In the book Alice notes that the melody of the White Knight's 'own devising' is, in fact, 'I give thee all, I can no more' (a.k.a. 'My Heart and Lute') -- by Irish poet Thomas Moore. Here is a GORGEOUS countertenor + classical guitar rendition of said tune by Tu Shi Chiao: https://youtu.be/BxTV0IEVYb4  ...I love countertenors OMGs…