There was a pause while the chief and the remainder of the party absorbed this.
"Dead," exclaimed the chief. "How?"
"Suicide by poison," was the brief response. "Anyway, I had established the ownership of the dagger. I also learned that Hassan had been in Boston only five days at the time the body was found. The girl had been dead for a week or ten days-possibly ten days. Therefore, Hassan did not kill Miss Gorham. That was conclusive.
"Then came the question of how the dagger passed out of his possession. Obviously it was not a gift. Stolen? Probably. When? Mr. Hassan showed in a way that he had not been in Boston for two years. But burglars operate all over the country. Therefore, burglars. It is perfectly possible that the dagger was stolen some time in Washington by 'Reddy' Blake and his gang, and for some reason they kept it instead of selling it. No man, not even a 'fence,' would have tried to dispose of a four-carat diamond. In the second place, Mr. Hassan would not have dared to report the loss of the dagger to the police. Blake, of course, could not know this. He kept the weapon. The safest place for it was on his person."
The Thinking Machine lay back in his chair, squinting at the ceiling, while his listeners leaned forward eagerly. The chief was fascinated, amazed by the strange story. The scientist resumed:
"It was stated in the hearing of Mr. Hassan and also published that the dagger was in the possession of Medical Examiner Loyd. It is easy to see how employees of this man burglarized Loyd's home and recovered the weapon. Its possession meant life to Hassan. Immediately after this burglary he returned to Washington. There he committed suicide, probably by order of his superiors. I had wired the facts, not intending to cause his death, of course, but to have the dagger produced here when necessary. That disposes, I think, of the ownership of the weapon, and places it in the hands of 'Reddy' Blake or his pals."
The Thinking Machine turned suddenly on Clements.
"As collector for Henry Holmes & Co. you know Cambridge well, I should imagine. You have opportunities, which fall to few men-legitimately-to know where rich hauls may be made. You were also in a position to know practically every vacant house in Cambridge. Knowing this you might know, too, the best vacant house for a rendezvous for thieves. In passing, you might have learned that the house rented by Mr. Wilkes had not been occupied. It is perfectly possible that you did not even know the house had been rented until the bill for rent was placed in your hands. These are possibilities; now here are facts.
"You went to that house to collect rent. The front door was locked and the shutters up. In the natural course of events you would have satisfied yourself that it was unoccupied. You might have shouted to attract someone's attention, but in the ordinary course of events you would not have gone upstairs to look further, unless you had asked something. You found something in a back room and probably behind a door that was closed. You broke open that door. Why did you go to that room? Why did you break down that door?
"Let's see. Suppose for a moment that you were one of the most valued members of a gang of burglars-valued because you appear the gentleman and can go places and learn things without attracting attention. Suppose this house was a hiding place for stolen goods. Suppose the girl, answering Mr. Wilkes's advertisement for a companion, should have gone to that house and found it locked. It is not improbable that she should have gone around the house, believing it to be occupied, to find someone.
"Suppose she had come upon a party of thieves. It would have been a natural consequence for them to fear a spy and attempt to get rid of her.
"What more possible than that they should have locked her up? She was at least four hundred feet from the nearest house, and forty, fifty or sixty feet from the street and behind thick walls. Her screams would not have been heard.
"There we have the girl a prisoner in the hands of the men who had the golden dagger. The murder may have followed at any time. It happened but a few days ago. Meanwhile the burglars had taken from their loot a bed and its furnishings, providing a place for the girl to sleep. You, Mr. Clements, knew that the girl had been a prisoner upstairs. That is why you went to that room. I will not say that you knew of the murder at that time. You discovered that. You were frightened at this hideous ending of an affair in which you had been interested. Perhaps you were a little angry, too. It may have been that the burglars had taken away the stolen stuff, sold it and left you out in the division. Is that right?"
Clements stared at him with glassy eyes, then suddenly leaned forward with his head in his hands, and sobbed bitterly. It was practically a confession.
"How did it come that you considered burglars in the first place?" asked the chief.
"I made two examinations of the house. The first was not thorough. I examined the faucets to see if the water was on, and if there was a possible trace of blood on them anywhere. It was not impossible that the murderer of Miss Gorham got blood on his hands and left a thumb or finger print when he washed it off. I found none. He was careful.
"On the second examination I looked particularly for a trace of burglars in the cellar. There I found, freshly pressed down in the soft soil, the imprint of what must have been a carved piano leg and beside it a large imprint indicating that a grand piano had been leaned against the wall. People don't keep pianos in the cellar. Therefore, if one were there, it was hidden. Naturally burglars. The bed was not handsome, but was of mahogany. Nobody moving out would leave a mahogany bed. Still burglars. There is no path leading from the back of the house to the back fence. Yet there is a straight line across the grass to a certain panel in that fence where people have walked frequently. That panel of the fence fell out when I shook it; there is no gate. Burglars, even at night, would not move their loot in at the front; it would be comparatively easy to bring in large objects, such as a piano, through the alley, tearing down a fence panel and then to the house. Therefore burglars.
