Jean Baptiste Marie Charles Meusnier de la Place (

Tours Tours ( , ) is one of the largest cities in the region of Centre-Val de Loire, France. It is the prefecture of the department of Indre-et-Loire. The commune of Tours had 136,463 inhabitants as of 2018 while the population of the whole metrop ...

, 19 June 1754 — le Pont de

Cassel Cassel may refer to: People * Cassel (surname) Places ;France * Cassel, Nord, a town and commune in northern France ** Battle of Cassel (1071) ** Battle of Cassel (1328) ** Battle of Cassel (1677) ;Germany * Cassel, Germany, a city in Hesse rena ...

, near Mainz, 13 June 1793) was a French mathematician,

engineer Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the lim ...

and Revolutionary 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.

Dirigible balloon

Meusnier is sometimes portrayed as the inventor of the dirigible, because of an uncompleted project he conceived in 1784, not long after the first

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

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 commune An ...

s, and presented to the French Academy of Sciences. 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 and the

Robert brothers Les Frères Robert were two French brothers. Anne-Jean Robert (1758–1820) and Nicolas-Louis Robert (1760–1820) 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.Biographical dictionary of the history of technology, Volume 39 By Lance Day, Ian McNeil. Charles, Jacques Alexandre Cesar
/ref> On 15 July 1784 the brothers flew for 45 minutes from Saint-Cloud to

Meudon Meudon () is a municipality in the southwestern suburbs of Paris, France. It is in the département of Hauts-de-Seine. It is located from the center of Paris. The city is known for many historic monuments and some extraordinary trees. One of t ...

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 or card. Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a sho ...

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 Beuvry () is a commune in the Pas-de-Calais department in the Hauts-de-France region in northern France. Geography A suburban town immediately southwest of Béthune, southwest of Lille, at the junction of the D945, D72 and N41 roads. Light ind ...

near

Béthune Béthune ( ; archaic and ''Bethwyn'' historically in English) is a city in northern France, sub-prefecture of the Pas-de-Calais department. Geography Béthune is located in the former province of Artois. It is situated south-east of Calais, ...

, passing over

Saint-Just-en-Chaussée Saint-Just-en-Chaussée ( pcd, Saint-Just-in-Cœuchie) is a commune in the Oise department in northern France. Saint-Just-en-Chaussée station has rail connections to Amiens, Creil and Paris. History Its name refers to Saint Justus of Beauvais ...

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, he was injured during the

siege of Mainz (1793) In the siege of Mainz (german: Belagerung von Mainz), from 14 April to 23 July 1793, a coalition of Prussia, Austria, and other German states led by the Holy Roman Empire besieged and captured Mainz from revolutionary French forces. The allie ...

and died of his wounds.Jean-Baptiste-Marie charles meusnier de la place (1754–1793): an historical note
/ref> For his military service, his is one of the

names inscribed under the Arc de Triomphe The following is a list of the 660 names inscribed under the Arc de Triomphe, in Paris. Most of them represent generals who served during the French First Republic (1792–1804) and the First French Empire (1804–1815). Underlined names signify tho ...

(as MEUNIER).

Notes

References