Cleaning and degreasing animal head mounts

I work with the Royal B.C. Museum as preparator in the Bird/Mammal Lab
where there are a number of elderly (circa 1900 - 1940's) specimens with
grease burn and dust build-up on feathers and fur.  Having done very
little conservation work on old mounts I would appreciate any
information on the subject from anyone in the know.  There are a number
of white furred and feathered specimens ( Snowy Owl, Mountain Goat head,
etc.) which are now a wonderful shade of grey due to smoke and dust
build up.  How can I clean these specimens in particular without
destroying them?  I've used peroxide and hair bleach in the past with
varying success.  Also there are old tanned hides which are grease
burned and fragmenting, possibly from the tanning process itself.  Thank
you,

Jim Fielding

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                  Conservation DistList Instance 8:64
                Distributed: Thursday, February 16, 1995
                        Message Id: cdl-8-64-010
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