These scans of an old safety booklet for children called It's Great to be Alive! are full of gruesome injuries that befall careless bicycle riders, pedestrians, and kids at play.
In fairness, adults didn't have a lot of options in those days, so using abject fear was a common parenting tool. There were no reflective bicycle helmets or knee-pads for skateboarders, no designated bicycle lanes, many fewer supervised activities, and we didn't even have seat belts in cars until the mid-1960s. When accidents happened, they were usually pretty grim.
See more mayhem in this article from Gene Gable. Link -via TYWKIWDBI