"Ah, the constable, eh? You shall tell me, please, Mr. Narkom, is this the constable who was at the one end of the arch while the keeper was chasing the man in at the other? Ah, it is, eh? Well—er—shall not we see the keeper, too? I do not find him about and I should much like to speak with him. Where is he?"

"Who—the keeper?" said Narkom. "Blest if I know. Is he about, my lads?"

"No, sir. Ain't been about—has he, Petrie?—for the Lord knows how long. Never thought of the beggar until this moment, sir."

"Nor did I," said Narkom. "Come to think of it, I haven't seen the fellow since we came to the 'Y' of the road and found those footprints leading here. No doubt he has gone back to his shelter on the Common and—— Monsieur! Why are you smiling? Good God! you— I—— Monsieur, shall I send my men for the fellow? Do you want to see him?"

"Yes, Monsieur Narkom, I want to see him very, very much indeed—if you can find him! But you can't, monsieur; and I fear me that you never will. What you will find, however, if you will send your men to the shelter of which you speak will be the real keeper, either dead or stunned or gagged, and his coat and hat and badge removed from his body by the man who personated him."

"Good heavens above, man, you don't mean to say——"

"That you had the real criminal in your hands and let him go, that you talked with him, walked with him, were taken in by him, and that he told you no lie when he said the assassin really did run into the arch," replied Cleek quietly. "It is the old old trick of that fellow who was called the 'Vanishing Cracksman,' my friend: to knock down the fellow who first gives the alarm, rip off his clothing, and then to lead the hue and cry until there's a chance to steal away unobserved. Send your men to the keeper's shelter and see if I have guessed the truth of that little riddle or not. I'll lay you a sovereign, my friend, that your man has slipped the leash, and it will be but a fluke of fate if you ever lay hands on him again."

In a sort of panic Narkom turned to his men and sent them flying from the house to investigate this startling assertion; and, turning as they went, Cleek walked into the room where that awful dead figure hung. He had taken but one step across the threshold, however, when he stopped suddenly and began to sniff the air—less to the surprise of Narkom, who had often seen him do this sort of thing before, than to Constable Mellish, who stood looking at him in open-mouthed amazement.

"Good lud, man— I should say, monsieur," exclaimed the superintendent agitatedly, "after what you have just hinted, my head is in a whirl and I am prepared for almost anything; but surely you cannot find anything suspicious in the mere atmosphere of the place?"

"No; nothing but what you yourself must have observed. There is a distinct odour of violets in the room; so that unless that unhappy man yonder was of the kind that scents itself, we may set it down that a woman has been in here."