Karsten tube tests on sandstone

I'm after suggestions for methods of fixing a Karsten tube apparatus
to a weathered (but flat) historic sandstone face that will leave
minimal trace (preferably none) after testing--any ring stains left
behind will be quite conspicuous.  The test will be carried out with
the sandstone in an horizontal position.

Jim Mann
Dimension Stone Specialist
Amdel Ltd
35-37 Stirling St.
Thebarton
South Australia 5031
+61 8 84165200
Direct Phone +61 8 84165328
Fax: +61 8 82342760

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                  Conservation DistList Instance 16:36
               Distributed: Wednesday, November 27, 2002
                       Message Id: cdl-16-36-010
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