A former coworker recently had an interesting experience.
She was renovating the bathroom in her 1940s house. She knocked out part of a wall and dozens of rusty razor blades came spilling out!
It was because the old medicine cabinets that were built into the interior walls of homes had a slot to deposit razor blades. The blades would simply fall behind the walls.
Back then you bought the blades for safety razors separately. The razor opened up and you fixed the double-edged blade inside.
