If analysis of the wood used to construct supports can be a significant additional factor in the identification of works of art, examining how the supports were constructed can likewise provide interesting, albeit much more limited, information. Respect for the work of art means it is not always possible to examine its construction in detail, and this kind of study is further complicated when alterations have been made to the back of the panel. This led us to exclude numerous supports of dubious construction and to retain only those whose reverse sides are incontrovertibly original. Contracts and guild regulations add precious information to our often too fragmentary observation of the backs of the works themselves. Medieval iconography similarly provided interesting documentation on the woodworking trades and the tools they used.1We are extremely grateful to Marcel Maget, conservator at the Musées Nationaux and director of the Laboratoire d’Ethnographie française, who kindly allowed us to use some of the photographs of miniatures from the Fonds Olivier de Serres (Figs 52–67), which he took of a selection suggested by the late A. Van Moë, librarian at the Bibliothèque Nationale, for the exhibition Les Travaux et les Jours (Paris, 1937).

There are frequent references in the Middle Ages to perfection in woodworking. Labarte states that French and German sculptors set out to produce work of such finesse that a magnifying glass is often needed to make out all the details.2Labarte 1864–1866, I: 320. A similar concern for perfection is found in the Low Countries during the 15th century.3Labarte 1864–1866, II: 505. Contracts awarded to the painter Luis Borrassà in Barcelona in 1392 and 1396 refer repeatedly to this pursuit of quality:4Madurell Marimon 1950: 89, 91, 95, 114. the parties are required to produce ‘fine work’ and ‘good workmanship’. The materials mentioned are generally qualified using words such as ‘good’ or ‘well’: the cross-bars must be good, the nails well placed, and the wood of good quality and well seasoned.5Madurell Marimon 1950: 45, 61. Editors’ note: Véliz 1998a, 1998b; Bisacca and Castelli 2012.

It is somewhat surprising that contracts should have stated the desires of a demanding clientele quite so explicitly, since we know that the woodworking guilds’ own regulations were already very exacting. Just as painters had to comply with their clients’ demands and follow their artistic and technical instructions, so the output of woodworkers was highly regulated; they faced penalties if they failed to meet the requirements imposed contractually or by the rules of their guild. These penalties were severe, with fines ranging from 2 sols to 3 livres parisis.

The 1476 statutes of the Paris woodturners state the following: ‘[If] the said piece of work is not fit to be sold, the worker who made it will be obliged to do it again well and properly in good wood, and also to pay a fine of five sols parisis or such other sum as appropriate and as recommended by the said sworn men according to the price of the said piece of work, and to pay this fine to the benefit of the fraternity and standard of the said craft.’6Arch. Nat., Y7, f° 77–79. The king generally received the largest share of such fines. In 1487 the statutes of the carpenters and joiners of Angers specified a 20 sols fine for an infringement, to be distributed as follows: ‘Half to the King, and with respect to the second half, 7 solz 6 deniers to the fraternity and 2 solz 6 deniers to the guild’s sworn men and wardens.’7Ordonnance des rois de France, vol. XX, p. 17.

It was not simply a question of paying a fine – the offending craftsman also had to put the shortcoming right. This is expressly stated in the municipal statutes for Noyon in 1398,8Fons 1841: 23, note 1. and the same applied in Paris.9Ordonnance des rois de France, vol. XX, p. 610. In some cases, guild regulations stated that a piece of work that infringed the rules was detrimental and should actually be burned. Under article 2 of the statutes of the Paris huchiers, for instance: ‘Anyone found doing the contrary will forfeit the work, which will be burned in front of his house as false and bad; and will furthermore pay a fine of 20 solz, of which the king shall have 14 solz and the sworn men of the said guild 6 solz for their trouble.’10Ordonnance des rois de France, vol. XX, pp. 609–10.

Before we examine these historical texts in more detail, to see which infringements were punished with such onerous fines, we would like to say a few words about the history of the altarpiece, its composition and the origin of the name plate-peinture.

