Bella tries to get out of the letter-named-rooms building to go ask Emily for directions, but that's not a stairwell after all, and there's someone shouting at her not to come in and she flinches back and clonks her elbow on the door and boots or no boots she's down and she -
- is falling -
"All right, I changed my mind about which safe spell is next. I had better not go in the palace because your mother might spot me; can you bring out the scroll from the safe pile titled 'Prestidigitation', from my room?"
"Good," she says, "I am very proud of you, I bet that was hard. So what this spell does is, while it's running, it lets you do all kinds of silly little things. It isn't very strong or fast or complicated, but you can control it with your will. And it lasts for a whole hour."
"It can move things - only about as well as I can move things with telekinesis, which isn't much - and change their colors, and conjure flimsy objects that aren't good for any practical purpose, and it can clean things or dinge them up again, and it can do gentle temperature effects and change the flavors of things, and most of this stuff disappears after the hour's up although cleaned things stay cleaned and moved things don't go back where they were."
"I don't know. I think a full treecycle is close to a day and there are twenty-four hours in a day. The sound illusion spell lasts six seconds for people who aren't better than me at wizardry and sixty seconds is a minute and sixty minutes is an hour."
"Do you think it will work better if I mention it before, or after you sit playing with a prestidigitation for an hour?"
"Yeah, it's not really about being quiet or even still, it's about not doing anything effortful."
"I guess effortful's not the thing either. Restful. I assume you're pretty quiet and still when you're sleeping, however little you do it, and the closer you're behaving to as-though-you're-sleeping the better."