Air trap?

[Bluenoser]

Is there anyone familiar with an airtrap? I don't know the real name for it but I've been interested in creating some sort of underwater airtrap for snorkeling. I figuire that I don't need to waste air and energy surfacing when I need to spend a lot of time on the ocean floor. Yesterday I saw a picture in the new National Geographic swimsuit issue (?) of such a device where you can just go to a sationary dive bell on the floor. I'm looking for more info in making one of these things actually work, and work well. Please reply if you have any info,
Thanks

 

[zipy]

hi

The idea is not bad. But it has some problems:
1.the air would be at the same presure as surounding watter breathing that air would mean decopresion stops (ain't good for freedivers)
2. you would have to be cearful when surfacing air could overpresure your loungs (you could die -- no good)
3.if not conected to the surface (by some sort of a tube), still limited air suply (CO2 levels could get dangerosly high)

But if proper ventilated.
It would be heaven below the sea!!!
Sorry
I don't know how it could be done to be simple (easy to build)cheap and portable. :head

Just some of my thoughts.

Zipy

 

[DiverD]

Ventilated dive bell

I think the correct term is Dive Bell. Its an ancient device. If it was ventilated, I think the water would rise to the top of the vent (the surface) and so water would have to be pushed down the vent to allow an opening, this means, again, compressed air. Sounds like you need to be hookah diving, which is probably not much like free diving.