Dave nodded. "Yes; watchin' the guests, to see they don't carry off each other. It is the new ones that puzzle us for a while," he added. "Now, there is a lady acting very mysteriously over there." His eye swept over the room and then visited, in that casual way it had, some one in the corner across the room. "I don't just seem to make her out. She looks all right--but--?" Keith followed the glance, and the blood rushed to his face and then surged back again to his heart, for there, standing against the wall, was the young girl whom he had spoken to on the street a few evenings before, who had given him so merited a rebuff. She was a patrician-looking creature and was standing quite alone, observing the scene with keen interest. Her girlish figure was slim; her eyes, under straight dark brows, were beautiful; and her mouth was almost perfect. Her fresh face expressed unfeigned interest, and though generally grave as she glanced about her, she smiled at times, evidently at her own thoughts. "I don't just make her out," repeated Mr. Dennison, softly. "I never saw her before, as I remember, and yet--!" He looked at her again. "Why, I do not see that she is acting at all mysteriously," said Keith. "I think she is a music-teacher. She is about the prettiest girl in the room. She may be a stranger, like myself, as no one is talking to her." "Don't no stranger git in here," said Mr. Dennison, decisively. "You see how different she is from the others. Most of them don't think about anything but themselves. She ain't thinkin' about herself at all; she is watchin' others. She may be a reporter--she appears mighty interested in clothes." "A reporter!" The surprise in Keith's tone amused his old pupil. "Yes, a sassiety reporter. They have curious ways here. Why, they pay money to git themselves in the paper." Just then so black a look came into his face for a second that Keith turned and followed his glance. It rested on Ferdy Wickersham, who was passing at a little distance, with Mrs. Wentworth on his arm. "There's one I am watchin' on my own account," said the detective. "I'm comin' up with him, and some day I'm goin' to light on him." His eye gave a flash and then became as calm and cold as usual. Presently he spoke again: "I don't forgit nothin'--'pears like I can't do it." His voice had a new subtone in it, which somehow sent Keith's memory back to the past. "I don't forgit a kindness, anyway," he said, laying his hand for a second on Keith's arm. "Well, see you later, sir." He moved slowly on. Keith was glad that patient enemy was not following him.