Lighter than air
The unrestricted market leader in the time of Lilienthal: Aeronautics. Gas balloons had already been tested and were common, also there were projects for steerable airships.
Airship project of the French naval engineer Dupuy de Lome (1872) - developed during the Franco-German-War
Ballonaufstieg Goddard 1866
Airship Design Petin 1850
Figures from the Histoire de L'Aéronautique, 1932
Voice actor: K. Albrecht / H. Gülland