"Now, burglars do not steal pianos and mahogany beds in a wagon from a house that is occupied. The police informed me that burglars-'Reddy' Blake, among them-had been robbing an unoccupied furnished house. They could have stolen a piano or anything else. Therefore the chain is complete."
"Admitting that is all true," interrupted the chief, "how did you explain the fact that the man who killed Miss Gorham left the dagger? If he had been a burglar, as you say, wouldn't he have been the last man to leave a thing of that value?"
"All men are fools when they kill people," said The Thinking Machine. "They are frightened, half-witted, and do all kinds of inexplicable things. Suppose there had been a sudden violent noise in the house, made by one of his pals just at the moment the girl fell backward, covering the knife with her body. The murderer might have run, leaving it where it was. I don't state this as a fact, but as a strong probability. He might have intended to return for the knife, but if he had meanwhile been arrested, as Blake and Johnson were, this would have been impossible. I think that is all."
"Why is it that Mr. Wilkes did not see the stolen goods when he went to look at the house?" asked the chief.
"Because they were in the cellar. You didn't go into the cellar, did you, Mr. Wilkes?"
"No; oh, no," Wilkes replied.
"And remember, the girl wasn't in the house then," The Thinking Machine added. "She went to answer the advertisement which appeared after Mr. Wilkes had rented the house."
Then Hutchinson Hatch, who had been an interested listener, had a question.
"Why did you ask Mr. Wilkes if he had ever seen the knife or had given an order for a blade for it?"
"The blade in the dagger was of American make," replied the scientist. "The original had been broken. Peculiarly enough the new blade was made by the cutlery company which Mr. Wilkes represents. It was not impossible, therefore, that this dagger had been in his possession."
There was a long silence. The chief and Detective Fahey removed their half-chewed cigars and looked inquiringly at each other. Fahey shook his head-he had no questions. At last the chief turned to The Thinking Machine:
"If, as you say, Blake or Johnson killed Miss Gorham, how can we prove it? This is not proof-it is theory."
"Simply enough. Do the men occupy the same cell in Charlestown?"
"I hardly think so. Members of a gang that way are rarely kept in the same cell."
"In that case," said The Thinking Machine, "let the warden go to each man and tell him that the other has turned state's evidence, accusing his pal of the murder."
Johnson confessed.
_______________________.
PROBLEM OF THE KNOTTED CORD.
With the brilliant glare of the noonday sun shining full into his upturned eyes, a venerable man sat beside an open window. The gray-crowned head was a noble one, but strength and rugged manhood was gone; there was only the weakness of years and disaster, illumined and softened by a smile-the appealing, pathetic smile of helplessness. The window framed a vista of green landscape, broken by a dimpled splotch of blue where the sea ran in and lapped the shore, and, far away, a village sprinkled on the hills. But he looked upon it all with sightless eyes-eyes which turned instinctively toward the light as the blind ever seek a ray through their enshrouding gloom. A grateful tang of salt air drifted in, and he breathed deeply of its fragrance.
For a long time he sat thus, silently, then from a distant room came the trill of a song. His smile grew into an expression of infinite tenderness as he listened, and then the closing of a door broke the melody. He sat expectantly for a minute or so, and gradually his mind wandered back into the dreamy thoughtfulness which the voice had interrupted. After awhile he heard a light step in the hall, and then some other sound which he could not interpret. The steps approached the door of the room where he sat, and paused.
"Is that you, deary?" he asked gently.
There was no response, and he turned his sightless eyes expectantly toward the entrance.
"What is it, Mildred?" he inquired.
Again he heard the peculiar sound to which he had been unable to attach a meaning, but still there was no answer.
"Mildred!" he called sharply. He turned quickly in his chair, with a vague uneasiness in his manner, and gripped the arms as if to rise. "Mildred!" he repeated. "Why don't you answer me?"
Suddenly there came an answer-a heart-racking, terrifying answer-shriek after shriek of agony, terror, helplessness. It was here, in this very room in which he stood, but the impenetrable pall of blindness veiled it all. There was a shuffling as of feet for an instant, a gurgling, despairing cry, then the old man tottered forward toward the door.
"Mildred, Mildred, Mildred!" he called despairingly. "What is it, child!"
There was a sound as of a soft body falling, then came utter silence. With straining heart and groping hands the old man kept on blindly seeking. Again he caught the meaningless sound, which he had heard before. One outstretched hand brushed against something which was instantly removed beyond reach. Intuitively he knew that something-somebody-menaced him, that Mildred his granddaughter was now or had been in peril-perhaps it was worse. There was some quick movement to his right, and the old man stretched out his quivering hands straight before him with a pitiful, helpless gesture.
"I am blind!" he said simply.
For a moment he stood there, with hands still outstretched, waiting. For what? He didn't know. At last from the hall outside came a sliding, whispering sound, and the front door closed noiselessly. Instantly he started in that direction. Despite his blindness, he knew his way here in the little house where he had lived for years alone with his granddaughter.
In the hall another thought came to him. Whoever-whatever-it was, had come and gone. And Mildred? He turned and started back toward the room he had just left. One aged hand slipped along the wall to the door frame, and he turned in. For an instant he listened. He heard nothing.
"Mildred?" he called. "My God, child! where are you? What has happened?"