A hot-air balloon, he thought, was rather dangerous because of its open flame.
Hydrogen, although inflammable, was completely enclosed in the balloon making it safer.
The first manned hydrogen balloon flight by Jacques Charles with Nicolas-Louis Robert, December 1, 1783.
Jacques Charles decided to build one.
Charles designed the balloon and asked the Robert brothers to construct a lightweight but airtight gas bag.
The sheets of silk were then stitched together to make the main envelope.
The resulting hydrogen was fed to the balloon through a connecting hose from the barrel.
Inflation of the first hydrogen balloon.
Hydrogen production by chemical reaction was a slow process and so the filling took several days.
But the apparatus did not function properly, and they reverted to using the barrel.
To keep the crowd interested, Charles issued daily progress bulletins on the inflation.
Finally, after innumerable technical difficulties and delays, the balloon was ready.
The balloon was released when a storm had began to gather.
But the bad weather did not spoil the enthusiasm of the gathered crowd.
Villagers attacking the hydrogen balloon because they weren’t used to things flying.
Among the crowd of onlookers who saw the balloon fly was Benjamin Franklin.
On July 15, 1784, the Robert brothers flew in this craft for 45 minutes.
The Robert brothers flew again, this time with M. Collin-Hullin, on September 19, 1784.
Charles also described how gases tend to expand when heateda law that now bears his name.
