E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Eagle (for lecterns in churches).
The eagle is the natural enemy of the serpent. The two Testaments are the two outspread wings of the eagle.
Pliny in his Natural History (book x. chap. 3) enumerates six kinds of eagles: (1) Melænactos, (2) Pygargus, (3) Morphnos, which Homer (Iliad, xxiv. 316) calls perknos, (4) Percnopterus, (5) Gnesios, the royal eagle, and (6) Haliæetos, the osprey.