Have you ever taken a spitball to the eye? Hurts like the devil.
This is honestly one of the safest jobs you could possibly have. You aren't teaching at the high school level, so you don't have to worry about teaching in an inner city where some of the kids might be bringing weapons to class. That's not a big concern in a university. You don't even have to worry about some of the soreness and eye strain issues that most 9-to-5ers have from living a sedentary lifestyle, as you're up on your feet just enough to keep the blood flowing. And you're teaching history - come on. Unless Attila the Hun suddenly comes to life, leaps out of a textbook and comes at you with a battering ram, we think you'll live.