Audubon's "The Birds of America"

Those are not miniature books in the photo.  The top five books represent the complete first edition of Audubon’s Ornithological Biography. Underneath them is "The Birds of America."

Considered a masterpiece of ornithology art, the 3½ -foot-tall books feature hand-colored prints of all the species known to Audubon in early 19th century America. Audubon insisted on the book’s large format — printed on the largest hand-made sheets available at the time — because of his desire to portray the birds in their actual size and natural habitat.

This book size is referred to as a "double elephant."  See this 2010 post for an explanation of the terminology (and an old photo of one of the books opened).