Prayers and Portraits: Unfolding the Netherlandish Diptych is the scholarly catalogue accompanying an exhibition organized by its authors for the National Gallery of Art in Washington and the Koninklijk Museum voor Schone Kunsten in Antwerp, in association with the Harvard University Art Museums. Complementing the volume is a second book, Essays in Context: Unfolding the Netherlandish Diptych (John Oliver Hand and Ron Spronk, eds., Cambridge, MA: Harvard University Press, 2006), which collects writings by thirteen specialists from the field of Netherlandish art history. The catalogue focuses primarily on material, technical, and qualitative issues contextualized by format and use, while its counterpart offers “interdisciplinary” perspectives, meaning perspectives from “different fields of art history.” The books thus have distinct objectives. In approaching the catalogue as an autonomous work, I found the technical information fascinating, and the illustrations evocative and unparalleled in quality for diptych studies. The positive features of the volume are tempered, however, by reductive discussions of non-technical issues that fail to do justice to this important Renaissance art form.

The catalogue opens with two brief essays: “The Diptych Format in Netherlandish Painting” and “Material and Technical Aspects of the Netherlandish Diptych.” The former covers more territory than its narrow title suggests; some of these issues will be discussed below. The latter lays out the scope, methods, limitations, and general conclusions relating to a series of technical studies that formed the basis for the exhibition. In all, twenty-five paired panels, fourteen single panels that likely once belonged to diptychs, and one independent panel that the authors believe influenced Netherlandish diptychs were assembled for evaluation. The approaches employed include infrared reflectography, x-radiography, dendrochronology, and inspection with a binocular microscope. A range of exciting new findings emerged from these studies, in some cases determining whether two separate paintings thought to have been once the wings of a diptych (or small triptych) were in fact conjoined. To take one example, it is now nearly certain that Rogier van der Weyden’s panels of Saint George and the Dragon (ca. 1432) in Washington and the Virgin and Child (ca. 1432) in Madrid were once the front and back of a single panel that was cut apart sometime later. The technical studies also revealed some fascinating information about frames and hinges, which again can help establish whether two individual panels were once paired as a diptych, and about hanging devices, which can lead to fresh insights on display. New proposals also were offered about the roles of artists, workshop assistants, and “donors” in the production process. For instance, the discovery that Jan Provost painted over the original setting in his portrait of a Franciscan monk now in Bruges—an interior complete with windows and a hearth—prompted a reevaluation of the role of artist and sitter: perhaps it was the monk, with his vow of poverty, who insisted on the change.

Sufficient expository illustrations are a must for a project devoted to the qualitative, material, and technical aspects of art. The authors took full advantage of the extraordinary resources at their disposal to exceed expectation in this regard. Every image of a diptych, whether an overview or detail, and nearly every comparative photograph is reproduced in full color, with the exception of certain technical studies that were produced without color from the start. Another plus is the catalogue’s departure from the many prior publications that reproduce diptychs without their original frames or that omit the exterior painted panels. Here both are included. This is important, since such elements often provide tantalizing clues about ownership, purpose, and use in the form of inscriptions, figures, objects, heraldry, and simulated materials such as porphyry. Certain photographic details, furthermore, reveal unusual material aspects of the works that provide evidence for display and use. For instance, the outer panels of one portrait diptych in Antwerp, only three-and-a-half inches high, were painted to simulate book covers with banded spines. The portraits may have been joined originally by a leather binding and held closed with ties along the outer edges. For a diptych in Utrecht with a Latin text on the left (the so-called Lentulus Letter describing Christ’s appearance and character) and Jesus in profile on the right, the authors provide a photographic detail of wear on the frame as evidence for use: the painting was opened and closed repeatedly while hanging from a nail. Also praiseworthy is the presentation of overviews in ways that correspond to the format and structure of diptychs. The interior panels are reproduced on facing pages which, when the catalogue is opened and closed, invoke the handling of a diptych, as does the reproduction of a diptych of the Virgin and Child and a cleric, now in a private collection, in a partially open, upright position as if displayed on a tabletop or altar. The portable aspect of some diptychs is suggested by reproducing in full scale those works smaller in dimension than the catalogue’s printing margins.

