Progression. Common tones and inversional symmetry govern the progression of hexachords. The first and last hexachords are related by the inversion that exchanges E with G and F with F♯ (I₁₁). These four notes are the lowest in these measures (12 and 16). The second and third hexachords are related by T₁₁. The four shared tones (B♯, C♯, D, and D♯) occupy the outer voices in these measures (13–15). The last two hexachords are related by the inversion that produces no common tones (i.e. these two hexachords are complements of each other, producing a rare statement of all twelve tones in a short span of time). The transpositional intervals are generally very small—this both produces common tones and mirrors the smooth, conjunct motions of the melodic voices, especially their tendency to oscillate between tones a semitone or two semitones apart.