With a wave of this he stirred and led them on
and the ghosts trailed after with high thin cries
as bats cry in the depths of a dark haunted cavern,
shrilling, flittering, wild when one drops from the chain –
slipped from the rock face, while the rest cling tight…
So with their high thin cries the ghosts flocked now
and Hermes the Healer led them on, and down the dank
moldering paths and past the Ocean’s streams they went
and past the White Rock and the Sun’s Western Gates and past
the Land of Dreams, and they soon reached the fields of asphodel
where the dead, the burnt-out wraiths of mortals, make their home.

– Homer

The Odyssey, Book 24, lines 5-15. With a wave of his gold wand, Hermes leads the souls of the crying suitors into Hades. As well as being the messenger of the gods, Hermes is also the conductor of the dead to the underworld. In an epic simile the cries of anguish of the suitors are compared to the squeals of bats hanging from the roof of a large dark cave.