Octagonal work order labels

We occasionally find octagonal paper labels on the backs of the
stretchers and frames of canvas paintings.  The labels consist of a
paper rectangle with the corners cut off.  They are handwritten and
have the letters 'W.O.', which I have always assumed stands for
'Work Order'.  There is usually a string of numbers and sometimes a
date.  Only the last two digits of the year appear on the labels,
but the dates are mostly twentieth century, as far as I know--they
are sometimes written in ball-point pen.  I believe that these
labels are probably associated with one of the larger picture
restoration companies active at that time.  Another possibility is
that they are associated with a firm of dealers who commissioned
restoration work, although I have seen one on a painting that I know
has never been bought and sold (although it has been restored
several times) since it was brought to this country in the
seventeenth century.  Can anyone tell me who used these labels?

If you would like to see a photograph of a typical example, you can
contact me direct at ruth<-a t->ruthbubb< . >co< . >uk

Ruth Bubb ACR
Ruth Bubb Ltd
63 Main Road
Middleton Cheney
Banbury OX17 2LU
UK


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                  Conservation DistList Instance 28:13
                  Distributed: Friday, August 29, 2014
                       Message Id: cdl-28-13-016
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