 At the top of the lighthouse's stone tower is a set of mirrors which can rotate via a large stone dial, labeled with numbers and in some cases the names of the "candidates".Jack is able to see an image of his childhood home reflected in the mirrors when they are turned to his number, 23; whether this is due to some property of the lighthouse mirrors and structure or simply to Jacob's influence is unclear.There are ruins on the Island, many with hieroglyphs.