Aëronautics: an abridgment of aëronautical specifications filed at the Patent Office from A. D. 1815 to A. D. 1891 (1893)
Brewer, Griffith, comp, Alexander, Patrick Y., joint comp, Great Britain. Patent Office · London, Taylor and Francis · leaf 98
87 a like purpose, and oscillating beams, which are provided … A.D. 1881. No. 1879. HUTCHINSON, William Nelson. " Balloons." The elevation of balloons is regulated by tightening the envelope, and thus compressing the gas. The net is extended below the balloon and drawn together at the zone by pulleys, thus compressing the balloon. Elongated balloons are…
Aeronautics
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