T
of wood to environmental
conditions presents special problems for the conservation of panel
paintings. Occasionally the construction and history of particular
paintings have resulted in excellently preserved objects. Unfortunately,
splitting, warpage, and insecure design layers of many panels have justly
inspired concern for their stability.
Ideally, environmental control provides the least intrusive and best
protection. This is not always possible, or it can sometimes be only par-
tially achieved. Allowing an unencumbered panel to react with dimen-
sional and conformational changes can prevent imposed stresses, but the
movement itself can result in an unstable design layer. Moisture barriers
and enclosures can reduce these changes, but in many cases it may be nec-
essary to consider various forms of restraint and reinforcement to stabilize
the panel structure. The discontinuous reinforcement of cradles and vari-
ous batten systems has the disadvantage of allowing the panel to react to
environmental change and subject it to unevenly distributed stresses.
Reinforcement, which provides a continuous and uniform support, can
take several forms. The complete transfer of the design layer to a new sup-
port has often been accomplished. Success in stabilizing and adding dimen-
sional security has been reported for a partial transfer system in which the
panel is substantially thinned and mounted on a more dimensionally stable
support (Suhr 1932; Tintori and Rothe 1978).
Another approach gre wout of work done at the Fogg Museum of
Art of Harvard University in the 1930s and 1940s; this approach was devel-
oped by Richard Buck into the balsa-block backing that has been used suc-
cessfully for many years. This system is intended to provide structural
reinforcement, a moisture barrier, and some mechanical restraint of the
panel, while keeping the alteration of the original to a minimum (Buck
1963, 1972; Spurlock 1978).Under the direction ofGeorge Stout, the conservation program at the
Fogg Museum of Art made many important contributions to the treat-
ment of paintings, not the least of which is a treatment policy that
stressed stability through removal of aspects of insecurity and addition
of uniform reinforcement where necessary. David Kolch has provided
an invaluable review of the development of this treatment approach and
its results (Kolch 1977, 1978). He was able to compare the artworks’Treatments at the Fogg
Museum ofArt, 1927–1952289James S. Horns
Richard Buck
The Development and Use of the Balsa Backing
for Panel Paintings