“I’d like to be going with you,” said Chick, with a shade of envy in his voice. “Those big balls at the Hotel Supremacy are always worth seeing. I dare say I could have got an invitation.” “I am going on business, Chick,” returned his chief coldly. “I know that. Still, some business is pleasanter than others,” persisted Chick. “You are going to do the tango, I suppose?” “I shall not dance,” was the answer. “I intend to go up in the balcony to look on. I’ll get into a private box if I can.” The telephone bell rang, and Chick answered. Then he turned to Nick. “It’s Corliston, the costumer.” “Find out what he’s after. I suppose he wants to apologize for sending me the wrong costume.” That was exactly what Corliston did want. There had been a Spanish officer and a Mexican both ordered, and through an error on the part of some of his men, the Spanish officer had gone to somebody else. He hoped Mr. Carter would not be much inconvenienced. If there was anything he could do, et cetera, et cetera. “Tell him it is all right,” directed Nick shortly. He put a light overcoat over his Mexican rig, and went down to the taxi waiting for him at the front door. There had been some counterfeits of big bills worrying the treasury department of late, and Nick Carter had been asked to help in gathering in the persons who were making and “shoving” the bad bills. Information had reached Nick that some of the guests at the mask ball at the big hotel might be the men he was after. The hint had come to him anonymously, and he did not like it. Ordinarily he would have hesitated about giving such a message serious attention. He had the contempt of all decent people for unsigned communications of this kind. But he surmised, from the general appearance of the letter, as well as its wording, that it had been written by somebody who had been in the gang, and had left it with a feeling of being illtreated. So he felt that he could not afford to throw it aside without investigation. When he reached the hotel, and, with his heavy, bullion-trimmed sombrero in his hand, went up in the elevator to the ballroom floor, he found that the gathering was likely to be a large and gay one. One of the features of the main ballroom of the Hotel Supremacy is the ring of private boxes overlooking the large floor. The boxes are immediately below the open balcony, so that they are shadowed and give plenty of privacy to guests who may desire to see without being observed. Nick was standing just inside the ballroom, looking over the floor through the eyeholes of his black mask, and trying to determine whether any of the disguised men promenading or dancing were likely to be his counterfeiters, when an attendant touched him on the elbow, and whispered: “This way, sir!” It was one of the rules of Nick Carter to follow any lead that might be thrown out to him, just to see where it would take him. Also, he never permitted himself to show surprise.