Frédéric Chopin's Impromptu No. 1 in A flat major, Op. 29 was composed in 1837.
Contents
Music
The Impromptu is in ternary form (ABA), the middle being in the key of F minor. A perpetuum mobile in triplets accompanies the piece.
In popular culture
In George du Maurier's novel Trilby, the title character, a singer who can perform only under the influence of hypnosis, performs the Impromptu in A-flat major as a wordless vocalise to end her concerts.
References
Impromptu No. 1 (Chopin) Wikipedia(Text) CC BY-SA