Do. how to construct to evade the superimposed air during the up stroke, [241]
Do. can be driven at any speed, [251], [255]
Do. can create currents and rise upon them, [253]
Do. can make new currents and utilize existing ones, [251], [255]
Do. as a propeller, [256]
Do. as an aërial screw, [256]
Do. forces required to apply to the air, [245], [246]
Do. necessity for supplying root of, with elastic structures, [247]
Wave wing, compound, [242]
Weight necessary to flight, [110]