The hornpipe: Terry Moylan's book gives nothing on its origins - other than saying it is found in many 19C. collections.

The song: Terry tells me that Frank Harte got it from Len Graham, the fine Northern singer. Len published a tape/booklet set of field recordings some years ago called "It's of my rambles...". It includes a fragment of this song from one John McGrath of Moneygran, Co. Derry. I can't find the tapes but suspect it uses the Anach Chuan tune. The booklet also includes a reproduction of a "chap-book" version under the title "Shiel's Nocturnal Vision" published "for the author" in 1840.

Regards