Hi HS,
Could be? The dates are compatible at least, your William in 1815 and my Hugh in 1806.
With MonicaL's fantastic help I've managed to (educated) guess that Hugh was born, or at least lived, in Banagher parish in Derry. And that's about the sum total of my knowledge of Hugh! Do you have any idea what the best approach in Ireland is?
Cheers
Bill