Oh, O'Leary is dead and O'Riley don't know it
O'Riley is dead and O'Leary don't know it
They're both of them dead and they're in the same bed
And neither one knows that the other one's dead.


Found it in a book when I was a kid. Have no idea what the right tune is. I sing it to a bit that got used a lot in old movies to indicate that someone was from Ireland.