Mattoni 'a zeppa' nella Ferrara del XVII secolo / The use of wedge-shaped bricks in the XVII century Ferrara

The empirical experience, on the contrary to scientific knowledge, do not aim to discover the causes of the natural behaviour of materials, but only to choose the right materials that properly perform to a specific purpose: the lack of causal explanations imposes to the empirical practice the strict application of what has been acquired and transmitted as "rules of art" by the corporation to which they belong. The paper introduces the first step of the research carried out by the author in the investigation of XVII century brick masonry in Ferrara, according to the requirement for examining so many synchronic variations identified, by setting the study with regards to the historical building tradition, the constraints imposed by the production of materials, and the guilds of the period. This survey highlights the case study consisting in the use of wedge-shaped bricks in the eighteenth-century building site of the Oratorio della Buona Morte in Ferrara that well represents the close link between historic construction techniques and artistic expression that characterizes every architectural expression and affects intervention strategies for its conservation.