In hunting leaks and testing materials you may have use for a simple
low-rate air flowmeter you can make yourself.  For a definition of what
is flow resistance and a description of the meter, see

    http://mmd.foxtail.com/Tech/

Johan Liljencrants

 [ Johan says that he is working on a new drawing which will depict
 [ the formulae graphically.  The new drawing will be added to his
 [ article when it's finished.   -- Robbie