The painting depicts the building of the tower of Babel surrounded by wooden scaffolding, on a site where carpenters, builders and stone masons can be seen. The scene shows some construction techniques from the Late Middle Ages, when many tasks were carried out on the site itself: a worker puts a container of mortar into the hexagonal tower beneath an arch held in place by a wooden centering. Putlogs, into which the horizontal beams of scaffolding were inserted, can be seen around the tower made of the stone masonry that abounded in Flanders. The mechanical nippers shown at the top of the painting transport a large ashlar using a hand-driven crane connected to a large wheel that works like a ferris wheel. This lifting machine was simple to build and could be assembled and dismantled as building progressed. Other workers are building scaffoldings and putting ashlars in position. A stonemason in the quarry hews ashlar out with a mallet and chisel, whilst another –possibly a stone cutter– speaks to a man who, judging by his dress, could be one of the works overseers. A third man works at the forge in the Hütte, loge, lodge or shop –a working area with heating– made of wood with a thatched roof.
Two main groups of artesans were involved in this kind of construction: carpenters and labourers. There were others involved in occasional tasks, such as metal workers, despite which they gradually gained a privileged position but it is beyond the scope of this study to analyse their organisation as a craftsmen’s guild. The differences in prestige and social aspects between overseers and labourers, who were the majority, was more obvious on site. They were hired at the same workplace and paid by days or for piecework. Mortar mixers constituted a higher category. The analyses of certain accounts reveal that the labourers who positioned ashlar to build walls belonged to a higher category. Stonemasons occupied a privileged position being the mandatory steppingstone between the architect or the overseer and the building site. In order to achieve a satisfactory result, the stonemason needed three essential elements: basic training, the tools he made himself, and the materials chosen.
The scaffolding consisted of a provisional, wooden structure enabling an upright wall face to be built, to which it was temporarily attached by means of sockets. This framework featured narrow walkways made of wooden boards situated at a suitable distance. The use of free-standing scaffolding was quite rare in medieval times: certain parts of buildings themselves provided support for parts of lighter, smaller structures, some of which jutted out. From the last quarter of the 12th century onwards hoisting devices came into use to raise ashlars, since this type of material could not be transported by hand, as depicted in the painting in the Hours of Joanna of Castile. From this moment onwards, certain building elements were made of solid stone.
Depicted in the foreground is the architect, overseer or magister –who can be identified with Nemrod according to a legend told in the Speculum humanae salvationis– recognisable by his measuring rod, who supervises the work and listens to the commentaries by the construction master who is pointing at the mechanical hoisting nippers. This device may have been designed by the architect since master builders, having been trained as stonecutters, were also well acquainted with carpentry, sculpture, painting and machine building. Since the relationship between the two was based on both trust and a clear, well-defined contract, painters regarded them as equals. Works management became increasingly complex, requiring specialised tasks. The latter half of the 11th century consolidated the image of the modern architect, i.e. the person requested by a construction manager to draft, design and execute a project. The image of the architect bears more resemblance to the iconographic tradition used when depicting buildings than to reality since, from the second decade of the 13th century onwards, his activity was transferred from the outdoors to the inside setting of his studio, as reflected in written documents and even images. When drawings and plans became the planning medium par excellence, a series of changes took place, the first being, as mentioned earlier, that the architect’s presence on site was no longer absolutely necessary, for he was replaced there by mid-range officers, the overseers. All the figures, except the labourers, are dressed in clothes designed to give them an oriental look. One man who, judging by his garments and lack of measuring rod, may be a labourer or apprentice that the construction master has to teach, speaks to two people that could be kings due to their head-dresses and the ermine collar worn by one of them.
Pentecost appears as the necessary continuation of the apostles’ mission and a prelude to their activities which, without this miracle, would have been impossible. Consequently, this scene marks the start, logically enough, of the narration of the Acts of the Apostles. The confusion of tongues presented in the Genesis text about the tower of Babel as a punishment for human pride, is transformed here, by inverting ideas, into a grace granted by the Holy Ghost. In the prefigurative interpretation of the Bible, the coming of the Paraclete, which endows the apostles with the gift of tongues, is compared with the confusion of languages that halts the construction of the tower of Babel. The gift of tongues granted to the apostles will reunite those that the “tower of confusion” rendered foreign to each other. Thanks to their efforts, a building will be erected which, without conceit or madness, could aim to reach as high as heaven, and instead of defying the Lord, would permit the world to be reconciled with its creator. The new, spiritual tower of grace will not be built of bricks and stone like that of Babel, a symbol of humanity’s pride and lack of moderation, but with the virtues of Christ the Redeemer .
The themes mentioned in Genesis, i.e. the building of the tower and the confusion of languages, are sometimes combined and sometimes juxtaposed. This theme has antecedents dating back to the 11th century, as can be seen in an ivory altarfront in Salerno. The construction of the tower of Babel, symbolising the punishment of human pride, has been depicted on countless occasions. In the 15th century, however, it acquired a mythical meaning as regards architecture: it was a medium enabling painters of books, panels or walls, to depict a dizzily high, stone construction, whilst also portraying the people and means that made its execution possible. Hoisting devices play a prominent role in these representations.
This parallelism between the two paintings –Pentecost and the construction of the tower of Babel– is not common in books of hours, except in certain works such as a French book of hours made in Rouen (Baltimore, The Walters Art Gallery, MS. W. 224, f. 57r) and the occasional one attributed to Gérard Horenbout, such as the Spinola Hours (ff. 31v-32r), in which the Old Testament theme occupies the historiated border surrounding the scene of Elias begging heaven for fire. It is more common to find just the representation of the descent of the Holy Ghost, the third person of the Holy Trinity, in the form of a dove or, as mentioned earlier, according to the canonical hours, different actions of the Paraclete related to preaching and baptism of either Christ or the apostles. Furthermore, the Holy Trinity and, less often, the succession of the days of creation, also appear amongst other, less frequent themes. As mentioned earlier, the Hours of Joanna of Castile was influenced by the Speculum Humanae Salvationis, the most widely disseminated book as regards this section –and the following section, i.e. the hours of the Virgin– which, although it provides certain themes uncommon in the iconography more or less usual in books of hours, was not totally alien to the Flemish spirit of the late 15th or 16th centuries, as revealed by the recto folios of the small office of the Virgin in the Golf Book. In addition to indicating the great intellect of the person responsible for the iconographic cycle, both books also reveal a desire to find a harmony between the Old Testament and the New. In the manuscript by Simon Bening and his workshop this trait was due to the obligation to abide by the orthodoxy and teaching of the Catholic Church as opposed to the free interpretation of the Scriptures by the Reformed Churches. Gerard Horenbout’s manuscript, on the other hand, maintains a tradition well-loved and immersed in the devotio moderna, since the essence of the hours of the Holy Ghost and the little office of the Virgin, as in the Speculum humanae salvationis, is the work of Christ’s redemption exemplified by typological-allegorical acts. In this instance, humanity is called upon to study the mystery of Biblical History in depth “with the eyes of the heart” (oculis cordis). As a result, in the case of the Hours of Joanna of Castile, the images complement the text and theme of meditation. Unlike the rigid typological form of the Bibliae pauperum, the method employed in the Speculum –and, consequently, in certain illustrations in the Hours of Joanna of Castile– ceases to be simply a demonstration of biblical unity and becomes part of a complete whole intended to promote spiritual devotion.