All for a shirt
The Montgolfier brothers had the idea of using hot air to raise a balloon. It is said that Jacques-Etienne discovered the possibilities of this technology when observing how his wife’s shirt inflated while drying on a stove. Hot air was easy to obtain and could be stored temporarily inside a paper or silk receptacle.
Globe in sight!
The Montgolfiers made a public demonstration of their invention on June 4, 1783, on the outskirts of Annonay. They designed a linen-lined globe of paper, which they filled with more than six hundred cubic meters of hot air, by burning straw and wet wool in braziers. It took eight men to hold the contraption, 11 meters in diameter. When they released it, it rose very quickly up to 1,800 meters. During the almost ten minutes he stayed in the sky, he moved about two kilometers.
The geologist Barthélmy Faujas de Saint-Fond wanted to build a hot air balloon in Paris. For this, he entrusted the project to the physicist Jacques Alexandre-César Charles, but he did not know what gas the Montgolfiers had used to elevate his invention. So he chose to fill his balloon with “flammable air,” a much lighter gas than the common one. Discovered by Henry Cavendish in 1766, it was none other than hydrogen, as it has been known since Antoine Lavoisier coined the term at the end of the 18th century.
A demonic monster
The hydrogen balloon of Charles and the Robert brothers, 18 m in diameter, rose nine hundred meters and moved almost twenty-five kilometers to rush near Gonesse. Partially deflated, that unidentified object terrorized the neighbors. Many believed that it was a foul-smelling and demonic creature fallen from heaven. People armed themselves with knives, pitchforks and stones and attacked the contraption until it collapsed with a groan. After this incident, the government issued a note assuring that the balloons were totally harmless.
The first aeronauts
King Louis XVI was a fan of science and technical advances, so he demanded a demonstration in Versailles. It was scheduled for September 19, 1783. Jacques Montgolfier worked hand in hand with his friend Jean-Baptiste Réveillon, a paper manufacturer, in the design of a varnished taffeta balloon. In this model, the balloon had a wicker basket attached. Montgolfier and Réveillon had determined to deposit in it a sheep, a duck and a rooster (the latter, the national symbol). These animals were going to be the first aeronauts. After three hours of inflation, the balloon rose with its load. After about ten minutes of flight and three kilometers of travel, the montgolfière landed with its crew safe.
Question of guts
He only had to risk flying in a balloon. An ambitious and charismatic physicist, Jean-François Pilâtre de Rozier, proved to have the nerve to do so. On October 19, together with the Marquis François Laurent d’Arlandes, he ascended to one hundred meters. Shortly after they performed the feat again, this time in front of Louis XVI. After almost half an hour of flight and about ten kilometers of journey, at a maximum height of nearly one thousand meters, they landed at Butte-aux-Cailles (now a Paris neighborhood). The first flight manned by humans was a success.
A better gas
Hydrogen was imposed to drive successive aerostats, but its associated danger (it was not called “flammable air” in vain) motivated its replacement by helium in the mid-nineteenth century. This inert gas, the second chemical element of the lighter periodic table, is much safer, due to its low flammability. All airships use it nowadays.
As we know them today
The American Paul Edward Yost introduced a series of improvements in the balloons at the end of the 1950s. This enthusiast of the aerostats replaced the old brazier with a propane gas cylinder, which allows reheating the air on demand and thus carry out more flights durable It also introduced synthetic fabrics, capable of reducing gas loss, and gave the traditional spherical globe a new teardrop appearance.