When you look through the hole, at first all your eye registers is blue.

Then you realize that the inside of the box has been cleverly painted blue in places, so that it looks like white clouds in a blue blue sky. The light coming in through the study window suffuses the clouds on one side, making them otherworldly and transcendent.

You cannot see anything that would have made the rattling sound you hear when you move the box.

As you are thinking this, a sudden hot gust of wind seems to come out of the box and blow right in your face.

You close your eyes reflexively as the wind increases in strength, blowing all around you.