I don’t know hoe many saw the History Channel program on why state boundaries were drawn the way they are but it was interesting.
Several states’ boundaries were drawn the way they are for the Transcontinental Railroad.
And then there were the miners.
There was a special mine car (I think there’s a Gn15 version at Ozark Miniatures) for miners when they had to take a trip to the bathroom.
Miners carried a chain in their pocket and when nature called they’d take the “Thinder Bucket” down the tracks for privacy. They would put the chain in front of the mine car’s wheels to keep it from rolling down the tracks. But miners were jokers.
They would sneak down the tracks and remove the chain, giving the miner a free ride.
If the miner heard them coming he’d yell, “Don’t pull my chain!” And that’s where the expression came from!