Animal Locomotion; or, walking, swimming, and flying / With a dissertation on aëronautics

by James Bell Pettigrew

Fig. 119.

Fig. 119.—The same cane when made to vibrate more rapidly. In this case the waves made by the cane are less in size, but more numerous. The cane is seen alternately on either side of the line x x, being now at i now at m, now at n now at j, now at k now at o, now at p now at l. The cane, when made to vibrate, has no dead points, a circumstance due to the fact that no two parts of it reverse or change their curves at precisely the same instant. This curious reciprocating motion enables the wing to seize and disengage itself from the air with astonishing rapidity.—Original.

Fig. 120.

Fig. 120.—The same cane with a flexible elastic curtain or fringe added to it. The curtain consists of tapering whalebone rods covered with a thin layer of india-rubber. a b anterior margin of wing, c d posterior ditto.—Original.