When entering "Jefferson" for the county and "Thornhill" on the keywords, I get a result for James Gibbons v Joseph Thornhill, from 1839. The cause is listed as "trespass and damages." What has me interested is in the 1830 US Census, James Gibbons is listed as the neighbor of Thomas Jones. Perhaps, just perhaps, there is a reference to Thomas Jones in this case file.
|Ancestry.com, 1830 US Census, Jefferson County, image 43 of 134|