Crucifixion Diptych (van der Weyden) that they could be the left and center panels of a triptych, that they formed either the wings or shutters of an altarpiece, or that they were intended to decorate an organ case. The train of the Virgin's robe continues onto the right panel, which evidences that the panels were intended to lay side-by-side rather than separated (as the wings of an altarpiece would have been). Art historian E. P. Richardson proposed that they were the center panel of the lost Cambrai altarpiece (executed between 1455 and 1459), a single painting now split into two parts. Art historian Penny Howell
Pisa Altarpiece panels of the altarpiece, which is the only documented work by Masaccio, are in various museums. Scholars hypothesize the reconstruction of the altarpiece based on a very complete description by Vasari. The painting contains six figures: the Madonna and Child and four angels. The Madonna is the centre figure and is larger than any of the others to signify her importance. Christ sits on her knees, eating grapes offered to him by his mother. Although he is an exceedingly babyish baby (in comparison to the babies of Masaccio's immediate predecessors, like Lorenzo Monaco or Gentile da Fabriano), the grapes are