Adelaide responds tartly to her brother's insincere concern about the cost of their mother's clothing, imbuing her speech with verbal irony:
"Mother must be provided for properly,” her son declared. “How much ought it to cost—a year—for clothes?”
“You know what your wife’s cost,” suggested Adelaide, with a flicker of a smile about her lips.
When Adelaide tells James “You know what your wife’s cost,” she’s subtly pointing out her brother's capacity to afford their mother's needs. James is pretending to be ignorant of how much money it costs to provide for an upper-middle-class woman. Adelaide knows he’s actually familiar with this cost, considering the expenses he incurs for his wife’s clothes as a member of the social elite. This comment, underlined with a “flicker of a smile,” insinuates that the amount James spends on his wife's clothing is probably quite significant. Therefore Adelaide’s retort implies that he should have no issue ensuring their mother is equally well cared for. The irony here lies in her indirect way of highlighting her brother's wealth. He’s pretending not to understand her because he doesn’t want to take on the additional expenses. Adelaide’s knowing response destabilizes his seemingly earnest query about the cost of making sure Mrs. McPherson is “provided for properly.”
