"I harm no one, sir," she murmured. "I only wish to be let alone that I may complete the work of vengeance which I have begun against the man who has brought so much misery to me and mine." "Just so, madam, just so," answered Caleb Hook, soothingly. "You refer to Mr. Callister, no doubt, who is now in the room below. I stand ready to help you in your work if I can." "But you are the detective who arrested my--Frank, I mean." "I did, but I have stood his friend from that night until now. I am anxious to help him and all belonging to him. Are you not the person to whom I spoke at the Trinity church-yard wall on the night of the arrest? Did you not tell me that Frank Mansfield was your son, and that he robbed the Webster bank?" "No, no, I was mistaken. I was mad!" exclaimed the woman, springing forward wildly. "I have no son, he robbed no bank. Go away and leave me alone." "'Tain't no use to make him mad, missus," whispered the newsboy. "Frank trusts him an' I guess the best thing will be for us to trust him too." "You are right, Jerry," said the detective quietly. "Neither this good lady nor yourself have anything to fear from me." "Ha! ha! ha! Ha! ha! ha! You can just bet your life the detective will never get into this little racket--never in the world." From the room below these words, accompanied by loud and boisterous laughter, suddenly burst forth, the sound finding easy passage through the uncovered stove pipe hole in the floor. The effect upon the woman was electrical. Advancing quickly toward Caleb Hook, she grasped him by the hand. "That's his voice," she whispered wildly. "Help me to bring that man to the hangman's scaffold and I'll fall down and bless you on my bended knees. It is Elijah Callister that robbed me of my husband; it is he who robbed me of my reason, and would have robbed me of my son. Oh, if I could only trust you, sir! If I could only trust you! How can a weak woman like myself, with no other help than that of this faithful boy, hope to bring justice upon his sinful head alone." "You may trust me fully, madam. I too have a grievance against Elijah Callister. Will you help me to bring him into the grasp of the law which he has so long defied?" "Yes--yes! Let them hang him as high as Haman! Oh, that I could only dance on his grave!" She spoke wildly--excitedly. That her mind was far from clear was plainly to be seen. That she hated Elijah Callister with a deep and bitter hatred was equally plain. Caleb Hook, watching her closely, saw all this, and understanding that his opportunity had come, proceeded to grasp it at once. "Tell me what you know, and you shall do it!" he said, emphatically. "I swear that your desire shall be fulfilled! Who and what is this smooth-spoken Callister--that's what I want to know?"