Midness

Rule (11) formulates that short, non-high vowels that agree in backness, roundness and midness (/a/: [- mid, - back, - round]; 10/: [+ mid, + back, + round]) are lengthened before voiceless fricatives.

After Bauer (1926/70:11) and Cantineau (1960:111), I analyse this mid height as the result of lowering conditioned by postvelars. It is phonetic because the high vowels are gradiently mid, their degree of midness depending on their degree of proximity to the postvelar. This is illustrated by (30a-b) in which, while the first-syllable vowels are [ɛ], the second-syllable vowels are perceptually a short diphthong from mid [ɛ] to high [ɪ].

The curly brackets are necessary because notions such as non-lowness, midness, etc. are not accessible, as such but only implicit in the naming.