"The Fairy Faith in
Celtic Countries: Its Psychical Origin and Nature", a most laborious
as well as ingenious work, whose object is to prove "that the origin
of the fairy faith is psychical, and that fairyland, being thought of
as an invisible world within which the visible world is immersed as
an island in an unexplored ocean, actually exists, and that it is
peopled by more species of living beings than this world, because
incomparably more vast and varied in its possibilities." This may be
added as a fourth theory to account for the existence of fairies, and
it may be further stated here that the Irish popular belief in ghosts
attributes to some of their departed spirits much of the same
violence and malice with which fairies are credited. Mr. Jeremiah
Curtin gives striking instances of this kind in his book, the _Folk
Lore of West Kerry_.

It became necessary, therefore, for the Gaels who believed in the
preternatural powers of the fairies for good and ill to propitiate
them as far as possible. On May eve, accordingly, cattle were driven
into raths and bled there, some of the blood being tasted, the rest
poured out in sacrifice. Men and women were also bled on these
occasions. The seekers for buried treasure, over which fairies were
supposed to have influence, immolated a black cock or a black cat to
propitiate them. Again, a cow, suffering from sickness believed to be
due to fairy malice, was bled and then devoted to St. Martin. If it
recovered, it was never sold or killed. The first new milk of a cow
was poured out on the ground to propitiate the fairies, and
especially on the ground within a fairy rath. The first drop of any
drink is also thrown out by old Irish people. If a child spills milk,
the mother says, "that's for the fairies, leave it to them and
welcome." Slops should never be thrown out of doors without the
warning, "Take care of water!" lest fairies should be passing
invisibly and get soiled by the discharge. Eddies of dust upon the
road are supposed to be caused by the fairies, and tufts of grass,
sticks, and pebbles are thrown into the centre of the eddy to
propitiate the unseen beings. Some fairies of life size, who live
within the green hills or under the raths, are supposed to carry off
healthy babes to be made fairy children, their abstractors leaving
weak changelings in their place. Similarly, nursing mothers are
sometimes supposed to be carried off to give the breast to fairy
babes, and hands