I read about the four ways to play folding book music, and I wanted
to add something.

Being sufficiently bored several years ago, I wondered what music
might sound like if were played as a "mirror image".  In other words,
the music still plays from beginning to end, but the paper is now
reversed on the tracker bar which causes the bass and treble to be
interchanged.  What was note 1 is now note 88, note 2 is now note 87
and so on.

The results were disappointing since everything sounded the same:
rumbling in the bass was the inverted melody, with the treble now
keeping the beat.  I was about to forget this idea when I realized
that some rolls would be listenable -- a Bach fugue, for instance.
Then I remembered that the famous end of "The William Tell Overture"
(The Lone Ranger Theme) is a strongly rhythmic piece, so I decided to
try inverting it.

The results were hilarious, especially if you heard the correct
version immediately before the inverted version, or perversion if you
will.  I named this piece of music as "Eht Mailliw Llet Erutrevo".
If anyone knows of other pieces that can be enjoyed inverted, please
write in.

Randolph Herr