The Humphry and Moses Marshall papers consist of 233 items: 181 letters (including drafts), 15 legal documents, 11 manuscripts, 10 poems, 4 account books, and several each of books, letter books, arithmetic notebooks, and broadsides. The materials span from 1721-1863.
The first series contains correspondence and a few legal documents and writings, arranged chronologically. The correspondence dates from 1733 to 1863 and is predominantly incoming. Humphry Marshall is the recipient of the bulk of the material (approximately 40%), followed by Moses Marshall (approx. 30%). The majority of the outgoing correspondence comes from the two "letterbooks" kept by Moses Marshall in 1791 and 1793. These books contain correspondence from a couple of days each, but provide a record of Marshall's response to inquiries from clients.
The bulk of correspondence prior to 1800 relates to Marshall's horticultural and botanical operations. Substantial numbers of orders are for plants and seeds from clients in other parts of the United States, England, Ireland, France, and Germany, and communications with middle men in the operation detail methods of packaging and shipping. Also of botanical interest is the correspondence with Marshall's "agents" in the field, including Moses Mendenhall, John and James Watson, Matthias King, Samuel Kramsh, and James Kenny. These men were admirers and friends of Humphry Marshall, and provided him with specimens collected from various regions of the country. The unsuccessful search for wild Franklinia alatamaha is mentioned in several letters (April 8, 1788: "There is not a plant of the Franklinia to be found"), and other letters include discussions of scientific expeditions either actualized or planned, mostly involving the participation of Moses Marshall. On November 14, 1786, Humphry described the logistics of tracking down ginseng, providing insight into the duties of plant collectors: "both of you being obliged to…encamp in the mountains strike up a fire & lie by it all night in the morning…climb up the sides of the mountains and dig towards evening…about 20 days in Going and Coming home again & digging the roots packing up &c." The content of the letters does not indicate the Marshalls' scientific interests or abilities, but this correspondence provides documentation for the complex network used by the Marshalls to collect, sell and distribute plants.
Approximately 18 letters relate to the Revolutionary War (see "Subject Index" under "Additional Descriptive Data"). These include letters that indicate Marshall's support for the nonimportation agreements (January 6, 1775), second hand reports of the Battles of Lexington and Concord (April 25, 1775) and of Yorktown (August 24, 1781), and an important series of correspondence from Samuel Preston Moore relating to the resignation of the trustees of the General Loan Office when American revolutionaries seized control (June 17 and 21, 1777). Also significant are two letters from Quaker conscientious objectors on the morality of paying taxes to support military activities (undated c. 1780 letter; July 14, 1781), a letter relating to the North Carolina Regulator insurrection (March 3, 1771), and one concerning the arrest by American forces of Quakers suspected of Loyalist sympathies (September 6, 1777). Finally, in the pre-Revolutionary period, the letters of James Kenny provide excellent descriptions of plant collecting and the area around Fort Pitt in 1759-60.
The items from 1840-1863 mainly relate to Moses Marshall, Jr. Most notable in among them are several letters from William Darlington written as he was preparing his Memorial to Humphry and Moses Marshall in 1848 and 1849. Moses, Jr's pro-Confederacy political views are clearly expressed in the series of three speeches written during the Civil War, also included in the series.
The Poetry series includes 10 undated poems. The Bound Materials series comprises the arithmetic notebooks of Jacob Martin, whose relationship to the Marshalls is unclear; Darlington’s manuscript, Historical Introduction to Bartram & Marshall, Marshall's copy of Dover's Useful Miscellanies; and nine uncut and unfolded sets of signatures from Arbustrum Americanum.