Bubble rings?

[One Skunk Todd]

I was looking at cutoverload just now, and there is an amazing video of dolphins swimming in a tank, apparently blowing bubble "rings". How is this possible? I would think bubbles like that would collapse instantly, yet they stay well-formed for seconds on end. I just don't understand how they can be so stable.

www.cuteoverload.com

direct link to youtube video:

http://www.youtube.com/watch?v=TMCf7SNUb-Q&e

[01101001]

How is this possible?

They are part of the persistent ring vortex (http://en.wikipedia.org/wiki/Vortex_ring).

Never had a toy (http://www.zerotoys.com/newsite/action.htm) that shoots a puff of air, as a self-maintaining ring vortex, across the room? Never had a grampa who shot smoke rings? It's just something fluids do.

The toy science page (http://www.zerotoys.com/newsite/science.htm) has a simple explanation and points out the dolphin hobby.

[DyerWolf]

There is also video out there of a guy who could do that. He'd lie on the bottom of a pool, wait for the water to settle, then blow rings.

I think remember seeing him swim through one...

--Don't have time to look for the links, but its not unknown.

It is cool, however.