"Well, we'll meet you officers and the Collector on board the steamer Campania, of the Cunard line, in one hour, when she reaches her pier from Quarantine. If we don't show up more smugglers than you do, we'll give up this assignment." "I'll go you!" eagerly exclaimed the jealous inspector. "And I'll be there to see that you get fair play," grimly said the Collector. The Bradys silently bowed and withdrew. When they reached the street, Old King Brady laughed and said: "They're all jealous of us. But we'll show them a trick or two, Harry." "They'll be a surprised lot," laughed the boy. "We have them beaten already." They headed for the jewelry district and called upon several of the most prominent importers and lapidaries, from whom they gained some very valuable information. The last importer they spoke to said: "Paul La Croix, a French-Canadian, was just in here with his daughter, trying to sell us some smuggled diamonds. See--there he goes now." He pointed out the window at a tall, thin, stylishly-clad man of forty in light trousers, a black frock coat and high hat. The detectives observed that he now did not have his daughter with him. From where they were, they could see that La Croix had a thin, sallow face, a long, sharp nose and a closely-trimmed dark moustache. He turned into Broadway and disappeared in the crowd. "Who is he?" asked Old King Brady, of the dealer in precious stones. "A mystery. No one knows. He makes many trips between New York and Havre to smuggle diamonds which he sells here. Every jeweler in the Lane knows him. Some deal with him." "Where does he live?" "At the Fifth Avenue Hotel." "Thank you." And a moment later the detectives were gone. Reaching Broadway they hurried ahead intending to find La Croix and arrest him with contraband diamonds in his possession. But the man disappeared and they found no trace of him. The Bradys gave up the hunt, temporarily, for they were determined to find the man again. They crossed the city, going to the west side. People who saw the pair paid no heed to them now, for they had made some changes in their apparel, in a sheltering doorway, and by turning their coats inside out, pocketing their uniform hats and putting on soft felt hats, they transformed their appearance. They now looked like ordinary citizens. Each one adjusted a false moustache and a wig to hide his identity. They had their clothing so made that they could change to several characters with but little trouble. This fact was well known to most of the crooks at large, and they feared the Bradys more than any other detectives on the force. Although they bore the same name, there was no relationship between them, for Harry was merely an apt pupil the old detective had chanced to meet, and was educating in his profession. As a team, they made themselves famous. When they drew near the Cunard steamship dock, Old King Brady carried his handkerchief in his hand as a signal.