Not just a lot of hot air
UK: PARIS salons were well known for flatulence in conversation. After each manned flight of giant balloons from the gardens of Versailles during the late 18th and 19th centuries, young men who wished to sound like scientists would earnestly debate whether hydrogen gas or hot air allowed the better flight.
For anyone ignorant of convection, one of those in favour of hot air might have lifted the lid on a …