The collection contains correspondence between John Newton, clergyman and hymn writer ("Amazing Grace"), and John Campbell, philanthropist, author, and traveller. Portions of the letters were published by Campbell in "Letters and conversational remarks, by the late Rev. John Newton, rector of St. Mary Woolnoth, Lombard-street, London: during the last eighteen years of his life." The collection contains 36 letters written by John Newton to John Campbell and copies of seven letters from Newton to recipients other than Campbell. All letters date between 1789 and 1802.