ABSTRACT

The three Mathematicians’ study stood out for its important innovation. It contained an assessment based entirely, perhaps for the first time, on a scientific criterion aimed at interpreting the mechanical behaviour of an architectural building. Its historical importance lies in the fact that, unlike the previous practices, which were based on empirical rules, generally of a geometric nature (see for example Poleni’s studies on the statics of arches), theoretical conceptions, this time of a scientific nature, were used and applied to the study of a structural problem. Although not entirely correctly, the PVW (Principle of Virtual Work) was adopted in the assessment, and used as an instrument for measuring the metal rings to be applied to the drum of the dome (Capecchi, 1999; Capecchi, 2002). In an attempt to determine an important date, a number of experts (von Halász 1969) regard this

assessment as the historical moment when the change took place from engineering based on artisan traditions, of an empirical nature, to engineering based on the application of the new scientific theories; theories, which were just starting to become established.