This is the first strip in which a character is thrown head-over-heels just from the force of some other action, usually a loud noise. We have had a case sort of like this back in the first Lucy football strip, but it didn't happen in the iconic Peanuts fashion. This is the first time in which it's mere noise that causes the tumble.
The head-over-heels motion will become one of the most distinctive elements of Charles Schulz's visual comic language. It looks natural on the page, but it doesn't animate very well; the implied force is away from the noise, so the subject can't stay on-screen long enough to read the motion well. Also, is the victim spinning, or just being thrown back? And what kind of sound should the somersault itself make?
