For the longest time I was sure I possessed first editions of at least two books -- To Kill A Mockingbird and Till We Have Faces.
The latter book I picked up at an Antiquarian Book Fair at a fairly exorbitant price, thinking it was a first edition of a book I dearly love. Well, I still love it, but alas, I was chagrined to find that it is, in fact, NOT a true first edition after applying some of the tests demonstrated in the video-clip, below. Both of these books are stamped with the original publication date inside [1960 and 1956] but they are not first editions, as I had thought they were. Goll darn it!
How about you, dear reader/collector/book-omnivore? Are you also harboring interlopers on your bookshelf? A little pot-light illuminating the spine of a "first-edition" that is all the while a third-printing? Not that I have any desire to knock the wind out of your sails, but take a few minutes to watch this video-clip and then have a second look at your own treasures to see if they measure up.