I believe that Gab is correct. The effect is a temporary shrinkage...hehehe

Here is a big of trivia about a big balloon. The Hinderberg didn't explode because of the gas it was carrying, it blew up because lightning hit the actual structure, jumped a gap in the metal frame of the balloon and set the material that made up the envelope on fire.

Normally this wouldn't have occurred, but the Nazi's coated the material of the airship in the same material that would later go onto be used as one of the main ingredients in jet fuel...lol

(Off topic) Question about helium So I was toking some helium filled balloons the other day at our grad ball to get the desired squeaky voice effect. I'd always seen it on TV but tried it for myself for the first time.

So in the interest of science, could someone please explain to me (as if I were a 6 year old), how this bizarre phenomenon works? Why does helium make you sound like Cpt Janeway from starship Voyager?

Thanks.