“It has helped me to know where Professor Tolo has gone, or will go, I think,” he answered. “I’m going to see if I can find him. You stay here, however. I have a feeling that the mystery of Andrew Anderton’s death may be solved in or near his own home.” “I don’t see, exactly,” replied Patsy. “But if you think Tolo had something to do with it, why don’t you nab him, and prove it on him afterward. That’s the way the police do, generally.” “It’s a good way, too, in some cases, Patsy. But I want to get more than one man now. Besides, I don’t believe Professor Tolo actually committed this murder.” “But he was behind it.” “Very likely. But what I want is the rascal who killed Mr. Anderton. If once I were to show my hand by having this Japanese professor arrested, the Chinaman, or whoever it was that drove the crossed needles into his heart would take fright.” “Either that or they would try to get you,” declared Patsy doggedly. Nick Carter shrugged his shoulders. He believed the Yellow Tong was on his track now. That was why he wanted to strike at several of the members at once, instead of merely picking off one man--even so important a one as this Japanese professor seemed to be. “Never mind about talking. Stay in this room till I come back. But--here is something else. I wish you would sit by that window, behind the lace curtains, and partly behind the dark ones that are drawn over the window at night.” “I see,” threw in Patsy. “There are two sets of curtains, one inside the other. You want me to keep out of sight of anybody outside. But who is there to see me? At the back is a big, vacant lot, and we are too high for any one in the yard to look in.” “Quite so, Patsy. I am aware that nobody in this yard could see you at the window, even if there were no curtains. But it is the next yard I want you to watch. The yard on your right as you stand at the window.” “Oho!” exclaimed Patsy, with a low whistle. “I’m on. That’s where the chinks went when I missed them last night. They didn’t come in here, but they sneaked into the next house.” “Probably.” “Yes, and I bet they slipped down into the basement. There is a gate in the iron railings. I see just what they did. They went through that gate and were out of sight in the kitchen while I was watching this house. Gee! This is going to be dead easy!” “I don’t know about that. But I hope we are getting a net around the rascals. I don’t think I shall be away more than an hour. I’m going to see Mr. Bentham, over in Brooklyn. If I don’t find anything there, I’ll come back as fast as Danny Maloney can bring me. If there is anything to keep me, I’ll telephone you right in this room from Mr. Bentham’s house. Get all that?” “Every word. So long!” Patsy moved over to the window and ensconced himself behind the curtain, in accordance with his instructions, and Nick Carter drove away to Brooklyn. CHAPTER XI. THE LETTER.