_Alexandria Gazette_, October 4, 1839. The obituary notice for Thomas Moss states that he died on October 2 after a long illness, having been a Justice of the Peace for many years, and also having served as a member of the State Legislature and as county court clerk. The Archives of the Virginia House of Delegates show that Thomas Moss was a Delegate from Fairfax County for the 1828-1829 biennium. (Honorable George Rich, January 2, 1970; personal communication.) [21] K. M. Willis, "Old Fairfax Homes Give Up A Secret," _American Motorist_, May 1932, p. 16; Johnston, _Clerks_, p. 174. [22] M. Herndon, _Tobacco in Colonial Virginia_ (Williamsburg: Virginia 350th Celebration Corp., 1957), pp. 7-8, indicates that tobacco was introduced into Northern Virginia by the settlers who moved into the Rappahannock and Potomac areas around 1650. By the end of the seventeenth century, Herndon states, tobacco farming dominated the lowlands all along the Rappahannock and Potomac Rivers below the fall line. F. Harrison, _Landmarks of Old Prince William_ (Berryville: Chesapeake Book Co., 1964), pp. 148-150. Also to be noted is the fact that settlement above the fall line was not permitted prior to 1722 because of treaty provisions with the Iroquois. By the Treaty of Albany in 1722, the Iroquois withdrew west of the Blue Ridge. [23] Herndon, _Tobacco_, pp. 14-16, cites introduction of plant bedding practices, use of animal-drawn plows instead of hand hoes, and improved methods of curing tobacco as responsible for increasing the yield of the tobacco farm. [24] _Ibid._, p. 10. [25] Frederick Gutheim. _The Potomac_ (New York: Grosset & Dunlap, 1968), p. 98. [26] R. B. Davis, _Intellectual Life in Jefferson's Virginia_ (Chapel Hill: University of North Carolina Press, 1964), p. 167, notes that in 1773 the Society for the Advancement of Useful Knowledge was formed in Williamsburg, followed by the Philadelphia Agricultural Society in 1780, and the Richmond Society for Promoting Agriculture in 1810, all dedicated to working for the improvement of farming. [27] A list of these writings on agriculture was compiled by E. G. Swern in 1913 and published by the Virginia State Library. [28] Davis, _Intellectual Life_, pp. 159-160, 167. Among the inventions of the McCormick family were threshing machines, hydraulic machines, a hemp-brake, blacksmith's bellows, and self-stoppers for grist mills. Other patents issued to Virginians dealt with plows, grain screens, rice hullers, hemp and flax breakers, corn shellers, beehives, clover seed cleaners and gatherers, tobacco presses, and corn grinders.