Frames and supports in 15th and 16th-century Southern Netherlandish painting

MASTERS AND MASTERPIECES: the ghent altarpiece 203 The curved parts had a specific role to play. Not unlike the diagonal cross-bars found on large wooden gates, they deflected the weight towards the hinges and the centre of the altarpiece (dormant and carrying part) (figs. 104-105). The asymmetric positioning of the double splice joints for the Angels (Singers and Musicians) supports the hypothesis of this deflection function; the splice joint closest to the hinges between the centre carrying part and the wings is each time situated lower that the other one. To counter sagging, the weight was deviated by the curved upper rail to the bearing hinge, thereby diminishing the downward pull. There was an alternation between the floating centre rail, assembled to the stiles, and the upper curved frame pieces pegged to the panel. This alternation maintained a mobility of the carpentry items that would counter or absorb the splaying force exerted by the weight of the wings. As we have seen, the desire to support the large wings and to prevent their sagging even when the altarpiece was closed had led to their being pegged to the centre of the altarpiece. The rounded shape of the wings of the upper altarpiece has often caused astonishment because not corresponding to the straight lines of the central part. Erwin Panofsky thought the Angels were originally independent works, then “cut to Fig. 104. The curved upper rail rests lower on the stile to the right than to the left. This asymmetry is intentional, aimed at deflecting the weight towards the hinges and weight-bearing stiles. Medieval carpenters regularly used this construction principle. The large wooden gate, to the right, of familiar appearance, applies a similar system. The diagonal cross-bars deflect the weight towards the hinges and the carrying masonry. Fig. 105. The curved part of the smaller wing, pegged to the panel, allowed a certain play of the construction by the diagonal cut of its edge resting on the stile.