"Yes， sir， I think likely， sir，" murmured Johann. "But if the murderer could get into the house， how could he get into the apartment？"

　　"There must have been a third key of which you knew nothing，" answered Horn， turning to Muller again. "It's stranger still how Fellner could have been shot， for the window-shutters were fastened and quite uninjured， and both doors were locked on the inside."

　　As he said these words， Horn looked sharply at his subordinate； but Muller's calm face did not give the slightest clue to his thoughts. The experienced police commissioner was pleased and yet slightly angered at this behaviour on the part of the detective. He knew that it was quite possible that Muller had already formed a clear opinion about the case， and that he was merely keeping it to himself. And yet he was glad to see that the little detective had apparently learned a lesson from his recent mistake concerning the death of Mrs. Kniepp - that he had somewhat lost confidence in his hitherto unerring instinct， and did not care to express any opinion until he had studied the matter a little closer. The commissioner was just a little bit vain， and just a little bit jealous of this humble detective's fame.

　　Muller shrugged his shoulders at the remark of his superior， and the two men stood silent， thinking over the case， as the Chief of Police appeared， accompanied by the doctor， a clerk， and two hospital attendants. The chief commissioner received the report of what had been discovered， while the corpse was laid on a bier to be taken to the hospital.

　　Muller handed the commissioner his hat and cane and helped him into his overcoat. Horn noticed that the detective himself was making no preparations to go out. "Aren't you coming with us？" he asked， astonished.

　　"I hope the gentlemen will allow me to remain here for a little while，" answered Muller modestly.

　　"But you know that we will have to close the apartment officially，" said Horn， his voice sharpening in his surprise and displeasure.

　　"I do not need to be in these rooms any longer."

　　"Don't let them disturb you， my dear Muller； we will allow your keenness all possible leeway here." The Head of Police spoke with calm politeness， but Muller started and shivered. The emphasis on the "here" showed him that even the head of the department had been incensed at his suggestion that the beautiful Mrs. Kniepp had died of her own free will. It had been his assertion of this which， coming to the ears of the bereaved husband， had enraged and embittered him， and had turned the power of his influence with the high authorities against the detective. Muller knew how greatly he had fallen from favour in the Police Department， and the words of his respected superior showed him that he was still in disgrace.

　　But the strange， quiet smile was still on his lips as， with his usual humble deference， he accompanied the others to the sidewalk. Before the commissioners left the house， the Chief commanded Johann to answer carefully any questions Muller might put to him.

　　"He'll find something， you may be sure，" said Horn， as they drove off in the cab.

　　"Let him that's his business. He is officially bound to see more than the rest of us，" smiled the older official good-naturedly. "But in spite of it， he'll never get any further than the vestibule； he'll be making bows to us to the end of his days."

　　"You think so？ I've wondered at the man. I know his fame in the capital， indeed， in police circles all over Austria and Germany. It seems hard on him to be transferred to this small town， now that he is growing old. I've wondered why he hasn't done more for himself， with his gifts."

　　"He never will，" replied the Chief. "He may win more fame - he may still go on winning triumphs， but he will go on in a circle； he'll never forge ahead as his capabilities deserve. Muller's peculiarity is that his genius - for the man has undeniable genius - will always make concessions to his heart just at the moment when he is about to do something great - and his triumph is lost."

　　Horn looked up at his superior， whom， in spite of his good nature， he knew to be a sharp， keen， capable police official. "I forgot you have known Muller longer than the rest of us，" he said. "What was that you said about his heart？"

　　"I said that it is one of those inconvenient hearts that will always make itself noticeable at the wrong time. Muller's heart has played several tricks on the police department， which has， at other times， profited so well by his genius. He is a strange mixture. While he is on the trail of the criminal he is like the bloodhound. He does not seem to know fatigue nor hunger； his whole being is absorbed by the excitement of the chase. He has done many a brilliant service to the cause of justice， he has discovered the guilt， or the innocence， of many in cases where the official department was as blind as Justice is proverbially supposed to be. Joseph Muller has become the idol of all who are engaged in this weary business of hunting down wrong and punishing crime. He is without a peer in his profession. But he has also become the idol of some of the criminals. For if he discovers （as sometimes happens） that the criminal is a good sort after all， he is just as likely to warn his prey， once he has all proofs of the guilt and a conviction is certain. Possibly this is his way of taking the sting from his irresistible impulse to ferret out hidden mysteries. But it is rather inconvenient， and he has hurt himself by it - hurt himself badly. They were tired of his peculiarities at the capital， and wanted to make his years an excuse to discharge him. I happened to get wind of it， and it was my weakness for him that saved him."

　　"Yes， you brought him here when they transferred you to this town， I remember now."

　　"I'm afraid it wasn't such a good thing for him， after all. Nothing ever happens here， and a gift like Muller's needs occupation to keep it fresh. I'm afraid his talents will dull and wither here. The man has grown perceptibly older in this inaction. His mind is like a high-bred horse that needs exercise to keep it in good condition."

　　"He hasn't grown rich at his work， either，" said Horn.