The Age of Wonder (24 page)

3
Balloonists in Heaven

1

Herschel’s international success was a great encouragement to Joseph Banks at this time. He was still privately suffering from the loss of his friend Solander, and was being harassed by internecine intellectual feuds at the Royal Society (particularly among the unworldly mathematicians). It was with no little relief that in August 1783 he began to receive secret reports in Soho Square of strange rumours from Paris about the possible existence of a French flying machine.

The dream of flight had haunted men-especially poets, satirical writers and impractical fantasists-since the myth of Icarus. European literature was full of unlikely bird machines, flapping chariots, flying horses and aerial galleons. None of them were remotely practicable. But this was something quite different: a giant ‘aerostat’ powered by ‘inflammable air’. What was more, it was being seriously investigated by the French Academy of Sciences, under the redoubtable Marquis de Condorcet.

Banks’s most reliable informant was the wily old American Ambassador to France, Benjamin Franklin, a corresponding member of the Royal Society, and now aged seventy-seven, a shrewd judge of both men and machines. After seven years at the Embassy in Paris, Franklin was still a francophile and an enthusiast, and had just delivered a sparkling report on the craze for mesmerism, or ‘Animal Magnetism’. He had noted that Anton Mesmer had earned 20,000 louis d’or ‘by this pretended new Art of Healing’.
¹

Franklin now wrote to Banks describing something even more fantastic: a series of aerial experiments involving very large paper bags. These bags had apparently been flown in the open air to a considerable height by a paper manufacturer near Lyons in June that year. The paper-maker, whose name was Joseph Montgolfier, was bringing his bags to Versailles to give a public demonstration before King Louis XVI. It was scheduled to be held in the large courtyard in front of the palace that September.

All this sounded fantastical enough. But then Franklin reported that a member of the Académie des Sciences, Dr Alexandre Charles, had stolen a march on Montgolfier by inflating a silk bag with the newly discovered ‘inflammable air’ and launching it in public from the Champs de Mars on 27 August. What was astonishing was the lifting power of this simple device. The silk bag or ‘balloon’, although it was only six feet in diameter, had quickly risen so high that it could no longer be seen. It had crossed the Seine and travelled fifteen miles outside Paris before it burst. This was a distance which a horseman could barely cover in a hour at the gallop.

Then Franklin reported that Montgolfier and his brother Étienne had successfully launched their own balloon from Versailles on 11 September. Unlike Charles’s gas balloon, it was powered by hot air, it was very big, and it was beautifully decorated with heraldic symbols. Moreover, its lifting power was spectacular. In a wicker cage attached to the neck of the bag it had carried a sheep, a duck and a cockerel (the French national symbol) right over the rooftops of Versailles, and had stayed aloft for seven minutes. All the animals had returned to earth alive and well.

It was clear what would happen next. Either the Montgolfiers or Charles would try to send a man up in a balloon. The prospect was amazing, and nothing else was talked about in France. Franklin thought that balloons might eventually ‘pave the way to some discoveries in Natural Philosophy of which at present we have no conception’. He instanced the examples of ‘magnetism and electricity, of which the first experiments were mere matters of amusement’.
²

Initially Banks wrote back sceptically. ‘I see an inclination in the more respectable part of the Royal Society to guard against the
Ballomania
until some experiment like to prove beneficial either to society or science is proposed.’ Nevertheless, he conceded by mid-September 1783 that with the Montgolfiers’ ‘Aerostatic Experiment’ at Versailles, the French had ‘opened a Road in the Air’, and this might mark a new ‘Epoch’. If further experiments proved successful, then ‘The immediate Effect it will have upon the Concerns of Mankind [will be] greater than anything since the invention of Shipping.’
³

Paradoxically enough, Banks’s first conception of balloon transportation was a thoroughly earthbound one. He saw the balloon as ‘a counterpoise to Absolute Gravity’: that is, as a flotation device to be attached to traditional forms of coach or cart, making them lighter and easier to move over the ground. So ‘a broad-wheeled wagon’ normally requiring eight horses to pull it might need only two horses with a Montgolfier attached. This aptly suggests how difficult it was, even for a trained scientific mind like Banks’s, to imagine the true possibilities of flight in these early days.
⁴

