se non ricordo male devi solo saltare sulle varie pedane
edit:
soluzione da gamefaqs
Kill Mrs Mad and move one of the barrels onto the switch. Now use the rune on
the gate and kill Mr Mad. Go down the stairs. Go to the right of the room and
3 werewolves will come out of the hole in the wall. Kill them and the door to
the right opens. Go through. Kill Mr Mad and go up the stairs.
In here, kill Mr Mad and read the book. Go through the door to the right and
kill Mrs Mad. Move a barrel onto the switch again, and then jump up on the
cupboards, to get to the Earth Rune in the corner.