We all have our own habits when it comes to reading books. I, for one, use a laminated bookmark to get back to the page where I left off. Others not so much, I suppose, as one librarian just found a half-eaten cookie in a 1529 edition of a manuscript. The cookie was found inside of a copy of St. Augustine dating back to 1529, and the library posted the photo with the caption: "Today's unexpected discovery in a 1529 volume of Augustine. For future reference, we have acid free paper to mark your place. Please don't use baked goods." Fair! The cookie is believed to be from about 50 years ago.