Starch paste on historic embroidery

I have recently been working on a coverlet c. 1700 (English) and a
decorative apron c. 1730's (also English) which are both silk and
gilt thread embroideries on silk ground. Both of these works have a
brittle, grainy coating applied over the underside of the
embroidered areas that has tested positive for starch. I was
wondering if anyone has come across similar material as I would like
to know why this was carried out. My guess is that it was used to
keep the embroidery threads firmly in place so that they would not
get pulled or displaced with use, but wondered if this was correct.
If anyone has any information on this topic it would be greatly
appreciated.


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                  Conservation DistList Instance 19:28
                Distributed: Tuesday, November 29, 2005
                       Message Id: cdl-19-28-019
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