Debussy vs Ravel, Part 3

I've been laying out some of the context and background to these two composers. In the last post on the topic I talked about the aesthetic context for Debussy's music. Time to get back to Ravel. There is a significant connection between Ravel and Russian music. Rimsky-Korsakov, inspired partly by Liszt, started experimenting with symmetrical interval relations. One of these is the dominant ninth chord which forms a palindrome of intervals: M3 m3 m3 M3 or, in C major, G B D F A. Another was the octatonic scale that Rimsky-Korsakov started using to create fantastic or 'magical' musical effects. The octatonic scale, used by Rimsky-Korsakov, Ravel and others has a couple of points of overlap with the whole tone scale used by Debussy. As you can see, the two notes in common are E and B flat. In the example below, the upper scale is the whole tone scale and the lower one, the octatonic scale:

From looking at "Voiles" we learned that the only chords that the whole tone scale can generate are augmented ones, which is probably why Debussy moved to a pentatonic scale for the middle section. But the octatonic scale has a lot more possibilities. As it contains four minor thirds, diminished seventh chords are frequent. But you also have minor chords and major chords. Ravel tends to expand the orchestral and tonal resources of Rimsky-Korsakov as we can see in his use of "polychords" built on multiple roots in his Rapsodie espagnole of 1908. Listen especially to the double clarinet cadenzas around the 2:50 mark:

Unfortunately I have to stop here, so I will continue next time. In the meantime, have a listen to this lovely piano piece by Ravel written in memory of friends lost in the First World War. Here is the Tombeau de Couperin: