It would have been a nervous situation for most men. Wentworth was tense and alert as he worked over the insensible man, and he was very, very tired. But he was not nervous. Probably some day he would face the approach of his own death with nerves that left him the benefit of calm thought.
More minutes passed, fifteen of them, and nothing further happened. Silence dwelt in the house of the boarded windows. Even the street noises were cut off from the little laboratory at the back of the house. Then Wentworth felt the slightest of quivers in the body of Selwyn. He continued his efforts without pause and felt a very gentle, but natural breath. He reached for the pulse and could detect a faint heart beat. Still he continued to work. He knew that it was like cranking a car when the self starter fails. Sometimes the engine turns over a few times and stops again.
Soon the breathing became more certain, the heart beat more distinct. At last he stopped his work and selected a clean beaker from a laboratory table. Into it he poured some brandy from his flask and diluted it with water from a faucet. He lifted Selwyn's head and poured a little of the weak stimulant into his mouth. In ten minutes Selwyn, his head resting on his folded coat, was able to talk in a weak voice. Naturally he was bewildered. He had, he said, been dreaming, having a horrible nightmare.
Wentworth soothed him as if he were a small child and gradually Selwyn's mind cleared. Out of a condition very similar to death, if not actually death itself, he had come back to the so-called realities of life, and his vigorous body began to pick up its old strength more rapidly than might have been expected.
His first words were for Dorothy. "Where is Dot?" he asked. "Is she all right?"
"She is safe and sound," Wentworth assured him.
"Oh! Then I guess everything will come out O.K."
Wentworth explained a little of the situation, refraining, at first, from putting searching questions, although he was very much puzzled as to why anybody should wish to kill this young man.
"Yes, I knew about you, Mr. Wentworth," Selwyn said. "Dot told me that she was going to ask you to help us."
Very slowly and gently Wentworth drew some of his story from him. Selwyn had been awakened before dawn by a man who claimed to be a doctor and who said that Dorothy had been hurt in an accident and was calling for him. He was so upset and frightened about Dorothy that he gave scant thought to the strangeness of entering the doctor's house through a back yard.
Once inside the house, the doctor, a pistol in one hand and a flashlight in the other, had conducted him upstairs to the laboratory and there bound and gagged him.
"But where did the blood on your sheets come from?" Wentworth asked.
Selwyn smiled weakly. "When the doctor awakened me I thought he was a policeman — and I hit him on the nose before he had time to explain who he was."
"And I thought it was your own life's blood," commented Wentworth dryly.
"I lay here for hours," Selwyn continued, "and then he put me in that horrible glass box."
The exertion of talking or the memory of the frightful moments of suffocation, before consciousness lapsed, turned the young man weak and faint. He became violently ill.
Wentworth gently held his head. Always his hand hovered near the pistol upon the floor, while his eyes darted continuously to the door. At any moment death might stalk through that door, and he had to be ready for instant action.
"But why did he want to kill me?" Selwyn asked faintly as his stomach settled and he felt a little better.
Wentworth looked closely at him. "Do you mean to tell me that you do not know?" he asked.
Selwyn shook his head.
"Do you know who took the diamonds away from you?"
Selwyn nodded. "Of course! It was my boss. Then he denied it and telephoned for the police, and I had to run. I had no chance."
"No," said Wentworth, "you are wrong. The man who took the diamonds from you is the man who just tried to murder you."
Selwyn looked his unbelief. He shook his head. "Couldn't be!" he protested "He doesn't look like my old boss."
"He was made up to look like your employer," Wentworth insisted. "Remember that the light in the hall was not very bright when you met the man you thought was your employer and gave him the package of diamonds at his request. The interview was short and unexpected. You had no thought of treachery."
"But why does he want to kill me?"
"Obviously," replied Wentworth gravely, "you have no possession which he desires. Therefore, also obviously, you know something which he wishes to silence forever by death."
"But I don't know any such thing."
"A man may know many things," replied Wentworth, smiling, "which he does not know he knows."
A door slammed in the house — the first break in the silence. Softly Wentworth went to the door and placed his ear against it, but he could hear nothing. He dared not leave the still-weak Selwyn there upon the floor, yet he wanted nothing better than to dart from the room, to merge himself into the shadows of the gloomy house and to fight the man who was below.
