An image of Miss Mary McCandlish by David Octavius Hill, Robert Adamson, (I know absolutely nothing about this woman, but she looks a bit.creepy to me. As if the secret she knows is about the bodies buried in the garden. Gives me the shivers.
One of my favorite things that was shown to me during my elementary age years was an optical illusion. It was the very famous Rubin Vase (pictured below) which you can see in either two ways - as a vase or as two faces that are facing each other.