"Dave" wrote in message
...
On Thu, 21 Jun 2007 19:09:54 -0400, "Wilbur Hubbard"
said:

And what makes you think this is true? The concentration of oxygen
remain essentially unchanged with altitude, at about 21%.

Tell that to a Mt. Everest summiteer who'd pass out without his
bottled
O2..

Ah, another candidate to sit in the corner with the pointed hat on his
head.

Now, get out your science book and look up "partial pressure."

OK, OK. You're right for once. I looked it up and the relative
percentages of the atmospheric gasses remain the same with altitude
until you get very very high up like in the ionosphere.

But, for example, the atmosphere atop Mt. Everest is about 1/3 the
pressure as at sea level. And, even though the oxygen content remains
about 23%, the available oxygen molecules to breathe are only about
1/3rd as many. So, my Mt. Everest example still holds true because 1/3rd
of 23% of oxygen (the standard amount at sea level) is still only 1/3rd
enough.

http://www.adlers.com.au/oxygen.php

Wilbur Hubbard