And then something did happen. On the fifth day after Matilda's departure, and the eighteenth after the sailing of the Plutonia, Mrs. De Peyster observed a sudden change in the atmosphere of the house. Within an hour, from being filled with honeymoon hilarity, the house became filled with gloom. There was no more laughter--no more running up and down the stairs and through the hallways--the piano's song was silent. Mrs. De Peyster sought to gain some clue to this mysterious change by listening for the talk of Mary and Jack and Mr. Pyecroft as they passed her door. But whereas the trio had heretofore spoken freely and often in liveliest tones, they now were either wordless or their voices were solemnly hushed. What did it mean? Days passed--the solemn gloom continued unabated--and this question grew an ever more puzzling mystery to Mrs. De Peyster. What could it possibly, _possibly_, mean? But there was no way in which she could find out. Her only source of information was Matilda, and Matilda was gone for a month; and even if Matilda, by any chance, should know what was the matter, she would not dare write; and even if she wrote, the letter, of course, would never be delivered, but would doubtless be forwarded to the pretended Mrs. De Peyster in Europe. Mrs. De Peyster could only wonder--and read--and gaze furtively out of the little peep-holes of her prison--and eat--and stack the empty cans yet higher in her bathroom--and wait, impatiently wait, while the mystery grew daily and hourly in magnitude. Among the details that added to the mystery's bulk was the sound of another new but familiar voice--the voice of the competent Miss Gardner, her discharged secretary. And Miss Gardner's voice was not heard for an hour and then heard no more--but was heard day after day, and her tone was the tone of a person who is acquainted with the management of an establishment and who is giving necessary orders. And another detail was that William no longer kept to the stable, but seemed now constantly busy within the house. And another detail was that she became aware that Jack and Mary no longer tried to keep their presence in the house a secret, but went openly forth into the streets together. And Judge Harvey every day came openly to see them. But the most bewildering, and yet most clarifying, detail of all was one she observed on the twelfth day since Matilda's going, the twenty-fifth of her own official absence. On that afternoon she was standing on a chair entertaining herself by gazing through one of her shutters, when she saw Jack crossing Washington Square. He was walking very soberly, and about the left sleeve of a quiet gray summer suit was a band of crape. Mrs. De Peyster stepped down from her chair. The mystery was lifting. Somebody was dead! But who? Who?