As a matter of fact, the second examination of the house had not added to the great detective’s knowledge, although it had confirmed him in certain beliefs. “This house was entered by professional burglars,” he said to himself. “Whether they entered simply for the purpose of burglary, and, finding the case, carried it away with them, or whether they were employed to enter this house to obtain that case, and took the plate and jewelry because they could do so easily, are questions which I cannot determine on this showing.” He was in Mrs. Herron’s room when he said this to himself, and, thinking it over, he went to the front window and looked out. On the opposite side of the street, seated on the lower step of a house immediately opposite, was Patsy, talking to an ill-favored specimen of a man similarly seated. A single glance assured Nick that Patsy was not idling his time, but was there for a purpose. Whether he was watching for him or not, Nick could not tell, but he drew the curtains aside and placed himself close to the window. Patsy saw him at once and made a series of rapid signals to Nick. They meant to Nick that Patsy had hit upon a man important in their search, that he wanted the man followed while he, Patsy, could make a change in his appearance. Telling Mr. Herron that he had no more business in the house and would at once begin the search, Nick descended the stairs, and, opening the front door, stood a moment within the vestibule, where he signaled to Patsy with his hands that he had understood him. Patsy immediately got up, and, after a word or two with the fellow beside him, walked off in the direction of the west without looking behind. The fellow slouched down the street to the east and Nick went after him at a safe distance, taking the precaution to cross the street, so as to be on the same side with him. Nick did not know the purpose of the shadow, but he had confidence enough in Patsy to take up the lines suggested blindly. The man led Nick to Third Avenue, where he turned to the right, or, toward Thirty-fourth Street. Here Nick made a mark in red chalk on the corner, which should indicate to Patsy the direction in which they turned. At the corner of Thirty-fourth Street, the fellow crossed to Third Avenue and stationed himself against a pillar of the elevated railroad, from which point he could keep an eye on each of the four corners. He watched each of these corners as if he were waiting for some one. Nick put himself out of sight, after he had made a mark on the pavement with red chalk, that would tell Patsy, on his return, that he was there, and waited. But he did not wait long, for Patsy, in an excellent make-up of an east-side tough, slouched up. Seeing the mark on the pavement, he looked about, first to locate the man followed, and then for his chief. Nick beckoned to him from a doorway, and Patsy went to him. “What is it, Patsy?” asked Nick.