I bought this book because I'm an animator and thought it might come in handy. I wasn't wrong! You can learn a great deal about motion and how the body moves from looking at the sequences in this book. It's quite dated though and some pictures are hard to make out properly but it's still a great tool to have if you ever get stuck with something or if you can't find a good enough video reference anywhere.
Vital. Over a century later and Muybridge's sequences are still (why?) the best published material for the study of the mechanics of human and animal figures in motion. Contrast and sharpness are very good throughout; you can see clearly which muscle groups are working hardest in a given action.