The position of the black cat sitting on the table keeps changing, each time the camera comes back to show the cat. (approx 5 minutes in).
John (Joe) comes upstairs from the bookstore's cellar with a pile of encyclopedias, topped with a small potted plant. He drops the books and plant. He and the girl bend over to pick them up, putting them on the corner of the table. The plant is nowhere to be seen during this shot, and there are books on corner of the table. In the next shot, the plant mysteriously appears on the corner of the table in front of the books.