“Quite. There are four persons who know about Mrs. van Dietrich’s disappearance: My partner, Mr. Mallory, the housekeeper, and Mrs. van Dietrich’s maid. That is all. Well, there is one more--yourself, of course. We did not know that you had found it out. We don’t understand how you did it, either.” “Well, I prefer not to tell you that just now,” answered Nick Carter. “That is, if you desire me to take this case.” “We most certainly do,” declared Paul Savage earnestly. CHAPTER II. BITS OF EVIDENCE. “Sit down, won’t you, Mr. Carter?” James Mallory, who had been so interested in gazing at the great detective as to forget the ordinary amenities, offered this invitation. Getting up from his own chair behind the flat-topped desk, he placed one for the visitor, with a propitiatory smile. “Now, what is the first move, Mr. Carter?” asked Paul Savage, as they settled down. “Let me go over the particulars, as they have come to me,” replied Nick. “We will see if they agree with the information you have.” “Good idea!” commended Mallory. “To begin with, Mrs. van Dietrich was put to bed by her maid, Mary Cook, about eleven o’clock last night. The maid sleeps on the sixth floor, at the top of the house. Mrs. van Dietrich’s three rooms and bath are on the fourth.” “That’s correct,” nodded Savage. “At eight o’clock this morning, Mary Cook went to awaken her employer, according to her custom. She could not make the lady hear, and she got scared. So she went to the housekeeper, Mrs. Joyce, and told her she was afraid Mrs. van Dietrich was sick. Mrs. Joyce went with her, and, with her master key, unlocked the door, and, also, with another key, shot back the bolt.” “That’s the way I got it,” breathed Paul Savage. “Though how you managed to get it so exact----” “When the two women went into the room, they found the bed had been slept in, and Mrs. van Dietrich’s nightgown had been thrown carelessly across it. The windows were closed, except for a few inches at the top, for ventilation. This was the case in all three rooms, and the ventilator in the bathroom was open, as usual.” “There were no signs of a struggle,” remarked Savage. “So I understand,” assented Nick. “Another thing is that the clothes which Mrs. van Dietrich wore the day before went with her. She must have dressed herself--or been dressed by somebody else--before going away.” “That is all true, as I got it,” observed Paul Savage. “But there is another point, which you have not mentioned.” “And that is----” “All the jewelry in her trunks was taken out, although the trunks were locked when the maid examined them this morning. The girl had the keys.” “Oh, she had?” The intonation with which the detective made this remark caused Savage to shake his head decidedly. “I understand,” went on Nick. “You mean there is no suspicion attaching to the maid? Well, I am of the same opinion. You have not been able to find the slightest clew, have you?” “None.”