Spooky windows

A few days ago, while up in the attic checking the water level in the bucket above the room that J, a German girl living with us for six months, sleeps in, Hubby noticed weights on a pulley hanging near him. He realized this mechanism was what operated the window in J's room ... and J was currently in her room. 
With her headphones in and music playing loudly.
She had no idea we were outside her room, and especially no idea Hubby was above her ceiling.

As I observed from the top of the ladder, Hubby reached over to the weights and pulled them down slightly.
He released his pull and allowed the weights to go up.
He pulled down.
He let them go up.
Hubby did this three or four times, both of us snickering, and I was just waiting for J to come barrelling out of her room (I mean, if your window began to go up and down on it's own, wouldn't you?). 
As it was, she did not come out of her room ,and I actually forgot all about it until several hours later when, during milking, I inquired about the activities of her bedroom window.
It turns out that J had been quite frightened, but at the same time thought it was just one of those things that happens in an old house. 


Personally, I would probably have peed my pants.