The narrator also compares Tess to a "fly on a billiard table of indefinite length and no more important to its surroundings than that fly." By comparing Tess to a fly he is saying that her life is small and unchanged by her environment, as she works on a huge farm and has no real importance, just like a fly. The narrator also states right after that quote that she is very much like a heron, with no real importance to the valley. She and her environment are not influenced by each other. The only reason Tess has changed is that her spirit has become duller. The narrator describes that "Tess followed him slowly into the back." Tess has changed to follow the pragmatic but lethargic routine of life on the farm and is going through the daily motions to overcome difficulties