Duty stamp

I am currently treating a painting (dated 1809) that has duty stamp
on the back. The stamp is a series of boxed numbers enclosed in a
long rectangle and reads 538|879|172|7. So far I have found one
reference to duty stamps in an article from The Connoisseur of 1932.
Does anyone know of any more recent information or research
regarding duty stamps?

Jevon Thistlewood
Painting Conservator
International Fine Art Conservation Studios
43-45 Park Street, Bristol, BS1 5NL, UK.
+44 117 929 3480
+44 117 929 3988
Fax: +44 117 922 5511


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                  Conservation DistList Instance 15:65
                  Distributed: Tuesday, March 26, 2002
                       Message Id: cdl-15-65-018
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