French balloon pioneer Jean Marie Joseph Coutelle (1748-1835) was appointed Captain of aerostiers, in command of the French army's first balloon unit. Coutelle was the first military balloon observer, using balloons for aerial observations of enemy movements. The tethered balloon had to be very strong to withstand gusts of wind. Observers could signal to the ground with flags, or send mesages which were slid down the cables. Illustration from 'Histoire des ballons et des aeronautes celebres: 1783-1800' (History of balloons and famous aeronauts), by Gaston Tisandier (1843-1899), published in 1887.
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