That's interesting Jack. In the English Folk Songs from the Southern Appalachians it's notated slightly differently. The Cs in bars 2 and 8 are both sharp in the version there (otherwise it's identical). Perhaps they thought mixing C# and Cnat was too difficult for the school version.

leeneia (sorry for earlier careless spelling) - as Jack say's there's no G in the midi on the Irish site. The tonality is clearly D, though with the 7th varying - there are both C and C# in the midi.

Mick