Above: Façade of Strasbourg Cathedral (“Plan A1”), Strasbourg, France, 1260s, 33 7/8 x 23 1/4 in. (86 x 59 cm), Musée de l’Oeuvre Notre-Dame, Strasbourg, Inv. no. 2.
The so-called Strasbourg Plan A1, seen above, offers an exquisite example of medieval architectural drawings, which are rarely accessible to anyone, including scholars and researchers. It is one of the earliest surviving graphic documents of a monumental structure, authored by an anonymous artist. Although we do not know his name, the artist left us with enough information, in pen and ink, to express his vision for the design of the west façade of Strasbourg cathedral.
It was more than pen and ink that I wished to find when I approached the framed drawing for the first time. It was leaning against the wall, silently, waiting to be hanged. I knelt down and started looking for prick holes—yes, prick holes—those barely discernible marks left by the sharp point of a compass. Prick holes serve two important functions. In an original drawing, they reveal the invisible geometric forms underlying the design: circles, say for a rose window; or arcs, two of which combine to form a pointed arch for a window or doorway. Prick holes penetrating through the entire thickness of the parchment may suggest that at some point the drawing was used as a master for copying, when the sharp point of the compass or a similar instrument needs to reach the parchment below. Key details of the original drawing—for example the apex of a pointed arch, the cusps of a tracery window, or the outline of a doorway—would be pricked through. A précis, or essential summary, of the design would then be transferred onto a sheet of fresh parchment directly underneath, visible with the marks (prick holes) made by the sharp point. These marks would then serve as guides for the artist to complete the copying process. Medieval Xeroxing, one might say.
When the Strasbourg Plan A1 was removed from its frame in the studio of a restorer in Paris, prick holes were only visible on the front face, with none discernible on the back. This suggests that it might have been copied from another drawing, perhaps the so-called Plan A, which is almost identical to Plan A1 but has fewer intricate details. We know that Plan A1 belongs to a set of drawings depicting the various designs for the Strasbourg west façade, now known as Plans A, A1, B, B1, and D. None of these drawings was followed exactly when the façade was constructed, although Plan B seems to be the closest version to the main bulk as built. We know from documents that construction of the west façade began on May 25, 1277, but we do not know when the various designs for the façade were attempted. A logical and commonly accepted strategy is to date some of these designs to the 1260s and 1270s. The chronology of these drawings, and the incongruities between their renderings and the actual façade, only add to the intrigue and challenge of understanding the drawings’ history.
Anyone visiting the cathedral of Strasbourg cannot help but be impressed, if not outright awed, by the enormity of the spectacular façade. Yet, to untangle the thinking behind its design, we rely on—among other things—the tiny prick holes.
—Nancy Wu, Museum Educator, The Cloisters Museum and Gardens