The library at 7pm, when it turns into a ship

I keep trying to fall asleep and my brain just keeps putting me back in this one image: the whole library starts listing to one side, like it's heaving on a swell, and all the reading lamps swing together and the shelves stay perfectly upright and nobody except me seems to notice. We're just an hour from land, is all. I don't know if I'm the librarian or the passenger, but I'm not scared. The dust motes just look like they're falling the long way down.