Magic map or jigsaw puzzle

Just before I set out from Baba Yaga's to walk to Duwamish, Baba Yaga presented me with this map. "It's a magic map", she explained, "if the map falls into the wrong hands nobody will be able to read it for, as you can see, it is made up like a jigsaw puzzle and the pieces will move of their own accord into the wrong place. The blue pieces represent Memnosyne Stream which will make anybody other than yourself forget they have seen it afterwards. Of course, when in your hands the pieces will always be in the right place. From the stream you will always be able to find your way". I thanked her profusely for this unexpected gift and tucked it away carefully. I wasn't expecting to have to use it, but you never know .....