ION, SINCE 1891. + L. Hargrave, of Sydney, Australia, inventor of the cellular kite and hopper, which are learning to fly. more than a score of successful acroplane models, Since 1891, when Lilienthal, after, twenty years of Lilienthal proved that a slightly convex surface of + Pénaud, in 1871,… … by Capt. Ferber.
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