Fully-fledged bitonality can be heard in the large-scale Piano Sonata (1921-4), a response to the horror and futility of war, and by turns grim, elegiac and visionary. The sound-world can still be related to the music of Bridge's English contemporaries Bax and Ireland at their most astringent, but with the Third String Quartet (1927), the language approaches more closely that of his central European contemporaries. Nine or ten of the twelve chromatic notes are kept in play in each bar and the bitonal chord of a minor triad with a major triad a tone higher above becomes a Bridge fingerprint.
Also written in this expressionist style, the elusive and uncanny Rhapsody for two violins and viola (1928) forms the best example of Bridge's preoccupation with arch form, and both the grander Piano Trio (1929) and Violin Sonata (1932) draw on additional harmonic resources; seconds in the trio, fourths in the sonata.
The orchestral works from this period share in the development of Bridge's idiom, but usually in a less extreme form. However, similar moods are explored; vitality and exuberance in Enter Spring (1927), a sombre, muted despair in There is a Willow Grows Aslant a Brook (1927) and eerie, ghostly half-lights in Phantasm for piano and orchestra (1931). Oration for cello and orchestra (1930) is another work inspired by war, but in contrast to the Piano Sonata ends positively; the passionate indictment voiced by the cello finally gives way to an epilogue of withdrawn mourning providing consolation and muted hope.
Concentration on the more open sound of fourths and fifths to create polytonal chords in the Fourth String Quartet (1937) suggests a more Neoclassical approach, evident too in the sparse, pithy Divertimenti (1934-8) for woodwind. Unfortunately this development could hardly be pursued much further due to Bridge's ill health, but the overture Rebus (1940) was completed, and a movement for string orchestra was sketched in all but its final few bars. For the last three weeks before his death, Bridge was working on the page-proofs for Phantasm.