les and Pozzuoli. The priests
must either have become used to the fumes, or have learnt some means of
counteracting them; otherwise their lives can hardly have been more
pleasant than that of the unfortunate dog which used to be exhibited in
the Naples grotto, though the control of these very realistic entrances
to the kingdom of Pluto must have been a very profitable business, well
worth a little personal inconvenience. Others are mentioned by Strabo at
Magnesia and Myus,[52] and there was one at Cyllene, in Arcadia.

In addition to these there were numerous special temples or places where
the souls of the dead, which were universally thought to possess a
knowledge of the future, could be called up and consulted--e.g., the
temple at Phigalia, in Arcadia, used by Pausanias, the Spartan
commander;[53] or the [Greek: nekyomanteion], the oracle of the dead, by
the River Acheron, in Threspotia, to which Periander, the famous tyrant
of Corinth, had recourse;[54] and it was here, according to Pausanias,
that Orpheus went down to the lower world in search of Eurydice.

Lucian[55] tells us that it was only with Pluto's permission that the
dead could return to life, and they were invariably accompanied by
Mercury. Consequently, both these gods were regularly invoked in the
prayers and spells used on such occasions. Only the souls of those
recently dead were, as a rule, called up, for it was naturally held that
they would feel greater interest in the world they had just left, and in
the friends and relations still alive, to whom they were really
attached. Not that it was impossible to evoke the ghosts of those long
dead, if it was desired. Even Orpheus and Cecrops were not beyond reach
of call, and Apollonius of Tyana claimed to have raised the shade of
Achilles.[56]

All oracles were originally sacred to Persephone and Pluto, and relied
largely on necromancy, a snake being the emblem of prophetic power.
Hence, when Apollo, the god of light, claimed possession of the oracles
as the conqueror of darkness, the snake was twined round his tripod as
an emblem, and his priestess was called Pythia. When Alexander set up
his famous oracle, as described by Lucian, the first step taken in
establishing its reputation was the finding of a live snake in an egg in
a lake. The find had, of course, been previously arranged by Alexander
and his confederates.

We still possess accounts of the working of these oracles of the dead,
especially of