Recherches sur la construction la plus avantageuse des digues

Charles Bossut, Guillaume Viallet, 1764

Charles Bossut (1730-1814) was a French mathematician Jesuit acknowledged as an expert on hydraulics and hydrostatics, in which he became one of the main French exponents of the eighteenth century. He was born in Tartaras in 1730, a village in the south of France. He studied at the High School Ampere, in Lyon, a Jesuit college where he began to devote himself to scientific research under the guidance of Père Béraud (1702 - 1777). In 1752, at the age of twenty-two years, he became a professor at the school of military engineering École du Génie at Mézières and collaborated with two brilliant mathematicians of the time: Leohnard Euler (1707 – 1783) and Daniel Bernoulli (1700 – 1782). There, he worked as a professor until 1769 and later as an examiner of students. Bossut was admitted to the Academy of Sciences in Paris as a correspondant in 1753.

In 1764, in Paris, Bossut collaborated with G. Viallet, Deputy Inspector of Bridges and Roads for the province of Champagne to publish the treatise Recherches sur la construction la plus avantageuse des digues. In 1771, he published his work Traité élémentaire d'hydrodynamique, based on research carried out over the years at Mezieres.

He was encouraged in his mathematical research by the encyclopedist Jean Baptiste Le Rond D’Alembert (1717 – 1783), who edited the famous Encyclopédie de Diderot et d’Alembert. In this context, he wrote the scientific section of the Encyclopédie méthodique. Also, in collaboration with D’Alembert, he published a treatise entitled Nouvelles experiences sur la resistance des fluids, in 1777.

He was the author of several works crowned by the French Academy of Sciences and his writings became a fundamental basis for the study and teaching of mathematics and some more specialized fields. Bossut was particularly interested in the problems of hydraulics. The importance of Bossut for the history of science is not only due to specialized research in hydraulics, but also to his role as a major contributor to French (and European) scientific education.

In 1775, he was called by the economist and minister of finance of Louis XVI, R. J. Turgot (1727 – 1781) to collaborate, along with D'Alembert and N. Condorcet (1743 – 1794), for a study on canals and natural waterways inland France for a development and improvement of trade. At the time, he was teaching hydrodynamics at the Ecole Royale du Génie in Mézière, but later, thanks to his collaboration with Turgot, a special chair was created at the Louvre in 1774, which he occupied until 1780. It was Turgot himself who created the special chair.

Turgot asked D'Alembert, Condorcet and Bossut to carry out studies to improve navigation within the French territory, with the aim of making trade more efficient. Bossut then carried out, in the summer of 1776, experiments on the basin of the Royal School of Engineering of Mézières to evaluate the resistance experienced by a body in motion within a fluid. The results obtained by Bossut were published in collaboration with D'Alembert and Condorcet the following year, in a treatise entitled Nouvelles expériences sur la résistance des fluids, where were reported the experiments conducted to enhance navigation within the French kingdom.

In 1786 was published by the Imprimerie Royale, the long compendium Traité théorique et expérimental d’hydrodynamique, which included both the contents of Traité élémentaire d'hydrodynamique (1771) and Nouvelles expériences sur la résistance des fluids.

Bossut's textbooks were used throughout France. The treatise Recherches sur la construction la plus avantageuse des digues is a work that was not revised by the authors before printing and underwent several changes. For this reason, Bossut and Viallet themselves published a second edition of the treatise in Paris in 1799. The work is a major hydraulic engineering effort, and the purpose of the essay is to focus on the construction of obstacles that oppose the flow of a fluid. In this way the term dam acquires, depending on the methods by which it is built, the materials used and its use, the name of embankment, piers, wharf or other.

The intent of the treatise is highlighted in the introductory chapter. Subsequently, the work consists of six chapters, an index, and a final section entitled Privilege du roi. The first chapter delves into the question of embankments for ponds and is divided into a first part of seven paragraphs of a theoretical nature and a second part of eight with a highly mathematical content. The second chapter studies river structures and is in turn divided into three sections. The third and fourth chapters deal with further specific topics (jetties and reversors) and the fifth investigates what the author calls epis. Regarding the latter, epis refers to all dams that generally have the purpose of preserving and protecting the banks of a river. Therefore, the treatise concludes with a chapter on masonry dams, which is followed by a series of explanatory pictures and graphs.

In 1800, the work Recherches sur la construction la plus advantageuse des digues was translated into Portuguese by the mathematician Manoel Jacinto Nogueira da Gama (1765 – 1847) with the title Indagaçaõ da mais Vantajosa Construcçaõ dos Diques, which was published in Lisbon by Joaõ Procopio Correa da Silva. The treatise of Bossut is included in a large editorial effort, where also appears the translation of some extracts from Belidor's work Architecturahydraulica and an essay entitled Ensaio sobre la theoria das torrentes e rios, by Jean Antoine Fabre published in 1797 in Paris. It is assumed that the treatise was published and translated with the intention of introducing Lusitanians to scientific notions that were being developed in France.

Moreover, the edition of 1764 published in Paris is available in some libraries in the Iberian Peninsula: the University Library of Sevilla, University Library of Valladolid, National Library of Portugal (BNP) and the National Library of Spain (BNE).