Engineers against water: The case of the aljibes in La Cabaña fortress in Havana

The mastery on geometry, algebra, and trigonometry by military engineers during the modern fortification period is undeniable. Conversely, their constructive knowledge and its actual application on building sites were sometimes questioned by its contemporaries. The case of the reparation of the aljibes (water cisterns) of La Cabaña fortress, in Havana from 1776 until 1784, gives an in-depth glimpse to the understanding of the constructive techniques and materials that military engineers like Luis Huet and others who were part of the Real Cuerpo de Ingenieros had. This study uses as primary source the correspondence between Huet and General Captains of the period, as well as letters of these figures and the Ministry of Indes that touched the theme of the aljibes in La Cabaña. In addition, one of the most influential treatises on military architecture was reviewed looking for descriptions of building methods for water cisterns to compare them with the solutions proposed in Havana. To be able to rightfully understand the techniques cited, it was necessary the consultation of glossaries offering the correct meaning of the used terms during the studied period. By reviewing all these documents, it was seen that military engineers working in Havana at the time had practical knowledge that was beyond broad constructive and structural principles. They had a deep understanding of the different mortar types and their application, as well as the capability to design detailed constructive sequencies for achieving the correct functioning of the aljibes. Furthermore, it was seen that despite a direct relation between the instructions given in Cuba and the text on the reviewed treatise, there was an adaptation to Cuba’s conditions and materials.