by the bards of Gaul, referred to by Diodorus, may have
been believed to possess similar powers.[1130] Contrariwise, the
_Filid_, on uttering an unjust judgment, found their faces covered with
blotches.[1131]

A magical sleep is often caused by music in the sagas, e.g. by the harp
of Dagda, or by the branch carried by visitants from Elysium.[1132] Many
"fairy" lullabies for producing sleep are even now extant in Ireland and
the Highlands.[1133] As music forms a part of all primitive religion,
its soothing powers would easily be magnified. In orgiastic rites it
caused varying emotions until the singer and dancer fell into a deep
slumber, and the tales of those who joined in a fairy dance and fell
asleep, awaking to find that many years had passed, are mythic
extensions of the power of music in such orgiastic cults. The music of
the _Filid_ had similar powers to that of Dagda's harp, producing
laughter, tears, and a delicious slumber,[1134] and Celtic folk-tales
abound in similar instances of the magic charm of music.

We now turn to the use of amulets among the Celts. Some of these were
symbolic and intended to bring the wearer under the protection of the
god whom they symbolised. As has been seen, a Celtic god had as his
symbol a wheel, probably representing the sun, and numerous small wheel
discs made of different materials have been found in Gaul and
Britain.[1135] These were evidently worn as amulets, while in other
cases they were offered to river divinities, since many are met with in
river beds or fords. Their use as protective amulets is shown by a stele
representing a person wearing a necklace to which is attached one of
these wheels. In Irish texts a Druid is called Mag Ruith, explained as
_magus rotarum_, because he made his Druidical observations by
wheels.[1136] This may point to the use of such amulets in Ireland. A
curious amulet, connected with the Druids, became famous in Roman times
and is described by Pliny. This was the "serpents' egg," formed from the
foam produced by serpents twining themselves together. The serpents
threw the "egg" into the air, and he who sought it had to catch it in
his cloak before it fell, and flee to a running stream, beyond which the
serpents, like the witches pursuing Tam o' Shanter, could not follow
him. This "egg" was believed to cause its owner to obtain access to
kings or to gain lawsuits, and a Roman citizen was put to death in the
reign of Claudius for bringing such a