By this time Chick was much puzzled to know what relation this woman bore to Ellison and what her interest in the matter was. The question entered his mind as to whether or not this was not the woman who had written to Nick the two letters which had so excited their curiosity. He knew from what she had said in the beginning that it was useless to ask who she was, or what her name was, but he determined upon a sudden and bold play. “Who were you trying to strike,” he asked, “when you wrote those two letters to-day to my chief, Nick Carter?” The young woman started violently, turning to Chick in a frightened manner. “What do you mean by that? What letters?” “The letters which warned the chief that an attempt would be made to rob the Sanborns and that a woman was at the bottom of Ellison’s disappearance.” “How do you know that I wrote them?” The question was almost gasped out. “I don’t know,” replied Chick, “but I do know that the chief knows who wrote them.” “Does he know me?” “The chief knows everything,” replied Chick. “No sooner had he received those letters than he started to find out who wrote them.” “And he found out?” “Of course he did.” “And it was me?” The woman suddenly laughed a mocking laugh, and Chick knew that whether the woman had written the letters or not, his play had not counted. “If you knew as much as all that,” she said, “you would know who I am, and that’s what you don’t know.” To this Chick could make no reply, for he felt that though her first fright indicated that she was indeed the woman who had written the letters, she had now regained possession of herself and that it was useless for him to hope to surprise her into an admission. He took another tack. “What interest have you got in this matter?” he asked. “Wouldn’t anybody be interested in so mysterious a thing as happened at the Sanborns?” Again she laughed mockingly at Chick. “How did you come to know me?” asked Chick. “Are you not a celebrated person, and doesn’t everybody know Chickering Carter, the great Nick Carter’s chief assistant?” Chick knew now that the young woman was playing with him, and that he did not have easy game before him. “No,” he said, “I am not so celebrated in the circles in which you move that you would know me.” “What do you mean by that?” asked the young woman. “I mean that you saw me for the first time to-day, and that it was at the Sanborn house where I was on duty and you were there as a guest.” By the way the young woman took this reply, Chick knew that he had scored a point, but did not know how much of a one it was. “Did you see me there?” she asked. “Not that I recollect,” replied Chick. “Perhaps it is very wrong for me that I should have failed to observe so charming a person as yourself.” “None of that, please,” sharply returned the young woman. She was silent a moment, and then said: “Yes, I was there, and one of the few who knew that Mr. Ellison left the house.”