Dr. Medjora raised the trap-door, which revealed the secret stairway, and started down. Mr. Barnes arose to follow him, saying:

"You are taking me to some secret apartment, Doctor. I will go with you, but this trap must be left open, and I warn you that I am armed."

"You need no weapons, Mr. Barnes. No danger will threaten you. My purpose in taking you below is entirely different from what you have in your mind."

At the foot of the stairway he turned aside from the crypt of aesculapius, and led the way into the secret chamber in which the hypnotic suggestion of love had been put into operation. At this time it appeared simply as an ordinary room, the staging and curtains having been removed.

"Be seated, Mr. Barnes," said the Doctor, "and listen to me. You are laboring under a misapprehension, or else you have not told me all that you know. A most curious suspicion has been aroused in your mind.

Upon what facts is it based?"

"Perhaps it will be best for me to explain. I must again refer to the fact that your first wife was supposed to have died of diphtheria.

Your second wife falls a victim to the same malady. It is uncommon in adults. This of itself might be but a coincidence. But when I know that, on a given day, I revealed to your wife the truth about Leon, which you had carefully hidden from her for so many years, and when I subsequently discover that Madame was attacked by this disease on the very night following her visit to my office, suspicion was inevitable."

"As you insist upon going back to that old case, let me ask you how you can suppose that I induced the disease at that time?"

"Just as you have done now. By using the diphtheria bacillus."

"You forget, or you do not know, that the bacillus of diphtheria was not discovered until Klebs found it in 1883, and the fact was not known until Loffler published it in 1884. Now my wife died in 1873."

"True, these scientists made their discoveries at the time which you name, but I feel certain that you had antic.i.p.ated them. You are counted the most skilful man of the day, and I believe that you know more than has been learned by others."

"Your compliment is a doubtful one. But I will not dispute with you. I will grant, for the sake of argument, that your suspicion is natural.

You cannot proceed against me merely upon suspicion. At least you should not do so."

"My suspicion is shared by another, whose mind it has entered by a different channel."

"Who is this other?"

"Your son!"

"What do you say? Leon suspects that I have committed a crime? This is terrible! But why? Why, in the name of heaven, should he harbor such a thought against me?" The Doctor was unusually excited.

"He saw you take the culture tube, containing the bacillus, out of the laboratory."

"You say Leon saw me take a culture tube from the laboratory?" The Doctor spoke the words separately, with a pause between each, as though stung by the thought which they conveyed. Mr. Barnes merely nodded a.s.sent.

"Then the end is at hand!" muttered the Doctor, softly. "All is ready for the final experiment!" Mr. Barnes did not comprehend the meaning of what he heard, but, as the Doctor walked about the room, back and forth, like a caged animal, seemingly oblivious of the fact that he was not alone, the detective thought it wise to observe him closely lest he might attack him unawares.

Presently the Doctor stopped before the detective, and thus addressed him, in calm tones:

"Mr. Barnes, you are shrewd and you are clever. You have guessed a part of the truth, and I have decided to tell you everything."

"I warn you," said Mr. Barnes, quickly, "that what you say will be used against you."

"I will take that risk!" The Doctor smiled, and an expression akin to weariness pa.s.sed over his countenance. "You have said that, in your belief, as early as 1873, I knew of the bacillus of diphtheria, and that I inoculated my wife with it. You are right, but, nevertheless, you are mistaken when you say that she died from that malady. I must go further back, and tell you that the main source of my knowledge has been some very ancient hieroglyphical writings, which recorded what was known upon the subject by the priests of centuries ago. Much that is novel to-day, was very well understood in those times. The germ theory of disease was thoroughly worked out to a point far in advance of what has yet been accomplished in this era. The study required to translate and comprehend the cabalistic and hieroglyphical records has been very great, and it was essential that I should test each step experimentally. About the time of Mabel's death I had discovered the germ of diphtheria, but I found that my experiments with the lower animals were very unsatisfactory, owing to the fact that it does not affect them and human beings in a precisely similar manner. I therefore risked inoculating my wife."

"That was a hideous thing to do," ventured Mr. Barnes.

"From your standpoint, perhaps you are right. But I am a unique man, occupying a unique position in the world. To me alone was it given to resurrect the buried wisdom of the past. Even if I had known that the experiment might be attended by the death of my wife, whom I loved dearer than myself, I still would not have been deterred. Science transcended everything in my mind. Death must come to us all, and a few years difference in the time of its arrival is surely immaterial, and not to be weighed against the progress of scientific research. But I was confident that the disease, thus transmitted, would not prove fatal. That is, I was sure that I could effect a cure."

"But it seems that you did not do so. The woman died."

"She died from poison. I carefully attended her during her attack of diphtheria, until an unlooked-for accident occurred. I became ill myself. It was not an ailment of any consequence, but I felt that it would be safer to call in a.s.sistance, and I placed the case in the hands of Dr. Fisher. He afterwards stupidly called in Dr. Meredith.

