Prometheus: Poem of Fire

Prometheus: The Poem of Fire, Op. 60 (1910), is a symphonic work by the Russian composer Alexander Scriabin for piano, orchestra, optional choir, and clavier à lumières or "Chromola" (a color organ invented by Preston Millar, in fact rarely featured in performances of the piece, including those during Scriabin's lifetime). Prometheus is only loosely based on the myth of Prometheus. A typical performance lasts about 20 minutes.

The music is complex and somewhat dissonant, based almost entirely around various inversions and transpositions of Scriabin's matrix sonority: A D♯ G C♯ F♯ B. Sabaneyev referred to this chord, which opens the work in an eerily static fashion, as the "chord of Prometheus". It has subsequently become known as the "mystic chord". But after unrelieved dissonance throughout, the symphonic poem ends with a resplendent F-sharp major triad, the only consonant sonority in the entire composition.

The part for color organ is notated on a staff of its own, in treble clef at the top of the score, and consists of two parts: one changes with the harmony, and always goes to the root note of the prevailing harmony, and thus produces the color Scriabin associated with each key; the other consists of much longer notes sustained through many bars, and does not appear to be related to the harmony (or therefore to the first part), but for the most part slowly rises up the scale a whole-tone at a time, the changes being several pages of score apart, or a minute or two apart. It is not clear what relationship this part has to the first part, or to the music as a whole. The score does not explain how two different colors are to be presented at the same time during a performance. This color organ part also contains three parts briefly at one point in the score.

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