12. Jacques Fabian Gautier D’Agoty, Observations sur l’histoire naturelle, sur la physique et sur la peinture, 6 vols., Paris 1752-55, Tortuise, Observation XII. Three-color mezzotint, 20.5 x 14.6 cm. Yale Center for British Art, Paul Mellon Collection. Detail, bottom right corner, showing evidence of second plate.