You thought you only had one didn't you? Nope. You have four, which is what this nifty video reveals. Of course, this puts a whole new spin on your teacher's instruction to "breath from your diaphragm." You can now say: "Which one?"
Of the four diaphragms in the body, perhaps the least known is the one which moves the bones of the head. How to get a feel for this? I am reminded of the Old School teaching of Margaret Harshaw, who instructed her students to breath as though through two straws from the upper lip to the center of the head, the idea being that the breath went up before going deep into the body. Of course, it sounds like a nutty idea. After seeing this video it makes perfect sense.
Many thanks to my Facebook friend and colleague Katherine Goeldner (a most excellent Carmen) for posting this information.