Catenary arches, one of the main features of Art Nouveau architecture in Spain - a movement that includes the Catalan Modernism movement - began to be used in Spain during the first half of the 18th century. This is the thesis posited by the Director of UIC Barcelona School of Architecture, Josep Lluís i Ginovart, in the chapter “Scientific Knowledge of Spanish Military Engineers in the Seventeenth Century”, which is part of the book “Military Engineering”, recently published by Intechopen. 

The study is based on the analysis of drawings of gunpowder warehouses from the first half of the 18th century, which form part in the collection of the General Archive of Simancas. These drawings reveal that the “chain theory” - the mechanical theory that would enable the application in building of the catenary arch - arrived in Spain during the first half of the 18th century. This is demonstrated by, for example, Miguel Marin's work for Barcelona (1731) and Tortosa (1733) and others by Juan de la Feriére in A Coruña (1736). Josep Lluís i Ginovart explains, “Although there is no evidence of the construction of the gunpowder warehouses, it is possible to confirm the use of catenary arches in the construction of the Carlón cellars of the O’Connor in Benicarló (1757).” 

According to the chapter, after the Bourbon dynasty’s ascendancy to the Spanish throne in 1700, Catholic diplomatic and military families of Irish and Scottish origin emigrated under royal protection, preserving their status. Those same families contributed to the introduction in Spain of the modern mechanical techniques already existent in the UK. The chapter concludes that “The theory of the equilibrium curve became known to the Bourbon military engineers in the eighteenth century, and it was used by some Irish immigrants, such as the O’Connors, a century before the Art Nouveau architecture of Antoni Gaudí.”