Jean-Baptiste de La Chapelle (c.1710–1792, Paris) was a French

priest A priest is a religious leader authorized to perform the sacred rituals of a religion, especially as a mediatory agent between humans and one or more deities. They also have the authority or power to administer religious rites; in particu ...

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

and

inventor An invention is a unique or novel device, method, composition, idea or process. An invention may be an improvement upon a machine, product, or process for increasing efficiency or lowering cost. It may also be an entirely new concept. If an ...

. He contributed 270 articles to the

Encyclopédie ''Encyclopédie, ou dictionnaire raisonné des sciences, des arts et des métiers'' (English: ''Encyclopedia, or a Systematic Dictionary of the Sciences, Arts, and Crafts''), better known as ''Encyclopédie'', was a general encyclopedia publis ...

in the subjects of

arithmetic Arithmetic () is an elementary part of mathematics that consists of the study of the properties of the traditional operations on numbers— addition, subtraction, multiplication, division, exponentiation, and extraction of roots. In the 19th ...

and

geometry Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is c ...

. In June 1747 he was elected a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural science, natural knowledge, incl ...

of London. He was the inventor of a primitive

diving suit A diving suit is a garment or device designed to protect a diver from the underwater environment. A diving suit may also incorporate a breathing gas supply (such as for a standard diving dress or atmospheric diving suit). but in most cases the te ...

in 1775, which he called a "scaphandre" from the Greek words ''skaphe'' (boat) and ''andros'' (man) in his book ''Traité de la construction théorique et pratique du scaphandre ou du bateau de l'homme'' (Treatise on the theoretical and practical construction of the "Scaphandre" or human boat). The invention of the Abbé de la Chapelle consisted of a suit made of

cork Cork or CORK may refer to: Materials * Cork (material), an impermeable buoyant plant product ** Cork (plug), a cylindrical or conical object used to seal a container ***Wine cork Places Ireland * Cork (city) ** Metropolitan Cork, also known as G ...

which allowed soldiers to float and swim in water. As the name and description suggest, it was more of a flotation suit than a

Publications

* ''Discours sur l’Étude des Mathématiques'', Paris, 1743. * ''Institutions de Géométrie, enrichies de notes critiques et philosophiques sur la nature et des développements de l’esprit humain; précédées d’un Discours sur l’Étude des Mathématiques'', 2 vol., Paris 1746, 1757. * ''Traité des sections coniques et autres courbes anciennes, appliquées et appliquables à la pratique des differens arts'', 1750. * ''L’Art de communiquer ses idées, enrichi de notes historiques et philosophiques'', London, 1763. * ''Le Ventriloque, ou l’Engastrimythe'', London & Paris, 1772 (sur Google Books). * ''Traité de la Construction théorique et pratique du Scaphandre ou du bateau de l’homme, approuvé par l’Académie des Sciences'' (Paris 1774) ; réédité sous le titre ''Traité de la construction théorique et pratique du scaphandre ou bateau de l’homme… par M. de La Chapelle. Nouvelle édition… Précédé du Projet de formation d’une légion nautique ou d’éclaireurs des côtes, destinée à opérer tels débarquemens qu’on avisera sans le secours de vaisseaux… par… La Reynie… ean-Baptiste-Marie-Louis de La Reynie de La Bruyère' (Paris an XIII – 1805)

Sources

*Frank Arthur Kafker, ''The encyclopedists as individuals: a biographical dictionary of the authors of the Encyclopédie'', Oxford, Studies on Voltaire and the eighteenth Century, 1988, p. 181-4, . {{DEFAULTSORT:Chapelle, Jean-Baptiste De La 1710 births 1792 deaths 18th-century French mathematicians Fellows of the Royal Society Contributors to the Encyclopédie (1751–1772) 18th-century French inventors