Balsams
From George Eastman House : Notes On Photographs
Sticky exudations from some trees and plants. These adhesives begin as liquids but harden into solids as the liquid evaporates. Canada balsam, also known as Canada turpentine, is soluble in benzol. Before the advent of modern optical adhesives, it was routinely used to cement lens elements. Both the Cutting and the Skaife methods of sealing collodion positives used the same technology as used in mounting microscope slides with Canada balsam. Balsams were also used in asphalt varnishes and applied to albumen and salted paper prints to render them translucent for chrystoleums and ivorytypes.[1]
- ↑ Osterman, Mark. 2007. Balsams. In The Focal Encyclopedia of Photography: Digital Imaging, Theory and Applications, History, and Science, ed. Michael R. Peres, 45, Focal Press.