Daddi's large Saint Paul panel has survived intact, but its form is relatively simple compared to other more complex altarpieces of the time. An example of a much more complicated engaged frame can be seen in Agnolo Gaddi's huge Madonna and Child with Saints and Angels (c. 1380/1390).
This work's pointed arches, triangular gables, quatrefoil shapes, and other decorative motifs were inspired by contemporary Gothic architecture. They were intended to enhance the sacred aura of the altarpiece and the painted holy figures when illuminated by candlelight in the often dim interiors of churches. Looking at the altarpiece from the side we can see the object's complicated construction, with two overlapping molding layers used to create the deep frame for the gables and arches, as well as the damage that insects have caused over time to some of the altarpiece's major wooden structural members. Much of what we see in Gaddi's work is original. Yet some pieces, including parts of the base and the spiral colonnettes, were made and added in the 20th century to replace missing parts that originally covered joints between the painted panels.
Duccio's Nativity with the Prophets Isaiah and Ezekiel (c. 1308/1311) in Gallery 1 has had quite a different history. Its immediate engaged frame is intact, but the work itself is only a small segment of the artist's huge Maestà (Madonna in Majesty) altarpiece that was carried to the high altar of the cathedral of Siena in a magnificent civic procession after it was completed in 1311. Perhaps the largest and most splendid altarpiece of the entire Middle Ages, this monumental work was painted on both sides with scenes glorifying Mary and Jesus. By the 18th century, however, Duccio's art was no longer appreciated, and his magnificent Madonna in Majesty was cut apart. Some individual panels were sold, including The Nativity and Calling of the Apostles Peter and Andrew (also in Gallery 1). Unfortunately, the latter picture lost its engaged frame when the altarpiece was dismantled. It now has a frame made in the last century.
In contrast, Nardo di Cione's entire small portable Madonna and Child with Saint Peter and Saint John the Evangelist altarpiece (c. 1360 ) in Gallery 1 remains intact—both the painting and the gilded frame.
The work, a triptych, consists of a central panel and two smaller moveable wings. The delicacy of the original engaged Gothic-style frame adds to the splendor and solemnity of the holy figures. When closed over the central image of Mary and the Christ child, the wings provided protection to the painted surfaces and undoubtedly contributed to the triptych's remarkable preservation. Looking closely at the outer edge of the right wing with the figure of Saint John the Evangelist, we see both the joint of the engaged frame molding and the raised lip of wood perfectly fitted to the recessed groove on the left wing when closed.
The tradition of such intimate, portable altarpieces continued into the 15th century, as seen in Sassetta's elegant Madonna of Humility (c. 1435/1440) in Gallery 3. This delicate, refined panel is the central part of a triptych that lost the two side wings originally attached to it.