In message , Java Jive
writes
On Tue, 01 Sep 2009 19:51:32 +0100, Roderick Stewart
wrote:

You couldn't do that now. Modern domestic gas is heavier than air.

Really, I'm very surprised to hear that. I wonder what the different
formulae were/are.

It
used to be possible to fill a huge plastic bag with the stuff and send
it floating off into the sky, but it's no fun any more.

That *has* to be a good thing. Plastic bags that end up in the ocean
get mistaken by turtles for jellyfish. They try to swallow them, and
choke to death.

But do they explode when you shove a pipe up 'em ?


--
geoff