Final 幻想 Crystal Chronicles: Echoes of Time on 任天堂 DS - Need Help!!

I'm done with saving the little girl, I'm at the 图书馆 and the southwest door is open. I've killed the guy there and this thing showed up west in the room. I picked up the book and layed it on the marble. Nothing happend. Just this sirkle following me, nothing more. Then I tried to hit the thing and it was... hittable. Anyway, I tried that thogether with laying the book on the marble, but this didn't work either. And now I'm stuck.

I can understand a part of it is my fault, for choosing Very-Hard. But still I'd be glad to find out what happend here. So if 你 have an idea, please inform me! Thank you! ^__^