Jack Jarrett wrote:The first and second parts are mirror images of one another!
Indeed! Unlike most canons, the second voice is the same as the first only backwards
This is from "A Musical Offering". I had heard that Bach improvised a lot of that work and then wrote it out later. I was told that he even improvised a 4 part fugue on the keyboard, knowing all the while that the whole thing would be invertible
and still work!
That's just beyond human...
Thanks for contributing this, Jack.