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

HINGES. CLOSING, HANGING AND POSITIONING SYSTEMS AND DEVICES 105 The arrangement of the hinges determines the rotation of the movable elements of woodwork. When an altarpiece having four wings, a pair on each side, is closed, we see the knuckles between the two wings of each pair. This results in easy opening, while the wings remain rigid together during the closing process. When a triptych is open, the knuckles are visible between the wings and the central carrying part. In general the node protrudes for half of its diameter, the other half being housed in a quadrant notch cut into the uprights of the frame. This cut is extended upwards to allow for the easy inserting and removal of the pin (fig. 57c-d). Such cuts are often roughly made, suggesting the work of the locksmith rather than the joiner. The recess for receiving the blade of the hinge is sometimes cut diagonally into the thickness of the upright (fig. 57g-h), with one or two nails then passing through the mouldings. Hinges of this type were already in use in the late 14th century. We observe them in the Triptych of the Reliquary of the Virgin’s Veil (Tongeren, BOL , no. 1 ). In rare cases, the blades can be nailed onto the top and bottom edges of the frames (fig. 57i). The knuckles are then flattened around a short flat pin. In very small triptychs, the mobility of the wings is sometimes provided by two simple inter- meshed pieces of wire or metal rod. In the 16th century we also find altarpieces with architectural frames, with the paintings embedded in a decor of columns, pediments and pedestals, which would later become typical for the Baroque period. We find cases where the wings are attached to columns by means of a fixed unarticulated bracket, nailed to the column. Here it is the column itself which rotates with the opening and closing of shutters (fig. 57j). B. Closing systems and devices A certain variety exists in the systems adopted for the proper closing of articulated works (fig. 58: 1-8). As early as the end of the 14th century we find the system of a wooden cam swivelling on a nail (fig. 60a). These then disappear from the scene, other than for holding large panels in their frames: Josse van der Baren, Triptych of St Ivo , 1607 (Leuven, SP , no. 3 ) and Pieter Claeissens, Onze-Lieve-Vrouw van het Boompje , 1608 (Bruges, OLPM , no. 11 ).