Sullivan Co, TN and Washington Co, VA
as mapped in 1895 - Rand McNally
Rand McNally 1895
The Battle over the Boundary
Unfortunately while researching the Stophel/Stoffel lines, trying to figure out what state they were in could become confusing.  We aren't alone, seems the states had a similar problem!

These maps are slow loading since I had to make them large enough to be read.  Hopefully you will find them worth the wait!  They made shed a little light on the 'floating' state line.
Colton Map (around 1860)
"Battle of the Border" from Ancestry.com
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