(Update 1/9/2018: Interested in more about this ritual? Check out my more polished, fleshed-out writeup over on this page!)
In the course of my investigating PGM XIII.734ff for information the source and expansion of the Heptagram Rite, something caught my eye. As I noted before, after the ritual for the Heptagram, there appears to be a separate initiation ritual that has not survived in its entirety, resuming near the end of another spell invoking Dionysos and Michael; after that, there are a series of other invocations, incantations, and spells that collectively compose this mini-grimoire of the Tenth Hidden Book of Moses. Most of the entries in this section of the PGM are no more than lists of barbarous words, but one in particular is noteworthy, PGM XIII.934-949.
There’s no explanation of the section, only that it’s titled As the revelator Orpheus handed down in his private note. It’s interesting, and although entirely unrelated to the rest of the Heptagram Rites, I think it’s worthy of some note, at least for the sake of experimentation. For the sake of reference, I’m calling it “the Howl of Orpheus”, for reasons which may soon become clear. It goes like this, with the following instructions as given in the text with my probable interpretation (which, admittedly, is something of a departure from the exact text, but eh).
ΟΙΣΠΑΗ ΙΑΩ ΟΥΕΑ ΣΕΜΕΣΙΛΑΜ ΑΗΟΙ, son!
ΧΟΛΟΥΕ ΑΡΑΑΡΑΧΑΡΑΡΑ ΗΦΘΙΣΙΚΗΕΡΕ ΩΗΕΥΑΙΗ ΟΙΑΙ ΕΑΗ ΕΑΗ ΩΕΑ ΒΟΡΚΑ ΒΟΡΚΑ ΦΡΙΞ ΡΙΞ ΩΡΖΑ ΖΙΧ ΜΑΡΘΑΙ ΟΥΘΙΝ ΛΙΛΙΛΙΛΑΜ ΛΙΛΙΛΙΛΩΟΥ ΑΑΑΑΑΑΑ ΩΩΩΩΩΩΩ ΜΟΥΑΜΕΧ
Let your spirit begin to have a fluid boundary, permitting force to permeably flow through you. Breathe out completely, then inhale.
ΑΗΩ ΩΗΑ ΗΩΑ
Cease being permeable, sealing yourself with an empty spirit. Fill yourself up completely with breath and spiritual force, and begin to bellow-howl the next words, pushing everything out of you.
ΕΙ ΑΙ ΟΑΙ
Pull in yourself and fill yourself up with as much spiritual force as you can, shutting your eyes.
Come to me, god of gods! ΑΗΩΗΙ ΗΙ ΙΑΩ ΑΕ ΟΙΩΤΚ
Bellow out as much as you can, then let out whatever last air remains in your lungs with a sigh-hiss.
As Betz notes, this text is likely unconnected to the actual Orphic tradition or to Orpheus himself: “Orpheus, the legendary Thracian singer, had by this time become famous as a revelator. Many bogus words were attributed to him; nothing is none of this one.” Besides the general vowel permutations, this entry in the PGM is unusual for having generally unrecognizable barbarous words of power; ΛΙΛΙΛΙΛΑΜ and ΛΙΛΙΛΙΛΩΟΥ are kinda similar to the more popular ΛΑΙΛΑΜ, and ΦΡΙΞ and ΡΙΞ only dimly recall the Ephesian grammata (ΑΣΚΙΟΝ ΚΑΤΑΣΚΙΟΝ ΛΙΧ ΤΕΤΡΑΧ ΔΑΜΝΑΜΕΝΕΥΣ ΑΙΣΙΑ). This is certainly a different beast than other entries in the Tenth Hidden Book of Moses, especially with its addition of breathing/howling instructions.
At first blush, this seems to be an invocation of divinity, Aiōn or something comparable, but done in a rather interesting way. Most intonation and verbalization instructions in the PGM include things like “popping sound”, “hiss”, “[howling] like a baboon”, “[barking] like a dog”, and so forth, but this is outright telling the magus to bellow-howl. Such deep breathing and howling can definitely induce an altered state of consciousness, and having done it before myself on some occasions (not with this specific ritual), I can see how such a ritual could perhaps bring one face-to-face with a divine power, if not outright knocking oneself into an ecstasy. Perhaps preceding this with a period of purity and fasting, or subsisting on an Orphic diet (strict vegetarian without killing) could be recommended. Of course, that’s just an idea, since there’s really nothing to suggest that this invocation is Orphic in any sense.
Still. Could be interesting to give it a shot.