize scrapbooks, totaling about 270 pages, contain documents pertaining to Pickering's years as City Solicitor for Boston, as well as miscellaneous papers. The legal documents include extensive coverage of the Boston and Providence Railroad v. the City of Boston case (1843-1844), while the miscellaneous papers include business papers, invitations, essays, and excerpts from Roger Williams's Indian language vocabulary, among many items.

Henry Pickering (1781-1838), Timothy's third son, was a businessman in Salem. This collection contains letters from Henry to his father Timothy, his mother Rebecca, and his sister Mary. The letters to his father deal primarily with Henry's early financial success and offers to assist his family, and then with his later financial failure. Letters to Rebecca and Mary describe Henry's life in New York City and in upstate New York along the Hudson River. Of particular interest is a letter to Mary describing Timothy's death (1829) and an ode to Mary's twins Mary and Elizabeth, who were born on the day Timothy died. Included with Mary's letters are two from Henry to her husband, Benjamin Ropes Nichols, and one from Nichols to Henry. Also present is a letter from Henry's uncle Paine Wingate, memorials to Henry's mother Rebecca, and an account of a shipping loss.

George Pickering (1789-1826), seventh son of Timothy Pickering, led a short and unfortunate life. Afflicted with mental illness, the papers in Box 22, Folder 7 document his admission to the Asylum for the Insane in Charlestown, Massachusetts in 1821.

Octavius Pickering (1791-1868), eighth and youngest son of Timothy Pickering, was a lawyer and reporter. Notes, correspondence and drafts for his biography, The Life of Timothy Pickering, can be found in this collection. Octavius completed the first volume before his death in 1868, and his friend Charles Wentworth Upham completed the task in 1873.

Pickering Dodge (1778-1833), Timothy Pickering's nephew, was a successful merchant in Salem. He is represented in this collection by an account of the settlement for the loss and charges of the brig Alert in 1798.