“My god, look. It looks like there's a body! He’s moving, he’s alive! » Bending over the bloodied man lying in the bushes, the couple who were walking on the Champs-Élysées on December 3, 1804, heard him stammering. “There you go, if people had listened to me, this wouldn’t have happened…” said the dying man. Terrified, the two bourgeois who were taking a break in this corner of the forest near Paris, the day after the Emperor's coronation, fled to notify the police. When the constabulary arrived, the man was dead, his chest pierced by eleven stab wounds. He no longer has his watch. “Crime of prowlers, case closed,” sighs Pandora. It was the only funeral oration to which Philippe Lebon, the inventor of city lighting gas, was entitled when he was assassinated at the age of thirty-five.
The inventor was born on May 29, 1767, in Brachay, a small village in Haute-Marne, near Joinville. He revealed very early a precocious curiosity which prompted his father, a former officer of the veterans of the King's household, after brilliant studies in Châlons-sur-Marne, to enroll him in 1787 at the new school of Ponts et Chaussées, created twenty years ago. years earlier. His teachers quickly discovered his talents and, after two regulatory years, offered to keep him as a researcher and mathematics teacher. Philippe Lebon wishes to perfect “fire machines” and accepts. His every moment is devoted to experimentation.
In 1790, during a stay in his native village, he filled old bottles with sawdust and heated them. To avoid burning himself while holding them, he completely covers them with wet rags. The smoke, previously black and thick, then comes out very clear. Using a brand, he ignites this smoke which illuminates the room. “It burns better than wax or oil!” » Lebon has just built the first gas burner.
A revolutionary invention
Immediately realizing his interest in his find, he decided to repeat this experiment on a larger scale, using a brick stove. He fills it with wood and closes it hermetically, leaving only a thin pipe leading to a tank filled with water, the end of which widens to form a condenser container. As with the first experiment, the smoke is purified by passing through the water tank and the gas that comes out of the condenser can not only light but heat! Enthusiastic, Lebon declared to the peasants of the village who had rushed, fearing a fire: “My invention will heat you and light you even in the streets. »
In the meantime, we must live. The holidays over, Philippe Lebon returned to Paris and was soon appointed engineer of Bridges and Roads in Angoulême. He intends to finish developing his invention, considering that the carbonization of wood is a waste of energy and that the gases produced during this combustion will finally be used for several uses. Firstly for lighting, but at the same time we recover the tar and acids formed during the operation. Unfortunately, his superior, who has charged him with taking care of the navigation service in the Charente department, does not want his new subordinate to allow himself to divert part of his time to busying himself with "chimerical" projects.
Philippe Lebon, unimpressed by the remonstrances of his department head, continued his research with aplomb and, when he considered them to be successful, summoned to attend his demonstration, no less than the director of the Ponts et Chaussée school, engineer Prony himself. He notes: “From a kilogram of wood, I managed to release, through simple heat, the purest flammable gas in such abundance that it was enough to light up for two hours with as much luminosity as four or five candles. » His superior, exasperated with this deputy who neglects the service to develop “alleged inventions foreign to the Bridges and Roads service”, request his dismissal.
But Prony becomes enthusiastic and decides not to let such talent fester in the provinces. He announces that he will bring the young prodigy back to Paris to continue his experiments. His neighbors at 12 rue Saint-Louis-en-l'Isle quickly protested to the Department of Bridges and Roads, worried and unhappy with the smelly fumes that invaded their building. All come from the apartment of this young engineer who is working hard to build a gas machine at home. But their protests remain unheard. Prony doesn't care and encourages his protégé to continue his research at home.
The first gas lamp
On 6 Vendémiaire Year VII (September 28, 1799), Lebon filed the patent for his thermolamp, a device that distilled wood and produced a gas which, passing through a nozzle, produced lighting. A single stove can heat an entire building, making all chimneys unnecessary. In addition, it also illuminates the entire building. “No soot or ashes dirtying the interiors. Thanks to this complacent flame, we will be able to cook food, wash and dry laundry, heat baths, and produce a considerable change in our uses,” specifies the text of the patent (1).
In 1799, he presented a report to the National Institute on his work aimed at providing gas through carbonization which would also be used for heating and lighting. Continuing to perfect his invention, in 1801, Lebon published the summary of his research in a memoir: Thermolamps or stoves which heat, light with economy and offer with several precious products a driving force applicable to all types of machines.
Public lighting
To convince the skeptics, Lebon decides to make a full-scale demonstration. He rented the Colbert Hotel, boulevard Saint-Germain, near Rue de Bourgogne and installed thermolamp lighting there to produce the “magic of light”. On October 12, 1801, the presentation to the public took place. All of Paris runs there. The hotel and the gardens, lit by gas extracted from the wood, shine with light. The curious crowd jostles. Among the visitors, were many chemists, Fourcroy, Guyton, Chaptal, and various scientists, both French and foreign. Everyone is ecstatic, and Lebon is delighted. But the awakening is hard: his demonstration ruined him, no order having followed.
