The Swing of the Pendulum is a short story by Katherine Mansfield: The landlady knocked at the door. - "Come in," said Viola. - "There is a letter for you," said the landlady, "a special letter" - she held the green envelope in a corner of her dingy apron. - "Thanks." Viola, kneeling on the floor, poking at the little dusty stove, stretched out her hand. "Any answer?"