Automobiles and airplanes are more closely related than it would appear at first. As early as 1888, Gottlieb Daimler had supplied the engine for an airship owned by Leipzig-based bookseller Friedrich Hermann Wölfert. Both Daimler-Motoren-Gesellschaft (DMG) and Benz & Cie. started developing engines specifically for aircraft even before World War I. During the course of the war, it became apparent that the engines did not supply sufficient power at high altitude due to the low air density. DMG solved this problem by developing the supercharger, which compressed the intake air, thus compensating for power loss.