These are eighteen letters that mostly concern Indian linguistics. Regarding Zeisberger's Onondaga grammar and dictionary; Heckewelder's writings on the Indians; publications; question of whether or not any of the Lenape can pronounce the letter "r."

These forty-five letters concern legal and political matters, Indian languages and linguistics, philological matters, and the American Philosophical Society.

These papers include correspondence, legal documents, financial records, family material, maps and plats, pictures, printed materials, diaires, and journals of geological expeditions. Also included are undated materials.

These materials are comprised of grammars, glossaries, and books of prayers and hymns, in various Native American languages. Includes Huron, Mohawk, miscellaneous Iroquoian languages; Abenaki, Algonquin, Montagnais, Micmac, Ottawa; Slave, and unidentified Northwest Coast languages. Most were written by Jesuit missionaries before 1760. Also included is a register of Indian baptisms and marriages, and a brief history of the Huron Indians.

These letters and documents concern primarily the American Colony of Göttingen, including a record book containing historical data on the group (1855-1888), and the Algonquin, Choctaw, Illinois, and Naragansett Indian languages. Includes letters of: B. A. Gould, F. R. Hassler, Gauss, Sir Joseph Banks, J. F. Blumenbach.