On Fri, 19 Oct 2007 16:55:04 -0500, Robert Swinney wrote:
Did you ever hear the one "Nature abhors a vacuum." Pull the air out of anything and gravity
pushing on the atmosphere causes it (the air) to rush in. Suction really has nothing to do with it,
except that was the method used to eliminate the air. Gasses can be eliminated in other ways, such
as the "getter" in the envelope of a vacuum tube at evacuation.

Oh, agreed, but both answers are equally wrong. The reason the "air"
goes in there is because there's a pressure differential. Which in
every car I've owned for the last decade or more has been
turbine-compressed. So suction is at least as accurate as "atmospheric
pressure". Ah well, not like I'm being graded on it, and a 90% vs a 92%
is the same letter grade regardless of the scale, I think.