Picking Rooms Part 2

I was brought to the fourth floor by a magical elevator that went between the floors. Well, they call it a lift, but to me, it's just an elevator. When it stopped at the fourth floor, we exited to stand in a small room just big enough for ten people. There was nothing else but four white walls. 

"Young Miss, please place your hand on the wall here and inject your magic into it. It is already waiting for you to register with it." Jeeves explained, which made me nod my head. I guess this was what you call a secret mechanism that brought you to the real room.