...he ground and he unfolded his scheme for demoralizing and driving away Grant's army. He had just invented an airship. In shape it was something like a bird, and for that reason he had called it Artis Avis , or, The Bird of Art, which was the meaning of the two Latin words. The frame was made of hoop-iron and wire. It was covered with white-oak splints. It was to be run by a one-horse-power engine...