Originally Posted by Out of the Box
Hollow Earth, as shown in the sketch, is supposed to be huge and connected to the atmophere by the polar holes. I see no reason why breathing would be an issue.
Maybe it was Charles Bronson's home brand mustard gas that filled that escape tunnel. But we are talking about DEEP underground. It seems the deep air is denser. Perhaps that is conducive to brain growth etc. Coming upstairs would probably feel like hell, if you lived underground for long enough. THAT'S why the reptiles drink blood! To get more blood cells.
sounds like bullshit, but then It was of my making.