Artificial Clouds and Inflammable Air: The Science and Spectacle of the First Balloon Flights, 1783
Colored etching by an unknown artist depicting the first manned hydrogen balloon ascending from the Tuileries Gardens.
Library of Congress, LC-DIG-PPMSCA-02439. |
Joseph and Étienne Montgolfier were two of sixteen siblings from a prosperous papermaking family in southern France. Jacques-Alexandre-César Charles was an urbane Parisian man of science, well-known for his public physics lectures. In the 1780s the Montgolfier brothers and Charles engaged in a spectacular race to levitate into the sky using gas-powered balloons. Their “artificial clouds,” as one writer described the flying globes, would enthrall the French capital and set off a craze for all things balloon.
The story of the first balloons starts with a classic “Eureka!” moment. As Joseph Montgolfier (1740–1810) later related, he was sitting by a fireplace one day in 1782, thinking about the fortress-like island of Gibraltar, then held by Spain. Watching the sparks and smoke go up the flue, he pondered putting hot air to military use. Steam power had been used since the beginning of the century, and even at this early stage of the Industrial Revolution improved steam engines were working in growing numbers of mines, mills, and factories. What if heated, expanding air could lift some sort of conveyance to carry soldiers for an aerial invasion, just as steam drove pumps and pistons?
To try his notion Joseph constructed a light, angular wooden framework, covered it with taffeta, and burned some paper at its lower opening. It quickly rose up to the ceiling, thrilling the dreamy inventor. Soon he and his practical brother Étienne (who was in charge of calculating size, shape, and lifting power) were creating and testing ever-larger balloons made of pieces of paper-backed cloth fastened together by cords passed through hundreds of buttonholes. After a successful public demonstration near their home in southern France, witnessed by the local assembly, published accounts of the marvel soon reached Paris.
The news excited many in the capital, including Jacques-Alexandre-César Charles (1746–1843). Well-educated and an accomplished musician, Charles was familiar with the actions of gases and owned one of the finest private collections of scientific instruments in Europe. Using these instruments in the popular science courses he taught for paying customers, Charles worked constantly to improve his experiments, believing that visual, concrete demonstrations could explain physical laws. He was thus ideally suited to compete with the Montgolfiers in developing these new flying machines, though initially he aimed only to replicate their endeavors as a contribution to scientific knowledge.
Charles thought at first that the Montgolfiers had used hydrogen gas to lift their balloon, as no other lighter-than-air gas was known at the time, and he did not yet know that ordinary atmospheric air could expand enough when heated to lift such a structure. So he recruited two instrument makers, brothers Anne-Jean and Marie-Noël Robert, to help him generate an immense, unprecedented volume of hydrogen gas. To help pay for this expensive undertaking, naturalist and geologist Barthélemy Faujas de Saint-Fond opened a public subscription, selling tickets for a demonstration with time and place to be announced. Despite such vagueness, the elite of Paris quickly signed up, eager to be among the first to see this daring experiment.
Making Gases Fly
For balloons to truly take off, scientists needed to understand how gases worked. Though still in its infancy, the science of gases was advancing quickly. Inspired by Enlightenment beliefs in reason and progress, 18th-century natural philosophers were seeking to unlock nature’s mysteries, including the properties of air—invisible and untouchable, yet ubiquitous and necessary for life. Realizing that atmospheric air was not a single substance, scientists worked to separate air into its component gases, analyzing and observing the properties of each. Englishman Henry Cavendish had isolated hydrogen in 1766, naming it “inflammable air” for its readiness to burn. In the 1770s Joseph Priestley in England, Carl Wilhelm Scheele in Germany, and Antoine-Laurent Lavoisier in France all contributed to the discovery of oxygen. Priestley called his gas “dephlogisticated air” because it apparently lacked “phlogiston,” the universal component of fire then thought to reside in all combustible substances. In June 1783 Lavoisier proved that water was not an element but rather a combination of hydrogen and oxygen. He was soon able to overturn the dominant phlogiston theory, laying the groundwork for modern chemical terminology and methods. Charles would later make an important contribution to this effort in 1787, when he formulated the law of gases that now bears his name. Eventually elaborated by Joseph-Louis Gay-Lussac, Charles’s law states that under constant pressure the volume of a fixed weight of gas is directly proportional to its absolute temperature—a principle that would prove essential to ballooning.
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