William Hartshorne, a Pennsylvania Quaker, was a merchant in Alexandria. He was elected treasurer of the Potowmack Company on 17 May 1785 and served until Jan. 1800 (BACON-FOSTER description begins Corra Bacon-Foster. Early Chapters in the Development of the Patomac Route to the West. Washington, D.C., 1912. description ends , 61, 100).

The Virginia Act provided: “Whereas . . . many persons are willing to subscribe large sums of money to effect so laudable and beneficial a work; and it is just and proper that they, their heirs, and assigns, should be empowered to receive reasonable tolls forever, in satisfaction for the money advanced by them in carrying the work into execution, and the risk they run . . . it shall and may be lawful to open books in the city of Richmond, towns of Alexandria and Winchester in this state, for receiving and entering subscriptions for the said undertaking.” Hartshorne and John Fitzgerald were named in the act to be the managers of the Alexandria subscription book (HENING description begins William Waller Hening, ed. The Statutes at Large; Being a Collection of All the Laws of Virginia, from the First Session of the Legislature, in the Year 1619. 13 vols. 1819–23. Reprint. Charlottesville, Va., 1969. description ends , 11:510–11). Subscription books also were opened in Annapolis, Georgetown, and Frederick, Md.