 John Cleves Symmes purchased a large tract between the Little Miami River and the Great Miami River called the Symmes Purchase.Symmes had Ludlow survey a line between the sources of the Scioto and Little Miami to determine the boundary between the tracts, afterwards known as the Ludlow Line, the subject of decades of legislation and court action due to the difficulty in determining the source of the Scioto River.On August 25, 1788, Matthias Denman, Robert Patterson, and John Filson entered an agreement to found Cincinnati, with Ludlow taking Filson's place upon his death.