This state may be prolonged for months or years. Its duration depends on the strength of the material instincts of the soul. Still, good or evil, infernal or celestial, this soul will gradually become conscious of itself and of its new condition. Once free from its body, it will escape into the abysses of the terrestrial atmosphere, whose electric streams carry it here and there, and whose many-shaped inhabitants, wandering about, more or less like itself, it is beginning to perceive, like fugitive flashes in a thick mist. Then there begins a desperate, vertiginous struggle on the part of the soul, which is still dull and heavy, to rise into the upper strata of the air, to free itself from earthly attraction and reach, in the heaven of our planetary system, the region proper to it and which friendly guides alone can show it. But before this can take place, a long period must often intervene. This phase of the life of the soul has borne different names in religions and mythologies. Moses called it Horeb; Orpheus, Erebus; Christianity, Purgatory, or _the Valley of the Shadow of Death_. The Greek initiates identified it with the cone of shadow which the earth is always trailing behind it, which shadow reaches as far as the moon; for this reason they called it the _abyss of Hecate_. In these mirky depths, say the disciples of Orpheus and of Pythagoras, are tossed to and fro the souls which make desperate efforts to reach the circle of the moon, though the violence of the winds beats them back to earth by thousands. Homer and Virgil compare them with whirling leaves, or swarms of birds maddened by the tempest. The moon played an important part in ancient esoterism. On its surface, facing the heavens, the souls were regarded as purifying their astral body before continuing their celestial ascent. It was also supposed that heroes and great spirits took up their abode for a time on the portion of its surface turned towards the earth, in order to clothe themselves in bodies appropriate to our world before reincarnation. There was attributed to the moon, in a certain measure, the power to magnetize the soul for earthly incarnation, and to demagnetize it for its heavenly abode. In a general way, these assertions, to which initiates attached a meaning that was at once real and symbolical, signified that the soul must pass through an intermediary stage of purification and free itself from the impurities of earth before continuing its journey.