PLATE II 98 Haenlein’s Gas-driven Dirigible. Wölfert’s Benzine-driven Dirigible. Santos-Dumont’s Dirigible, _No. 16_. PLATE III 116 The _Lebaudy_. _La Patrie._ Lebaudy’s _Morning Post_. PLATE IV 124 _La Ville de Paris._ _Colonel Renard._ PLATE V 128 _Zodiac III._ _Zodiac IV._ PLATE VI 130 _La Belgique._ Italian Military Dirigible _No. I bis_. PLATE VII 132 _Clément-Bayard I._ _Clément-Bayard II._ PLATE VIII 138 _U. S. Signal Corps Dirigible I._ _Gross II._ PLATE IX 140 _Parseval I._ _Parseval II._ PLATE X 146 _Gross III._ Zeppelin Airship Structure. PLATE XI 160 Zeppelin Dirigible Resting on the Water. Zeppelin Dirigible over Zürich. PLATE XII 182 Henson’s Aëroplane. Ader’s Aëroplane. PLATE XIII 186 Stringfellow’s Aëroplane (Front). Stringfellow’s Aëroplane (Side). PLATE XIV 192 Phillips’s Tethered Aëroplane. Phillips’s Aëroplane. PLATE XV 194 Langley’s Steam Model. Langley’s Gasoline Model. Langley’s Two Surface Gasoline Model. PLATE XVI 212 Lilienthal’s Monoplane Glider. Lilienthal’s Biplane Glider. Pilcher’s Monoplane Glider. PLATE XVII 218 Chanute’s Five-Deck Glider. Herring in Chanute Biplane. Herring’s Compressed-air Biplane. PLATE XVIII 226 Maxim’s Aëroplane. Langley’s Large Aëroplane. PLATE XIX 246 First Wright Glider. Second Wright Glider. PLATE XX 248 First Wright Aëroplane (Rear). First Wright Aëroplane (Side).