MSS.21552-21554 contain letters from persons whose letters are more substantially represented, notably Sir John Barbirolli and Percy Grainger. From MS.21554, folio 88, the correspondence is in a chronological sequence.

Subjects dealt with include Jenny Lind's visit to Scotland, Kreisler's claim to have originated the theme for the Waltz from Coppelia, Verdi's reputed visit to Scotland, the Pachmann school, and the music of Elgar and Wagner in general.