It was no part of the detective’s plan, however, to reveal his knowledge of the deception. He wished to give the masquerader as much rope as he could, in order to find out just what Gordon was trying to do. Moreover, he was curious to visit Gillespie’s house and find out how Green Eye had succeeded in making himself at home there. Gillespie might have been overpowered and stowed away somewhere, or even murdered—though that was unlikely, unless the crime had been committed owing to an accident or miscalculation on Gordon’s part. When the detective reached Gillespie’s house on Fifth Avenue, he found the situation just as Gordon had described it. An aged butler answered the bell, and, save for him, the big house seemed deserted. Nick was about to question the old man in a roundabout way in order to discover, if possible, whether there had been anything which might seem suspicious or not. Before he could do so, however, the butler offered a couple of letters on a salver. Nick took them after a second’s hesitation, studying the butler’s face as he did so. From the man’s squint and the lines about the eyes, he saw that the butler was nearsighted. Probably he had been in the family for a long time, but this defect in his eyesight explained his failure to detect the deception. But where was the real Chester J. Gillespie, whose second double was now entering his house, and calmly inspecting his letters? Gordon had given Nick certain necessary particulars concerning the arrangement of the house, and, thanks to these, the detective mounted the stairs with the utmost assurance, leaving the nearsighted old butler bowing in the lower hall. He found his way to Gillespie’s private room easily enough, the letters still in his hand. After looking about him curiously, and noting the certain evidences of recent occupancy, he sat down and glanced mechanically at the letters. One of them obviously was a business communication, but the other was not. The envelope was unusually large, and of the finest texture. As for the writing, it was big, heavy, and sprawling. In the lower left-hand corner were the words, “Important—please forward,” and they were heavily underscored. All is fair in love and war, they say, and if that is so, all is fair in detection as well, especially when the detective is trying to safeguard the man whose identity he has temporarily appropriated. Under the circumstances, therefore, Nick felt justified in opening any of Gillespie’s correspondence that seemed to promise a solution of the mystery, just as he would have ransacked the house for a similar clew. There might be nothing in it, of course, but this letter appeared to be somewhat out of the ordinary, and might be valuable. Consequently, after a little hesitation, Nick ripped the envelope open without the slightest attempt at concealment, and drew the inclosure out. Soon he was very glad that he had done so, for the letter read as follows: