...its confluence with the Occoquan River, about twelve miles from the Potomac, and draining a considerable scope of country, from its source in Bull Run Mountain, to a short distance of the Potomac, at Occoquan . At this season habitually low and sluggish, it is, however, rapidly and frequently swollen by the summer rains until unfordable. The banks, for the most part, are rocky and steep, but abound in ...