It's not easy to remember life before Photoshop. When we do, we think of a world where picture were straightforward, always showing exactly what happened to be in front of the lens when the exposure was taken. But that's not entirely the case.
Trick photography has been around for centuries, and even though the folks in Victorian times weren't nearly as concerned with artificially slimming down, they did like to have some photographic fun once in a while. This set of headless photographs from the 19th century is a great example of the kind of 'fun' we're talking about.