The term used in France from the 13th century onwards to describe a painting on a wooden panel was an ouvrage de plate-peinture (painting on a flat surface). Documents from the late 13th and early 14th century that refer to tableaux and retables can therefore be ambiguous, as the works in question could either be polychromed carvings or paintings as such.11Dehaisnes 1886, II: 555. According to Dehaisnes, the Entombment by Jehan d’Orléans is one of the earliest plates-peintures. The description in the bill of sale for this painting dates from 1383 or 1384.12Dehaisnes 1886, II: 492. The panel cited by Dehaisnes (reference Louvre, no. 876, Cat., French School), is the Pietà known as the Large Round Pietà, from the Dijon School, formerly attributed to Jean Malouel. It is included in the Brière catalogue as number 996. The number 876, which Dehaisnes gives, corresponds with the Tauzia catalogue. Cf. Painting index, no. 175. The term is likely to have persisted for some time after that. It is indeed found in a 16th-century legal document in Lille, which refers to ‘an altarpiece with four plate-peinture panels with vermilion borders’.13Dehaisnes 1886, II: 177. The structure of altarpieces, as well as the terms used to identify their individual elements, changed over the centuries. They did not always have wings (volets), which were rather unusual before the end of the 15th century.14Editors’ note: It was perhaps unusual to mention them but the winged altarpiece was an increasingly common format; see Williamson 2004. It is only in the late 15th and early 16th century that wings begin to be mentioned in contracts.15Labande 1932, I: 55. Article 4 of the 1338 statutes of the painters’ guild in Ghent states that: ‘Any painter belonging to the corporation will work with good colour on stone, canvas, and panels with wings or without.’16Dehaisnes 1886, I: 329.

According to Léon-Honoré Labande (1867–1939), an altarpiece comprised a central panel, generally surmounted by a pediment called a revers (this term, which now refers to the back of a panel, was used until the 16th century to identify the upper part); the lower element was called the predella (prédelle) as it is today; and the wings – rare before 1500 – were called ‘side panels’ (panneaux latéraux). The side panels were not, incidentally, always made of wood: when Jacques Mounier painted a three-part altarpiece for Saint-Honorat de Lérins in 1497, he executed the two wings on canvas mounted on stretchers.17Labande 1932, I: 55.

Lastly, we should also note the term ‘dust guard’, which appears in Spanish contracts dating from 1403 and 1407 to designate the wooden overhang around the sides and top of large Spanish altarpieces (Fig. 137). According to the contracts, the aforementioned Luis (Borrassà) ‘must include a dust guard all the way around the altarpiece’.18Madurell Marimon 1950: 151, 165.

Sadly, not all these altarpieces have survived to our own time: many of them have disappeared because of war, fire or obsolescence. According to Chobaut, ‘less than one altarpiece in a hundred has survived from the 15th century and less than a quarter of the contracts’.19Chobaut 1939: 87. Another reason for their disappearance is the ‘repainting of old altarpieces’. This odd practice seems to have been quite common in the Middle Ages and even after that period, through to the 17th century. On 27 July 1628, for instance, the Avignon painter Philippe Mathieu received an commission for the ‘repainting’ (repeinture) of the altarpiece of the measurers’ fraternity at the chapel of Notre-Dame-de-Paix or l’Annonciade.20Chobaut 1939: 86. As early as the 15th century, however, an inventory drawn up on 11 November 1461 refers to a painting belonging to the hospital of Notre-Dame-de-Nazareth in Avignon, showing The Virgin Mary painted on an ‘old wooden panel’.21Labande 1932, I: 241.

The perfection sought in woodworking suggests that the tools used must have been important and varied.22Editors’ note: Walker 1998: 178–85. Although we no longer know much about them, we can identify some at least by examining the surface of the wooden support, by referring to medieval iconography and by reading the few documents that have survived from the period in question. Studying the construction of the panels also tells us how advanced woodworking techniques were at the time.

Altarpieces tended to be constructed by carpenters, but they were also the work of sculptors. The altarpiece of Melchior Broederlam (ca. 1350–after 1409/11) and Jacques de Baerze (active before 1384–after 1399)23Painting index, nos. 185 and 186. ‘highlights the degree of perfection that had already been achieved in the art of woodcarving’.24Dehaisnes 1886, II: 505. The perfect execution that was required contractually and by strict guild regulations no doubt imposed working methods from which painting supports will have been the first to benefit, as we will see below.