The measure in the reading of the Romanesque churches of Pistoia

Abstract

The ancient built-up area inPistoiais dotted with Romanesque churches that, with their facades covered with white and green inlays, make the ancient streets a view into the Romanesque style . This heritage, studied in the past from an historical point of view, has not been given the due importance inTuscany. The case ofPistoiahas always been underestimated, if compared to the neighboring towns ofPisaandLucca. The survey and thorough study of these handmade works highlighted an unexpected socio-cultural environment capable of relating to the great issues in history.

The research is based on accurate surveying carried out through the latest technologies. Direct surveying was supported by a total station survey in order to map a close mesh of dots so as to describe all the components of the architectural structures examined. No laser scanner was required since such architectural works do not consist of complex architectonic systems that require its use. Modern surveying and graphic rendering technologies have been essential for working out the graphic drawings (plans, elevations and cross-sections) on which exact analyses could be carried out in order to find out the processes according to which these handmade buildings were designed and built. By overlapping grids and simple geometric constructions, on the basis of plane geometry calculations, the drawings showed the logic processes that produced these monuments, as the expression of a cultural context well above what the early medieval society ofPistoiahad been supposed to be according to the simple documentary analysis.

            The design system shown is based on high mathematical principles which allow all features to be related to a single, simple scheme, easy to remember. Those aspects, which are codified today according to the modern language and seem to be disconnected, are on the contrary strictly related to one another by geometries and numbers typical of the early medieval period. Plans and elevations reveal hidden numbers and geometric systems referring to infinity principles, double area square expansion, buildings that easily allowed the builders to estimate the amounts of the materials required. Besides these technical aspects, the medieval culture aimed at approaching the divine magnificence through numbers, by building such architectural works. Knowing about the world and the mysteries it represented was the issue being mostly tested, studied and debated in the town ofPistoia, too. Towns ofLuccaandPisaturn out to become travelling companions along the way of knowledge and experimentation that alsoPistoiawas going through.

            Measuring, based on numbers and geometries, is the real language for building. To know the measurement unit according to which the architectural works to be examined have been worked out is one of the main aspects. As far asPistoiais concerned, in the past several hypotheses had been worked out starting both from the documentary data and the handmade structures themselves. These hypotheses, however, turned out to be incomplete, since they were the result of a detailed study of the components but not of the handmade product as a whole. Therefore, research has been based on a backward process starting from the surveys carried out. The various architectural works were compared, and a multiple and submultiples apparatus was defined, so as to systematize all the components included in the architectural works studied. Measurement and geometry form a whole, the one supporting the other and vice versa. Therefore the research carried out made it possible to work out a hypothesis both as regards geometries that seem to be at the basis of the Romanesque architecture works inPistoia, and as regards the measurement that allows them to be defined by small and whole numbers. The case of San Bartolomeo in Pantano, that is the specific issue addressed in this article, is a clear example. Maybe thanks to more regular progress of works in the worksite or  builders’ experience, all components of this church are laid out in the space according to the measurement and geometries presumed. Starting from a unit component, i.e. the module, the whole complex can be described through a single, simple story.

The survey and its critical reading carried out this way become the access key to a new definition of the heritage ofPistoiawithin the history of the Tuscan Romanesque architecture.