If you are using my text book you may have noticed my interest in hats, The photo shows part of my collection. Actually it shows all of my collection, I'm not doing so well. It started when I hinted to a Mexican student that I would really like a Mexican hat. My dad who was a Baptist minister used to do the same thing from the pulpit, that's how I got my first fishing rod. The student kindly bought me back a hat but it wasn't the sort that I was thinking of. Since then I have added hats from Nepal and of course Panama. Some years ago I made a video about Mexican hats with a friend from the Maths department (also interested in hats) after many years it has resurfaced so I posted it on you tube. Here it is.