Knock knock, what was that book?

April 14, 2014 2:18 PM

Please help me find a mystery book from my childhood. I am stumped. It would have been in the mid 70s, probably between 1974-77. I think it was science/nature-related book that may have been one of a series. What I remember is a hard-cover book, and on the back inside cover there was mounted a round plastic disk with an arrow inside, sort of like a compass. It was visible though holes in the pages and front cover. There were questions with multiple choices on each page, and you would close the book and knock on the cover a certain number of times to make the needle point to the correct answer on a corresponding page. That sounds crazy even as I type it, but if someone could find this book (or even corroborate my memory) I would be eternally grateful.
posted by mefireader to Grab Bag (2 answers total)

Best answer: Something like this: http://www.ebay.com/itm/The-Amazing-Magic-Computer-Book-2-1968-Disc-Gives-You-The-Answer-With-a-Tap-/141251378827?pt=US_Childrens_Books&hash=item20e33cfe8b
posted by at at 9:53 PM on April 14, 2014

Response by poster: WOW, that has to be it! I didn't remember "computer" being in the title, and I was wrong about the hole extending through the front cover. But the arrow inside looks totally familiar, and the premise is exactly the same.

Another years-long mystery solved in a day on Ask. Thanks, at!
posted by mefireader at 10:28 AM on April 15, 2014 [1 favorite]