Near my brother's house in Tonopah, NV, is an entrance to an old mine from
which a strong stream of air exits. I tried to tell him that it must blow
out in the daytime and in at night as the mine "breathes" due to
temperature fluctuations. But the fact is it blows out all the time! He
says there are miles of interconnected tunnels and his opening is probably
at highest elevation. What's the explanation?
Crawford