Odor of British Museum Catalogue

Does anyone have an explanation for the distinctive odor of the BMC?
There has been a discussion about this on the ExLibris list, but without
explanation.  The Blue British Museum Catalogue has a strong smell.  So
does the same institution's <The Lumley Library> by Sears Jayne and
Francis R. Johnson, issued in 1956.  My guess is an adhesive in the
spine.  Can anyone name it?

John P. Chalmers

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                  Conservation DistList Instance 6:33
                Distributed: Thursday, December 17, 1992
                        Message Id: cdl-6-33-013
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