Hithe Percy French one is called "The Emmigrants letter", beautiful song.... I'll do a search before I post it.
I like Clannad's "Green fields of Gaodthdobhair"(pronounced Gweedore), although it's written by the person still in Ireland watching the boat going away.
And although they're not emmigration songs....... they're transportation ones..... it's still people reminiscing about home I like "Back home in Derry", and "The land where the shamrocks grow". (There are earlier threads on both of these.)
Slainte
alison