Foxtrot, H 126bis, from 1920 goes beyond its occasional meaning: we would hardly find a parallel for it in our dance music of that time. Although its two-part form (A, B) and the division of the two parts (a, b, a; c, c') preserve the usual progression, including regular periodicity. The first part (A) is, however, notable for typically Martinu-like 'disguising manoeuvres' in the tonal plan, when the fairly conventional fifth circle of note relationships within the A part is skilfully masked by a double passage modulation. No less interesting here is the attempt to transcend the expressive stereotyping of period production (capriccioso in the A part, scherzando in the Trio), as well as the counterposition of a kind of 'legato style' in the melodic voice with the overall rhythmic environment of the piece, shaped primarily by the machine-like pulse of the left hand in the manner of ragtime. The key of the second movement (Trio, B) is in a then unusual second relative to the fundamental of the A movement, obscured, however, by the modulation to the "untrue" key of A major just before the Trio. Surprisingly, the last bars of the Trio modulate to C major, the starting key of the whole piece. Despite these finesse of the composer "from the other shore", Foxtrot remains dance music, limited also by the technical possibilities of the player to whom it was dedicated [to his dear friend Jeník Jílek].
Iša Popelka, Bohuslav Martinů: skladby pro Poličku. Praha: Supraphon, 1973, s. 33.