Beneath each of the sixteen spouts are eight sirens with outspread wings, hands resting on their chests, alternating with eight ithyphallic satyrs. Sirens are typically charged with ambiguity: their song brings joy, foresight, and death, yet they are also guardians of the memory of the deceased and guides to the afterlife. According to Pythagorean doctrine, their song—composed of the eight notes produced by each siren—forms the harmony of the celestial spheres, which are comprised of eight heavens.