Relative humidity control in microenvironments

How can I safely, accurately and consistently increase the humidity
in our display cases?  My understanding is that silica gel can be
used to reduce the humidity in microenvironments, but I am not aware
of a product or process to increase rH levels. The best alternative
would be to make the humidity in the rest of the building meet the
level desired in the display cases, but this is not an option at the
moment.  (It gets pretty dry inside with our extremely cold
Wisconsin winters.) Thanks for any information, including names of
suppliers, that you can provide,

Caroline Gilderson-Duwe
Preservation Dept.
Golda Meir Library
University of Wisconsin-Milwaukee
414-229-6726
Fax: 414-229-6791

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                  Conservation DistList Instance 10:6
                  Distributed: Saturday, July 6, 1996
                        Message Id: cdl-10-6-008
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