Arethusa

UTI ORDO POSTULAT: THE ARRANGEMENT OF MATERIAL IN DE ARCHITECTURA

At the beginning and end of books and major sections of de Architectura, Vitruvius consistently reflects on the order in which he presents his material, as in the following passage from the ending of the second book (2.10.3):² “Since then the provisions [of building material] have been explained, in the remaining books, the buildings themselves are set out. And first I will describe in the following book, as order demands (uti ordo postulat), the temples of the immortal gods, their symmetries and proportions.”³

Here and in numerous other cases, Vitruvius helps his readers to navigate the treatise, explicitly stating which material has been treated up to this point and which will be treated further on.⁴ In doing so, he regularly stresses that the design of his treatise follows a particular ordo. It is apparently this ordo which at this point “demands” the treatment of temples or, at another time, constrains the author to treat building materials first, [End Page 183] before actual buildings, or the training of the architect before either.⁵ In the face of these pervasive references to an ordering principle, it is startling that Vitruvius never makes explicit what the ordo of his treatise actually is. There is an insistent appeal to a logic behind the order of the material, and yet this logic remains unexplained.⁶ I argue that this implicit structuring principle is nevertheless crucial to understanding the treatise’s literary design and architectural theory.

It has been little appreciated to date that on the macro level, Vitruvius presents his material in the order in which a city is, or might be, built from scratch.⁷ After the training of the architect, he begins with the choice of the best possible site for the city (1.4) and the laying out of walls (1.5). The basic plan of the city is also decided on: main and side streets, the sites of major temples and the forum (1.6–7).

After the stage of planning and measuring, Book 2 concerns the choice and supply of building materials, adapted according to local availability. In Book 3, construction begins on the public buildings, whose sites had already been decided on at the end of Book 1: first religious buildings (Books 3–4), then civic (Book 5). Shortly before the end of Book 5, Vitruvius sums up the first half of his work (5.11.4): “I have described in full what appears to be necessary within the walls, and how it should fittingly be laid out.” The bare bones of a city, those features which make a city a city, are now in place. After a short discussion of harbours, Vitruvius then turns to the construction of different types of private housing, again stressing the importance of building in a manner that is suitable to the specific social and climatic conditions (Book 6). Finally, those buildings are also adorned and decorated appropriately (Book 7).

Even the final books of de Architectura, sometimes considered strange additions to a treatise on architecture, are framed in such a way [End Page 184] as to conform to this macrostructure of city construction (pace McEwen 2003.283). In Book 8, the future flourishing of the city is assured by supplying it with water (8.3.27): “Following their [a number of Greek writers on water] beginnings, I have fully described in this book what I thought was sufficient regarding the different types of water, so that on the basis of these remarks, people would more easily be able to choose sources of water from which they would be able to lead springs to cities and towns for use there.”

Book 9 concerns the astronomical and physical principles behind different types of sundials and clocks. Again, these are explained so that clocks may be put to practical use (9.8.15): “As clearly as I could, I have described the methods and practices that exist for calibrating clocks, so that they will be more convenient to use.” Finally, Book 10 (on machines) deals with...