Works on Paper in the Tropics

I am somewhat stunned by the idea expressed by Chris Waller that
tightly sealed cases are dangerous because of the possibility that
changes in air pressure could break glass.  I guess it is true that
when I have designed and built really seriously airtight cases, I
have not used glass, but that was primarily because of practical
matters of construction.  When building a case that is as airtight
as reasonably possible (whatever that means exactly!), it may make
sense to build in one component that can act as a diaphragm to
accommodate changes in air pressure, but this is so that those
changes will not compromise seams or seals.  I would be interested
in comments on this matter.  Is there some sense that sudden glass
breaks on case fronts that are sometimes hard to explain otherwise
may have some connection to air pressure changes?

B. Appelbaum

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                  Conservation DistList Instance 11:74
                   Distributed: Friday, March 6, 1998
                       Message Id: cdl-11-74-001
                                  ***