montgolfière

The brothers, Joseph Michel Montgolfier (26 August 1740 – 26 June 1810) and Jacques-Étienne Montgolfier (6 January 1745 – 2 August 1799) were the inventors of the montgolfière, globe airostatique or European hot air balloon. The brothers succeeded in launching the first manned ascent to carry a young physician and an audacious army officer into the sky.
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n. observation balloon, ballon used for recording facts (mainly for research about weather conditions)