ng balloonets ofdirigible balloons, by which air may be distributedto different balloonets. U. S. Patent 959,392. May 24, 1910. Her-mann Ruthenberg. For a propeller; constructed by stretching clothand like over wire frame work. U. S. Patent 960,539. June 7th, 1910. Rob-ert E. Green. In this patent… … U. S. PATENT 960,539,
Aeronautics
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