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Jacques Étienne Montgolfier

Template:Otheruses The brothers, Joseph Michel Montgolfier (26 August 1740 – 26 June 1810) and Jacques Étienne Montgolfier (6 January 1745 – 2 August 1799), invented the montgolfière, or hot air balloon. Their invention was the first aircraft to carry humans into the sky.

Early years

The brothers were born into a family of successful paper manufacturers in Annonay, south of Lyon, France. Their father, Pierre (1700-1793), established his eldest son Raymond (1730-1772) as his successor. As a result, the younger sons were initially sent away to school to learn other professions.

Joseph possessed a typical inventor's temperament -- a maverick and dreamer but impractical in terms of business and personal affairs. Clever and highly inventive by nature, he was rebellious towards his formal education -- twice running away from school. Nonetheless, his natural curiosity led him to a very successful self-education in the then emerging physical sciences. He eventually returned to the family homestead, but was only peripherally involved in the family paper-making business.

Étienne (as Jacques Étienne was more generally known) had a much more even and businesslike temperament than Joseph. He was initially sent to Paris to train as an architect. However, after the sudden and unexpected death of Raymond in 1772, he was recalled to Annonay to run the family business (no serious consideration was given to the elder Joseph in this role, given his uneven behaviour.) In the subsequent 10 years, Étienne applied his talent for technical innovation to the family business (papermaking was a high tech industry in the 18th century.) He succeeded in incorporating the latest innovations of the day into the family mills. His work led to recognition by the government of France as well as the awarding of a government grant to establish the Montgolfier factory as a model for other French papermakers.

Initial experiments

Of the two brothers, it was Joseph who first contemplated building flying machines.

There is no definitive account of when Joseph first started contemplating lighter-than-air flight. Some accounts put it as early as 1777 when Joseph observed laundry drying over a fire incidentally form pockets that billowed upwards.

Joseph made his first definitive experiments in November of 1782 while living in Avignon. He reported, some years later, that he was watching a fire one evening while contemplating one of the great military issues of the day -- an assault on the fortress of Gibraltar, which had proved impregnable by both sea and land. Joseph mused on the possibility of an air assault using troops lifted by the same force that was lifting the embers from the fire. He believed that contained within the smoke was a special gas, called 'Montgolfier Gas', with a special property he called 'levity'.

As a result of these musings, Joseph set about building a box-like chamber 1 m by 1 m by 1.3 m (3 ft by 3 ft by 4 ft) out of very thin wood and covering the sides and top with lightweight taffeta cloth. Under the bottom of the box he crumpled and lit some paper. The contraption quickly lifted off its stand and colided with the ceiling.

Joseph then recruited his brother to balloon building by writing the prophetic words: "Get in a supply of taffeta and of cordage, quickly, and you will see one of the most astonishing sights in the world." From that point forward, the brothers worked as a team.

Early in next month, December 1782, Joseph repeated his experiment out of doors in a garden near the family homestead with his entire family as witness. On this occasion, the box-like balloon lifted to some 20 meters (70 ft) in the air and remained aloft for a full minute.

The two brothers then set about building a contraption 3 times larger in scale (27 times larger in volume). The lifting force was so great that they lost control of their craft on its very first test flight on 14 December 1782. The device floated nearly 2 kilometres (about 1.2 mi). It was destroyed after landing by what Etienne later called the "indiscretion" of passersby.

Public demonstrations

Given these initial successes, the brothers decided to make a public demonstration of a balloon in order to establish their claim to its invention.

They constructed a globe-shaped balloon (there are no reports as to whether the balloon was plain or decorated) of sackcloth with three thin layers of paper inside. The envelope could contain nearly 790 m³ (28,000 cubic feet) of air and weighed 225 kg (500 lb). It was constructed of four pieces (the dome and three lateral bands), and held together by some 1,800 buttons. A reinforcing "fish net" of cord covered the outside of the envelope.

A model of the Montgolfier brothers balloon at the London Science Museum

On 4 June 1783 (many sources incorrectly fix the date as 5 June), they flew this craft as their first public demonstration at Annonay in front of a group of dignitaries from the Etats particulars. Its flight covered 2 km (1.2 mi), lasted 10 minutes, and had an estimated altitude of 1,600 - 2,000 m (5,200 - 6,600 ft).

