Sure, we've got the rhyme scheme that we discuss in our "Form and Meter" section, but Moore is tinkering with a few other elements, too, in the sound booth that is this poem.
One of the tricks Moore has up her sleeve is a Shmoop favorite—the awkward pause. The way she breaks (ends) the lines and arranges some of her phrases often brings us to a complete stop as we try to figure out how it all fits together.
This poem is by no means written the way we would speak. It doesn't mimic the patterns of natural human conversation, which forces us to pay close attention and adjust while we're reading. Moore isn't afraid to break lines at "a" or "it," which we would never do when speaking. This makes for a jerky, stop-and-start rhythm and sound to the poem. It forces us to slow down and consider each image, and how it might connect to the others.
And finally, what's with the honors-level vocab and cultural references? "Legion," "apteryx," "gyroscope," "unequivocal"? Scarlatti, Gieseking, Herod? Sheesh. This makes for a very intelligent-sounding poem, but it also enhances the interrupted, stop-start effect we talked about in the previous paragraph. There's a lot going on with sound, and it isn't the smooth cooing of nightingales that you find in some poems. It's the sound of a reader learning as she reads.