Chemical sponges

I've gotten an example of the infamous "book sponge" called the Wal Brite
Book Sponge which is used to "remove soot, smoke film, mildew, etc. from
books."  This was recommended to me from several sources.  Frankly, it
does not appear to have any chemicals or residue.  It is simply a heavy
chemically-produced vulcan rubber sponge with fine pores.   Can those of
you who have used these tell me--is it simply a wipe-and-toss item?  Does
it actually have a chemical?  Do you wet it to use it?   Thank you.

Dean DeBolt
University of West Florida
Special Collections

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                  Conservation DistList Instance 6:48
                   Distributed: Friday, March 5, 1993
                        Message Id: cdl-6-48-014
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