2

Banks was very conscious that the discovery of a lighter-than-air gas had actually been achieved by two English chemists, Henry Cavendish and Joseph Priestley. They had called it ‘inflammable air’ because of its lightness and explosive properties. Priestley’s
Experiments on Different Kinds of Air
had been translated in France in 1768. All the experiments had then been repeated and refined by their rival, the great French chemist Antoine Lavoisier, in Paris. He had measured the buoyancy of this ‘
gaz
’ (a word not yet coined in English) more accurately, and renamed it ‘hydrogen’. But no one had manufactured it on a large scale, or realised its dramatic practical applications.

The Montgolfier brothers were commercial paper manufacturers from Annonay, near Lyons, in the Ardèche. They were an effective business team. Joseph was the shrewd entrepreneur, and Étienne was the madcap inventor. They were interested in chemistry for commercial reasons. They had followed Priestley’s and Lavoisier’s work, and had speculated about putting lighter-than-air gas into paper containers. As early as 1782, Joseph had humorously suggested the theoretical possibility of flying an entire French army into Gibraltar, and seizing it from the English. The troops would fly suspended beneath hundreds of huge paper bags.
⁵

Lavoisier’s ‘hydrogen’ was produced by passing sulphuric acid over iron filings. It was one-thirteenth of the weight of common air, and consequently could produce a powerful lift if sufficiently concentrated in a light container (Cavendish had used soap bubbles). But it was slow and dangerous to produce, potentially explosive, and easily escaped from containers made of silk or animal bladders. Hot air, on the other hand, was easily produced by any kind of controlled fire, and could be temporarily contained in inflated silk or paper. It produced a short-term lift, as heat agitates the air molecules, making them move apart and become more buoyant than the surrounding cooler, denser air (and at best about half its weight). This lift was however less powerful than that of hydrogen, was easily dissipated, and consequently required much bigger balloons to sustain the same power of ascent, or carry the same payload.

Joseph Montgolfier later said he had tried Lavoisier’s ‘
gaz
’ unsuccessfully, but discovered the principle of hot air by watching his wife’s chemise inflating when she hung it over the hearth to dry.
⁶
He made several small experimental ‘aerostats’, finally adopting a pear-shaped balloon, with a wide neck that could be lowered over a fire. The Montgolfiers described it memorably as ‘putting a cloud in a paper bag’.

On 5 June 1783, they successfully launched their first large paper balloon in open country outside Annonay. It was probably intended as a piece of advertising for their paper business, and it was a dazzling sight. When inflated, their balloon stood thirty foot high, 110 feet in circumference, and took eight men to hold it down. It was crudely constructed of painted silk sections backed with coarse paper and simply buttoned together. In fact it contained no hydrogen gas at all, but simply 22,000 cubic feet of hot air collected from braziers burning straw and damp wool. French hot air proved to have enormous lifting power. When released it rose gracefully to an estimated 6,000 feet, barely visible, and remained aloft for ten minutes.
⁷

Perhaps most significant of all, it drew an enormous crowd of onlookers. This ability of the balloon to attract attention and pull large numbers of people has always remained part of its mystique, and an important part of its history. Montgolfier had discovered a scientific principle quite as interesting as that of aerial buoyancy. With ballooning, science had found a powerful new formula: chemistry plus showmanship equalled crowds plus
wonder
plus money. Reports of the flight travelled throughout France, and the Montgolfiers were soon invited to give official demonstrations, first at Versailles and then in Paris. The Marquis de Condorcet, the head of the Académie des Sciences, appointed a committee to investigate the invention and consider sponsoring its development. It assembled France’s leading men of science, including Lavoisier and Claude Berthollet.
⁸

Now there was the feeling of urgency, even of a race. People began contacting the Montgolfiers, applying to the Académie, or publicly volunteering to be ‘the first aerial traveller in the world’. One was a young inventor from Normandy, Jean-Pierre Blanchard, who had already been experimenting with a number of winged flying machines, most notably a flying tricycle. He announced boldly in the
Journal de Paris:
‘Within a very few days I shall be ready to demonstrate my own aerostatic machine, which will climb and dive on command, and fly in a straight line at a constant altitude. I shall be at the controls myself, and have sufficient confidence in my design to have no fear of repeating the fate of Icarus.’
⁹

