trouble crossed the second. In many mythologies and in world-wide folk-tales there is a narrow bridge or bridges leading to the realm of the dead. Even Mohammed in the _Koran_ declares it necessary to cross a bridge as thin as a hair, if one would enter Paradise. And in living folk-lore in Celtic countries, as we found among the Irish peasantry, the crossing of a bridge or stream of water when pursued by fairies or phantoms is a guarantee of protection. There is always the mystic water between the realm of the living and the realm of subjectivity.[279] In ancient Egypt there was always the last voyage begun on the sacred Nile; and in all classical literature Pluto's realm is entered by crossing a dark, deep river,--the river of forgetfulness between physical consciousness and spiritual consciousness. Burns has expressed this belief in its popular form in his _Tam O'Shanter_. And in our Arthurian parallel there is a clear enough relation between the beings inhabiting the invisible realm and the Brythonic heroes and gods. How striking, too, as Gaston Paris has pointed out, is the similarity between Melwas' capturing Gwenhwyvar as she was in the woods a-maying, and the rape of Proserpine by Pluto, the god of Hades, while she was collecting flowers in the fields.[280] A curious matter in connexion with this episode of Gwenhwyvar's abduction should claim our attention. Malory relates[281] that when Queen Guenever advised her knights of the Table Round that on the morrow (May Day, when fairies have special powers) she would go on maying, she warned them all to be well-horsed and _dressed in green_. This was the colour that nearly all the fairy-folk of Britain and Ireland wear. It symbolizes, as many ancient mystical writings declare, eternal youth, and resurrection or re-birth, as in nature during the springtime, when all vegetation after its death-sleep of winter springs into new life.[282] In the _Myvyrian Archaiology_,[283] Arthur when he has reached the realm of Melwas speaks with Gwenhwyvar,[284] he being on a black horse and she on a green one:--'Green is my steed of the tint of the leaves.' Arthur's black horse--black perhaps signifying the dead to whose realm he has gone--being proof against all water, may have been, therefore, proof against the inhabitants of the world of shades and against fairies:-- Black is my steed and brave beneath me, No water will make him fear, And no man will make him swerve.