"David Billington" wrote in message
...
When I was a student one of the others on the course filled his lunch bag
with OA mix and lit it. Bang, the lecturer and others went in to see the
kid standng there dazed but unhurt. The lecturer didn't bother to tell
him off for being that stupid, he reckoned he learned a lesson and
wouldn't do it again.


He probably wouldn't have heard him anyway, just high pitched ringing. : )