Schubert was just 20 when he composed the song “Ach neige, du Schmerzenreiche” – Gretchen’s prayer from Goethe’s Faust – for piano and voice. However, it remained a fragment, ending after just 43 bars with the line “The heart within me breaks”. A change of key at the bottom of the second page suggests a lost continuation. Several composers have written endings, including Benjamin Britten.