Several people have mentioned the South Branch of the Potomac. I recently discovered an article on this subject. If you have access to a good genealogical or historical library, you might be able to locate the same article. Here's the reference: A publication (probably a monthly publication) entitled WEST VIRGINIA HISTORY Volume XXXVIII October 1976 Number 1 The title of the article is: EARLY FAIRFAX LAND GRANTS AND LEASES ALONG THE SOUTH BRANCH OF THE POTOMAC by Charles Morrison. (starts on page 1).