The principle is the same with a swazzle. This is a device used by Punch and Judy 'professors' to make the harsh voice of Punch. They pop it in the mouth between the tongue and the teeth, and can move it around so the voices of the other characters can be made too. It's a reed type of a thing. Sometimes the 'professor' accidentally swallows it, and attaches a piece of thread to the end so it can be retrieved to save him from choking! When Punch says, "That's the way to do it!" in that weird voice, it's because of the swazzle.