A German Volksbuch ("folks book") story tells about the difficulties that the citizens of Schilda had, as they were trying to illuminate the interior of their council house.

They went to the extreme of going outside with all types of baskets and bags, in order to collect as much sunlight as they could, and carry it inside the house.

Since that did not work, they also tried removing the house roof. This worked perfectly, until the winter came.

One day, a Schilda man accidentally hit himself against the wall on the way out of the council house. This caused a ray of light to enter inside the house through a tiny wall fissure.

And this is how the Schildans came to think about windows. That simple part of a house, the story says, was never invented but found by mere accident...