What about the marbles in Burl Ives?
You've got me on that one.
I have kin that was a brand new Navy Doc, WWII.
He was the ships Doctor when a sailor was injured.
While they are getting everything ready he is looking at his books! Being an ophthalmologist, this was not what he was trained in.
At a ship reunion a few years back, the sailor told him everything healed just fine.
The ‘marbles’ always remind me of that event.