Word of their success quickly reached Paris. Etienne went to the capital to make further demonstrations and to solidify the brothers' claim to the invention of flight. Etienne had studied in Paris and was much more at home with the dress and habits of the city. Joseph, given his unkempt appearance and shyness, remained with the family.

There was an intense competition between the brothers and Jacques Alexandre César Charles who had already made a public demonstration of a balloon using hydrogen as its lifting gas.

In collaboration with the successful wallpaper manufacturer, Jean Baptiste Réveillon, Etienne constructed a 37,500 cubic foot envelope of taffeta coated with varnish. The balloon was covered in bright colours and flourishes to distinguish it from the rather plain design of the Charles balloons. The bold design was no doubt the influence of Réveillon, the wallpaper maker.

There was some concern about the effects of flight into the upper atmosphere on living creatures. Some reports say King Louis XVI of France forbade human flight until the effects on animals had been determined. However, there is no written evidence of this edict. Rather it is most likely that the inventors themselves decided to send animals aloft first.

On 19 September 1783 the Aerostat Réveillon (as Etienne referred to it) was flown with the first living beings in a basket attached to the balloon: a sheep, a duck and a rooster. This demonstration was performed before a huge crowd at the royal palace in Versailles, before King Louis XVI of France and Queen Marie Antoinette.

The flight lasted approximately 8 minutes, covered 2 miles, and obtained an altitude of about 1500 feet. The flight would have been longer but the craft was unstable. It tipped wildly just after launch which allowed a considerable amount of hot air to spill from the mouth. The animals survived the trip unharmed.

One of the first people at the site of the landing was Pilâtre de Rozier who had already volunteered to be one of the first humans aloft when the time came. (Pierre Montgolfier, father of the inventive brothers, had given his permission for his sons to work on balloons rather than the family papermaking business only on the condition that neither of the brothers ever go aloft in a balloon themselves.)

Human flight

With the successful demonstration at Versailles, and again in collaboration with Réveillon, Etienne started construction of a 60,000 cubic foot balloon for the purpose of making flights with humans. (Etienne's excursion, albeit tethered was the cause of much paternal consternation as he had promised his father that he would not ride in a balloon himself.) The craft was once again decorated with flourishes and was 75 feet tall and 46 feet in diameter.

The balloon was tested in tethered flights later in 1783 on 15, 17 and 19 October. At different times, Etienne and Pilâtre de Rozier on board. On occasion, these tethered flights reached the limits of the 324 foot long retaining ropes.

On 21 November 1783, the first free flight by humans was made by Pilâtre de Rozier and the marquis d'Arlandes, who flew aloft for 25 minutes about 100 metres above Paris for a distance of nine kilometres. The flight began in the courtyard of the Château de la Muette in the western outskirts of Paris and landed between the windmills on the Butte-aux-Cailles. Enough fuel remained on board at the end of the flight to have allowed the balloon to fly four to five times as far. However, burning embers from the fire were scorching the balloon fabric and had to be daubed out with sponges. Thus the pilots decided to land as soon as they were over open countryside.

The ascensions made a sensation. Numerous engravings commemorated the events. Chairs were designed with balloon backs, and mantel clocks were produced in enamel and gilt-bronze replicas set with a dial in the balloon. Less affluent Frenchmen could buy crockery decorated with naive pictures of balloons.

Following years

Only one of the brothers (which one is unknown) ever flew in a balloon himself, but only once.

In 1766, the British scientist Henry Cavendish had discovered hydrogen gas, by adding sulphuric acid to iron, tin, or zinc shavings. The development of gas balloons proceeded almost in parallel with the work of the Montgolfiers. This work was led by Messr. Charles. Work on each type of balloon was spurred on by the knowledge that there was a competing group and alternative technology.

For a variety of reasons, including the fact that the French government chose to put a proponent of hydrogen in charge of balloon development, hot air balloons were superseded by hydrogen gas balloons.

Hydrogen balloons became the predominant technology for the next 180 years. They were used for all major ballooning accomplishments such as the crossing of the English Channel on 7 January 1785, by Jean-Pierre Blanchard and John Jeffries.

Revival of the hot air balloon

Balloons using heated air rather than lighter-than-air gasses did not return until the 1960s, when Ed Yost improved the safety of the classic Montgolfier design by using ripstop nylon for the envelope and propane gas as the burner fuel.

See also

Les Neuf Sœurs

External links

• "Lighter than air: the Montgolfier brothers"
• "Balloons and the Montgolfier brothers"