“Drawing an inference from the extent to which the study of birds has been directed with the view of accounting for their manner of flight, we might have been designated an Ornithological Society, except for the fact that we only study the bird as a means to an end. That end being flight, and the examples in nature being varied, we can come to one sure conclusion: that the very thin element which surrounds our globe is capable of being made a high road for the passage of heavy bodies by a mechanical and continuous attack upon the medium, based upon a knowledge, in great part yet to be attained, of its action and reaction when somechanically manipulated.