On the Distribution of Rounded Medial in Old Chinese: the Separate between Rounded and Unrounded Rhymes in Book of Songs

Based on a database of rhymings in Book of Songs, this paper proves that in old Chinese: (1) Dental-ending final (with coda [-t/-n/-d/-r] could have rounded medial [-u-] or [-w-]. (2) Finals in labial syllable (with labial initial) could be classified into two categories: Rounded and unrounded. (3) Velar-ending final (with coda [-k/-ŋ/-g]) had no rounded medial, but could follow a labialized initial [kw-] or [pw-]; and the labialized [w-] gave rise to rounded medial [-w-] in middle Chinese. (4) In Book of Songs, there was a tendency to distinguish rounded rhymes from the unrounded.