I bought this book from my local library book sale, and I was intrigued by the cover. I finally got around to reading this book, and I was pleasantly surprised by how good it was, especially considering the time period it was written, (the late 1960s). This book is filled with a bunch of little riddles, optical illusions, challenging math problems, and really nice illustrations.
There are some really clever puzzles in this book, and there are a bunch of really good illustrations included, (most of them featuring the devil). It makes me wonder if this book paved the way for Quirkology and other popular YouTubers. I will admit that some of these puzzles were a bit far-fetched, or didn't make a lot of sense, and there were a few that I couldn't figure out, even with the answer key in the back. Also, the age guesser at the end of the book was able to guess my age, (all-be-it, one year off). Overall though, a really good book, especially for the time frame this was written in. I'm surprised there aren't many ratings for this book, but that may be because it might be hard to come across. Glad I got it from the sale!