Boy, I really enjoy this volume! For people unfamiliar with the name Escher, many have, nonetheless, seen some of his more mind bending works. Many of his artistic creations have an impossibility about them--even as they look reasonable in terms of specific parts of each. Other of his woodcuts or wood engravings are enchanting in their own right.
The first part of the book is more biographical, although this segment is also richly sprinkled with examples of his work.
But it is the catalog, startng on page 176, that, to me, is at the heart of this volume. Some of the works that are especially of interest to me: (page 273) "Day and Night," in which white birds and black birds blend into one another; (page 293) "Up and Down," a mind altering look at two levels of a house that cannot be but seem to be; (page 308) "Curves and Concaves," people climbing ladders and looking through windows in a manner that leaves one's head spinning; (page 323; my personal favorite), "Waterfall," in which water flows around a structure to a waterfall, which looks fine but is impossible and one's head, again, spins!
Interested in Escher's work? This is an excellent starting point.