I have Norvell Powell Robertson, b. 22 May 1765 as a 4th great grand uncle. This is all the info I have. Could this be the same as your Norvel Robertson?
I also have a Benjamin Franklin Knight, b. 1 Aug 1817 as a distant relative by marriage. I also have little info on him.
Could you help fill in some blank spaces if these two match those you mentioned in your Rootsweb post 0f 14 Feb?