The New Student's Reference Work/Io

Io (ī′ō), a character in Grecian mythology, was the daughter of Inachus, king of Argos. She was beautiful, and soon won the love of Jupiter, the Grecian god of the sky, who on account of the jealousy of Juno, his wife, changed Io into a white heifer. Juno appointed Argus, “the all-seeing one,” who had one hundred eyes, to watch over her. Mercury, the winged god, was commissioned by Jove to carry off the heifer, and he slew Argus, first charming him to sleep by playing on the flute and then cutting off his head. Juno used the eyes of Argus to decorate the peacock's tail. Afterwards, by the request of Jupiter, Io was restored to her former shape, and married King Osiris. After her death she was worshiped as an Egyptian deity, under the name of Isis. The story is given in the Prometheus of Æschylus.