“Illiteracy… compromised but did not preclude participation in America’s [antebellum] postal network.
“A fascinating correspondence between absentee slaveholder William S. Pettigrew and the enslaved foremen on his two North Carolina plantations illustrates this crucial point nicely. During an an extended convalescence at Healing Springs in Virginia, Pettigrew sought to manage his business affairs by corresponding with Moses and Henry, the two illiterate overseers, relying upon a white intermediary.
” ‘Thinking you would be glad to hear from me,’ Pettigrew wrote to Moses in 1856, ”I have concluded to write you a few lines and will enclose them to Mr. White who will read them to you.’ Though Malica J. White’s own skills were quite rough, he dutifully transcribed the replies of three different slaves, and a detailed correspondence ensued, dealing with countless details of crop production, workplace discipline, and plantation life. Pettigrew always addressed Moses and Henry directly, and they responded in kind. Upon receiving their replies, Pettigrew offered paternalistic congratulations to Moses for his ‘succe[ss] as a letter-writer,’ proudly showed the letter to a friend, and instructed Moses to ‘writ[e] more frequently,’ de-emphasizing White’s mediation’ ….”
— From “The Postal Age: The Emergence of Modern Communications in Nineteenth-Century America” by David M. Henkin (2008)