Jaimie James discusses the poetry of William Butler Yeats in relationship to his practice of magic in "W.B. Yeats, Magus" (Lapham's Quaterly).
"Magic," writes James, "imbrued Yeats’ thinking so profoundly that it’s nearly impossible to disentangle the strands without rending the garment. Kathleen Raine, a poet deeply influenced by Yeats, offered a useful formula: 'For Yeats magic was not so much a kind of poetry as poetry a kind of magic, and the object of both alike was evocation of energies and knowledge from beyond normal consciousness.' The salient word there is 'evocation,' casting the poet as a magus conjuring verbal spirits, not from his imagination but from a higher, or a deeper, place."
Art above: A detail from "The Alchemist" by Edmund Dulac (1882-1953)