Martha Lewis Trapp Priestley (1745-1828) was the youngest daughter of John and Mary Lewis, printers and booksellers in Bartholomew Close (1731-49) and at 1 Paternoster Row (1749-76). Martha was raised in the Moravian congregation in Fetter Lane, London, where her parents attended and where she would become a member in 1772.  In 1766 she married Henry Trapp (1740-91), one of her mother’s apprentices, having worked alongside him and her mother during her youth in the print shop in Paternoster Row.  Upon her husband’s death in 1791, Martha Trapp, just as her mother had done after the death of John Lewis in 1755, continued the family business at 1 Paternoster Row, although it seems likely, given her husband's alcoholism and bouts with insanity, she was most likely the primary operator of the business from the mid-1780s through 1791. In 1796, she turned the business over to her son-in-law, Vaughan Griffiths.  In 1794 she had remarried, this time to the Independent minister Timothy Priestley (1734-1814).

Martha Trapp appeared on some 7o imprints almost exclusively as “M. Trapp.” Of these works, eleven were by John Cennick, a continuation of her family’s dominance as sole printer and seller of his writings. As with John and Mary Lewis and Henry Trapp, Martha Trapp’s imprints were almost exclusively religious and evangelical. Among the dissenting ministers and lay-persons she printed or sold were George Best, George Burder, William Button, John Cottingham, Maria de Fleury, John Gill, Joseph Hart (continuing her family’s involvement with the sale of his Hymns), Robert Robinson, and Timothy Priestley, her future husband. Evangelicals from the Established Church included William Romaine (under whose ministry she sat for a time at St. Dunstan in the West), John Berridge, and James Stillingfleet, as well as the Moravian leader C. E. De Coetlogon. She worked with some fifty other sellers during these years, primarily dissenters, including three Baptist ministers who moonlighted as booksellers (William Button, Thomas Thomas, and James Upton) and the son of another Baptist minister (John Martin, Jr.). She also worked with three women (two of whom sold from their homes): the daughter of Joseph Hart, from her house at 58 Golden Lane, opposite Bond's Brewhouse; Elizabeth Newbery, from her shop at the corner of St. Paul's Church Yard and Ludgate Street; and Maria de Fleury, from her house at 31 Jewin Street. After her marriage, she continued to sell for about three more years, appearing on another 43 imprints, this time as “M. Priestley.” She was interred in Bunhill Fields on April 16, 1828, most likely next to her first husband, Henry Trapp.  For more on Martha Lewis Trapp Priestley, see Timothy Whelan, "Mary Lewis and her Family of Printers and Booksellers, 1 Paternoster Row 1749-1812" in Publishing History 85 (2021): 31-67. Research on Martha Trapp/Priestley is also being undertaken by Alison McNaught.