License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Mathäus Küsel. A grotto with collapsing rocks, opening to a sky full of the enthroned gods of Olympus, including Jupiter, Apollo, Mars, Venus, and Mercury; set design from 'La Monarchia Latina Trionfante', 1678. The Metropolitan Museum of Art.