What makes this book of "spot the differences" puzzles so unique? Simply put: the quality of the photographs. Every one of the pictures comes from the acclaimed George Eastman House archive, with some dating back to the 1800s. So they make stunning art as well as absorbing brainteasers. In every case, you'll get two versions of the picture side by side; they'll look almost alike, but one is slightly different from the other. It's up to you to search the images and find the variations. The puzzles come in three levels of difficulty: easy with five differences, medium with six, and hard with seven. The photographs encompass historical figures, famous buildings, stunning landscapes and engaging animals and many are iconic works by renowned photographers. The most famous include "The Migrant Mother" by Dorothea Lange, Lewis W. Hine's "Power House Mechanic" and the amazing portrait of Abraham Lincoln taken by the celebrated Civil War photographer Matthew Brady.