‘Altarwise by owl-light’ is one of Thomas’s most intransigent poems, an intricately woven text of images and symbols. It has generated, over the years, a great variety of interpretations ranging from the astrological, to the Freudian to the Surrealistic . The reading of this poem often involves a search for sources, the unravelling of references and allusions. For instance, in some of the sonnets’ most seemingly surreal lines , at the end of Sonnet V, an unexpected source has been discovered by Walford Davies and Ralph Maud. In - Cross-stroked salt Adam to the frozen angel Pin-legged on pole-hills with a black medusa By waste seas where the white bear quoted Virgil And sirens singing from our lady’s sea-straw. - the image of the ‘wast...