(37) Iamblichus, in his dissertation on The Mysteries, describes how the spirit of the oracle--a fiery dæmon, even Apollo himself--took control of the Pythoness and manifested through her: "But the prophetess in Delphi, whether she gives oracles to mankind through an attenuated and fiery spirit, bursting from the mouth of the cavern; or whether being seated in the adytum on a brazen tripod, or on a stool with four feet, she becomes sacred to the God; whichsoever of these is the case, she entirely gives herself up to a divine spirit, and is illuminated with a ray of divine fire. And when, indeed, fire ascending from the mouth of the cavern circularly invests her in collected abundance, she becomes filled from it with a divine splendour. But when she places herself on the seat of the God, she becomes co-adapted to his stable prophetic power: and from both of these preparatory operations she becomes wholly possessed by the God. And then, indeed, he is present with and illuminates her in a separate manner, and is different from the fire, the spirit, the proper seat, and, in short, from all the visible apparatus of the place, whether physical or sacred."

(34) more quickly and completely to "the fumes of enthusiasm." Three days before the time set to receive the communications from Apollo, the virgin priestess began the ceremony of purification. She bathed in the Castalian well, abstained from all food, drank only from the fountain of Cassotis, which was brought into the temple through concealed pipes, and just before mounting the tripod, she chewed a few leaves of the sacred bay tree. It has been said that the water was drugged to bring on distorted visions, or the priests of Delphi were able to manufacture an exhilarating and intoxicating gas, which they conducted by subterranean ducts and released into the shaft of the oracle several feet below the surface. Neither of these theories has been proved, however, nor does either in any way explain the accuracy of the predictions.

(35) When the young prophetess had completed the process of purification, she was clothed in sanctified raiment and led to the tripod, upon which she seated herself, surrounded by the noxious vapors rising from the yawning fissure. Gradually, as she inhaled the fumes, a change came over her. It was as if a different spirit had entered her body. She struggled, tore her clothing, and uttered inarticulate cries. After a time her struggles ceased. Upon becoming calm a great majesty seemed to posses her, and with eyes fixed on space and body rigid, she uttered the prophetic words. The predictions were usually in the form of hexameter verse, but the words were often ambiguous and sometimes unintelligible. Every sound that she made, every motion of her body, was carefully recorded by the five Hosii, or holy men, who were appointed as scribes to preserve the minutest details of each divination. The Hosii were appointed for life, and were chosen from the direct descendants of Deucalion.

(3) Thence the prophecies and oracles are spoken in enigmas, and the mysteries are not exhibited incontinently to all and sundry, but only after certain purifications and previous instructions.