Interesting info, Muttley.

From your examples though, I'd presume (correct me if I'm wrong) that once your body is so far gone that breathing and pulse aren't apparent, you'll need some pretty good medical attention to save you. Are there many cases of people coming back spontaneously?

And this might be a cheap shot, but if you're teaching history, better not teach your kids from the stories your granny told you. They may be nice stories, but... :-/

Graham.