Text versus visualization in the presentation of diachronic analyses of historical objects on the example of the Saint-Nicolas fort in Marseille

The theme of this paper is the communication of knowledge about the evolution of architectural objects. Our aim is to highlight the impact of the form of transmission and the spatial discrimination used in the analysis on the clarity and the level of understanding of the proposals made. This paper is based on the diachronic analysis of the fort Saint-Nicolas in Marseille presented in the expert report on the condition of the fort, conducted between 2015 and 2022. In the course of the research reported, a detailed analysis of the fort’s evolution was carried out according to two spatial discrimination variants: the fort considered as a whole and the fort divided into its constituent elements arising from its function as a fortification work. In order to highlight potential differences in the interpretation of the content of the report, two researchers independently analysed the information gathered in the report on the evolution of the site. The study based on a diachronic analysis model that allows for visual (diagrammatic) representation of information, taking into account the degree of perceived dating uncertainty, the number and type of transformations and their consequences for the form, structure, function and ownership status of the site. Even a cursory analysis of the resulting diagrams reveals the specificity and evolutionary independence of the different parts of the fort, as well as significant differences in the interpretation of the same data by different analysts. The article presents an analysis of the results, underlines the most substantial differences between traditional methods of communication and forms using information visualisation, and discusses the potential and limitations inherent in the method of the analysis used.