Slowly he returned to the man whose life he had just saved and began to question him minutely about the brief interview he had had with his supposed employer.
"Don't you know," Wentworth said, "that you might have remained and proved your innocence? The diamonds could not have been found in your possession, and it would have been unbelievable that you should have returned to your employer and invented such an apparently absurd story if it were not true."
"I know," admitted Selwyn gloomily, "but I lost my presence of mind and ran away. Nobody would believe me innocent after I ran away." He paused. "There is one little thing that happened when I gave the package of diamonds to my boss."
"What is that?" Wentworth shot at him. "The little finger of his left hand was off at the big knuckle," Selwyn answered. "Of course I was not intimate with him, and I had never noticed it before. It sort of fascinated me, and I guess I didn't look very closely at his face. He saw me staring at his hand and he jerked it away, kind of mad."
"And that tells the story," said Wentworth decisively. "He was afraid that some day you would be caught and give evidence regarding the missing end of his finger. Your death would make that impossible."
Gradually little things were piecing themselves together. Wentworth remembered the glove on the left hand of Mr. X in the Penthouse of Madame Pompé. He remembered the big marquise ring, covering the joint of the little finger of the drunken man at the rooming house of Dorothy Canfield. No doubt the ring aided in concealing the junction of an artificial finger.
The great criminal was the man who had defrauded the diamond merchant by deceiving his innocent clerk. He was the drunken man, lying upon the bed and snoring with his face to the wall. He was Mr. X with the two guns in Madame Pompé's penthouse. The great criminal was Dr. Quornelle, who was a trifle lame because his thigh had been pierced by Wentworth's rapier in Dorothy Canfield's room.
Wentworth gave Selwyn a few more sips of brandy and water. The man really should have been in bed with a nurse giving him a spoonful of soup every now and then. But he had a very sturdy frame and appeared as though he might soon be able to walk.
Wentworth replaced his flask and turned swiftly to the door, pistol in hand. More sound could be heard from the house outside that door. There were heavy footsteps ascending the stairs. They came irregularly, not lame, but unsteady.
Through the keyhole Wentworth caught glimpses of a flashlight. He hesitated to open the door even a trifle, since the daylight in the room would filter through and reveal the fact that the door was no longer closed and locked as Dr. Quornelle had left it.
The unsteady footsteps came to the head of the stairs and stopped. Then they moved forward, but Wentworth could not tell toward which room they were headed.
Suddenly a man began speaking in a voice a bit too loud to be natural. He spoke slowly and enunciated his words with a slight difficulty. The man was drunk.
"Dr. Quornelle," the voice commenced impressively, "you are saluted by the New York press in general and by The Evening Standard in particular."
The answer, if any, could not be heard, the door cutting it off from Wentworth. But Wentworth recognized the loud voice and knew that Sparks, the reporter, was in the house and still rather drunk. How he came to be in the house was a mystery. Handicapped by the weak condition of Selwyn, Wentworth hesitated to open the door, something he was to regret.
"What I want to know, Dr. Quornelle," the loud voice of Sparks continued slowly and solemnly, "is who, where, when, why and — and what for?"
Again there was a brief silence, and once more the loud voice of Sparks boomed forth.
"My dear Dr. Quornelle, I 'pologize. I thought I stated question most explish — most ex — very clearly. I shall repeat. In interest of people of New York, I wish to know why you took Madame Pompé away from big, fat radio announcer."
There may have been words in reply and there may not have been. Wentworth could not hear any, but he heard another kind of reply. A pistol shot shattered the silence of the house, and there followed the thud of a falling body.
Desperately Wentworth threw open the laboratory door and flung himself into the hall, low down upon his knees, his pistol held forward in one hand.
Electric light streamed from the library door, and through it a man leaped into the outer darkness of the hall, firing through the open laboratory door with a decision which was taken instantaneously in the very act of leaping.
Wentworth had no opportunity of using his pistol, not knowing whether the leaping man were friend or foe until after the second shot had been fired.
The house was intensely silent after the two pistol shots. The fleeing man had vanished into the deep darkness. Wentworth crouched low down against a wall where the subdued daylight from the laboratory did not reach him. Behind him, in the laboratory, a strong young man lay weak and ill from the close approach of death.
What lay in the library, where the electric light shone, could not be seen — but it was very, very still.