were noted. Because of these defects, many planks were repaired during
the original construction with the application of plugs of wood (also of
white poplar) held in place with hide glue and nails. The assembly of the
planks was achieved by butt-joining and accurate planing of the faces to be
united. Diagonal scratches were also made, to improve the bond of the
glue. Housings were carved inside the thickness of the planks, in proxim-
ity to the joins, in which floating tenons were inserted (Fig. 16).^15 These
elements of joining between the planks, regularly spaced in height on the
painting, are made of walnut and have a rectangular shape. They were
inserted without glue into the housings with the grain perpendicular to
that of the support, and held by dowels that pass through the thickness of
the planks. Three fir crossbars that tapered in length were mounted on the
back and inserted into dovetailed tracks cut into about one-third of the
thickness of the support. The panel is relatively thin for its size and under-
goes only light restraint from the crossbars. It was discovered that in real-330 Castelli
Figure 15
Francesco Salviati, The Deposition from the
Cross,1547–48. Oil on panel, 495 3 285 cm.
Church of Santa Croce, Florence. View of the
front of the panel shows the separated planks
before wood restoration.
Figure 16
Francesco Salviati, The Deposition from the
Cross. Side view of the plank, showing parts of
the original floating tenon and the diagonal
scores made to improve the hold of the glue.