His headstone says he was "22 years, 11 months" old when he passed 19 April 1851, so he must have been born about 1828.
Sources
Find a Grave, database and images (https://www.findagrave.com/memorial/101528943/james-l-dowden : accessed 19 June 2022), memorial page for James L Dowden (unknown–19 Apr 1851), Find A Grave: Memorial #101528943, citing Bowman-Flatwoods Cemetery, Vanderbilt, Fayette County, Pennsylvania, USA ; Maintained by Ancestor Searcher (contributor 47848612) .
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