Another, better-connected but no less enthusiastic candidate, was a young Parisian doctor, Jean-François Pilâtre de Rozier. Pilâtre was a professor of natural philosophy who ran a private science museum and college in the rue Saint-Honoré. He was twenty-nine years old. He had invented a gasmask, a hydrogen blowtorch, and a new theory of thunder-all of which seemed equally relevant to ballooning. A small, neat, energetic figure of infectious charm, he was a considerable ladies’ man. He had good contacts within the Académie des Sciences and the Ministry of Finance, and some said particularly with ‘Madame’ (the Comtesse de Provence, Louis XVI’s sister-in-law). He would soon be pursued by a number of intellectual aristocrats, such as Madame de Saint-Hilaire. But with his charm went extraordinary
sangfroid
-and of course a head for heights. Pilâtre proved himself fearless and precise during the most alarming experiments, and soon made himself indispensable to the Montgolfiers. He had, in effect, invented the new profession of test pilot. He had the right stuff.
¹⁰

On 21 November 1783 the first manned Montgolfier balloon was launched from the hill of La Muette. This was a commanding site just above the river Seine at Passy, opposite the Champs de Mars (where the Eiffel Tower now stands). The hot-air balloon was enormous, a monster: seventy feet high, and gloriously decorated in blue, with golden mythological figures. It was powered by a six-foot open brazier burning straw. Its chosen ‘aeronauts’-another new French term-were Pilâtre de Rozier and an elegant infantry officer, the Marquis d’Arlandes, a major in the Garde Royale. D’Arlandes was selected for his court connections, his enthusiasm and his wealth; and also simply because the Montgolfiers needed a ‘counterweight’. Since Pilâtre was to be carried aloft in a circular gallery slung around the open neck of the balloon (and not in a basket), his weight had to be constantly balanced by a second aeronaut on the opposite side. D’Arlandes became therefore, by default, the first co-pilot as well as the first aerial stoker.

D’Arlandes subsequently published a laconic account of their historic voyage, which took them low over Paris for about twenty-seven minutes. The Montgolfier (as the balloon was now known) initially rose to some 900 feet, drifted across the Seine, and then began a series of slow swoops across the rooftops of Saint-Germain, narrowly missing the towers of Saint-Sulpice, rising again over the wooded parkland of the Luxembourg, and finally sinking rapidly onto the Buttes aux Cailles (near the present Place d’Italie in the 13th arrondissement), narrowly missing two windmills.

Because of the circular structure of the gallery, with the neck of the balloon (and the brazier) in the centre, the aeronauts could barely see each other during the flight. This produced a kind of black comedy which was to become familiar in later ascents. Pilâtre spent much of his time calling to the invisible d’Arlandes to stop admiring the view of Paris and stoke the brazier. ‘Let’s work, let’s work!-If you keep gaping at the Seine, we’ll be swimming in it soon.’

In fact d’Arlandes seems to have been increasingly (and not unnaturally) overcome by nerves. First he thought the balloon was on fire, then that the canopy was separating from the gallery, and finally that one after another the balloon cords were breaking. He constantly shouted back at the unseen Pilâtre, ‘We must land now! We must land
now!
’ When the whole balloon shook with a sudden gust of wind above Les Invalides, d’Arlandes screamed at Pilâtre: ‘What are you doing!
Stop dancing!
’

Characteristically, Pilâtre ignored these protests, and calmly went on telling d’Arlandes to work at feeding the brazier. He himself took off his bright green topcoat (put on for the crowd), rolled up his sleeves, and went on throwing on straw till his wooden fork broke. Once, when d’Arlandes was desperately shouting at him, ‘We must go down! We must go down!’, Pilâtre called back soothingly: ‘Look d’Arlandes.
Here we are above Paris.
There’s no possible danger for you.
Are you taking this all in?
’ Many witnesses later said that they could hear the two men shouting excitedly to each other as they passed overhead. They assumed they were describing the glories of flight.