These are letters from Jeremy Belknap, Aaron Dexter, Ezra Stile, Samuel Vaughan, Jr., and others. There are also drafts of some of Cutler's letters.

Miscellaneous letters from and to Benjamin Smith Barton, Nicholas Collin, Henry Muhlenberg, Jeremy Belknap, Monsieur Le Roi, and a broadside by Robert Aitken. These letters concern botany and zoology in the U.S., England, and on the Continent, and mention contemporary figures as well as the American Philosophical Society.

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.