In reply to 13 April Guest - who I suspect is not unrelated to erstwhile contributor Jack Maloney - because most of us here would rather have facts than specious pilings of non-fact upon non-fact.

It seems clearly established by those who know (not me!) that both "only for nights" and "Ballygrand" are 1960s inventions of the Clancy Brothers who either could not understand or did not care what was being sung on one of Dominic Behan's recordings. Neither term occurs in any version before the Clancys', and so all this stuff about a lover sailing to Ballygrant in Islay and black marble at nearby Kilmeny is entirely irrelevant to the origins of a song which dates from the 1830s at the latest. To repeat, neither "only for nights" nor "Ballygrand" appear in any known version of Carrickfergus prior to the Clancy Brothers 1964 album "The First Hurrah!"

As earlier contributors have pointed out, Occam's razor is a wonderful tool. The song says there is black marble at Kilkenny, and Kilkenny is famous for its black marble (which is in fact limestone, but so what). So why look for somewhere else that has black marble and is not Kilkenny but has a similar name - particularly if you end up with an insignificant place on a small island in a different country?

Incidentally and probably finally, has anyone pursued the O'Toole angle any further? He is the somewhat improbable link between a Gaelic/English macaronic broadsheet published in Cork around 1830 and the two versions of Carrickfergus recorded by Dominic Behan in the 1960s. O'Toole says he heard/learned it in Kerry in 1946 (i.e. when he was 13 or 14), and Behan says Kerry is where O'Toole spent his childhood. But the Wikipedia article on O'Toole, based on his autobiography, says that he was born in 1932 in either Co. Galway or Leeds, Yorkshire (he has birth certificates from both, with different dates!) and by age 1 was definitely in the North of England where he spent the next 5 years travelling around local racecourses with his father who was an itinerant bookmaker. After that the chronology is a bit confused but he spent 7 or 8 years at a Catholic SECONDARY (i.e. age 11+) school in Leeds. So where is there room for a Kerry childhood that includes him at age 13/14? Not saying it's not possible; just saying it looks a bit difficult to fit in.

And another rather relevant thing from the Wikipedia article is that O'Toole said, apparently in a 2006 interview on US National Public Radio, that before he became a student at the Royal Academy of Dramatic Arts in 1952 he had been rejected by the prestigious Abbey Theatre, Dublin "because he couldn't speak Irish". Without the Erse, what would a 14 year old O'Toole have made of someone singing - to who knows what tune - the 1830s macaronic but primarily Gaelic broadsheet "The Young Sick Lover"? Of course, O'Toole may have heard a watered down and anglicised version of the broadsheet - but who would have sung that in 1946 in the Gaeltacht?