An earlier view of the Institute for Paradoxical Shadows. It is developing the full size implications of instrument Six, shown below.
To view the floating shadow make sure the image is small enough to register the shadow in the left image over the one in the right hand image when you go cross-eyed (you will see three images – concentrate on the middle one). Try to relax to get a good three-dimensional view. You will see that the shadow sits a short way off the surface in which you would expect it to land.