These photostats of letters were collected from various repositories by Lyman H. Butterfield for his book, "Letters of Benjamin Rush" 2 v. American Philosophical Society Memoirs 30(1951). Some of the topics discussed are Philadelphia and United States politics, slavery, Afro-American churches, and medicine.

The Welsh non-conformist minister Richard Price (1723-1791) was a moral philosopher and political and economic theorist whose ideas leant support to the American cause during the Revolution. Of broad and liberal mind, he was an integral member of the intellectual coterie surrounding William Petty, the Earl of Shelburne, and was a founding member of the Unitarian Church. Befitting a latitudinarian thinker, the range of Richard Price's correspondence is extremely broad, touching upon his rationalistic philosophy and dissenting theology, his political views on British politics, America and the American Revolution, the Constitutional settlement, the future of the United States, social reform, demography, prisons, and slavery. The ninety letters in the collection are arranged chronologically, with correspondents including Charles Chauncy (8 letters, 1772-1779), Benjamin Franklin (7 letters, 1775-1789), John Howard (11 letters and a biographical manuscript, 1770-1789), Thomas Jefferson (3 letters, 1785-1789), Benjamin Rush (8 letters, 1786-1790), and Edward Wigglesworth (3 letters, 1775-1786), as well as lesser known figures such as the reformer John Howard.