A cappella Publisher Desc.  "To Sleep" by Nancy Wertsch is for a cappella mixed choir SATB (extensive divisi to 8 parts) and soprano soloist. The text by 18th century poet John Keats (1795-1821) is an ode to a personification of Sleep, with the peace of death as a metaphor for deep peaceful sleep. The choir provides a sustained and slow moving accompaniment to the soloist's floating melody with unsettled harmony, shifting chromatic lines, and portamento effects in search of rest which eases its way in as the piece settles into quiet slumber.