In "The Little Cloud," why does Chandler shout at his child, and how does this action sum up the story?

In "A Little Cloud," Chandler is presented as a man of little talent, little self-confidence, little capacity for achievement, and little emotional maturity. After an evening visit in Dublin in which an old friend trumpets his real, though perhaps limited successes, in Paris and regales Chandler with vulgarity, coarseness and materialistic ideas, Chandler reaches the end of his self-deluding composure. When he gets home, after having had his ego and one remaining vestige of hope trampled to death by his friend Gallaher, Chandler's wife scolds him for being late and orders him to take care of the baby while she runs an errand. Chandler tries to console himself by reading poetry--only to remind himself that it is his secret wish to write poetry and not to read it--but is interrupted by the baby's cries. Chandler tries the unsuccessful tack of trying to rock the baby while he reads but only finds himself more heartsick and irritated.

After an evening when his soul and psyche have been abbraided by Gallaher's boasts and visible success; after having his wife bring home his bitter unhappiness over his marriage to a domineering and insensitive wife (maybe just a busy wife with myriad important responsibilities, like the well-being of a baby ...); Chandler finds the abrasive and domineeringly demanding crying of the baby and the abrasive interruption of his one source of solace (poetry) to be one thing too many to endure and he loses his temper and loses his sense of reality and screams horribly at the baby until his wife rescues the infant. Thus the ending illustrates how Chandler has constructed his life (without a clear sense of reality) and simultaneously  illustrating Chandler's tolerance for the life he has constructed (nil).