well it took me a min to find out this answer as well there is a cave towards the bottom
of the wall to the left of the house the key to getting down there is making sure u follow
the whale closly so that your air meter is kept at least half full or u will not make the
swim into the cave at the opening of the cave they supply u with the blue lums of air but
u have to swin quite a bit be they give u another once your in so ......good luck