On Wed, 21 Jan 2009 19:25:39 -0500, Tman
wrote:

wrote:
In
the carb, one-half the density should then cut the pressure
differential and therefore fuel flow by one quarter, which will give
us a mixture twice a rich as when we took off.
At the risk of dragging on the subject ... Wouldn't that actually lean
it out, requiring one to compensate by richening the mixture at higher
altitudes? One-half the density i.e. one half the mass airflow at
constant velocity, fuel flow by quarter... sounds like that mixture is
leaner!

totally correct. you richen the air in the mixture by reducing the
fuel.