In the afternoon Nick, disguised as a negro porter, went to L Street. Chick and Palsy had been instructed in the rôles they were to play. The house described by Patsy was found, but the carpenters and painters were not there, although the scaffolding was still in place. As the day was Saturday, Nick found an explanation for the absence of the workmen. According to union rules, every Saturday afternoon is a holiday. The sidewalk had not been cleared and there were boxes, bricks, broken boards, and odds and ends lying about. Just beyond the entrance to the stairway, and near the edge of the sidewalk, was a large hair mattress, the ticking which covered it being torn in many places. Nick went up the stairs and stopped in front of a small, dingy office, presided over by a slatternly woman of middle age. "Is Misto Mannion stayin' heah?" he asked, with an engaging smile. "Room eighteen, this flo'." was the short answer. "Ah'm gretly ableeged, Mistis. Ah'll fine hit, mahse'f. Don' yo' stir you' bones on mah 'count." As the woman made no effort to move, but simply stared at him, the false negro's courtesy seemed not to have been required. Before the room, whose windows overlooked the back yard, Nick stopped, for inside a man was singing softly to himself. The voice was a light tenor and was pleasing to the ear. "The fellow is in happy spirits, apparently," thought the detective. "Hope I won't agitate him too much." He knocked gently and presently the door opened and a tall, rather handsome young man, with dark face, red, womanish lips, cold blue eyes set close together, and a low forehead confronted him. Women might be deceived in respect to his character. Men of sense would not be likely to trust him. He was dressed in the height of fashion and seemed, entirely at his ease. His eyes, in cool inquiry, sought the face of the black-faced caller, whose form trembled slightly. "Well," he said curtly, "what can I do for you?" "Ise--Ise de pusson yo' talked to tudder day down by de w'arf, sah," said Nick humbly. "Yo' gimme dat bank-bill fo' ter git changed, sah. Don' yo' 'member dat perceedin'?" "Yes." A change, swift as lightning, swept over Mannion's countenance. He was no longer cool and nonchalant, but keen, alert, on his guard. "What about it?" "Nuffin', sah, on'y I sho' don' desiah fo' ter git inter no trubble 'bout dat bill." "Get into trouble? How can you get into any trouble? The bill was all right, and, anyhow, you didn't change it. You gave it back to me." "Dat's truf, sah, but de coppers done foun' hit an' days er keepin' hit. Dat's wat eatin' mah heart out, sah. Wat do de coppers want wid dat bill? Lucy Miranda--dat's mah ole woman--she say dat de bill is a hoodoo, an' dat I gotter hab dat young man wat gib hit ter me go git it an' take de hoodoo off." Nick, looking at Mannion closely, thought he observed signs of perturbation. "Have you spoken to any one about our transaction the other day?"