I have heard the tannery story as well as them being engaged in horse trading from someone else with a public family tree. But the William I am looking at in my tree was born in 1787 and married to Ellender Archer. Their son Hamilton 1825 had a son John 1855 but I don't know if you connect to him. My greatgrandfather Charles Gabriel Downs is still a mystery. We have attached him to William and Ellender Downs on good research but we have no actual proof. He was born in Fauquier County, Virginia about 1830 and a lot of their records have been burned. It is further complicated by the fact that there were several Charles Downs born around the same time. Check the Medlee family tree for Downs - it might be helpful.
marieseroni@comcast.net