An Engraved Architectural Drawing at Santa Maria in Aracoeli, Rome

The use of tracings-drawings engraved on floors or walls showing an architectural detail to scale-was an important stage of the Gothic building process. Although examples of such engravings have survived all over Europe, very few Italian tracings are preserved. Two hitherto unknown examples, found in the Roman church of Santa Maria in Aracoeli, are presented here for the first time. One portrays the profile of a small base and was probably a trial drawing. The other is a two-light-and-oculus tracery pattern, and is particularly interesting because it is drawn to full scale and was cut into a reused slab of ancient marble. In this essay, I reconstruct the geometric process of generating the design and analyze the position of the tracing, with its peculiar Roman features, within the European Gothic context. I also consider the engraved drawing's possible function (guideline for template- and stone-cutters, or slab from which the tracery was to be cut directly), destination (sepulchral monument, window, or ciborium), and dating.