This is the history of the research done in the late 1930s and during the war on the effects on people of breathing different mixtures of oxygen, CO2 and nitrogen. This is with the intent of studying how people going at debts underwater. It was already known that coming up from depths too quickly caused the bends, but why this happened was not known. This was particularly important during the war as the leadership wanted to be able to scout beaches before sending in invasion troops. This resulted in what would become scuba gear, but a very early and crude version.
This also had implications for submarine crews and the development of mini-subs that could be used for spying. It is interesting that the scientists doing this research used themselves as the test subjects. They were of course very eccentric and quirky people, but definately pioneers. The title refers to the 'chambers' that they had access to that would simulate people going to depths.
