_Source._--Kindly condensed by Mr. Alfred Nutt from an English version
by Mr. S. H. O'Grady in _Ossianic Society's Publications_, vol. iii. The
oldest known version has been printed from fourteenth century MSS., by
Mr. Whitley Stokes, _Irische Texte_, iii. I. The story existed in some
form in the early eleventh century, as it is cited in the epic catalogue
contained in the Book of Leinster.
_Parallels._--Mr. Nutt in his _Studies on the Legend of the Holy Grail_,
p. 193, connects this visit of Cormac to the Otherworld with the
bespelled Castle incident in the Grail Legend, and gives other instances
of visits to the Brug of Manannan. Manannan Mac Lir is the Celtic
sea-god.