the son of Vulcan, was a giant of prodigious size, who dwelt in a cave on Mount Aventine, whence he issued and plundered the surrounding country. When Hercules was returning to Italy with the oxen he had taken from king Geryon, Cacus stole some of the cattle while the hero slept; and in order to prevent discovery, he drew them backwards by their tails into his cave. Hercules, however, was attracted to the spot by their bellowing, and slew Cacus with his club. According to another tradition, the place where the oxen were confined was revealed by Cacia the sister of the robber. In commemoration of his victory, Hercules erected the *Ara Maxima*. Ovid, *Fast.* i. 554.