INDEX.
PAGE
Aerial creatures not stronger than terrestrial ones, [13]
Aërial flight as distinguished from sub-aquatic flight, [92]
Aëronautics, [209]
Air cells in insects and birds not necessary to flight, [115]
Albatross, flight of, compared to compass set upon gimbals, [199]
Amphibia have larger travelling surfaces than land animals, but less than aërial ones, [8]
Artificial fins, flippers, and wings, how constructed, [14]
Artificial wings, Borelli, [219]