A Musical Offering: J.S. Bach’s Crab Cannon

And now for something a little different. . .

What we have below is a video that illustrates a cool little musical puzzle from one the greatest musicians ever, J.S. Bach. It’s the first piece from Bach’s “Musical Offering”, a collection of keyboard canons and fugues, all based on a single theme. A canon is a compositional device in which a imitation of an melodic line is played, overlapping the original melodic line. An example of a canon that everyone knows is “Row, Row, Row Your Boat”. In the case of this “crab” cannon, we have a theme that was designed to be played forwards and backwards, simultaneously. The video first shows the 18 measure long theme being playing in the conventional manner. Then the theme is played backwards. Finally, using the visual image of a mobius strip, you see that the piece is made up of the theme being played front to back and then front again while the same theme is also being played back to front to back. This is an example of why music is just so cool: from a simple germ of an idea, you can get something of great complexity and beauty. Indeed, maybe the source of it’s beauty come from the fact that at it’s heart, it’s still a simple little melody.