JF Ptak Science Books
This is another in a series of posts on images found in the glorious Fr. Athansius Kircher's masterpiece, Mundus Subterraneus, printed in 1668. (One of the main posts on these images occurs here; there are many more if your search under Kircher's name in the Google box at left.)
This fine example of the depth of his observation finds the great Jesuit finding things in rock and mineral samples like agate--in this case he looks at a collection of samples that display found letters of the alphabet and geometrical shapes.
This image is 15x9 inches, and printed in 1668. $300