For a thorough discussion of the matching portraits of John and Abigail Adams reproduced in this volume, see Henry Wilder Foote, “Benjamin Blyth, of Salem: Eighteenth-Century Artist,” Proceedings of the Massachusetts Historical Society, 71 (1953–1957): 64–107, especially p. 64–71, 81–82. See also a note under Adams’ Diary entry of [6 or 13] August 1766 at p. 318.