"Peter W. Meek" wrote in message ...
On Tue, 17 Jan 2006 15:20:49 +0000, David Billington
wrote:

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.

The instructor in my first gas welding class was
giving the orientation lecture in a gymnasium-
sized shop. We were gathered around a steel
assembly table. While giving us the standard
safety lecture he was fiddling with a Styrofoam
coffee cup. He poked a hole with a pencil and
set it top down. A bit later he lit his torch,
adjusted for a nice neutral flame, and then wiped
the flame out. He held the flowing gas to the
pencil hole and then relit the torch. He said,
"Now, listen!" and held the torch to the hole.
Fortunately, I had no class immediately after,
because it was several hours before I could
hear clearly again.

A more graphic demonstration of the extreme
explosive power and brisance of a perfect
oxy-acetylene mix would be hard to imagine.
That was the sharpest CRACK I have ever heard,
and I have been within 50' of a lightning
strike that converted the top six feet of
a telephone pole to toothpicks.
--

Many years ago, a friend hooked a baggy to the overflow tube of a
motorcycle battery while it was charging. The resulting filled baggy was
ignited with a string/match time fuse. Similar results.

Bob