Hi not entirely sure how this site works, but came across your ancestor Bryan McCormick. Brian would be my great great uncle. His Parents Sara McArdel, born 1795, and James McCormick, born 1795, are my direct ancestors, being my Great Great Great Grandparents.
Bryan was born in Crossmaglen Ireland in 1818 and died in Argyll Scotland in 1873.
Somewhere along the way here in Ireland at least, the name changed to McCormack and that was the surname of my maternal grandparents. So in the 1901 Census the family here in Ireland went by McCormick, but by the 1911 Irish Census the surname was McCormack.
Would love to find out more about the ancestry.
Sinead