Jean Baptiste Marie Charles Meusnier de la Place (

Tours Tours ( ; ) is the largest city in the region of Centre-Val de Loire, France. It is the Prefectures in France, prefecture of the Departments of France, department of Indre-et-Loire. The Communes of France, commune of Tours had 136,463 inhabita ...

, 19 June 1754 — le Pont de Cassel, near

Mainz Mainz (; #Names and etymology, see below) is the capital and largest city of the German state of Rhineland-Palatinate, and with around 223,000 inhabitants, it is List of cities in Germany by population, Germany's 35th-largest city. It lies in ...

, 13 June 1793) was a French

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, mathematical structure, structure, space, Mathematica ...

engineer Engineers, as practitioners of engineering, are professionals who Invention, invent, design, build, maintain and test machines, complex systems, structures, gadgets and materials. They aim to fulfill functional objectives and requirements while ...

and

Revolutionary A revolutionary is a person who either participates in, or advocates for, a revolution. The term ''revolutionary'' can also be used as an adjective to describe something producing a major and sudden impact on society. Definition The term—bot ...

general. He is best known for Meusnier's theorem on the curvature of surfaces, which he formulated while he was at the École Royale du Génie (Royal School of Engineering). He also discovered the helicoid. He worked with

Lavoisier Antoine-Laurent de Lavoisier ( ; ; 26 August 17438 May 1794),
CNRS (

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

Dirigible balloon

Meusnier is sometimes portrayed as the inventor of the

dirigible An airship, dirigible balloon or dirigible is a type of aerostat ( lighter-than-air) aircraft that can navigate through the air flying under its own power. Aerostats use buoyancy from a lifting gas that is less dense than the surrounding ...

, because of an uncompleted project he conceived in 1784, not long after the first

balloon A balloon is a flexible membrane bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, or air. For special purposes, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), ...

flights of the

Montgolfier The Montgolfier brothers – Joseph-Michel Montgolfier (; 26 August 1740 – 26 June 1810) and Jacques-Étienne Montgolfier (; 6 January 1745 – 2 August 1799) – were aviation pioneers, balloonists and paper manufacturers from the Communes o ...

s, and presented to the

French Academy of Sciences The French Academy of Sciences (, ) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefron ...

. This concerned an elliptical balloon (''ballonet'') 84 metres long, with a capacity of 1,700 cubic metres, powered by three propellers driven by 80 men. The basket, in the form of a boat, was suspended from the canopy on a system of three ropes.

Jacques Charles and ''Les Frères Robert''

After their successful hydrogen balloon flights in 1783, professor

Jacques Charles Jacques Alexandre César Charles (12 November 1746 – 7 April 1823) was a French people, French inventor, scientist, mathematician, and balloonist. Charles wrote almost nothing about mathematics, and most of what has been credited to him was due ...

and the

Robert brothers Les Frères Robert were two French brothers. Anne-Jean Robert (1758–1820) and Nicolas-Louis Robert (1760–1828) were the engineers who built the world's first hydrogen balloon for professor Jacques Charles, which flew from central Paris on ...

built an elongated, steerable craft that followed Jean Baptiste Meusnier's proposals. Their design incorporated Meusnier's internal ''ballonnet'' (air cell), a rudder, and a method of propulsion. On 15 July 1784 the brothers flew for 45 minutes from

Saint-Cloud Saint-Cloud () is a French commune in the western suburbs of Paris, France, from the centre of Paris. Like other communes of Hauts-de-Seine such as Marnes-la-Coquette, Neuilly-sur-Seine and Vaucresson, Saint-Cloud is one of France's wealthie ...

Meudon Meudon () is a French Communes of France, commune located in the Hauts-de-Seine Departments of France, department in the Île-de-France Regions of France, region, on the left bank of the Seine. It is located from the Kilometre Zero, center of P ...

with M. Collin-Hullin and Louis Philippe II, the Duke of Chartres in their elongated balloon. Rather than 80 men it was fitted with oars for propulsion and direction, but these proved useless. The absence of a gas release valve also meant that the duke had to slash the

envelope An envelope is a common packaging item, usually made of thin, flat material. It is designed to contain a flat object, such as a letter (message), letter or Greeting card, card. Traditional envelopes are made from sheets of paper cut to one o ...

to prevent it rupturing when they reached an altitude of about 4,500 metres (15,000 ft).Federal Aviation Administration - F.A.Aviation News, October 2001, Balloon Competitions and Events Around the Globe, Page 15
/ref>
/ref> On 19 September 1784 the brothers and M. Collin-Hullin flew for 6 hours 40 minutes, covering from Paris to Beuvry near

Béthune Béthune ( ; archaic and ''Bethwyn'' historically in English) is a town in northern France, Subprefectures in France, sub-prefecture of the Pas-de-Calais Departments of France, department. Geography Béthune is located in the Provinces of Fran ...

, passing over Saint-Just-en-Chaussée and the region of Clermont de l’Oise.Histoire Beuvry, Balloon revolution
This was the first flight over 100 km.

Giffard's dirigible

In 1852, sixty six years after Charles and the Robert brothers 'oar powered' dirigible, Henri Giffard's design for the first successful powered airship was inspired by Meusnier's ideas.

Meusnier's military career

During his military career he was put in charge of coastal defences in 1791. Fighting the Prussians on the

Rhine The Rhine ( ) is one of the List of rivers of Europe, major rivers in Europe. The river begins in the Swiss canton of Graubünden in the southeastern Swiss Alps. It forms part of the Swiss-Liechtenstein border, then part of the Austria–Swit ...

, he was injured during the siege of Mainz (1793) and died of his wounds. For his military service, his is one of the names inscribed under the Arc de Triomphe (as MEUNIER). The

UK Antarctic Place-Names Committee The UK Antarctic Place-Names Committee (or UK-APC) is a United Kingdom government committee, part of the Foreign and Commonwealth Office, responsible for recommending names of geographical locations within the British Antarctic Territory (BAT) an ...

named Meusnier Point after his legacy.

Notes

References

Jules Michelet Jules Michelet (; 21 August 1798 – 9 February 1874) was a French historian and writer. He is best known for his multivolume work ''Histoire de France'' (History of France). Michelet was influenced by Giambattista Vico; he admired Vico's emphas ...