Menda bottles

I am having problems with Menda bottles--the sort that you push down
on the lid and a small amount of solvent comes into the dish-like
receptacle under the hinged cover.  After a few months they stop
working.  No change in the bottle as such but no fluid appears in
the little dish even if you pump it 100 times.  I have taken out the
spring clip on the metal tube underneath to see if I could trace the
problem, but that is as far as I could get. They are useful when
they work and I have already sent several back to the UK agent for
replacement!

Is anyone else having similar problems? Any answers to the problem
would be greatly appreciated.

Simon Moore,
Conservator of Natural Sciences.
Hampshire County Council
Recreation and Heritage Department,
Museums and Archives Service,
+44 1962 826737


                                  ***
                  Conservation DistList Instance 17:11
                  Distributed: Tuesday, July 15, 2003
                       Message Id: cdl-17-11-030
                                  ***