Linked below is an old advertisement for a “shoe-fitting fluoroscope” -- essentially, an X-ray machine used to look at the bones of your foot in order to judge your shoe size.
As little as 60 years ago, these devices were pervasive and thought to be harmless. But by the early 1950s, a number of professional organizations had issued warnings about the continued use of shoe-fitting fluoroscopes -- some thirty years after they were invented and routinely used. Today we know how risky and carcinogenic X-rays can be. One shoe model received such a serious radiation burn from a shoe-fitting fluoroscope that her leg had to be amputated.