This movement is again centered on the intervals that were important and most prominent in movement 1 and 3: major seventh, minor ninth and minor second intervals. Especially one of these intervals stands out: the interval the movement starts with: Bb-B, at the same time the penultimate note in both the high and low range of a marimba with A as its bass note (the most common instrument type at the time the piece was composed (1).
The full reservoir of chromatic notes is displayed in the first line of this movement and serves as the tonal material for the whole movement.The chords as described in the third movement, the ones where a tonal triad is combined with a major seventh or minor ninth interval of one of its voices, are present again in the grace note slur that envelopes the whole third page of the fourth movement. Also, the repeated chord at the end of that page is an example of this type of chord. Chung points out an interesting mirror inversion of material in line 2 of this movement, mirroring the material across the two augmented chords in the middle of the line (2).
Chung again made an estimation on how long the different fermatas throughout the movement can last in his analysis (3). He also set the tempo to 110 BPM per eighth note to match the ‘Allegretto’ tempo marking of this movement.
The biggest structural element in rhythm in this movement is the difference between the quasi-measured musical material and the free grace-note passage on page 3 of this movement. We think it is advised for the quasi-measured parts to subdivide the musical text into eighth notes and dotted eighth notes and to add measures to the score, as we did for the first and second movement of this piece. This will help the performer to follow the written musical text as close as possible. Different measures can be applied to this text, the performer decides which way he or she wants to go.