This series consists of correspondence amongst Cowper's circle of family, friends, editors, and others, as well as a few assorted manuscripts. While the majority of the letters are original, there are also some copies. The primary correspondents include Sir John Carr, William Hayley, Lady Hesketh, John Johnson, John Newton, and Samuel Teedon. This series is first organized alphabetically by correspondent, then alphabetically by recipient, and finally chronologically by date. Unidentified manuscripts are located at the end of the series.