Line: The book shelf in the room shows the use of line because the book shelf shelves are built against the wall forming a miniature tree. Our eyes are drawn to look at the book shelf tree from bottom to top and outward to the tree/bookshelf branches.
It is a great idea if you have a stairway or long hallway. I have one whole wall of pictures of my family in my livingroom like this above the piano. Dream Home,For the Home,Home Sweet Home,There's No Place