Nick broke off abruptly, wheeling sharply around to gaze in the direction Miss Margaret Hanson had taken. She had disappeared. Neither in the driveway, the adjoining grounds, nor in any part of the near avenue, was there any sign of her. Nick Carter’s strong, clean-cut face underwent a decided change. He turned to Patsy, saying hurriedly: “By Jove! This may be a put-up job. Get a move on, Patsy. Hunt up that woman who fainted. Find her, if possible, and keep your eye on her.” “You think----” “A child in charge of that nurse may have been stolen. The woman’s fit may have been only a trick to lure the nurse away while----” “Holy smoke!” Patsy interrupted. “I’ve got you.” He darted away at top speed with the last in search of Margaret Hanson. Nick already had turned, and was hurrying toward the distracted nurse, who still was seeking here and there like one bereft of her senses. Tears were streaming down her cheeks when the detective approached her and grasped her arm, saying firmly yet kindly: “Come, come, my girl; calm yourself. What’s the trouble?” “It’s Amy, sir,” moaned the girl. “I can’t find her.” “You left her here?” “Yes, sir, when I went to aid that woman. I told her to stay right here and tend the baby. Oh, I must find a policeman, and----” “Stop a moment,” said Nick, detaining her. “I can do more than a policeman. I am a detective. Compose yourself, now, and tell me just what occurred. I will help you find the child. How old is she?” Glancing sharply around, Nick had seen plainly that the child would be easily discovered unless she had strayed to a considerable distance, which was quite improbable in the short time the nurse had been absent. The circumstances, moreover, already led him to suspect something far more serious. Somewhat encouraged by his assurances, the nurse governed her agitation and hastened to reply. “Amy is six years old, sir.” “How long had you been with the woman when I joined you?” “Not more than a couple of minutes.” “What is your name?” “Lucy Sloan. I am employed by Mr. John Madden, sir, who lives in the big marble house on the other side of the avenue. I have been there five years, sir, ever since Amy was a baby. Oh, what shall I do to find her? The master’s heart will break unless I can find her.” The girl pointed to a palatial marble residence on the opposite side of Fifth Avenue, that of a millionaire banker and broker, whose operations in the stock market a dozen years before had given him not only vast wealth, but also a national reputation. He then had subsided, however, and during more recent years he had devoted only part of his time to business, though he still retained his interests in the firm of which he long had been the senior member, that of Madden, Mellen & Mack.