Nineteenth Century Invention under Scrutiny: Louis Auguste Boileau’s Frame Construction Systems of around 1850

Résumé En

Louis Auguste Boileau is a renowned figure in nineteenth century architectural historiography for his pioneering role in building iron structures. The building of the church of Saint-Eugène in Paris (1854-56) even steered up a violent polemic. While defended by Michel Chevalier for its use of a new material, Saint-Eugène was strongly criticized by Viollet-le-Duc, who blamed Boileau for replicating in iron, shapes inspired by stone construction. Following the church’s completion, Boileau worked on more than ten projects of iron churches, making evolve frame solutions or experiencing with other new materials such as the Coignet concrete he employed in the church of Sainte-Marguerite du Vésinet (1862-65). Concurrently, Boileau also produced many theoretical writings in which he promoted his own building systems in order to renew architectural shapes. His inventions, drawing from skeleton construction principles adopted the shapes of “voussure imbriquée” (nested arch), “pendentif à nervures” (ribbed pendentive), and “ferme-éclairante” (ligntening truss).Notwithstanding the amount of new systems Boileau produced, their originality is often blurred by a complicated writing style. The aim of my presentation is therefore to address the issue of the relationship between Boileau’s theoretical reflection and practice by establishing the specificity of his systems through the comparison of graphic analysis. By doing so, I intend to question the underlying doctrinal motives that led Boileau to such divergences between his theoretical inventions and his actual practice. The explicit reference to Gothic architecture deserves here a special attention. Even though, Boileau claimed a direct influence from this period, his proposed solutions hardly seem to derive from it. They rather seem to stem out from a form of hybridization drawing on from multiple influences and permeable to diverse historical and scientific models. The peculiarity of the systems expressed in Boileau’s writings - between scientific, technical and historical imaginary– attests to the complexity of the status of the metal framework in nineteenth century architecture.