collections throughout the world. The connections between the sections of
the altarpiece were made by means of lateral dowels and an ingenious sys-
tem ofinterlocking battens, possibly pegged with wood dowels (Fig. 26).^36
Two other rare examples of panels with intact, original, interlocking
battens can also be cited: a small altarpiece by Bernardo Daddi, dated
1344 (Spanish Chapel, Santa Maria Novella, Florence), and a polyptych by
Taddeo di Bartolo, dated 1411 (Pinacoteca, Volterra).H O P-M T C I 127Figure 24
Schematic drawing of a typical dovetailed
crossbeam with rectangular cross section.
Figure 25
Schematic drawing showing typical fitting of
dovetailed crossbeam with trapezoidal cross
section. Crossbeams were often tapered to
provide a snug fit.
Figure 26
Ugolino di Nerio, fragments from the Santa
Croce Altarpiece,National Gallery, London.
Drawing showing the construction of a verti-
cal unit of a polyptych.