Most of the illustrations are presented within forty individual entries that comprise the bulk of the catalogue. Organized alphabetically by artist, the entries provide what one would expect, including biographical information on artists and sitters and, when known, accounts of the early history of the diptychs. Some discussion of the exhibition’s material and technical studies are also included, but at the end of the volume. Even taking the appendix’s data into account, certain conclusions inferred from the exhibition’s technical studies are questionable. Could the over-painting of a diptych’s inscription late in production, which changed the age of an unidentified male devotee from fifty to thirty, have corrected rather than caused an error? The visual evidence suggests that the man’s facial features are much younger than fifty. Was the “risqué” neckline, apparent in an infrared reflectogram of a diptych presumably depicting Mary of Burgundy, later raised on the order of Margaret of Austria, Mary’s daughter and the apparent patron of the work? This seems unlikely when so many portraits of Mary made for the Hapsburgs depicted her with an equally low neckline. Furthermore, some entries raise interesting, potentially complex interpretive issues that necessarily remain unexplored, given the limits of the catalogue format. How, for example, would a supposed diptych (or wings of a triptych) representing the unusual combination of Mary Magdalene and Mary of Egypt have “functioned in private devotion”? The abundant primary and secondary literature on these two figures, much of it interdisciplinary, would have provided a useful springboard for investigating this timely question. Equally frustrating are instances in which prior arguments on diptychs are dismissed as implausible even while many of the authors’ own conclusions remain speculative, as they sometimes acknowledge.

The most troubling aspect of the catalogue, however, is its perfunctory approach to non-technical issues, which perpetuates conventional misunderstandings about diptychs. Most glaring are the comments on so-called “private” piety. The idea of a devotee worshipping privately with a diptych became engrained in the scholarship over two decades ago, when Sixten Ringbom (in Icon to Narrative: The Rise of the Dramatic Close-up in Fifteenth-Century Devotional Painting, 2nd ed., Doornspijk, Netherlands: Davaco, 1984, 30–2) used the famous miniature of Philip the Good at Mass of ca. 1457 now in Brussels to distinguish between diptychs—which, as the image suggested to him, were used in “private” worship—and triptychs, used for public ritual. What escaped Ringbom’s discerning eye was the staging of the Duke’s “private” worship as public spectacle: Philip served as an exemplar of devotional practice for his courtiers. By extension, the portrait in the diptych before him would have functioned similarly. Unfortunately, the catalogue perpetuates this rigid distinction between public and private, even when the material aspects of certain diptychs do not uphold it. One need only consider Hans Memling’s Diptych of Martin van Nieuwenhove of 1487. At over thirty-two inches wide when opened (larger than some triptychs), this diptych certainly was sufficiently large to command attention in a household, chapel, or any other space, as it did in the installation in Washington, where it was afforded pride-of-place. The boundaries of public and private break down further once one understands that diptychs were not necessarily commissioned by the persons depicted (usually described wrongly as “donors” in the catalogue). Surely some were presented as gifts, like portraits in other formats. An issue as critical as the social implications of portraiture warrants more than cursory attention in this catalogue, especially since most of the diptychs considered include at least one portrait. Some readers, furthermore, will wonder why gender, hardly a novel issue in art history, is barely mentioned, when almost all of the works pair male and female elements in the form of husband and wife or holy figure and supplicant. Indeed, the categories of public and private have received considerable attention in feminist scholarship; perhaps the authors could broaden their understanding of Netherlandish diptychs by consulting this literature.

The catalogue’s significant technical contributions are offset by rote analyses and fundamental omissions that flatten a more complex dynamic. The book may expertly deliver what it promises, but its promises remain modest.