I don't have a pic, and in fact I haven't seen one of these since the 70's so I'll do my best to describe it. Back in the 70's the other guitar player in our band had a unique-sounding whistle. It looked very similar to what is called a "London Police Whistle" - a short brass tube with the hole at one end that you blow into, but this one also had a small chimney at the far end. This chimney was covered with a sort of fan/cover that would spin when you blew the whistle, modulating the sound sort of similar to the way a Leslie speaker works. The harder you blew the whistle, the faster the "fan" would spin, allowing some interesting sounds. He ddin't remember where he had gotten it other than "some music shop in Chicago" and I never saw one anywhere, even at that time. I have seen neither the whistle nor the guitar player since the 70's, and I have done several Google searches but haven't found anything about these whistles - probably partly because I have no idea what the correct name for it would be (I always called it a Leslie Whistle) Here is some audio of it being used on Bob Dylan's Highway 61. It is used at the very beginning of the song, and also at the end. So does anybody know what this was called, or any other info on it?