We all know that if you don't learn your history, you're doomed to repeat it. In the case of most of these rare historical photos, you really don't want to repeat them. School does a pretty good job of covering the basics, but these black and white photos uncover sides of our collective history on earth that often go unseen. Some are disturbing, but they're all fascinating. Take a look. 1.) Not a hatless head in this crowd of New Yorkers in 1939. 2.) The Punt Gun: able to shoot over a pound of ammunition in a single shot and...