The title is a quotation from "Harmonie du soir" (Evening Harmony), included in Les Fleurs du Mal (The Flowers of Evil), a collection of poems by Charles Baudelaire (1821-1867). Debussy had already composed a song based on this poem in 1889, but this time, he may have intended to express the poem's worldview solely through the piano. Despite being notated in 3/4 time, the opening motif (measures 1-4) is instructed to be perceived in 5/4 time, with the addition of two beats (Musical Example 1). Similarly, in measures 24-26, where the opening motif reappears, a 5/4 phrasing is hinted at. Furthermore, in measures 31 and 33, coinciding with the appearance of fragments of the opening motif, the meter is changed to 4/4 without explicit indication (Musical Example 2). This deliberate disruption of the 3/4 time signature seems to correspond not only to the scene of the drifting atmosphere but also to the keywords "melancholy waltz" and "languid dizziness" from the original poem.

Musical Example 1: Opening

Musical Example 2: Unindicated change to 4/4 time, measures 31 and 33