7. Perspective Machine
Connect the pointer on the left side, through the frame to a place on the stack of books on the right side of the piece. The pointer shows where that area on the stacked books would appear on the picture plane, the area in the frame if it held a canvas.
The bas relief picture of the books, hanging above and a bit left of the machine, is the same view as seen through the picture frame with the pointer.
You will notice that looking at the stack of books from a different perspective reveals objects which are concealed by overlapping objects in the framed perspective. For example as you stand in front of the book shelf you can see an additional book and a small animal not evident in the picture as seen through the picture frame.
A picture is limited to one perspective. The only objects that will be seen in the upper left bronze picture are the objects that can be touched by the pointer.