However, despite their old fogy methods, she made a good rally and was on the safe side of the crisis, when that hypodermic case was left temptingly within her reach. I think now that she shammed sleep, in order to distract my attention from her. Morphine _habitues_ are very cunning in obtaining their coveted drug. However that may be, I was suddenly aroused to the fact that there was a movement in the bed, and turning my head, I saw her pushing the needle of the syringe under her flesh. I sprang up and hastened to her, but she had made the injection, and dropped back to the pillows, when I reached her. She had not withdrawn the needle, and I was in the act of doing that, when the nurse entered."

"Then you adhere to the story which you told upon the stand?"

"Certainly! It is the truth!"

"But, Doctor," said Mr. Barnes, "you have not, even yet, proven that she did not die of diphtheria."

"She did not! I tell you it was the morphine that deprived her of life. I know it! She died of poison! There is no question about that!"

Thus the Doctor, though admitting that he had produced the diphtheria, persistently a.s.severated that Mabel had not succ.u.mbed to its influence. Thus is explained his not advancing the theory of diphtheria as a cause of death, when arranging his defence, at the trial. To have escaped the gallows in that manner, would have been to burden his conscience with the murder of the woman whom he loved, for if she died of diphtheria, while he must have escaped conviction by the jury, he would know within his own heart that it was his hand that deprived her of life. Mr. Barnes replied:

"But there is a question in this last case. Madame died of diphtheria, and since you admit that you can produce it by inoculation, what am I to believe?"

"I care not what you believe," said the Doctor, sharply, "so long as you can prove nothing."

"Well, then, since you do not care," said the detective, nettled, "let me tell you that I believe you deliberately planned to kill your last wife. What is more, I do not doubt that a jury would adopt my views."

"In that you are utterly mistaken. Were I considering myself alone, I would permit you to accuse me, feeling perfectly confident that I would be in no danger."

"You are a bold man!"

"Not at all! Where there is no danger, there can be no special bravery. Why, my dear Mr. Barnes, you have no case at all against me.

In your own mind you think that there is ample proof, but much of what you know could not be offered to a jury. You are aware of the fact that the diphtheria bacillus was known to me prior to my first wife's death, and so you trace a connection between the two cases. But my lawyer would merely show that the discovery was made ten years after Mabel died, and any further allusion to my first trial would be ruled out. I know enough about law, to know that previous crimes, or accusations of crime, cannot be cited unless they form a part of a system, and as your idea of induced diphtheria could not be substantiated, all of that part of your evidence would be irrelevant."

"That would be a question for the presiding judge to decide."

"If he decide other than as I have stated, we would get a new trial on appeal. The law is specific, and the point is covered by endless precedents. Now then, obliged to confine yourself to positive evidence in the present case, what could you do? You think you could show a motive, but a motive may exist and not be followed by a crime, and your motive is weak besides. Next, you declare that I had the knowledge and the opportunity. I might have both, and still refrain from a murder. But you say that the tube containing the bacillus was missing from my laboratory on that very night, and that my son, Leon, saw me take it. I think that you have formed a rash conclusion on this point, because I doubt that Leon has told you any such thing. However, granting that it is true, and even that the boy would so testify, I am sure that he would admit under cross-examination that it is a common habit for me to take such tubes to my room to make slides for the microscope." The detective recalled that Leon had made this same explanation, and he realized that the Doctor had made a valuable point in his own defence. Dr. Medjora continued: "We would produce the slides which I did actually make, and, being warned by you so early, it would be easy for me to remain in your company until I could send for an expert to examine the slides, so that at the trial he would be able to testify, that from the condition of the balsam he could swear that they had been very recently made. Thus, by admitting all of the damaging parts of your evidence, and then explaining them so that they become consistent with the hypothesis of innocence, we would feel safe. You would still be at the very beginning of your case. It would devolve upon you to show that I not only made the slides, but that I likewise used a part of the contents of that tube to inoculate my wife. You would need to show how such an act were possible. You have no witness who saw me commit the deed which you charge, have you?"

"No," said Mr. Barnes, reluctantly. "But I still think that the circ.u.mstantial evidence is sufficient." Mr. Barnes felt sure that this man was guilty, and however skilfully his defence was planned he was reluctant to yield.

"It is sufficient!" said Dr. Medjora, "Not to convict me at a trial by jury, but to raise a doubt of my innocence in the minds of those, whose good will I am determined not to forfeit. Therefore I will not submit to a trial."

"How will you escape? I intend to arrest you!"

"You intend to arrest me, but your intention will not be carried into effect. I mean to place myself beyond the reach of the law."

"You do not contemplate suicide?" asked Mr. Barnes, alarmed.

"Not at all! There is no object in such an act, and good reason why I should not resort to it. You do not comprehend my position, and I must explain it to you, because I must depend upon you for a.s.sistance."

"You expect a.s.sistance from me?" Mr. Barnes was puzzled.

"Certainly, and you will grant it. I must tell you that for many years I have planned a scheme which is now on the verge of accomplishment. I wish my son Leon to marry Agnes Dudley. I had some difficulty to obtain my friend's consent, but since he has discovered that the young people love one another, he has acquiesced. Only to-day he told me this. But if he was reluctant, when Leon's parentage was unknown, he would be more so, were he to learn that I am his father."

"But I thought that Judge Dudley was your warm friend?"