Chromatic circle "discrete" structure, and there is no obvious way to assign pitch classes to each of its points. A pitch constellation is a graphical representation of pitches used to describe musical scales, modes, chords or other groupings of pitches within an octave range. It consists of a circle with markings along the circumference or lines from the center which indicate pitches. Most pitch constellations use of a subset of pitches chosen from the twelve pitch chromatic scale. In this case the points on the circle are spaced like the twelve hour markings on an analog clock where each tick mark represents
Tonic sol-fa latter more directly represents the intervals between pitches in any given key signature. In Curwen's system, the notes of the major scale (of any key) are notated with the single letters d, r, m, f, s, l, and t. For notes above the principal octave, an apostrophe follows the letter; notes below the principal octave have a subscript mark. Chromatic alterations are marked by the following vowel, "e" for sharp (pronounced "ee") and "a" for flat (pronounced "aw"). Thus, the ascending and descending chromatic scale is notated: Such chromatic notes appear only as ornaments or as preparation for a modulation;