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.
Looks to me like this one's about to go on a "donkey walkabout" as I call them. My Chloe learned from my departed Nutmeg how to watch humans work locks on gates, etc. and then open them herself. I now have to use donkey-proof closures always.