That incubation was a ready means of diving into the future, needs no demonstration. Although its practice was chiefly resorted to in cases where medical aid was desired, it was still made use of in every other case, in which the ancient oracles were consulted. Whether it arose in Greece, or migrated thither from the East, is a point with which the ancients have left us unacquainted, though they advert to its prevalence amongst those who were called barbarians. Strabo has several instances of it, and particularly mentions a place in the Caspian sea, where such an oracle existed;[91] he also relates, in his celebrated account of Moses, that this law-giver laid it down, in common with the priests of Esculapius, that to those who led a chaste and virtuous life the deity would vouchsafe prophetical visions in his sanctuary; but to those who were of idle and impure habits, they would be denied.[92]
Pomponius Mela even mentions a savage nation, in the interior of Africa, who laid themselves down to sleep on the grave-stones of their ancestors, and looked upon the dreams they had on those spots as oracles from the dead.[93] We shall see, hereafter, that this superstition was equally indigenous among the Egyptians. Although it be doubtful whether the Greeks owed this species of divination to their own invention or not, its existence may at least be traced as far as the earliest ages of their history; notwithstanding no positive mention of it has been made either by Homer or the authors following him.
The oracular power of dreams, and the sanctuaries where they are supposed to be dispersed, have been diffusely treated of in the compilations of Van Dale and other learned writers. These species of oracles were in high estimation, even in the most enlightened and flourishing periods of Greece; it is somewhat singular, however, that no people cherished them more devoutly than the Spartans, who depended altogether upon oracles in their weightiest affairs of state. Of all the civilized nations of Greece, Sparta always approved herself the most superstitious; her advancement was rather the effect of her policy, than of any stimulus given to her civilization by science. This consideration will enable us to account for the powerful influence which, even in the latest stages of Lacedemonian story, attached to the responses of Passiphae, a local goddess of Thalame, but little known beyond the confines of Laconia. The extent of their influence is particularly evident in the history of Agis and Cleomenes.[94]
The greater part of these somnambulistic oracles were ascribed to persons who had distinguished themselves as great dreamers when on earth. In old times there was a description of prophets who pretended to prepare themselves for the foreboding of future events through the medium of sacred dreams. They were classed under the appellation of [Greek: Oneiroploi], to which rank the most celebrated Vates of the heroic age belonged. In this way it was that a sacred spot was dedicated to Calchus, whence he gave his responses in dreams after his decease: this spot lay in Daunia, on the coast of the Adriatic. The supplicant's offices began with the offering up of a ram, on whose skin he laid himself down, and in this situation, received the instruction he sought for.[95] Amphilocus, a contemporary soothsayer, who accompanied the Epigoni in the first Theban war, had a similar oracle at Mallos, in Cilicia, which Pausanias asserts, even at the close of the second century, to have been the most credible of his age; it is also mentioned by Dion Cassius, in his history of Commodus.[96]
The most famous, however, of this class of oracles, was that of Amphiaraus, the father of Amphilocus, which was one of the five principal oracles of Greece; he had signalized himself as a sapient soothsayer in the first Theban war; and his oracle was situated at Oropos, on the borders of Boetia and Attica. Of all others this deserves our most particular attention, as it was resorted to more frequently in cases of infirmity and disease, than in any other circumstances. His responses were always delivered in dreams, in whose interpretation, as he was the first to possess that faculty. Pausanias says he received divine honours. Those who repaired to Amphiaraus's oracle to supplicate his aid, laid themselves down in the manner we have just related, after several preparatory lustrations and sacrifices, on the skin of a ram slain in honour of the god, and awaited the dreams, which were to unfold the means of their different cures.
Lustrations and sacrifices were not, however, the only preparatives for inducing the visionary disposition. The priests subjected the patients to various others, which Philostratus affirms[97] to have been very instrumental towards rendering the sleeper's mind clear and unclouded. Part of these preparatives consisted in one day's abstinence from eating, and three, nay, even in some cases, fifteen days' abstinence from wine, the common beverage of the Greeks. This was the practice also with other oracles; nor were the priests in the meantime insensible to their own interests on these occasions; for those who were cured by Amphiaraus's revelations were permitted to bathe in the sacred waters of a fountain, into which they were enjoined to cast pieces of gold and silver, which were destined, most probably, to sweeten the labours of his officiants.
The oracles, whose intervention was principally or altogether sought for the healing of the sick by means of divination founded on dreams, were scattered over Greece, Italy, Egypt, and other countries. As regards those of Egypt, it may be remarked, that although many of the Egyptians believed there were thirty-six demons, or aerial deities, each of whom had the care of a certain portion of the human frame, and when that portion was diseased, would heal it on the patient's earnest prayer, yet a variety of their oracles, such as those of Serapis, Isis, and Phthas, the Hephaestos of the Greeks, appertained to the class, which is the present object of our inquiry.
The oracle Serapis was situated near Canopus; it was visited with the highest veneration by the wealthiest and most illustrious Egyptians, and contained ample records of miraculous cures which that god had performed on sleepers.[98] Isis, it is said, effected similar cures in her lifetime, whence it became her office, in her after state of deification, to reveal in dreams the most efficacious remedies to the sick. Indeed the healing powers of this goddess were such, that, as we are told by Diodorus,[99] the remedies she prescribed never failed of their effect, and that convalescents were daily seen returning from her temple, many of whom had been abandoned as incurable by the physicians.
The third oracle of the sick was consecrated to Phthas, and lay near
Memphis, but it is seldom mentioned by the ancients.[100]
In Italy there existed two oracles, whose responses were imparted in dreams, before the worship of Esculapius was introduced from Greece. One of them only belongs to this place, that of the physician Podalirus, in Daunia,[101] which is mentioned by Lycophron.[102] Subsequently it is well known incubation was practised after the Grecian form in the Roman temple of Aesculapius on the Insula Tiberina.[103]