I should have stated in my initial inquiry about finding a suitable
solvent for rubber cement that I am treating secondary Ampico pouches.
Until I can get to Mexico I am using Ronson cigarette lighter fluid.

John Farmer and others questioned bleed size when dealing with pouches:
"It almost seems that sealing first, and being prepared to enlarge
bleeds (which are usually 'get-at-able') is the easier option."

The bleed for the secondary valve is in effect the large vacuum supply
from the primary valve.  This gives a great deal of latitude in
tolerances in secondary valves.  Under this arrangement the length of
the tube from the primary to secondary valve would be a consideration,
although not a significant factor.

However the resistance to air flow was taken into account in a book
written about pipe organs when tubular pneumatic action was all the
rage.  I have looked in vain for this book that was in the Portland,
Oregon, library.  I was too young to understand the math involved at
the time.  The writing gave actual numbers to tube size (lead organ
tubing was usually at least 1/4-inch id, or more), tube length, wind
pressure and pouch size.  Lengths were sometimes 20 feet or more making
a triplet very chancy.

My continued search at University of Washington library turned up
nothing on organs, but led to some interesting Russian work using
pneumatic machine controls, with numerous illustrations, but all in
Russian.  Another book noted that a calculator was made in Russia that
employed pneumatic action.  How fun was that?!

Thanks again for all the information readers have sent me.

Bill Chapman,
in La Quinta, Calif., in the high 80s, 13 degrees below average!