Thin sections of waterlogged wood

Howard Wellman of the INA-Egypt inquired about how to make permanent
wood thin-section slides.  I have done this by allowing the sections
to air dry on the slide.  Once dry, cover the specimen with a cover
slip and introduce the mounting medium to the edges of the cover
slip so that it flows inward into and around the specimen.  It takes
a little practice to get the medium to the right viscosity so that
it will flow under the slip by capillary action and to drop the
right amount on the slide so that it does not flow out the opposite
edge.  I have used Permount (Fisher) and Pro-Texx, both of which are
soluble in xylene and toluene.  I would suggest using B-72, since
the properties are well known and you are familiar with it.  I
believe that Canada balsam will yellow and embrittle over time and
is not considered a conservation quality mounting medium.

You might want to contact J. Thomas Quirk, Ph.D.., who is a
specialist in wood identification for his opinion on permanent
mounting methods. He is in Madison, WI (117 North Franklin Ave.,
53705) and his phone is 608-238-2225.  I don't have an email address
for him.

Paul S. Storch
Objects Conservator
John and Martha Daniels Objects Conservation Laboratory (JMD-OCL)
B-109.1, Minnesota History Center
345 Kellogg Blvd West
St. Paul, MN  55102-1906
612-297-5774
Fax: 612-297-2967

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                  Conservation DistList Instance 11:46
               Distributed: Wednesday, November 19, 1997
                       Message Id: cdl-11-46-005
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