Outside the laboratories of the rich, 18th-century science was developing a taste for the spectacular, powered by this new interest in gases.
Each year, the small French town of Annonay gathers together to recreate the time when an ancient dream of taking to the skies became a possibility.
Leading the celebrations are descendants of a family of famous paper makers — the Montgolfiers.
They were to launch the first hot-air balloon.
They had the idea of trapping hot air within a huge paper bag.
And it was this that went on to become the hot-air balloon.
At first, they thought it was the smoke that made it rise because the smoke rose.
But they soon realized it was the hot air that did it.
On the 4 June 1783, here in Annonay, the first balloon, made entirely out of paper, soared over a mile into the heavens.
Soon, balloon mania gripped France and a prize was offered for the first balloon to carry a man into the sky.
