License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Salomon de Caus. Problem XXIIII: A Machine for a Moveable Galatea in a Grotto, in: Les Raisons des Forces Mouvantes, plate 32, 1615. The Metropolitan Museum of Art.