After the disappearance of Homer Barron, perhaps in order to reestablish herself as a lady as well as to have a source of income, Emily teaches china painting. That she is reestablished partially by the Old South is evidenced by the "daughters and granddaughters of Colonel Sartoris' contemporaries" being sent to take lessons although they are sent as small charitable donations: "they were sent in the same spirit that they were sent on Sunday with a twenty-five cent piece for the collection plate." This return of Emily's to Old South society is also evident in the next sentence: "Meanwhile her taxes had been remitted."
However, after the new generation, the new South became the "backbone and spirit" of the town and the painting pupils grew up, Miss Emily's front door closed for good. She rejects the New South by not allowing address numbers to be posted above her door. The illusion of the Old South has gone for good just as the china painting is ended. Like fine china, Emily has broken and dies, her grey head on a pillow yellow and moldy with age.
Do we know how many years she taught china painting? The narrator tells us that, when they tried to get her to begin paying her taxes, a "deputation waited upon her, knocked at the door through which no visitor had passed since she ceased giving china-painting lessons eight or ten years earlier."
Does her having taught china painting have an impact on the story? I don't think so. The word "impact" is too strong. Her buying the arsenic has an impact because it serves as a clue to how Homer Barron died. The foul odor around her house has an impact because it tells us to expect an explanation for what caused the big stink. But china painting is not something that moves the plot. What it does do, however, is give us one more indication of how old-fashioned and set in her ways Emily is.
An article in The New York Times reports, "By the 1890's, china painting was a national phenomenon, a do-it-yourself craze that hundreds of thousands of women across America joined for pleasure or profit." Women would buy plain, or blank, china vases or plates or cups and then paint their own designs. When mass production of pottery and china was introduced, prices were reduced and more people were able to buy full sets of china. The art of china painting became less popular and was considered old fashioned.
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