4 ms·

Maybe he is referring to the oxygen percentage. Thin meaning they could not go on without special breathing apparatus.

• madebylaw 17y ago
  I wonder how far ancient Egyptians could have gotten without breathing apparatus? Or have the caves changed that much over time...
  • weaksauce 17y ago
    Good point, but I would guess that the caves ecosystems are in flux over time. Another comment said something about guano being an influence so if the number of bats back then was not near the number now then it is feasible that the Egyptians could have gone further without breathing tools. That and the part of the cave that the Egyptians went down might not have been the where the present day explorers are trying to go.
• mnemonicsloth 17y ago
  The article mentions colonies of bats. If the atmosphere in the caves is toxic, it's likely due to ammonia from bat guano: http://en.wikipedia.org/wiki/Guano http://en.wikipedia.org/wiki/Guano