The following is in the key of C maj. In most cases the accidental associated with the start and end of each tree that makes up the scale is the natural sign, which is what we would expect. However, if you look at the start of the third tree in the composition (5/4 → 4/3) you'll notice that the E does not have a natural sign as its accidental. This is because notes are placed on the staff according to the conventions of equal temperment. The justly intoned E being played here has a frequency of 654, whereas in equal temperment it is 659.26. The difference in cents is about 13.8 which is enough for its accidental to be a microtonal one.

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