“_Possible suspects._ (1) Moss. Why did he leave in such a hurry? The fact of the murderer being on the spot last night, when he got that walking-stick, seems to rule Moss out. But not necessarily. He might easily have run down from London last night. There’s a lot to be inquired into here. (2) Grayson, the artist. Why did he leave in a hurry? He’s certainly got to be run to earth. (3) Proctor. Yes—Proctor puzzles me. Such a cool old chap! He would have known exactly where to land in that canoe—and, if so, he knew perfectly well that the boy would find it there in the morning. Also, he’s been in Switzerland. That stick again! And I thought he was never going to leave off examining that cigar band at the inquest. We must keep a sharp eye on Proctor. If he’s not simply a fool, he’s as wily as they make ’em.” When he had closed his notebook and put it in his pocket, the detective lighted his pipe and sat, smoking thoughtfully, looking out of the window. He realised that the case was all the more difficult because the few clues that he held, and the slight facts he had to go upon, might equally apply to any one of the three persons he had enumerated as being suspicious. And if, as it seemed, his work was to eliminate two of these persons, he was anxious to make no mistake. Colson was not the detective of fiction. He was simply a shrewd, careful man, keenly observant, with a police training. Had he been that brilliant genius which the writer of fiction is so fond of delineating, he would, after his manner, by this time have made some supernaturally clever deduction, which would have enabled him to spot the criminal at once, and to run him down unerringly, with the additional triumph attached to it that all his colleagues, and every other person concerned, had been absolutely wrong in their suspicions. He would, probably, have adopted extraordinary disguises, kept all his clues and methods to himself, and never have given a hint of them to his superior officers, and finally have achieved that superlative climax in which he would have exclaimed, “Alone I did it!” But Colson was what, in spite of the writers of fiction, is a useful personage in tracing crime—Colson was a policeman, and he knew the value of those often-derided police methods. He, for example, could sit now, calmly smoking his pipe, secure in the knowledge that every police station in the district was on the look-out for Grayson, the artist, that in a very short time Moss would probably be found—also by police methods—and that a little police machinery, which the superintendent was already putting in hand as a result of their brief conference after the inquest, would prevent Proctor from slipping away from the neighbourhood unobserved—if he had any such idea in his mind.