A roundel (not to be confused with the rondel) is a form of verse used in English language poetry devised by Algernon Charles Swinburne (1837–1909).
[1] He dedicated these poems to his friend Christina Rossetti, who then started writing roundels herself, as evidenced by the following examples from her anthology of poetry: Wife to Husband; A Better Resurrection; A Life's Parallels; Today for me; It is finished; From Metastasio.
Its jewel of music is carven of all or of aught - (B) Love, laughter, or mourning - remembrance of rapture or fear - (A) That fancy may fashion to hang in the ear of thought.
As a bird's quick song runs round, and the hearts in us hear (A) Pause answer to pause, and again the same strain caught, (B) So moves the device whence, round as a pearl or tear, (A) A roundel is wrought.
The fourth roundel became the song "Roundel: The little eyes that never knew Light," set to music by the English composer Edward Elgar.