I would love to see some of those old letters! I will have to get in touch with my cousin David Knowles to see if he has access to any wills, death or marriage records from David Knowles on down because that is what DAR requires. I think that David does have access to this info. David, if you see this, email me! The genealogist for the DAR is going to try to help me find these records as well.
I just took a college course on the pioneers that left the east coast and headed to the western frontier. There were a lot of them! I have been intrigued that instead of going "west", my ancestors just went further and further south. I am thankful for that because I was born here in Florida and it's beautiful and the weather is lovely! Thanks, ancestors!
Somewhere at home I have a scan of a photo of a Stephen and Pollyann Knowles in front of a crude cabin. I don't know if this is your ancestor or not or if it will ring a bell for anyone. I also have a scan of a photo of David James Knowles with a pipe in front of a palm tree.