wood, and equipped with a flat, aesthetic cradle. Other approaches to
backing have appeared over the years. A simple gluing of a sheet of old
wood replaced a nonfunctional cradle on the reverse of a plywood sheet
in 1968.^66 Alatté, consisting of two sheets of plywood sandwiching a num-
ber of juxtaposed wooden boards, replaced a plain plywood backing in
1970,^67 while in 1975 the last thinning followed by backing was done for
the Campana Collection.^68 The choice of backing has moved toward the
most inert supports possible and thus has led to the use of so-called
marine-grade plywood, which is stronger than ordinary plywood, and to
the use of a latté (1970)^69 system, honeycomb panels, first in cardboard
(1968),^70 then in metal (1978),^71 and finally in balsa wood.^72
Whenever fixed cross-grain crossbars, nailed through to the face
ofthe painting, had caused splits, the shafts of the nails were sawn in
order to separate the crossbars and thus to remove the stress. Whenever
cross-grain crossbars inlaid with dovetails in the thickness of the wood had
to be removed because they had contributed to splitting, the gap that
remained was filled with wood in the direction of the grain to avoid the
risk oflocal weakness. Joints that have completely come apart are con-
nected with tenons and mortises one-third as thick as the panels. However,
when the joints have only partially come apart, or when the split affects
only apart of the length of the panel, the practice since 1965 has been to
replace the old inlaid dovetail tenons by V-shaped incisions of a maximum
of two-thirds the thickness of the panel, each followed by an inlay of the
same section in the same kind of aged wood. The aperture of the V has to
be as narrowas possible, so that little of the original wood is removed; at
the same time it should be wide enough to allow good adhesion at the
bottom of the V. Claude Huot adopted V-shaped incisions upon his return
from one of his trips to Rome. By 1979 these inlays were sometimes
replaced by cleats set on the reverse in the direction of the grain in the
case of splits that did not have projecting edges (Emile-Mâle 1976:21), and
by small tenons, as thick as one-third of the panel, placed at the ends of
the boards in case of simple incipient splits.
To reduce the portions of the surface given to gluing, the fixed
slats running in the direction of the wood grain of the panel were replaced
by cleats and, in later work, by half cleats to support mobile crossbars.
After 1965 the crossbars were made with hollowed-out surfaces facing theW P S: T H Y H F 277Figure 10
Master of Stratonice, La Vierge et l’Enfant
avec deux saints et deux anges.Reverse, detail.
Musée du Petit-Palais (MI 542), Avignon.
Metal crossbar composed of two U-shaped
aluminum sections and reinforced with
mahogany. This system is suited to big panels.
Figure 11
Machiavelli,La Vierge et l’Enfant avec deux
anges.Re verse. Musée du Petit-Palais (MI 522),
Avignon. Châssis-cadre system. A mahogany
stretcher for perimetric support was formed
to follow the warp of the panel. The stretcher
is secured with a brass L-shaped frame lined
with felt. A space is left between the frame
and the painting to allow for the play of the
wood.