>I have also heard the theory about arsenic being commonly used in the 19th
>Century, especially on bird skins.
>Is there a way of telling the age of a mounted skin though?

This is no theory, but a fact.  Arsenic was routinely used to treat bird
and mammal skins until well into this century.  There is a documented case
of an ornithologist who died of arsenic poisoning.  In my institution, we do
not deal with ethnographic material, but being made of bone and feather,
it was probably treated in a similar manner.  In older collections, it is
reasonable to assume that there are arsenic treated specimens present.
Gloves and probably a lab coat should be used when handling suspect material.

I don't know about determining the age of a mounted skin, but there are ways
to test for arsenic, see Hawks, C., Arsenic in Natural History Collections,
in Leather Conservation News, 2(2), 1986.  Sorry, I don't have the pages
handy.  I'm pretty sure that the deleterious effects of arsenic on health
are cumulative, so this is something that should be taken very seriously.

Elana Benamy
Collections Manager, Invert. Paleo.
Academy of Natural Sciences of Philadelphia
**Host of SPNHC '96 Annual Meeting**
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