The Art of Money Getting or Golden Rules for Making Money by P. T. Barnum (1880)
That PT Barnum... it's interesting because it really is a good read, and the whole way through you do feel like he's giving you some kind of good advice (so, if you had purchased it back in the day you don't feel ripped off), but at the same time it's not really practically actionable. You won't actually get closer to being like PT Barnum (even if you were reading it in the 1800s) or understand the steps to becoming like him, or necessarily become any better at making money. But at the same time, you're satisfied enough with the read to feel like you hadn't wasted your time and money on it. That's his real trick :)