Chaptal, then Minister of the Interior, asked him for a variation of his invention to produce tar. The fleet needed it, the British blockade prohibiting France from importing this essential material for caulking ships, considered by its ministry much more interesting and urgent than lighting gas. Lebon then goes up near Le Havre, in the Rouvray forest, to a tar factory. He is required to produce five quintals of tar per day and lives on-site in a modest lumberjack cabin, his wife and son eking out a living in Le Havre, barely better housed than him. Being thirty-five years old, the inventor wants to offer better living conditions to his family.
He returned to Paris on December 2, 1804, invited to the coronation of Napoleon. What better opportunity to ask the Department of Bridges and Roads about his return to Île-de-France? He is considering moving to Marly-le-Roi to organize a pyroligneous acid factory. And that's the tragedy, the walkers discovering him mortally struck in the no-man's land of ill-repute that were then the wastelands of the Champs-Élysées.
His family is so destitute that without the Ponts et Chaussées administration which covers the burial costs, his body would have been thrown directly into the mass grave. He was buried in Père-Lachaise in a temporary concession for five years before his remains were emptied into a common grave. His name would have remained forever unknown without the tenacity of his wife.
The War of the Lamps
Françoise-Thérèse de Brambilla, who passionately supports her husband's research, does not want her work to disappear at the same time as her husband's body. The young widow raises her child alone, without resources. She must abandon the tar manufacturing business in the Rouvray forest, driven out by her husband's partner. She believes she can obtain a pension in Paris and discovers the twists and turns of the administration. Without regard for her situation, the bureaucracy, far from awarding her the slightest pension, makes "the Lebon woman born in Brambilla responsible for her husband's debts" and demands the reimbursement corresponding to the concession, i.e. a sum of eight thousand francs!
Without letting herself be discouraged, the young woman will work to have her husband's genius recognized. Over the next eight years, she deployed fantastic energy to publicize Lebon's work. She works, borrows, and knocks on every door without letting herself be discouraged by rebuffs. Having managed to raise the necessary sum, she worked to have her husband's patent recognized by resuming public demonstrations. On January 22, 1811, at 11 rue de Bercy, in the Faubourg Saint-Antoine, she had the building illuminated using thermoclines, allowing Parisians to discover Lebon's work. The apartments, courtyards, and gardens are illuminated with jets of light.
If the orders are not forthcoming, the press articles and scientific communications finally pay tribute to the French engineer. While Lebon was ignored before 1811, people began to carefully consider his “system”. Five years later, his invention spread in England, in particular through the engineer Murdock, thirteen years older than Lebon and who would survive him by thirty-five years. He attended his lighting experiment in 1801 at the Colbert Hotel and returning to Scotland resumed the process. In 1802, to celebrate the peace of Amiens, he managed to light the exterior facades of Watt in Soho. In 1807 he installed his first lamps in London to light Pall Mall.
Curiously, thanks to him, it will be from England that the gas lighting system will conquer France. The gas extracted from coal lights up stores and streets across the Channel. This transformation took place through financiers and investors like the Austrian J.A. Wintzler who, naturalized under the name of Albert Windsor, popularized Murdock's invention.
At the fall of Napoleon in 1815, emigrants – including King Louis XVIII who appreciated gas lighting in London for both the exterior and interior of houses – imposed on Paris what was, for them, an English invention. But in Liège, a Belgian engineer, Ryss-Poncelet, joined forces with Madame Lebon to exploit her husband's patents. The first lamps are installed in the Passage Montesquieu in Paris. “The public came in crowds to enjoy this dazzling lighting. »The war of the lamps begins. Vehement protests from the manufacturers of candles, candles, and oil lamps, producers of tallow, resin, and alcohol who are unleashed! “Are we going to commit the criminal madness of ruining the oilseed crops that produce lamp oil? Be aware that the gas causes terrible explosions. The dazzling light of the gas burns the eyelids and produces odious miasmas. »
A public interest investigation was ordered and an expert appointed, the chemist from Arcet. This concludes that thermolamps should be banned. In vain. The candle makers didn't win, however. In December 1815, Windsor had installations similar to those he had made in England installed in the panorama passage. Experts cannot prevent anything in the face of public enthusiasm. Two years later, this lighting system is essential. So much so that in 1830, upon his death, Windsor could rightly proclaim himself the “founder of gas lighting of cities”. But the “inventor” remains Lebon. And the Auer beak, or “incandescent beak” directly from his work, will light up all the Parisian streets in 1890, earning Paris the nickname “the city of lights”.