A quick tale today that I heard on QI (Series J, episode "Just the Job").
TRIGGERS FOR CHILDBIRTH/GROSS MEDICAL STUFF
Chainsaws were originally invented for cutting a woman's pelvis if she was having difficulty giving birth. In 1783, Scottish doctors John Aitken and James Jeffrey would perform a "symphysiotomy", a procedure to widen the pelvis if the baby's head as too large to pass through, using a device called an "osteotome".
The chain used was like a watch chain. This device was later used to remove other parts of diseased bone, for example in the arm, which would result in it becoming stiff. The chainsaw that we are now used to, for cutting down trees, was invented in 1920.
You will never look at a pocketwatch the same way.
I watched this episode and went, "ABSOLUTELY NOT" and turned it off. Because it's been sitting in my brain for several days, I have decided to purge the mind-squick, and everyone knows you can only get rid of mind-squick by sharing it with others.