If you live in an old house, your bathroom wall might be full of razor blades

If you live in a house that was built between the 1920s and 1970s, the inside of your bathroom wall might be filled with dusty old razor blades.  If you have a medicine cabinet, look to see if yours has a slit in it. These slits were used to get rid of used razor blades before disposable razors were popular.

Putting the razor blades inside of the wall rather than the trash protected sanitation workers from getting injured. There was no box or container to catch them, the razor blades would just fall down inside of the wall and remain there until the house was reconstructed or torn down one day. I have a medicine cabinet with a slit, and I'm both intrigued and a little creeped that a pile of strangers' used razor blades are sitting inside of my wall at this very moment.