The doctor left the house. Muller smiled bitterly as he closed the door behind him, and murmured to himself: "Indeed, I do not forget it, and that is why I shall take this matter into my own hands. But the Kniepp case is not closed yet, by any means."

When he returned to the study he saw Johann sitting quietly in a corner, shaking his head, as if trying to understand it all. Horn was bending over a sheet of writing paper which lay before the dead man. Fellner must have been busy at his desk when the bullet penetrated his heart.

His hand in dying had let fall the pen, which had drawn a long black mark across the bottom of the sheet. One page of the paper was covered with a small, delicate handwriting.

Horn called up the detective, and together they read the following words:

"Dear Friend:--

"He challenged me--pistols--it means life or death. My enemy is very bitter. But I am not ready to die yet. And as I know that I would be the one to fall, I have refused the duel. That will help me little, for his revenge will know how to find me. I dare not be a moment without a weapon now--his threats on my refusal let me fear the worst. I have an uncanny presentiment of evil. I shall leave here to-morrow. With the excuse of having some pressing family affair to attend to, I have secured several days' leave. Of course I do not intend to return. I am hoping that you will come here and break up my establishment in my stead. I will tell you everything else when I see you. I am in a hurry now, for there is a good deal of packing to do. If anything should happen to me, you will know who it is who is responsible for my death.

His name is--"

Here the letter came to an abrupt close.

Muller and Horn looked at each other in silence, then they turned their eyes again toward the dead man.

"He was a coward," said the detective coldly, and turned away. Horn repeated mechanically, "A coward!" and his eyes also looked down with a changed expression upon the handsome, soft-featured face, framed in curly blond hair, that lay so silent against the chair-back. Many women had loved this dead man, and many men had been fond of him, for they had believed him capable and manly.

The commissioner and Muller continued their researches in silence and with less interest than before. They found a heap of loose ashes in the bedroom stove. Letters and other trifles had been burned there. Muller raked out the heap very carefully, but the writing on the few pieces of paper still left whole was quite illegible. There were several envelopes in the waste-basket, but all of them were dated several months back.

There was nothing that could give the slightest clue.

The letter written by the murdered man was sufficient proof that his death had been an act of vengeance. But who was it who had carried out this secret, terrible deed? The victim had not been allowed the time to write down the name of his murderer.

Horn took the letter into his keeping. Then he left the room, followed by Muller and the valet, to look about the rest of the house as far as possible. This was not very far, for the second story was closed off by a tall iron grating.

"Is the house door locked during the daytime?" asked Horn of the servant.

"The front door is, but the side door into the garden is usually open."

"Has it ever happened that any one got into the house from this side door without your knowing it?"

"No, sir. The garden has a high wall around it. And there is extra protection on the side toward the Promenade."

"But there's a little gate there?"

"Yes, sir."

"Is that usually closed?"

"We never use the key for that, sir. It has a trick lock that you can't open unless you know how."

"You said you went to the theatre yesterday evening. Did your master give you permission to go?"

"Yes, sir. It's about a year now that he gave me money for a theatre ticket every Sat.u.r.day evening. He was very kind."

"Did you come into the house last night by the front door, or through the garden?"

"Through the garden, sir. I walked down the Promenade from the theatre."

"And you didn't notice anything--you saw no traces of footsteps?"

"No, sir. I didn't notice anything unusual. We shut the side door, the garden door, every evening, also. It was closed yesterday and I found the key--we've only got one key to the garden door--in the same place where I was told to hide it when I went out in the evening."

"What place was that?"

"In one of the pails by the well."

"You say you were told to hide it there?"

"Yes, sir; the Professor told me. He'd go out in the evening sometimes, too, I suppose, and he wanted to be able to come in that way if necessary."

"And no one else knew where the key was hidden?"

"No one else, sir. It's nearly a year now that we've been alone in the house. Who else should know of it?"

"When you looked through the keyhole last night, are you sure that the Professor was still alive?"

"Why, yes, sir; of course I couldn't say so surely. I thought he was reading or writing, but oh, dear Lord! there he was this morning, nearly twelve hours later, in just the same position." Johann shivered at the thought that he might have seen his master sitting at his desk, already a corpse.

"He must have been dead when you came home. Don't you think the sound of that shot would have wakened you?"

"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. .h.i.therto 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 a.s.sertion 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.