A pocket watch

Inside the box is an old fashioned pocket watch on a long silver chain. For a moment you think it might be a valuable antique but closer inspection reveals it is just old. It's scuffed and dented, most of the gold plate worn away by use. Popping the cover open you find it is still ticking though, it even has the correct time. Along with the watch is a battered paperback book. Turning it over you read the title....