1.) O.K. - Cousteau was actually an innovator of underwater habitats. He had three projects, Conshelf 1, 2 and 3. They were each at different depths, for different durations, with a different number of divers (aquanauts).
2.) Here is my buddy Bruce Cantrell with a brief explanation of Conshelf 2.
https://www.youtube.com/watch?v=3CzVM0Qtm00
3.) I visited Bruce during his record setting stay at the former La Chalupa habitat, where he stayed for 72 days. We did an underwater live webcast to school. It is a little goofy and not the best interview but FYI (my segment starts at ~20:15).
https://www.youtube.com/watch?v=JWXYX-VUmJ8&t=1294s
4.) Here's what's left of Conshelf 2 today.
https://www.youtube.com/watch?v=jrDxs4ihmoE
Plenty more info. available online.