License, verbatimPD
The National Gallery of Art: open access image with no usage restrictions under the NGA's open access policy (openaccess=1 in the Gallery's published_images dataset).
Giuseppe Vasi, after Paolo Posi. The Prima Macchina for the Chinea of 1753: The Temple of Asclepius with the Chariot of the Sun, 1753. National Gallery of Art, Washington.